Steven Rostedt (VMware) | bcea3f9 | 2018-08-16 11:23:53 -0400 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2 | /* |
| 3 | * Infrastructure for profiling code inserted by 'gcc -pg'. |
| 4 | * |
| 5 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> |
| 6 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> |
| 7 | * |
| 8 | * Originally ported from the -rt patch by: |
| 9 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> |
| 10 | * |
| 11 | * Based on code in the latency_tracer, that is: |
| 12 | * |
| 13 | * Copyright (C) 2004-2006 Ingo Molnar |
Nadia Yvette Chambers | 6d49e35 | 2012-12-06 10:39:54 +0100 | [diff] [blame] | 14 | * Copyright (C) 2004 Nadia Yvette Chambers |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 15 | */ |
| 16 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 17 | #include <linux/stop_machine.h> |
| 18 | #include <linux/clocksource.h> |
Ingo Molnar | 2993002 | 2017-02-08 18:51:36 +0100 | [diff] [blame] | 19 | #include <linux/sched/task.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 20 | #include <linux/kallsyms.h> |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 21 | #include <linux/security.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 22 | #include <linux/seq_file.h> |
Steven Rostedt (Red Hat) | 8434dc9 | 2015-01-20 12:13:40 -0500 | [diff] [blame] | 23 | #include <linux/tracefs.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 24 | #include <linux/hardirq.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 25 | #include <linux/kthread.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 26 | #include <linux/uaccess.h> |
Steven Rostedt | 5855fea | 2011-12-16 19:27:42 -0500 | [diff] [blame] | 27 | #include <linux/bsearch.h> |
Paul Gortmaker | 56d82e0 | 2011-05-26 17:53:52 -0400 | [diff] [blame] | 28 | #include <linux/module.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 29 | #include <linux/ftrace.h> |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 30 | #include <linux/sysctl.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 31 | #include <linux/slab.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 32 | #include <linux/ctype.h> |
Steven Rostedt | 6895061 | 2011-12-16 17:06:45 -0500 | [diff] [blame] | 33 | #include <linux/sort.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 34 | #include <linux/list.h> |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 35 | #include <linux/hash.h> |
Paul E. McKenney | 3f379b0 | 2010-03-05 15:03:25 -0800 | [diff] [blame] | 36 | #include <linux/rcupdate.h> |
Masami Hiramatsu | fabe38a | 2019-02-24 01:50:20 +0900 | [diff] [blame] | 37 | #include <linux/kprobes.h> |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 38 | |
Steven Rostedt | ad8d75f | 2009-04-14 19:39:12 -0400 | [diff] [blame] | 39 | #include <trace/events/sched.h> |
Steven Rostedt | 8aef2d2 | 2009-03-24 01:10:15 -0400 | [diff] [blame] | 40 | |
Steven Rostedt (VMware) | b80f0f6 | 2017-04-03 12:57:35 -0400 | [diff] [blame] | 41 | #include <asm/sections.h> |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 42 | #include <asm/setup.h> |
Abhishek Sagar | 395a59d | 2008-06-21 23:47:27 +0530 | [diff] [blame] | 43 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 44 | #include "ftrace_internal.h" |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 45 | #include "trace_output.h" |
Steven Rostedt | bac429f | 2009-03-20 12:50:56 -0400 | [diff] [blame] | 46 | #include "trace_stat.h" |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 47 | |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 48 | #define FTRACE_WARN_ON(cond) \ |
Steven Rostedt | 0778d9a | 2011-04-29 10:36:31 -0400 | [diff] [blame] | 49 | ({ \ |
| 50 | int ___r = cond; \ |
| 51 | if (WARN_ON(___r)) \ |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 52 | ftrace_kill(); \ |
Steven Rostedt | 0778d9a | 2011-04-29 10:36:31 -0400 | [diff] [blame] | 53 | ___r; \ |
| 54 | }) |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 55 | |
| 56 | #define FTRACE_WARN_ON_ONCE(cond) \ |
Steven Rostedt | 0778d9a | 2011-04-29 10:36:31 -0400 | [diff] [blame] | 57 | ({ \ |
| 58 | int ___r = cond; \ |
| 59 | if (WARN_ON_ONCE(___r)) \ |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 60 | ftrace_kill(); \ |
Steven Rostedt | 0778d9a | 2011-04-29 10:36:31 -0400 | [diff] [blame] | 61 | ___r; \ |
| 62 | }) |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 63 | |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 64 | /* hash bits for specific function selection */ |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 65 | #define FTRACE_HASH_DEFAULT_BITS 10 |
| 66 | #define FTRACE_HASH_MAX_BITS 12 |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 67 | |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 68 | #ifdef CONFIG_DYNAMIC_FTRACE |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 69 | #define INIT_OPS_HASH(opsname) \ |
| 70 | .func_hash = &opsname.local_hash, \ |
| 71 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 72 | #else |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 73 | #define INIT_OPS_HASH(opsname) |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 74 | #endif |
| 75 | |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 76 | enum { |
| 77 | FTRACE_MODIFY_ENABLE_FL = (1 << 0), |
| 78 | FTRACE_MODIFY_MAY_SLEEP_FL = (1 << 1), |
| 79 | }; |
| 80 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 81 | struct ftrace_ops ftrace_list_end __read_mostly = { |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 82 | .func = ftrace_stub, |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 83 | .flags = FTRACE_OPS_FL_STUB, |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 84 | INIT_OPS_HASH(ftrace_list_end) |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 85 | }; |
| 86 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 87 | /* ftrace_enabled is a method to turn ftrace on or off */ |
| 88 | int ftrace_enabled __read_mostly; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 89 | static int last_ftrace_enabled; |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 90 | |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 91 | /* Current function tracing op */ |
| 92 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 93 | /* What to set function_trace_op to */ |
| 94 | static struct ftrace_ops *set_function_trace_op; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 95 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 96 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 97 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 98 | struct trace_array *tr; |
| 99 | |
| 100 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) |
| 101 | return false; |
| 102 | |
| 103 | tr = ops->private; |
| 104 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 105 | return tr->function_pids != NULL || tr->function_no_pids != NULL; |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 106 | } |
| 107 | |
| 108 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
| 109 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 110 | /* |
| 111 | * ftrace_disabled is set when an anomaly is discovered. |
| 112 | * ftrace_disabled is much stronger than ftrace_enabled. |
| 113 | */ |
| 114 | static int ftrace_disabled __read_mostly; |
| 115 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 116 | DEFINE_MUTEX(ftrace_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 117 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 118 | struct ftrace_ops __rcu *ftrace_ops_list __read_mostly = &ftrace_list_end; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 119 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 120 | struct ftrace_ops global_ops; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 121 | |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 122 | #if ARCH_SUPPORTS_FTRACE_OPS |
| 123 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 124 | struct ftrace_ops *op, struct ftrace_regs *fregs); |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 125 | #else |
| 126 | /* See comment below, where ftrace_ops_list_func is defined */ |
| 127 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); |
| 128 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) |
| 129 | #endif |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 130 | |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 131 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
| 132 | { |
| 133 | #ifdef CONFIG_DYNAMIC_FTRACE |
| 134 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 135 | mutex_init(&ops->local_hash.regex_lock); |
| 136 | ops->func_hash = &ops->local_hash; |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 137 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
| 138 | } |
| 139 | #endif |
| 140 | } |
| 141 | |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 142 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 143 | struct ftrace_ops *op, struct ftrace_regs *fregs) |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 144 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 145 | struct trace_array *tr = op->private; |
Steven Rostedt (VMware) | 717e3f5 | 2020-03-19 23:40:40 -0400 | [diff] [blame] | 146 | int pid; |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 147 | |
Steven Rostedt (VMware) | 717e3f5 | 2020-03-19 23:40:40 -0400 | [diff] [blame] | 148 | if (tr) { |
| 149 | pid = this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid); |
| 150 | if (pid == FTRACE_PID_IGNORE) |
| 151 | return; |
| 152 | if (pid != FTRACE_PID_TRACE && |
| 153 | pid != current->pid) |
| 154 | return; |
| 155 | } |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 156 | |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 157 | op->saved_func(ip, parent_ip, op, fregs); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 158 | } |
| 159 | |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 160 | static void ftrace_sync_ipi(void *data) |
| 161 | { |
| 162 | /* Probably not needed, but do it anyway */ |
| 163 | smp_rmb(); |
| 164 | } |
| 165 | |
Steven Rostedt (Red Hat) | 00ccbf2 | 2015-02-19 15:56:14 +0100 | [diff] [blame] | 166 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) |
| 167 | { |
| 168 | /* |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 169 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
Steven Rostedt (Red Hat) | 00ccbf2 | 2015-02-19 15:56:14 +0100 | [diff] [blame] | 170 | * then it needs to call the list anyway. |
| 171 | */ |
Peter Zijlstra | b3a8880 | 2017-10-11 09:45:32 +0200 | [diff] [blame] | 172 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_RCU) || |
| 173 | FTRACE_FORCE_LIST_FUNC) |
Steven Rostedt (Red Hat) | 00ccbf2 | 2015-02-19 15:56:14 +0100 | [diff] [blame] | 174 | return ftrace_ops_list_func; |
| 175 | |
| 176 | return ftrace_ops_get_func(ops); |
| 177 | } |
| 178 | |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 179 | static void update_ftrace_function(void) |
| 180 | { |
| 181 | ftrace_func_t func; |
| 182 | |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 183 | /* |
Steven Rostedt (Red Hat) | f7aad4e | 2014-09-10 10:42:46 -0400 | [diff] [blame] | 184 | * Prepare the ftrace_ops that the arch callback will use. |
| 185 | * If there's only one ftrace_ops registered, the ftrace_ops_list |
| 186 | * will point to the ops we want. |
| 187 | */ |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 188 | set_function_trace_op = rcu_dereference_protected(ftrace_ops_list, |
| 189 | lockdep_is_held(&ftrace_lock)); |
Steven Rostedt (Red Hat) | f7aad4e | 2014-09-10 10:42:46 -0400 | [diff] [blame] | 190 | |
| 191 | /* If there's no ftrace_ops registered, just call the stub function */ |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 192 | if (set_function_trace_op == &ftrace_list_end) { |
Steven Rostedt (Red Hat) | f7aad4e | 2014-09-10 10:42:46 -0400 | [diff] [blame] | 193 | func = ftrace_stub; |
| 194 | |
| 195 | /* |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 196 | * If we are at the end of the list and this ops is |
Steven Rostedt | 4740974 | 2012-07-20 11:04:44 -0400 | [diff] [blame] | 197 | * recursion safe and not dynamic and the arch supports passing ops, |
| 198 | * then have the mcount trampoline call the function directly. |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 199 | */ |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 200 | } else if (rcu_dereference_protected(ftrace_ops_list->next, |
| 201 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { |
Steven Rostedt (Red Hat) | 00ccbf2 | 2015-02-19 15:56:14 +0100 | [diff] [blame] | 202 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
Steven Rostedt (Red Hat) | f7aad4e | 2014-09-10 10:42:46 -0400 | [diff] [blame] | 203 | |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 204 | } else { |
| 205 | /* Just use the default ftrace_ops */ |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 206 | set_function_trace_op = &ftrace_list_end; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 207 | func = ftrace_ops_list_func; |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 208 | } |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 209 | |
Steven Rostedt (Red Hat) | 5f8bf2d2 | 2014-07-15 11:05:12 -0400 | [diff] [blame] | 210 | update_function_graph_func(); |
| 211 | |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 212 | /* If there's no change, then do nothing more here */ |
| 213 | if (ftrace_trace_function == func) |
| 214 | return; |
| 215 | |
| 216 | /* |
| 217 | * If we are using the list function, it doesn't care |
| 218 | * about the function_trace_ops. |
| 219 | */ |
| 220 | if (func == ftrace_ops_list_func) { |
| 221 | ftrace_trace_function = func; |
| 222 | /* |
| 223 | * Don't even bother setting function_trace_ops, |
| 224 | * it would be racy to do so anyway. |
| 225 | */ |
| 226 | return; |
| 227 | } |
| 228 | |
| 229 | #ifndef CONFIG_DYNAMIC_FTRACE |
| 230 | /* |
| 231 | * For static tracing, we need to be a bit more careful. |
| 232 | * The function change takes affect immediately. Thus, |
Qiujun Huang | fdda88d | 2020-10-02 22:31:26 +0800 | [diff] [blame] | 233 | * we need to coordinate the setting of the function_trace_ops |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 234 | * with the setting of the ftrace_trace_function. |
| 235 | * |
| 236 | * Set the function to the list ops, which will call the |
| 237 | * function we want, albeit indirectly, but it handles the |
| 238 | * ftrace_ops and doesn't depend on function_trace_op. |
| 239 | */ |
| 240 | ftrace_trace_function = ftrace_ops_list_func; |
| 241 | /* |
| 242 | * Make sure all CPUs see this. Yes this is slow, but static |
| 243 | * tracing is slow and nasty to have enabled. |
| 244 | */ |
Paul E. McKenney | e5a971d | 2020-04-03 12:10:28 -0700 | [diff] [blame] | 245 | synchronize_rcu_tasks_rude(); |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 246 | /* Now all cpus are using the list ops. */ |
| 247 | function_trace_op = set_function_trace_op; |
| 248 | /* Make sure the function_trace_op is visible on all CPUs */ |
| 249 | smp_wmb(); |
| 250 | /* Nasty way to force a rmb on all cpus */ |
| 251 | smp_call_function(ftrace_sync_ipi, NULL, 1); |
| 252 | /* OK, we are all set to update the ftrace_trace_function now! */ |
| 253 | #endif /* !CONFIG_DYNAMIC_FTRACE */ |
| 254 | |
Steven Rostedt | 491d0dc | 2011-04-27 21:43:36 -0400 | [diff] [blame] | 255 | ftrace_trace_function = func; |
Steven Rostedt | 491d0dc | 2011-04-27 21:43:36 -0400 | [diff] [blame] | 256 | } |
| 257 | |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 258 | static void add_ftrace_ops(struct ftrace_ops __rcu **list, |
| 259 | struct ftrace_ops *ops) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 260 | { |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 261 | rcu_assign_pointer(ops->next, *list); |
| 262 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 263 | /* |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 264 | * We are entering ops into the list but another |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 265 | * CPU might be walking that list. We need to make sure |
| 266 | * the ops->next pointer is valid before another CPU sees |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 267 | * the ops pointer included into the list. |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 268 | */ |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 269 | rcu_assign_pointer(*list, ops); |
| 270 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 271 | |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 272 | static int remove_ftrace_ops(struct ftrace_ops __rcu **list, |
| 273 | struct ftrace_ops *ops) |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 274 | { |
| 275 | struct ftrace_ops **p; |
| 276 | |
| 277 | /* |
| 278 | * If we are removing the last function, then simply point |
| 279 | * to the ftrace_stub. |
| 280 | */ |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 281 | if (rcu_dereference_protected(*list, |
| 282 | lockdep_is_held(&ftrace_lock)) == ops && |
| 283 | rcu_dereference_protected(ops->next, |
| 284 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 285 | *list = &ftrace_list_end; |
| 286 | return 0; |
| 287 | } |
| 288 | |
| 289 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
| 290 | if (*p == ops) |
| 291 | break; |
| 292 | |
| 293 | if (*p != ops) |
| 294 | return -1; |
| 295 | |
| 296 | *p = (*p)->next; |
| 297 | return 0; |
| 298 | } |
| 299 | |
Steven Rostedt (Red Hat) | f3bea49 | 2014-07-02 23:23:31 -0400 | [diff] [blame] | 300 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
| 301 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 302 | int __register_ftrace_function(struct ftrace_ops *ops) |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 303 | { |
Steven Rostedt (Red Hat) | 591dffd | 2014-01-10 16:17:45 -0500 | [diff] [blame] | 304 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
| 305 | return -EINVAL; |
| 306 | |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 307 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
| 308 | return -EBUSY; |
| 309 | |
Masami Hiramatsu | 06aeaae | 2012-09-28 17:15:17 +0900 | [diff] [blame] | 310 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 311 | /* |
| 312 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used |
| 313 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. |
| 314 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. |
| 315 | */ |
| 316 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && |
| 317 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) |
| 318 | return -EINVAL; |
| 319 | |
| 320 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) |
| 321 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; |
| 322 | #endif |
Miroslav Benes | 7162431 | 2019-10-16 13:33:13 +0200 | [diff] [blame] | 323 | if (!ftrace_enabled && (ops->flags & FTRACE_OPS_FL_PERMANENT)) |
| 324 | return -EBUSY; |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 325 | |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 326 | if (!core_kernel_data((unsigned long)ops)) |
| 327 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; |
| 328 | |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 329 | add_ftrace_ops(&ftrace_ops_list, ops); |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 330 | |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 331 | /* Always save the function, and reset at unregistering */ |
| 332 | ops->saved_func = ops->func; |
| 333 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 334 | if (ftrace_pids_enabled(ops)) |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 335 | ops->func = ftrace_pid_func; |
| 336 | |
Steven Rostedt (Red Hat) | f3bea49 | 2014-07-02 23:23:31 -0400 | [diff] [blame] | 337 | ftrace_update_trampoline(ops); |
| 338 | |
Steven Rostedt | 491d0dc | 2011-04-27 21:43:36 -0400 | [diff] [blame] | 339 | if (ftrace_enabled) |
| 340 | update_ftrace_function(); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 341 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 342 | return 0; |
| 343 | } |
| 344 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 345 | int __unregister_ftrace_function(struct ftrace_ops *ops) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 346 | { |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 347 | int ret; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 348 | |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 349 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
| 350 | return -EBUSY; |
| 351 | |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 352 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 353 | |
Steven Rostedt | 2b49938 | 2011-05-03 22:49:52 -0400 | [diff] [blame] | 354 | if (ret < 0) |
| 355 | return ret; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 356 | |
Steven Rostedt | 491d0dc | 2011-04-27 21:43:36 -0400 | [diff] [blame] | 357 | if (ftrace_enabled) |
| 358 | update_ftrace_function(); |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 359 | |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 360 | ops->func = ops->saved_func; |
| 361 | |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 362 | return 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 363 | } |
| 364 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 365 | static void ftrace_update_pid_func(void) |
| 366 | { |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 367 | struct ftrace_ops *op; |
| 368 | |
Steven Rostedt | 491d0dc | 2011-04-27 21:43:36 -0400 | [diff] [blame] | 369 | /* Only do something if we are tracing something */ |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 370 | if (ftrace_trace_function == ftrace_stub) |
KOSAKI Motohiro | 10dd3eb | 2009-03-06 15:29:04 +0900 | [diff] [blame] | 371 | return; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 372 | |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 373 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 374 | if (op->flags & FTRACE_OPS_FL_PID) { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 375 | op->func = ftrace_pids_enabled(op) ? |
| 376 | ftrace_pid_func : op->saved_func; |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 377 | ftrace_update_trampoline(op); |
| 378 | } |
| 379 | } while_for_each_ftrace_op(op); |
| 380 | |
Steven Rostedt | 491d0dc | 2011-04-27 21:43:36 -0400 | [diff] [blame] | 381 | update_ftrace_function(); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 382 | } |
| 383 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 384 | #ifdef CONFIG_FUNCTION_PROFILER |
| 385 | struct ftrace_profile { |
| 386 | struct hlist_node node; |
| 387 | unsigned long ip; |
| 388 | unsigned long counter; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 389 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| 390 | unsigned long long time; |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 391 | unsigned long long time_squared; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 392 | #endif |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 393 | }; |
| 394 | |
| 395 | struct ftrace_profile_page { |
| 396 | struct ftrace_profile_page *next; |
| 397 | unsigned long index; |
| 398 | struct ftrace_profile records[]; |
| 399 | }; |
| 400 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 401 | struct ftrace_profile_stat { |
| 402 | atomic_t disabled; |
| 403 | struct hlist_head *hash; |
| 404 | struct ftrace_profile_page *pages; |
| 405 | struct ftrace_profile_page *start; |
| 406 | struct tracer_stat stat; |
| 407 | }; |
| 408 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 409 | #define PROFILE_RECORDS_SIZE \ |
| 410 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) |
| 411 | |
| 412 | #define PROFILES_PER_PAGE \ |
| 413 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) |
| 414 | |
Steven Rostedt | fb9fb01 | 2009-03-25 13:26:41 -0400 | [diff] [blame] | 415 | static int ftrace_profile_enabled __read_mostly; |
| 416 | |
| 417 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 418 | static DEFINE_MUTEX(ftrace_profile_lock); |
| 419 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 420 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 421 | |
Namhyung Kim | 20079eb | 2013-04-10 08:55:50 +0900 | [diff] [blame] | 422 | #define FTRACE_PROFILE_HASH_BITS 10 |
| 423 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 424 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 425 | static void * |
| 426 | function_stat_next(void *v, int idx) |
| 427 | { |
| 428 | struct ftrace_profile *rec = v; |
| 429 | struct ftrace_profile_page *pg; |
| 430 | |
| 431 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
| 432 | |
| 433 | again: |
Li Zefan | 0296e42 | 2009-06-26 11:15:37 +0800 | [diff] [blame] | 434 | if (idx != 0) |
| 435 | rec++; |
| 436 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 437 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
| 438 | pg = pg->next; |
| 439 | if (!pg) |
| 440 | return NULL; |
| 441 | rec = &pg->records[0]; |
| 442 | if (!rec->counter) |
| 443 | goto again; |
| 444 | } |
| 445 | |
| 446 | return rec; |
| 447 | } |
| 448 | |
| 449 | static void *function_stat_start(struct tracer_stat *trace) |
| 450 | { |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 451 | struct ftrace_profile_stat *stat = |
| 452 | container_of(trace, struct ftrace_profile_stat, stat); |
| 453 | |
| 454 | if (!stat || !stat->start) |
| 455 | return NULL; |
| 456 | |
| 457 | return function_stat_next(&stat->start->records[0], 0); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 458 | } |
| 459 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 460 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| 461 | /* function graph compares on total time */ |
Andy Shevchenko | 80042c8 | 2019-10-07 16:56:56 +0300 | [diff] [blame] | 462 | static int function_stat_cmp(const void *p1, const void *p2) |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 463 | { |
Andy Shevchenko | 80042c8 | 2019-10-07 16:56:56 +0300 | [diff] [blame] | 464 | const struct ftrace_profile *a = p1; |
| 465 | const struct ftrace_profile *b = p2; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 466 | |
| 467 | if (a->time < b->time) |
| 468 | return -1; |
| 469 | if (a->time > b->time) |
| 470 | return 1; |
| 471 | else |
| 472 | return 0; |
| 473 | } |
| 474 | #else |
| 475 | /* not function graph compares against hits */ |
Andy Shevchenko | 80042c8 | 2019-10-07 16:56:56 +0300 | [diff] [blame] | 476 | static int function_stat_cmp(const void *p1, const void *p2) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 477 | { |
Andy Shevchenko | 80042c8 | 2019-10-07 16:56:56 +0300 | [diff] [blame] | 478 | const struct ftrace_profile *a = p1; |
| 479 | const struct ftrace_profile *b = p2; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 480 | |
| 481 | if (a->counter < b->counter) |
| 482 | return -1; |
| 483 | if (a->counter > b->counter) |
| 484 | return 1; |
| 485 | else |
| 486 | return 0; |
| 487 | } |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 488 | #endif |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 489 | |
| 490 | static int function_stat_headers(struct seq_file *m) |
| 491 | { |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 492 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 493 | seq_puts(m, " Function " |
| 494 | "Hit Time Avg s^2\n" |
| 495 | " -------- " |
| 496 | "--- ---- --- ---\n"); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 497 | #else |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 498 | seq_puts(m, " Function Hit\n" |
| 499 | " -------- ---\n"); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 500 | #endif |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 501 | return 0; |
| 502 | } |
| 503 | |
| 504 | static int function_stat_show(struct seq_file *m, void *v) |
| 505 | { |
| 506 | struct ftrace_profile *rec = v; |
| 507 | char str[KSYM_SYMBOL_LEN]; |
Li Zefan | 3aaba20 | 2010-08-23 16:50:12 +0800 | [diff] [blame] | 508 | int ret = 0; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 509 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Steven Rostedt | 34886c8 | 2009-03-25 21:00:47 -0400 | [diff] [blame] | 510 | static struct trace_seq s; |
| 511 | unsigned long long avg; |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 512 | unsigned long long stddev; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 513 | #endif |
Li Zefan | 3aaba20 | 2010-08-23 16:50:12 +0800 | [diff] [blame] | 514 | mutex_lock(&ftrace_profile_lock); |
| 515 | |
| 516 | /* we raced with function_profile_reset() */ |
| 517 | if (unlikely(rec->counter == 0)) { |
| 518 | ret = -EBUSY; |
| 519 | goto out; |
| 520 | } |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 521 | |
Umesh Tiwari | 8e436ca | 2015-06-22 16:58:08 +0530 | [diff] [blame] | 522 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Wen Yang | e31f793 | 2020-01-03 11:02:48 +0800 | [diff] [blame] | 523 | avg = div64_ul(rec->time, rec->counter); |
Umesh Tiwari | 8e436ca | 2015-06-22 16:58:08 +0530 | [diff] [blame] | 524 | if (tracing_thresh && (avg < tracing_thresh)) |
| 525 | goto out; |
| 526 | #endif |
| 527 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 528 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 529 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 530 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 531 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 532 | seq_puts(m, " "); |
Steven Rostedt | 34886c8 | 2009-03-25 21:00:47 -0400 | [diff] [blame] | 533 | |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 534 | /* Sample standard deviation (s^2) */ |
| 535 | if (rec->counter <= 1) |
| 536 | stddev = 0; |
| 537 | else { |
Juri Lelli | 52d85d7 | 2013-06-12 12:03:18 +0200 | [diff] [blame] | 538 | /* |
| 539 | * Apply Welford's method: |
| 540 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) |
| 541 | */ |
| 542 | stddev = rec->counter * rec->time_squared - |
| 543 | rec->time * rec->time; |
| 544 | |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 545 | /* |
| 546 | * Divide only 1000 for ns^2 -> us^2 conversion. |
| 547 | * trace_print_graph_duration will divide 1000 again. |
| 548 | */ |
Wen Yang | e31f793 | 2020-01-03 11:02:48 +0800 | [diff] [blame] | 549 | stddev = div64_ul(stddev, |
| 550 | rec->counter * (rec->counter - 1) * 1000); |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 551 | } |
| 552 | |
Steven Rostedt | 34886c8 | 2009-03-25 21:00:47 -0400 | [diff] [blame] | 553 | trace_seq_init(&s); |
| 554 | trace_print_graph_duration(rec->time, &s); |
| 555 | trace_seq_puts(&s, " "); |
| 556 | trace_print_graph_duration(avg, &s); |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 557 | trace_seq_puts(&s, " "); |
| 558 | trace_print_graph_duration(stddev, &s); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 559 | trace_print_seq(m, &s); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 560 | #endif |
| 561 | seq_putc(m, '\n'); |
Li Zefan | 3aaba20 | 2010-08-23 16:50:12 +0800 | [diff] [blame] | 562 | out: |
| 563 | mutex_unlock(&ftrace_profile_lock); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 564 | |
Li Zefan | 3aaba20 | 2010-08-23 16:50:12 +0800 | [diff] [blame] | 565 | return ret; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 566 | } |
| 567 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 568 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 569 | { |
| 570 | struct ftrace_profile_page *pg; |
| 571 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 572 | pg = stat->pages = stat->start; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 573 | |
| 574 | while (pg) { |
| 575 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); |
| 576 | pg->index = 0; |
| 577 | pg = pg->next; |
| 578 | } |
| 579 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 580 | memset(stat->hash, 0, |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 581 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
| 582 | } |
| 583 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 584 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 585 | { |
| 586 | struct ftrace_profile_page *pg; |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 587 | int functions; |
| 588 | int pages; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 589 | int i; |
| 590 | |
| 591 | /* If we already allocated, do nothing */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 592 | if (stat->pages) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 593 | return 0; |
| 594 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 595 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
| 596 | if (!stat->pages) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 597 | return -ENOMEM; |
| 598 | |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 599 | #ifdef CONFIG_DYNAMIC_FTRACE |
| 600 | functions = ftrace_update_tot_cnt; |
| 601 | #else |
| 602 | /* |
| 603 | * We do not know the number of functions that exist because |
| 604 | * dynamic tracing is what counts them. With past experience |
| 605 | * we have around 20K functions. That should be more than enough. |
| 606 | * It is highly unlikely we will execute every function in |
| 607 | * the kernel. |
| 608 | */ |
| 609 | functions = 20000; |
| 610 | #endif |
| 611 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 612 | pg = stat->start = stat->pages; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 613 | |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 614 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
| 615 | |
Namhyung Kim | 39e30cd | 2013-04-01 21:46:24 +0900 | [diff] [blame] | 616 | for (i = 1; i < pages; i++) { |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 617 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 618 | if (!pg->next) |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 619 | goto out_free; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 620 | pg = pg->next; |
| 621 | } |
| 622 | |
| 623 | return 0; |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 624 | |
| 625 | out_free: |
| 626 | pg = stat->start; |
| 627 | while (pg) { |
| 628 | unsigned long tmp = (unsigned long)pg; |
| 629 | |
| 630 | pg = pg->next; |
| 631 | free_page(tmp); |
| 632 | } |
| 633 | |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 634 | stat->pages = NULL; |
| 635 | stat->start = NULL; |
| 636 | |
| 637 | return -ENOMEM; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 638 | } |
| 639 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 640 | static int ftrace_profile_init_cpu(int cpu) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 641 | { |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 642 | struct ftrace_profile_stat *stat; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 643 | int size; |
| 644 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 645 | stat = &per_cpu(ftrace_profile_stats, cpu); |
| 646 | |
| 647 | if (stat->hash) { |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 648 | /* If the profile is already created, simply reset it */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 649 | ftrace_profile_reset(stat); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 650 | return 0; |
| 651 | } |
| 652 | |
| 653 | /* |
| 654 | * We are profiling all functions, but usually only a few thousand |
| 655 | * functions are hit. We'll make a hash of 1024 items. |
| 656 | */ |
| 657 | size = FTRACE_PROFILE_HASH_SIZE; |
| 658 | |
Kees Cook | 6396bb2 | 2018-06-12 14:03:40 -0700 | [diff] [blame] | 659 | stat->hash = kcalloc(size, sizeof(struct hlist_head), GFP_KERNEL); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 660 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 661 | if (!stat->hash) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 662 | return -ENOMEM; |
| 663 | |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 664 | /* Preallocate the function profiling pages */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 665 | if (ftrace_profile_pages_init(stat) < 0) { |
| 666 | kfree(stat->hash); |
| 667 | stat->hash = NULL; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 668 | return -ENOMEM; |
| 669 | } |
| 670 | |
| 671 | return 0; |
| 672 | } |
| 673 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 674 | static int ftrace_profile_init(void) |
| 675 | { |
| 676 | int cpu; |
| 677 | int ret = 0; |
| 678 | |
Miao Xie | c4602c1 | 2013-12-16 15:20:01 +0800 | [diff] [blame] | 679 | for_each_possible_cpu(cpu) { |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 680 | ret = ftrace_profile_init_cpu(cpu); |
| 681 | if (ret) |
| 682 | break; |
| 683 | } |
| 684 | |
| 685 | return ret; |
| 686 | } |
| 687 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 688 | /* interrupts must be disabled */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 689 | static struct ftrace_profile * |
| 690 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 691 | { |
| 692 | struct ftrace_profile *rec; |
| 693 | struct hlist_head *hhd; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 694 | unsigned long key; |
| 695 | |
Namhyung Kim | 20079eb | 2013-04-10 08:55:50 +0900 | [diff] [blame] | 696 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 697 | hhd = &stat->hash[key]; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 698 | |
| 699 | if (hlist_empty(hhd)) |
| 700 | return NULL; |
| 701 | |
Steven Rostedt | 1bb539c | 2013-05-28 14:38:43 -0400 | [diff] [blame] | 702 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 703 | if (rec->ip == ip) |
| 704 | return rec; |
| 705 | } |
| 706 | |
| 707 | return NULL; |
| 708 | } |
| 709 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 710 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
| 711 | struct ftrace_profile *rec) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 712 | { |
| 713 | unsigned long key; |
| 714 | |
Namhyung Kim | 20079eb | 2013-04-10 08:55:50 +0900 | [diff] [blame] | 715 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 716 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 717 | } |
| 718 | |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 719 | /* |
| 720 | * The memory is already allocated, this simply finds a new record to use. |
| 721 | */ |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 722 | static struct ftrace_profile * |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 723 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 724 | { |
| 725 | struct ftrace_profile *rec = NULL; |
| 726 | |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 727 | /* prevent recursion (from NMIs) */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 728 | if (atomic_inc_return(&stat->disabled) != 1) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 729 | goto out; |
| 730 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 731 | /* |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 732 | * Try to find the function again since an NMI |
| 733 | * could have added it |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 734 | */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 735 | rec = ftrace_find_profiled_func(stat, ip); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 736 | if (rec) |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 737 | goto out; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 738 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 739 | if (stat->pages->index == PROFILES_PER_PAGE) { |
| 740 | if (!stat->pages->next) |
| 741 | goto out; |
| 742 | stat->pages = stat->pages->next; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 743 | } |
| 744 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 745 | rec = &stat->pages->records[stat->pages->index++]; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 746 | rec->ip = ip; |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 747 | ftrace_add_profile(stat, rec); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 748 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 749 | out: |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 750 | atomic_dec(&stat->disabled); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 751 | |
| 752 | return rec; |
| 753 | } |
| 754 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 755 | static void |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 756 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 757 | struct ftrace_ops *ops, struct ftrace_regs *fregs) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 758 | { |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 759 | struct ftrace_profile_stat *stat; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 760 | struct ftrace_profile *rec; |
| 761 | unsigned long flags; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 762 | |
| 763 | if (!ftrace_profile_enabled) |
| 764 | return; |
| 765 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 766 | local_irq_save(flags); |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 767 | |
Christoph Lameter | bdffd89 | 2014-04-29 14:17:40 -0500 | [diff] [blame] | 768 | stat = this_cpu_ptr(&ftrace_profile_stats); |
Steven Rostedt | 0f6ce3d | 2009-06-01 21:51:28 -0400 | [diff] [blame] | 769 | if (!stat->hash || !ftrace_profile_enabled) |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 770 | goto out; |
| 771 | |
| 772 | rec = ftrace_find_profiled_func(stat, ip); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 773 | if (!rec) { |
Steven Rostedt | 318e0a7 | 2009-03-25 20:06:34 -0400 | [diff] [blame] | 774 | rec = ftrace_profile_alloc(stat, ip); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 775 | if (!rec) |
| 776 | goto out; |
| 777 | } |
| 778 | |
| 779 | rec->counter++; |
| 780 | out: |
| 781 | local_irq_restore(flags); |
| 782 | } |
| 783 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 784 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Steven Rostedt (VMware) | e73e679 | 2018-11-15 12:35:13 -0500 | [diff] [blame] | 785 | static bool fgraph_graph_time = true; |
| 786 | |
| 787 | void ftrace_graph_graph_time_control(bool enable) |
| 788 | { |
| 789 | fgraph_graph_time = enable; |
| 790 | } |
| 791 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 792 | static int profile_graph_entry(struct ftrace_graph_ent *trace) |
| 793 | { |
Steven Rostedt (VMware) | b0e21a6 | 2018-11-19 20:54:08 -0500 | [diff] [blame] | 794 | struct ftrace_ret_stack *ret_stack; |
Namhyung Kim | 8861dd3 | 2016-08-31 11:55:29 +0900 | [diff] [blame] | 795 | |
Steven Rostedt | a1e2e31 | 2011-08-09 12:50:46 -0400 | [diff] [blame] | 796 | function_profile_call(trace->func, 0, NULL, NULL); |
Namhyung Kim | 8861dd3 | 2016-08-31 11:55:29 +0900 | [diff] [blame] | 797 | |
Steven Rostedt (VMware) | a8f0f9e | 2017-08-17 16:37:25 -0400 | [diff] [blame] | 798 | /* If function graph is shutting down, ret_stack can be NULL */ |
| 799 | if (!current->ret_stack) |
| 800 | return 0; |
| 801 | |
Steven Rostedt (VMware) | b0e21a6 | 2018-11-19 20:54:08 -0500 | [diff] [blame] | 802 | ret_stack = ftrace_graph_get_ret_stack(current, 0); |
| 803 | if (ret_stack) |
| 804 | ret_stack->subtime = 0; |
Namhyung Kim | 8861dd3 | 2016-08-31 11:55:29 +0900 | [diff] [blame] | 805 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 806 | return 1; |
| 807 | } |
| 808 | |
| 809 | static void profile_graph_return(struct ftrace_graph_ret *trace) |
| 810 | { |
Steven Rostedt (VMware) | b0e21a6 | 2018-11-19 20:54:08 -0500 | [diff] [blame] | 811 | struct ftrace_ret_stack *ret_stack; |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 812 | struct ftrace_profile_stat *stat; |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 813 | unsigned long long calltime; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 814 | struct ftrace_profile *rec; |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 815 | unsigned long flags; |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 816 | |
| 817 | local_irq_save(flags); |
Christoph Lameter | bdffd89 | 2014-04-29 14:17:40 -0500 | [diff] [blame] | 818 | stat = this_cpu_ptr(&ftrace_profile_stats); |
Steven Rostedt | 0f6ce3d | 2009-06-01 21:51:28 -0400 | [diff] [blame] | 819 | if (!stat->hash || !ftrace_profile_enabled) |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 820 | goto out; |
| 821 | |
Steven Rostedt | 37e44bc | 2010-04-27 21:04:24 -0400 | [diff] [blame] | 822 | /* If the calltime was zero'd ignore it */ |
| 823 | if (!trace->calltime) |
| 824 | goto out; |
| 825 | |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 826 | calltime = trace->rettime - trace->calltime; |
| 827 | |
Steven Rostedt (Red Hat) | 5557720 | 2015-09-29 19:06:50 -0400 | [diff] [blame] | 828 | if (!fgraph_graph_time) { |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 829 | |
| 830 | /* Append this call time to the parent time to subtract */ |
Steven Rostedt (VMware) | b0e21a6 | 2018-11-19 20:54:08 -0500 | [diff] [blame] | 831 | ret_stack = ftrace_graph_get_ret_stack(current, 1); |
| 832 | if (ret_stack) |
| 833 | ret_stack->subtime += calltime; |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 834 | |
Steven Rostedt (VMware) | b0e21a6 | 2018-11-19 20:54:08 -0500 | [diff] [blame] | 835 | ret_stack = ftrace_graph_get_ret_stack(current, 0); |
| 836 | if (ret_stack && ret_stack->subtime < calltime) |
| 837 | calltime -= ret_stack->subtime; |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 838 | else |
| 839 | calltime = 0; |
| 840 | } |
| 841 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 842 | rec = ftrace_find_profiled_func(stat, trace->func); |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 843 | if (rec) { |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 844 | rec->time += calltime; |
Chase Douglas | e330b3b | 2010-04-26 14:02:05 -0400 | [diff] [blame] | 845 | rec->time_squared += calltime * calltime; |
| 846 | } |
Steven Rostedt | a2a16d6 | 2009-03-24 23:17:58 -0400 | [diff] [blame] | 847 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 848 | out: |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 849 | local_irq_restore(flags); |
| 850 | } |
| 851 | |
Steven Rostedt (VMware) | 688f708 | 2018-11-15 14:06:47 -0500 | [diff] [blame] | 852 | static struct fgraph_ops fprofiler_ops = { |
| 853 | .entryfunc = &profile_graph_entry, |
| 854 | .retfunc = &profile_graph_return, |
| 855 | }; |
| 856 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 857 | static int register_ftrace_profiler(void) |
| 858 | { |
Steven Rostedt (VMware) | 688f708 | 2018-11-15 14:06:47 -0500 | [diff] [blame] | 859 | return register_ftrace_graph(&fprofiler_ops); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 860 | } |
| 861 | |
| 862 | static void unregister_ftrace_profiler(void) |
| 863 | { |
Steven Rostedt (VMware) | 688f708 | 2018-11-15 14:06:47 -0500 | [diff] [blame] | 864 | unregister_ftrace_graph(&fprofiler_ops); |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 865 | } |
| 866 | #else |
Paul McQuade | bd38c0e | 2011-05-31 20:51:55 +0100 | [diff] [blame] | 867 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
Steven Rostedt | fb9fb01 | 2009-03-25 13:26:41 -0400 | [diff] [blame] | 868 | .func = function_profile_call, |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 869 | .flags = FTRACE_OPS_FL_INITIALIZED, |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 870 | INIT_OPS_HASH(ftrace_profile_ops) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 871 | }; |
| 872 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 873 | static int register_ftrace_profiler(void) |
| 874 | { |
| 875 | return register_ftrace_function(&ftrace_profile_ops); |
| 876 | } |
| 877 | |
| 878 | static void unregister_ftrace_profiler(void) |
| 879 | { |
| 880 | unregister_ftrace_function(&ftrace_profile_ops); |
| 881 | } |
| 882 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
| 883 | |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 884 | static ssize_t |
| 885 | ftrace_profile_write(struct file *filp, const char __user *ubuf, |
| 886 | size_t cnt, loff_t *ppos) |
| 887 | { |
| 888 | unsigned long val; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 889 | int ret; |
| 890 | |
Peter Huewe | 22fe9b5 | 2011-06-07 21:58:27 +0200 | [diff] [blame] | 891 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
| 892 | if (ret) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 893 | return ret; |
| 894 | |
| 895 | val = !!val; |
| 896 | |
| 897 | mutex_lock(&ftrace_profile_lock); |
| 898 | if (ftrace_profile_enabled ^ val) { |
| 899 | if (val) { |
| 900 | ret = ftrace_profile_init(); |
| 901 | if (ret < 0) { |
| 902 | cnt = ret; |
| 903 | goto out; |
| 904 | } |
| 905 | |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 906 | ret = register_ftrace_profiler(); |
| 907 | if (ret < 0) { |
| 908 | cnt = ret; |
| 909 | goto out; |
| 910 | } |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 911 | ftrace_profile_enabled = 1; |
| 912 | } else { |
| 913 | ftrace_profile_enabled = 0; |
Steven Rostedt | 0f6ce3d | 2009-06-01 21:51:28 -0400 | [diff] [blame] | 914 | /* |
| 915 | * unregister_ftrace_profiler calls stop_machine |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 916 | * so this acts like an synchronize_rcu. |
Steven Rostedt | 0f6ce3d | 2009-06-01 21:51:28 -0400 | [diff] [blame] | 917 | */ |
Steven Rostedt | 0706f1c | 2009-03-23 23:12:58 -0400 | [diff] [blame] | 918 | unregister_ftrace_profiler(); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 919 | } |
| 920 | } |
| 921 | out: |
| 922 | mutex_unlock(&ftrace_profile_lock); |
| 923 | |
Jiri Olsa | cf8517c | 2009-10-23 19:36:16 -0400 | [diff] [blame] | 924 | *ppos += cnt; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 925 | |
| 926 | return cnt; |
| 927 | } |
| 928 | |
| 929 | static ssize_t |
| 930 | ftrace_profile_read(struct file *filp, char __user *ubuf, |
| 931 | size_t cnt, loff_t *ppos) |
| 932 | { |
Steven Rostedt | fb9fb01 | 2009-03-25 13:26:41 -0400 | [diff] [blame] | 933 | char buf[64]; /* big enough to hold a number */ |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 934 | int r; |
| 935 | |
| 936 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); |
| 937 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
| 938 | } |
| 939 | |
| 940 | static const struct file_operations ftrace_profile_fops = { |
| 941 | .open = tracing_open_generic, |
| 942 | .read = ftrace_profile_read, |
| 943 | .write = ftrace_profile_write, |
Arnd Bergmann | 6038f37 | 2010-08-15 18:52:59 +0200 | [diff] [blame] | 944 | .llseek = default_llseek, |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 945 | }; |
| 946 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 947 | /* used to initialize the real stat files */ |
| 948 | static struct tracer_stat function_stats __initdata = { |
Steven Rostedt | fb9fb01 | 2009-03-25 13:26:41 -0400 | [diff] [blame] | 949 | .name = "functions", |
| 950 | .stat_start = function_stat_start, |
| 951 | .stat_next = function_stat_next, |
| 952 | .stat_cmp = function_stat_cmp, |
| 953 | .stat_headers = function_stat_headers, |
| 954 | .stat_show = function_stat_show |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 955 | }; |
| 956 | |
Steven Rostedt (Red Hat) | 8434dc9 | 2015-01-20 12:13:40 -0500 | [diff] [blame] | 957 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 958 | { |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 959 | struct ftrace_profile_stat *stat; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 960 | struct dentry *entry; |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 961 | char *name; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 962 | int ret; |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 963 | int cpu; |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 964 | |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 965 | for_each_possible_cpu(cpu) { |
| 966 | stat = &per_cpu(ftrace_profile_stats, cpu); |
| 967 | |
Geliang Tang | 6363c6b | 2016-03-15 22:12:34 +0800 | [diff] [blame] | 968 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 969 | if (!name) { |
| 970 | /* |
| 971 | * The files created are permanent, if something happens |
| 972 | * we still do not free memory. |
| 973 | */ |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 974 | WARN(1, |
| 975 | "Could not allocate stat file for cpu %d\n", |
| 976 | cpu); |
| 977 | return; |
| 978 | } |
| 979 | stat->stat = function_stats; |
Steven Rostedt | cafb168 | 2009-03-24 20:50:39 -0400 | [diff] [blame] | 980 | stat->stat.name = name; |
| 981 | ret = register_stat_tracer(&stat->stat); |
| 982 | if (ret) { |
| 983 | WARN(1, |
| 984 | "Could not register function stat for cpu %d\n", |
| 985 | cpu); |
| 986 | kfree(name); |
| 987 | return; |
| 988 | } |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 989 | } |
| 990 | |
Steven Rostedt (Red Hat) | 8434dc9 | 2015-01-20 12:13:40 -0500 | [diff] [blame] | 991 | entry = tracefs_create_file("function_profile_enabled", 0644, |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 992 | d_tracer, NULL, &ftrace_profile_fops); |
| 993 | if (!entry) |
Joe Perches | a395d6a | 2016-03-22 14:28:09 -0700 | [diff] [blame] | 994 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 995 | } |
| 996 | |
| 997 | #else /* CONFIG_FUNCTION_PROFILER */ |
Steven Rostedt (Red Hat) | 8434dc9 | 2015-01-20 12:13:40 -0500 | [diff] [blame] | 998 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 999 | { |
| 1000 | } |
| 1001 | #endif /* CONFIG_FUNCTION_PROFILER */ |
| 1002 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1003 | #ifdef CONFIG_DYNAMIC_FTRACE |
Ingo Molnar | 73d3fd9 | 2009-02-17 11:48:18 +0100 | [diff] [blame] | 1004 | |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1005 | static struct ftrace_ops *removed_ops; |
| 1006 | |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 1007 | /* |
| 1008 | * Set when doing a global update, like enabling all recs or disabling them. |
| 1009 | * It is not set when just updating a single ftrace_ops. |
| 1010 | */ |
| 1011 | static bool update_all_ops; |
| 1012 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 1013 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 1014 | # error Dynamic ftrace depends on MCOUNT_RECORD |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 1015 | #endif |
| 1016 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 1017 | struct ftrace_func_probe { |
| 1018 | struct ftrace_probe_ops *probe_ops; |
| 1019 | struct ftrace_ops ops; |
| 1020 | struct trace_array *tr; |
| 1021 | struct list_head list; |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 1022 | void *data; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 1023 | int ref; |
| 1024 | }; |
| 1025 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1026 | /* |
| 1027 | * We make these constant because no one should touch them, |
| 1028 | * but they are used as the default "empty hash", to avoid allocating |
| 1029 | * it all the time. These are in a read only section such that if |
| 1030 | * anyone does try to modify it, it will cause an exception. |
| 1031 | */ |
| 1032 | static const struct hlist_head empty_buckets[1]; |
| 1033 | static const struct ftrace_hash empty_hash = { |
| 1034 | .buckets = (struct hlist_head *)empty_buckets, |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1035 | }; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1036 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1037 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 1038 | struct ftrace_ops global_ops = { |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 1039 | .func = ftrace_stub, |
| 1040 | .local_hash.notrace_hash = EMPTY_HASH, |
| 1041 | .local_hash.filter_hash = EMPTY_HASH, |
| 1042 | INIT_OPS_HASH(global_ops) |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 1043 | .flags = FTRACE_OPS_FL_INITIALIZED | |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 1044 | FTRACE_OPS_FL_PID, |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 1045 | }; |
| 1046 | |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1047 | /* |
Ingo Molnar | f2cc020 | 2021-03-23 18:49:35 +0100 | [diff] [blame] | 1048 | * Used by the stack unwinder to know about dynamic ftrace trampolines. |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1049 | */ |
Steven Rostedt (VMware) | 6be7fa3 | 2018-01-22 22:32:51 -0500 | [diff] [blame] | 1050 | struct ftrace_ops *ftrace_ops_trampoline(unsigned long addr) |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1051 | { |
Steven Rostedt (VMware) | 6be7fa3 | 2018-01-22 22:32:51 -0500 | [diff] [blame] | 1052 | struct ftrace_ops *op = NULL; |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1053 | |
| 1054 | /* |
| 1055 | * Some of the ops may be dynamically allocated, |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 1056 | * they are freed after a synchronize_rcu(). |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1057 | */ |
| 1058 | preempt_disable_notrace(); |
| 1059 | |
| 1060 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 1061 | /* |
| 1062 | * This is to check for dynamically allocated trampolines. |
| 1063 | * Trampolines that are in kernel text will have |
| 1064 | * core_kernel_text() return true. |
| 1065 | */ |
| 1066 | if (op->trampoline && op->trampoline_size) |
| 1067 | if (addr >= op->trampoline && |
| 1068 | addr < op->trampoline + op->trampoline_size) { |
Steven Rostedt (VMware) | 6be7fa3 | 2018-01-22 22:32:51 -0500 | [diff] [blame] | 1069 | preempt_enable_notrace(); |
| 1070 | return op; |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1071 | } |
| 1072 | } while_for_each_ftrace_op(op); |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1073 | preempt_enable_notrace(); |
| 1074 | |
Steven Rostedt (VMware) | 6be7fa3 | 2018-01-22 22:32:51 -0500 | [diff] [blame] | 1075 | return NULL; |
| 1076 | } |
| 1077 | |
| 1078 | /* |
| 1079 | * This is used by __kernel_text_address() to return true if the |
| 1080 | * address is on a dynamically allocated trampoline that would |
| 1081 | * not return true for either core_kernel_text() or |
| 1082 | * is_module_text_address(). |
| 1083 | */ |
| 1084 | bool is_ftrace_trampoline(unsigned long addr) |
| 1085 | { |
| 1086 | return ftrace_ops_trampoline(addr) != NULL; |
Steven Rostedt (Red Hat) | aec0be2 | 2014-11-18 21:14:11 -0500 | [diff] [blame] | 1087 | } |
| 1088 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1089 | struct ftrace_page { |
| 1090 | struct ftrace_page *next; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 1091 | struct dyn_ftrace *records; |
Steven Rostedt | 431aa3f | 2009-01-06 12:43:01 -0500 | [diff] [blame] | 1092 | int index; |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 1093 | int order; |
David Miller | aa5e5ce | 2008-05-13 22:06:56 -0700 | [diff] [blame] | 1094 | }; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1095 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 1096 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
| 1097 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1098 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1099 | static struct ftrace_page *ftrace_pages_start; |
| 1100 | static struct ftrace_page *ftrace_pages; |
| 1101 | |
Steven Rostedt (VMware) | 2b0cce0 | 2017-02-01 12:19:33 -0500 | [diff] [blame] | 1102 | static __always_inline unsigned long |
| 1103 | ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip) |
| 1104 | { |
| 1105 | if (hash->size_bits > 0) |
| 1106 | return hash_long(ip, hash->size_bits); |
| 1107 | |
| 1108 | return 0; |
| 1109 | } |
| 1110 | |
Steven Rostedt (VMware) | 2b2c279 | 2017-02-01 15:37:07 -0500 | [diff] [blame] | 1111 | /* Only use this function if ftrace_hash_empty() has already been tested */ |
| 1112 | static __always_inline struct ftrace_func_entry * |
| 1113 | __ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1114 | { |
| 1115 | unsigned long key; |
| 1116 | struct ftrace_func_entry *entry; |
| 1117 | struct hlist_head *hhd; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1118 | |
Steven Rostedt (VMware) | 2b0cce0 | 2017-02-01 12:19:33 -0500 | [diff] [blame] | 1119 | key = ftrace_hash_key(hash, ip); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1120 | hhd = &hash->buckets[key]; |
| 1121 | |
Steven Rostedt | 1bb539c | 2013-05-28 14:38:43 -0400 | [diff] [blame] | 1122 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1123 | if (entry->ip == ip) |
| 1124 | return entry; |
| 1125 | } |
| 1126 | return NULL; |
| 1127 | } |
| 1128 | |
Steven Rostedt (VMware) | 2b2c279 | 2017-02-01 15:37:07 -0500 | [diff] [blame] | 1129 | /** |
| 1130 | * ftrace_lookup_ip - Test to see if an ip exists in an ftrace_hash |
| 1131 | * @hash: The hash to look at |
| 1132 | * @ip: The instruction pointer to test |
| 1133 | * |
| 1134 | * Search a given @hash to see if a given instruction pointer (@ip) |
| 1135 | * exists in it. |
| 1136 | * |
| 1137 | * Returns the entry that holds the @ip if found. NULL otherwise. |
| 1138 | */ |
| 1139 | struct ftrace_func_entry * |
| 1140 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) |
| 1141 | { |
| 1142 | if (ftrace_hash_empty(hash)) |
| 1143 | return NULL; |
| 1144 | |
| 1145 | return __ftrace_lookup_ip(hash, ip); |
| 1146 | } |
| 1147 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1148 | static void __add_hash_entry(struct ftrace_hash *hash, |
| 1149 | struct ftrace_func_entry *entry) |
| 1150 | { |
| 1151 | struct hlist_head *hhd; |
| 1152 | unsigned long key; |
| 1153 | |
Steven Rostedt (VMware) | 2b0cce0 | 2017-02-01 12:19:33 -0500 | [diff] [blame] | 1154 | key = ftrace_hash_key(hash, entry->ip); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1155 | hhd = &hash->buckets[key]; |
| 1156 | hlist_add_head(&entry->hlist, hhd); |
| 1157 | hash->count++; |
| 1158 | } |
| 1159 | |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1160 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) |
| 1161 | { |
| 1162 | struct ftrace_func_entry *entry; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1163 | |
| 1164 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); |
| 1165 | if (!entry) |
| 1166 | return -ENOMEM; |
| 1167 | |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1168 | entry->ip = ip; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1169 | __add_hash_entry(hash, entry); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1170 | |
| 1171 | return 0; |
| 1172 | } |
| 1173 | |
| 1174 | static void |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1175 | free_hash_entry(struct ftrace_hash *hash, |
| 1176 | struct ftrace_func_entry *entry) |
| 1177 | { |
| 1178 | hlist_del(&entry->hlist); |
| 1179 | kfree(entry); |
| 1180 | hash->count--; |
| 1181 | } |
| 1182 | |
| 1183 | static void |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1184 | remove_hash_entry(struct ftrace_hash *hash, |
| 1185 | struct ftrace_func_entry *entry) |
| 1186 | { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 1187 | hlist_del_rcu(&entry->hlist); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1188 | hash->count--; |
| 1189 | } |
| 1190 | |
| 1191 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
| 1192 | { |
| 1193 | struct hlist_head *hhd; |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 1194 | struct hlist_node *tn; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1195 | struct ftrace_func_entry *entry; |
| 1196 | int size = 1 << hash->size_bits; |
| 1197 | int i; |
| 1198 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1199 | if (!hash->count) |
| 1200 | return; |
| 1201 | |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1202 | for (i = 0; i < size; i++) { |
| 1203 | hhd = &hash->buckets[i]; |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 1204 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1205 | free_hash_entry(hash, entry); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 1206 | } |
| 1207 | FTRACE_WARN_ON(hash->count); |
| 1208 | } |
| 1209 | |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 1210 | static void free_ftrace_mod(struct ftrace_mod_load *ftrace_mod) |
| 1211 | { |
| 1212 | list_del(&ftrace_mod->list); |
| 1213 | kfree(ftrace_mod->module); |
| 1214 | kfree(ftrace_mod->func); |
| 1215 | kfree(ftrace_mod); |
| 1216 | } |
| 1217 | |
| 1218 | static void clear_ftrace_mod_list(struct list_head *head) |
| 1219 | { |
| 1220 | struct ftrace_mod_load *p, *n; |
| 1221 | |
| 1222 | /* stack tracer isn't supported yet */ |
| 1223 | if (!head) |
| 1224 | return; |
| 1225 | |
| 1226 | mutex_lock(&ftrace_lock); |
| 1227 | list_for_each_entry_safe(p, n, head, list) |
| 1228 | free_ftrace_mod(p); |
| 1229 | mutex_unlock(&ftrace_lock); |
| 1230 | } |
| 1231 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1232 | static void free_ftrace_hash(struct ftrace_hash *hash) |
| 1233 | { |
| 1234 | if (!hash || hash == EMPTY_HASH) |
| 1235 | return; |
| 1236 | ftrace_hash_clear(hash); |
| 1237 | kfree(hash->buckets); |
| 1238 | kfree(hash); |
| 1239 | } |
| 1240 | |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1241 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
| 1242 | { |
| 1243 | struct ftrace_hash *hash; |
| 1244 | |
| 1245 | hash = container_of(rcu, struct ftrace_hash, rcu); |
| 1246 | free_ftrace_hash(hash); |
| 1247 | } |
| 1248 | |
| 1249 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) |
| 1250 | { |
| 1251 | if (!hash || hash == EMPTY_HASH) |
| 1252 | return; |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 1253 | call_rcu(&hash->rcu, __free_ftrace_hash_rcu); |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1254 | } |
| 1255 | |
Jiri Olsa | 5500fa5 | 2012-02-15 15:51:54 +0100 | [diff] [blame] | 1256 | void ftrace_free_filter(struct ftrace_ops *ops) |
| 1257 | { |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 1258 | ftrace_ops_init(ops); |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 1259 | free_ftrace_hash(ops->func_hash->filter_hash); |
| 1260 | free_ftrace_hash(ops->func_hash->notrace_hash); |
Jiri Olsa | 5500fa5 | 2012-02-15 15:51:54 +0100 | [diff] [blame] | 1261 | } |
| 1262 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1263 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
| 1264 | { |
| 1265 | struct ftrace_hash *hash; |
| 1266 | int size; |
| 1267 | |
| 1268 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); |
| 1269 | if (!hash) |
| 1270 | return NULL; |
| 1271 | |
| 1272 | size = 1 << size_bits; |
Thomas Meyer | 47b0edc | 2011-11-29 22:08:00 +0100 | [diff] [blame] | 1273 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1274 | |
| 1275 | if (!hash->buckets) { |
| 1276 | kfree(hash); |
| 1277 | return NULL; |
| 1278 | } |
| 1279 | |
| 1280 | hash->size_bits = size_bits; |
| 1281 | |
| 1282 | return hash; |
| 1283 | } |
| 1284 | |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 1285 | |
| 1286 | static int ftrace_add_mod(struct trace_array *tr, |
| 1287 | const char *func, const char *module, |
| 1288 | int enable) |
| 1289 | { |
| 1290 | struct ftrace_mod_load *ftrace_mod; |
| 1291 | struct list_head *mod_head = enable ? &tr->mod_trace : &tr->mod_notrace; |
| 1292 | |
| 1293 | ftrace_mod = kzalloc(sizeof(*ftrace_mod), GFP_KERNEL); |
| 1294 | if (!ftrace_mod) |
| 1295 | return -ENOMEM; |
| 1296 | |
| 1297 | ftrace_mod->func = kstrdup(func, GFP_KERNEL); |
| 1298 | ftrace_mod->module = kstrdup(module, GFP_KERNEL); |
| 1299 | ftrace_mod->enable = enable; |
| 1300 | |
| 1301 | if (!ftrace_mod->func || !ftrace_mod->module) |
| 1302 | goto out_free; |
| 1303 | |
| 1304 | list_add(&ftrace_mod->list, mod_head); |
| 1305 | |
| 1306 | return 0; |
| 1307 | |
| 1308 | out_free: |
| 1309 | free_ftrace_mod(ftrace_mod); |
| 1310 | |
| 1311 | return -ENOMEM; |
| 1312 | } |
| 1313 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1314 | static struct ftrace_hash * |
| 1315 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) |
| 1316 | { |
| 1317 | struct ftrace_func_entry *entry; |
| 1318 | struct ftrace_hash *new_hash; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1319 | int size; |
| 1320 | int ret; |
| 1321 | int i; |
| 1322 | |
| 1323 | new_hash = alloc_ftrace_hash(size_bits); |
| 1324 | if (!new_hash) |
| 1325 | return NULL; |
| 1326 | |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 1327 | if (hash) |
| 1328 | new_hash->flags = hash->flags; |
| 1329 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1330 | /* Empty hash? */ |
Steven Rostedt | 06a51d9 | 2011-12-19 19:07:36 -0500 | [diff] [blame] | 1331 | if (ftrace_hash_empty(hash)) |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1332 | return new_hash; |
| 1333 | |
| 1334 | size = 1 << hash->size_bits; |
| 1335 | for (i = 0; i < size; i++) { |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 1336 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1337 | ret = add_hash_entry(new_hash, entry->ip); |
| 1338 | if (ret < 0) |
| 1339 | goto free_hash; |
| 1340 | } |
| 1341 | } |
| 1342 | |
| 1343 | FTRACE_WARN_ON(new_hash->count != hash->count); |
| 1344 | |
| 1345 | return new_hash; |
| 1346 | |
| 1347 | free_hash: |
| 1348 | free_ftrace_hash(new_hash); |
| 1349 | return NULL; |
| 1350 | } |
| 1351 | |
Steven Rostedt | 41fb61c | 2011-07-13 15:03:44 -0400 | [diff] [blame] | 1352 | static void |
Steven Rostedt (Red Hat) | 8426191 | 2014-08-18 13:21:08 -0400 | [diff] [blame] | 1353 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
Steven Rostedt | 41fb61c | 2011-07-13 15:03:44 -0400 | [diff] [blame] | 1354 | static void |
Steven Rostedt (Red Hat) | 8426191 | 2014-08-18 13:21:08 -0400 | [diff] [blame] | 1355 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
Steven Rostedt | 41fb61c | 2011-07-13 15:03:44 -0400 | [diff] [blame] | 1356 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 1357 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
| 1358 | struct ftrace_hash *new_hash); |
| 1359 | |
Steven Rostedt (VMware) | 714641c | 2019-11-08 12:25:46 -0500 | [diff] [blame] | 1360 | static struct ftrace_hash *dup_hash(struct ftrace_hash *src, int size) |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1361 | { |
| 1362 | struct ftrace_func_entry *entry; |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1363 | struct ftrace_hash *new_hash; |
Steven Rostedt (VMware) | 714641c | 2019-11-08 12:25:46 -0500 | [diff] [blame] | 1364 | struct hlist_head *hhd; |
| 1365 | struct hlist_node *tn; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1366 | int bits = 0; |
| 1367 | int i; |
| 1368 | |
| 1369 | /* |
Steven Rostedt (VMware) | be49313 | 2020-10-05 20:21:14 -0400 | [diff] [blame] | 1370 | * Use around half the size (max bit of it), but |
| 1371 | * a minimum of 2 is fine (as size of 0 or 1 both give 1 for bits). |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1372 | */ |
Steven Rostedt (VMware) | be49313 | 2020-10-05 20:21:14 -0400 | [diff] [blame] | 1373 | bits = fls(size / 2); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1374 | |
| 1375 | /* Don't allocate too much */ |
| 1376 | if (bits > FTRACE_HASH_MAX_BITS) |
| 1377 | bits = FTRACE_HASH_MAX_BITS; |
| 1378 | |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1379 | new_hash = alloc_ftrace_hash(bits); |
| 1380 | if (!new_hash) |
Namhyung Kim | 3e278c0 | 2017-01-20 11:44:45 +0900 | [diff] [blame] | 1381 | return NULL; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1382 | |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 1383 | new_hash->flags = src->flags; |
| 1384 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1385 | size = 1 << src->size_bits; |
| 1386 | for (i = 0; i < size; i++) { |
| 1387 | hhd = &src->buckets[i]; |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 1388 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1389 | remove_hash_entry(src, entry); |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1390 | __add_hash_entry(new_hash, entry); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1391 | } |
| 1392 | } |
Namhyung Kim | 3e278c0 | 2017-01-20 11:44:45 +0900 | [diff] [blame] | 1393 | return new_hash; |
| 1394 | } |
| 1395 | |
Steven Rostedt (VMware) | 714641c | 2019-11-08 12:25:46 -0500 | [diff] [blame] | 1396 | static struct ftrace_hash * |
| 1397 | __ftrace_hash_move(struct ftrace_hash *src) |
| 1398 | { |
| 1399 | int size = src->count; |
| 1400 | |
| 1401 | /* |
| 1402 | * If the new source is empty, just return the empty_hash. |
| 1403 | */ |
| 1404 | if (ftrace_hash_empty(src)) |
| 1405 | return EMPTY_HASH; |
| 1406 | |
| 1407 | return dup_hash(src, size); |
| 1408 | } |
| 1409 | |
Namhyung Kim | 3e278c0 | 2017-01-20 11:44:45 +0900 | [diff] [blame] | 1410 | static int |
| 1411 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
| 1412 | struct ftrace_hash **dst, struct ftrace_hash *src) |
| 1413 | { |
| 1414 | struct ftrace_hash *new_hash; |
| 1415 | int ret; |
| 1416 | |
| 1417 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ |
| 1418 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) |
| 1419 | return -EINVAL; |
| 1420 | |
| 1421 | new_hash = __ftrace_hash_move(src); |
| 1422 | if (!new_hash) |
| 1423 | return -ENOMEM; |
| 1424 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 1425 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
| 1426 | if (enable) { |
| 1427 | /* IPMODIFY should be updated only when filter_hash updating */ |
| 1428 | ret = ftrace_hash_ipmodify_update(ops, new_hash); |
| 1429 | if (ret < 0) { |
| 1430 | free_ftrace_hash(new_hash); |
| 1431 | return ret; |
| 1432 | } |
| 1433 | } |
| 1434 | |
Masami Hiramatsu | 5c27c77 | 2014-06-17 11:04:42 +0000 | [diff] [blame] | 1435 | /* |
| 1436 | * Remove the current set, update the hash and add |
| 1437 | * them back. |
| 1438 | */ |
Steven Rostedt (Red Hat) | 8426191 | 2014-08-18 13:21:08 -0400 | [diff] [blame] | 1439 | ftrace_hash_rec_disable_modify(ops, enable); |
Masami Hiramatsu | 5c27c77 | 2014-06-17 11:04:42 +0000 | [diff] [blame] | 1440 | |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1441 | rcu_assign_pointer(*dst, new_hash); |
Steven Rostedt | 07fd551 | 2011-05-05 18:03:47 -0400 | [diff] [blame] | 1442 | |
Steven Rostedt (Red Hat) | 8426191 | 2014-08-18 13:21:08 -0400 | [diff] [blame] | 1443 | ftrace_hash_rec_enable_modify(ops, enable); |
Steven Rostedt | 41fb61c | 2011-07-13 15:03:44 -0400 | [diff] [blame] | 1444 | |
Masami Hiramatsu | 5c27c77 | 2014-06-17 11:04:42 +0000 | [diff] [blame] | 1445 | return 0; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 1446 | } |
| 1447 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1448 | static bool hash_contains_ip(unsigned long ip, |
| 1449 | struct ftrace_ops_hash *hash) |
| 1450 | { |
| 1451 | /* |
| 1452 | * The function record is a match if it exists in the filter |
Qiujun Huang | fdda88d | 2020-10-02 22:31:26 +0800 | [diff] [blame] | 1453 | * hash and not in the notrace hash. Note, an empty hash is |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1454 | * considered a match for the filter hash, but an empty |
| 1455 | * notrace hash is considered not in the notrace hash. |
| 1456 | */ |
| 1457 | return (ftrace_hash_empty(hash->filter_hash) || |
Steven Rostedt (VMware) | 2b2c279 | 2017-02-01 15:37:07 -0500 | [diff] [blame] | 1458 | __ftrace_lookup_ip(hash->filter_hash, ip)) && |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1459 | (ftrace_hash_empty(hash->notrace_hash) || |
Steven Rostedt (VMware) | 2b2c279 | 2017-02-01 15:37:07 -0500 | [diff] [blame] | 1460 | !__ftrace_lookup_ip(hash->notrace_hash, ip)); |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1461 | } |
| 1462 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1463 | /* |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1464 | * Test the hashes for this ops to see if we want to call |
| 1465 | * the ops->func or not. |
| 1466 | * |
| 1467 | * It's a match if the ip is in the ops->filter_hash or |
| 1468 | * the filter_hash does not exist or is empty, |
| 1469 | * AND |
| 1470 | * the ip is not in the ops->notrace_hash. |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 1471 | * |
| 1472 | * This needs to be called with preemption disabled as |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 1473 | * the hashes are freed with call_rcu(). |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1474 | */ |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 1475 | int |
Steven Rostedt (Red Hat) | 195a8af | 2013-07-23 22:06:15 -0400 | [diff] [blame] | 1476 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1477 | { |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1478 | struct ftrace_ops_hash hash; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1479 | int ret; |
| 1480 | |
Steven Rostedt (Red Hat) | 195a8af | 2013-07-23 22:06:15 -0400 | [diff] [blame] | 1481 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
| 1482 | /* |
| 1483 | * There's a small race when adding ops that the ftrace handler |
| 1484 | * that wants regs, may be called without them. We can not |
| 1485 | * allow that handler to be called if regs is NULL. |
| 1486 | */ |
| 1487 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) |
| 1488 | return 0; |
| 1489 | #endif |
| 1490 | |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 1491 | rcu_assign_pointer(hash.filter_hash, ops->func_hash->filter_hash); |
| 1492 | rcu_assign_pointer(hash.notrace_hash, ops->func_hash->notrace_hash); |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1493 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1494 | if (hash_contains_ip(ip, &hash)) |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1495 | ret = 1; |
| 1496 | else |
| 1497 | ret = 0; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1498 | |
| 1499 | return ret; |
| 1500 | } |
| 1501 | |
| 1502 | /* |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1503 | * This is a double for. Do not use 'break' to break out of the loop, |
| 1504 | * you must use a goto. |
| 1505 | */ |
| 1506 | #define do_for_each_ftrace_rec(pg, rec) \ |
| 1507 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ |
| 1508 | int _____i; \ |
| 1509 | for (_____i = 0; _____i < pg->index; _____i++) { \ |
| 1510 | rec = &pg->records[_____i]; |
| 1511 | |
| 1512 | #define while_for_each_ftrace_rec() \ |
| 1513 | } \ |
| 1514 | } |
Abhishek Sagar | ecea656 | 2008-06-21 23:47:53 +0530 | [diff] [blame] | 1515 | |
Steven Rostedt | 5855fea | 2011-12-16 19:27:42 -0500 | [diff] [blame] | 1516 | |
| 1517 | static int ftrace_cmp_recs(const void *a, const void *b) |
| 1518 | { |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1519 | const struct dyn_ftrace *key = a; |
| 1520 | const struct dyn_ftrace *rec = b; |
Steven Rostedt | 5855fea | 2011-12-16 19:27:42 -0500 | [diff] [blame] | 1521 | |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1522 | if (key->flags < rec->ip) |
Steven Rostedt | 5855fea | 2011-12-16 19:27:42 -0500 | [diff] [blame] | 1523 | return -1; |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1524 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
| 1525 | return 1; |
| 1526 | return 0; |
| 1527 | } |
| 1528 | |
Steven Rostedt (VMware) | 7e16f58 | 2019-11-08 12:26:46 -0500 | [diff] [blame] | 1529 | static struct dyn_ftrace *lookup_rec(unsigned long start, unsigned long end) |
| 1530 | { |
| 1531 | struct ftrace_page *pg; |
| 1532 | struct dyn_ftrace *rec = NULL; |
| 1533 | struct dyn_ftrace key; |
| 1534 | |
| 1535 | key.ip = start; |
| 1536 | key.flags = end; /* overload flags, as it is unsigned long */ |
| 1537 | |
| 1538 | for (pg = ftrace_pages_start; pg; pg = pg->next) { |
| 1539 | if (end < pg->records[0].ip || |
| 1540 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) |
| 1541 | continue; |
| 1542 | rec = bsearch(&key, pg->records, pg->index, |
| 1543 | sizeof(struct dyn_ftrace), |
| 1544 | ftrace_cmp_recs); |
Artem Savkov | d9815bf | 2020-03-06 18:43:17 +0100 | [diff] [blame] | 1545 | if (rec) |
| 1546 | break; |
Steven Rostedt (VMware) | 7e16f58 | 2019-11-08 12:26:46 -0500 | [diff] [blame] | 1547 | } |
| 1548 | return rec; |
| 1549 | } |
| 1550 | |
Michael Ellerman | 04cf31a | 2016-03-24 22:04:01 +1100 | [diff] [blame] | 1551 | /** |
| 1552 | * ftrace_location_range - return the first address of a traced location |
| 1553 | * if it touches the given ip range |
| 1554 | * @start: start of range to search. |
| 1555 | * @end: end of range to search (inclusive). @end points to the last byte |
| 1556 | * to check. |
| 1557 | * |
| 1558 | * Returns rec->ip if the related ftrace location is a least partly within |
| 1559 | * the given address range. That is, the first address of the instruction |
| 1560 | * that is either a NOP or call to the function tracer. It checks the ftrace |
| 1561 | * internal tables to determine if the address belongs or not. |
| 1562 | */ |
| 1563 | unsigned long ftrace_location_range(unsigned long start, unsigned long end) |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1564 | { |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1565 | struct dyn_ftrace *rec; |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1566 | |
Steven Rostedt (VMware) | 7e16f58 | 2019-11-08 12:26:46 -0500 | [diff] [blame] | 1567 | rec = lookup_rec(start, end); |
| 1568 | if (rec) |
| 1569 | return rec->ip; |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1570 | |
Steven Rostedt | 5855fea | 2011-12-16 19:27:42 -0500 | [diff] [blame] | 1571 | return 0; |
| 1572 | } |
| 1573 | |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 1574 | /** |
| 1575 | * ftrace_location - return true if the ip giving is a traced location |
| 1576 | * @ip: the instruction pointer to check |
| 1577 | * |
Steven Rostedt | f0cf973 | 2012-04-25 14:39:54 -0400 | [diff] [blame] | 1578 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 1579 | * That is, the instruction that is either a NOP or call to |
| 1580 | * the function tracer. It checks the ftrace internal tables to |
| 1581 | * determine if the address belongs or not. |
| 1582 | */ |
Steven Rostedt | f0cf973 | 2012-04-25 14:39:54 -0400 | [diff] [blame] | 1583 | unsigned long ftrace_location(unsigned long ip) |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 1584 | { |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1585 | return ftrace_location_range(ip, ip); |
| 1586 | } |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 1587 | |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1588 | /** |
| 1589 | * ftrace_text_reserved - return true if range contains an ftrace location |
| 1590 | * @start: start of range to search |
| 1591 | * @end: end of range to search (inclusive). @end points to the last byte to check. |
| 1592 | * |
| 1593 | * Returns 1 if @start and @end contains a ftrace location. |
| 1594 | * That is, the instruction that is either a NOP or call to |
| 1595 | * the function tracer. It checks the ftrace internal tables to |
| 1596 | * determine if the address belongs or not. |
| 1597 | */ |
Sasha Levin | d88471c | 2013-01-09 18:09:20 -0500 | [diff] [blame] | 1598 | int ftrace_text_reserved(const void *start, const void *end) |
Steven Rostedt | a650e02 | 2012-04-25 13:48:13 -0400 | [diff] [blame] | 1599 | { |
Steven Rostedt | f0cf973 | 2012-04-25 14:39:54 -0400 | [diff] [blame] | 1600 | unsigned long ret; |
| 1601 | |
| 1602 | ret = ftrace_location_range((unsigned long)start, |
| 1603 | (unsigned long)end); |
| 1604 | |
| 1605 | return (int)!!ret; |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 1606 | } |
| 1607 | |
Steven Rostedt (Red Hat) | 4fbb48c | 2014-04-30 22:35:48 -0400 | [diff] [blame] | 1608 | /* Test if ops registered to this rec needs regs */ |
| 1609 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) |
| 1610 | { |
| 1611 | struct ftrace_ops *ops; |
| 1612 | bool keep_regs = false; |
| 1613 | |
| 1614 | for (ops = ftrace_ops_list; |
| 1615 | ops != &ftrace_list_end; ops = ops->next) { |
| 1616 | /* pass rec in as regs to have non-NULL val */ |
| 1617 | if (ftrace_ops_test(ops, rec->ip, rec)) { |
| 1618 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { |
| 1619 | keep_regs = true; |
| 1620 | break; |
| 1621 | } |
| 1622 | } |
| 1623 | } |
| 1624 | |
| 1625 | return keep_regs; |
| 1626 | } |
| 1627 | |
Cheng Jian | a124692 | 2019-05-04 19:39:39 +0800 | [diff] [blame] | 1628 | static struct ftrace_ops * |
| 1629 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); |
| 1630 | static struct ftrace_ops * |
Naveen N. Rao | 4c75b0f | 2020-11-26 23:38:38 +0530 | [diff] [blame] | 1631 | ftrace_find_tramp_ops_any_other(struct dyn_ftrace *rec, struct ftrace_ops *op_exclude); |
| 1632 | static struct ftrace_ops * |
Cheng Jian | a124692 | 2019-05-04 19:39:39 +0800 | [diff] [blame] | 1633 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); |
| 1634 | |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1635 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1636 | int filter_hash, |
| 1637 | bool inc) |
| 1638 | { |
| 1639 | struct ftrace_hash *hash; |
| 1640 | struct ftrace_hash *other_hash; |
| 1641 | struct ftrace_page *pg; |
| 1642 | struct dyn_ftrace *rec; |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1643 | bool update = false; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1644 | int count = 0; |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 1645 | int all = false; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1646 | |
| 1647 | /* Only update if the ops has been registered */ |
| 1648 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1649 | return false; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1650 | |
| 1651 | /* |
| 1652 | * In the filter_hash case: |
| 1653 | * If the count is zero, we update all records. |
| 1654 | * Otherwise we just update the items in the hash. |
| 1655 | * |
| 1656 | * In the notrace_hash case: |
| 1657 | * We enable the update in the hash. |
| 1658 | * As disabling notrace means enabling the tracing, |
| 1659 | * and enabling notrace means disabling, the inc variable |
| 1660 | * gets inversed. |
| 1661 | */ |
| 1662 | if (filter_hash) { |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 1663 | hash = ops->func_hash->filter_hash; |
| 1664 | other_hash = ops->func_hash->notrace_hash; |
Steven Rostedt | 06a51d9 | 2011-12-19 19:07:36 -0500 | [diff] [blame] | 1665 | if (ftrace_hash_empty(hash)) |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 1666 | all = true; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1667 | } else { |
| 1668 | inc = !inc; |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 1669 | hash = ops->func_hash->notrace_hash; |
| 1670 | other_hash = ops->func_hash->filter_hash; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1671 | /* |
| 1672 | * If the notrace hash has no items, |
| 1673 | * then there's nothing to do. |
| 1674 | */ |
Steven Rostedt | 06a51d9 | 2011-12-19 19:07:36 -0500 | [diff] [blame] | 1675 | if (ftrace_hash_empty(hash)) |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1676 | return false; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1677 | } |
| 1678 | |
| 1679 | do_for_each_ftrace_rec(pg, rec) { |
| 1680 | int in_other_hash = 0; |
| 1681 | int in_hash = 0; |
| 1682 | int match = 0; |
| 1683 | |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 1684 | if (rec->flags & FTRACE_FL_DISABLED) |
| 1685 | continue; |
| 1686 | |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1687 | if (all) { |
| 1688 | /* |
| 1689 | * Only the filter_hash affects all records. |
| 1690 | * Update if the record is not in the notrace hash. |
| 1691 | */ |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 1692 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1693 | match = 1; |
| 1694 | } else { |
Steven Rostedt | 06a51d9 | 2011-12-19 19:07:36 -0500 | [diff] [blame] | 1695 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
| 1696 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1697 | |
| 1698 | /* |
Steven Rostedt (Red Hat) | 19eab4a | 2014-05-07 15:06:14 -0400 | [diff] [blame] | 1699 | * If filter_hash is set, we want to match all functions |
| 1700 | * that are in the hash but not in the other hash. |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1701 | * |
Steven Rostedt (Red Hat) | 19eab4a | 2014-05-07 15:06:14 -0400 | [diff] [blame] | 1702 | * If filter_hash is not set, then we are decrementing. |
| 1703 | * That means we match anything that is in the hash |
| 1704 | * and also in the other_hash. That is, we need to turn |
| 1705 | * off functions in the other hash because they are disabled |
| 1706 | * by this hash. |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1707 | */ |
| 1708 | if (filter_hash && in_hash && !in_other_hash) |
| 1709 | match = 1; |
| 1710 | else if (!filter_hash && in_hash && |
Steven Rostedt | 06a51d9 | 2011-12-19 19:07:36 -0500 | [diff] [blame] | 1711 | (in_other_hash || ftrace_hash_empty(other_hash))) |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1712 | match = 1; |
| 1713 | } |
| 1714 | if (!match) |
| 1715 | continue; |
| 1716 | |
| 1717 | if (inc) { |
| 1718 | rec->flags++; |
Steven Rostedt (Red Hat) | 0376bde | 2014-05-07 13:46:45 -0400 | [diff] [blame] | 1719 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1720 | return false; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1721 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 1722 | if (ops->flags & FTRACE_OPS_FL_DIRECT) |
| 1723 | rec->flags |= FTRACE_FL_DIRECT; |
| 1724 | |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1725 | /* |
| 1726 | * If there's only a single callback registered to a |
| 1727 | * function, and the ops has a trampoline registered |
| 1728 | * for it, then we can call it directly. |
| 1729 | */ |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1730 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1731 | rec->flags |= FTRACE_FL_TRAMP; |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1732 | else |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1733 | /* |
| 1734 | * If we are adding another function callback |
| 1735 | * to this function, and the previous had a |
Steven Rostedt (Red Hat) | bce0b6c | 2014-08-20 23:57:04 -0400 | [diff] [blame] | 1736 | * custom trampoline in use, then we need to go |
| 1737 | * back to the default trampoline. |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1738 | */ |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1739 | rec->flags &= ~FTRACE_FL_TRAMP; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1740 | |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 1741 | /* |
| 1742 | * If any ops wants regs saved for this function |
| 1743 | * then all ops will get saved regs. |
| 1744 | */ |
| 1745 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) |
| 1746 | rec->flags |= FTRACE_FL_REGS; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1747 | } else { |
Steven Rostedt (Red Hat) | 0376bde | 2014-05-07 13:46:45 -0400 | [diff] [blame] | 1748 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1749 | return false; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1750 | rec->flags--; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1751 | |
Steven Rostedt (Red Hat) | 4fbb48c | 2014-04-30 22:35:48 -0400 | [diff] [blame] | 1752 | /* |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 1753 | * Only the internal direct_ops should have the |
| 1754 | * DIRECT flag set. Thus, if it is removing a |
| 1755 | * function, then that function should no longer |
| 1756 | * be direct. |
| 1757 | */ |
| 1758 | if (ops->flags & FTRACE_OPS_FL_DIRECT) |
| 1759 | rec->flags &= ~FTRACE_FL_DIRECT; |
| 1760 | |
| 1761 | /* |
Steven Rostedt (Red Hat) | 4fbb48c | 2014-04-30 22:35:48 -0400 | [diff] [blame] | 1762 | * If the rec had REGS enabled and the ops that is |
| 1763 | * being removed had REGS set, then see if there is |
| 1764 | * still any ops for this record that wants regs. |
| 1765 | * If not, we can stop recording them. |
| 1766 | */ |
Steven Rostedt (Red Hat) | 0376bde | 2014-05-07 13:46:45 -0400 | [diff] [blame] | 1767 | if (ftrace_rec_count(rec) > 0 && |
Steven Rostedt (Red Hat) | 4fbb48c | 2014-04-30 22:35:48 -0400 | [diff] [blame] | 1768 | rec->flags & FTRACE_FL_REGS && |
| 1769 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { |
| 1770 | if (!test_rec_ops_needs_regs(rec)) |
| 1771 | rec->flags &= ~FTRACE_FL_REGS; |
| 1772 | } |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1773 | |
| 1774 | /* |
Cheng Jian | a124692 | 2019-05-04 19:39:39 +0800 | [diff] [blame] | 1775 | * The TRAMP needs to be set only if rec count |
| 1776 | * is decremented to one, and the ops that is |
| 1777 | * left has a trampoline. As TRAMP can only be |
| 1778 | * enabled if there is only a single ops attached |
| 1779 | * to it. |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1780 | */ |
Cheng Jian | a124692 | 2019-05-04 19:39:39 +0800 | [diff] [blame] | 1781 | if (ftrace_rec_count(rec) == 1 && |
Naveen N. Rao | 4c75b0f | 2020-11-26 23:38:38 +0530 | [diff] [blame] | 1782 | ftrace_find_tramp_ops_any_other(rec, ops)) |
Cheng Jian | a124692 | 2019-05-04 19:39:39 +0800 | [diff] [blame] | 1783 | rec->flags |= FTRACE_FL_TRAMP; |
| 1784 | else |
| 1785 | rec->flags &= ~FTRACE_FL_TRAMP; |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 1786 | |
| 1787 | /* |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 1788 | * flags will be cleared in ftrace_check_record() |
| 1789 | * if rec count is zero. |
| 1790 | */ |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1791 | } |
| 1792 | count++; |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1793 | |
| 1794 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 1795 | update |= ftrace_test_record(rec, true) != FTRACE_UPDATE_IGNORE; |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1796 | |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1797 | /* Shortcut, if we handled all records, we are done. */ |
| 1798 | if (!all && count == hash->count) |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1799 | return update; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1800 | } while_for_each_ftrace_rec(); |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1801 | |
| 1802 | return update; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1803 | } |
| 1804 | |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1805 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1806 | int filter_hash) |
| 1807 | { |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1808 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1809 | } |
| 1810 | |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1811 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1812 | int filter_hash) |
| 1813 | { |
Jiri Olsa | 84b6d3e | 2016-03-16 15:34:32 +0100 | [diff] [blame] | 1814 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 1815 | } |
| 1816 | |
Steven Rostedt (Red Hat) | 8426191 | 2014-08-18 13:21:08 -0400 | [diff] [blame] | 1817 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
| 1818 | int filter_hash, int inc) |
| 1819 | { |
| 1820 | struct ftrace_ops *op; |
| 1821 | |
| 1822 | __ftrace_hash_rec_update(ops, filter_hash, inc); |
| 1823 | |
| 1824 | if (ops->func_hash != &global_ops.local_hash) |
| 1825 | return; |
| 1826 | |
| 1827 | /* |
| 1828 | * If the ops shares the global_ops hash, then we need to update |
| 1829 | * all ops that are enabled and use this hash. |
| 1830 | */ |
| 1831 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 1832 | /* Already done */ |
| 1833 | if (op == ops) |
| 1834 | continue; |
| 1835 | if (op->func_hash == &global_ops.local_hash) |
| 1836 | __ftrace_hash_rec_update(op, filter_hash, inc); |
| 1837 | } while_for_each_ftrace_op(op); |
| 1838 | } |
| 1839 | |
| 1840 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, |
| 1841 | int filter_hash) |
| 1842 | { |
| 1843 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); |
| 1844 | } |
| 1845 | |
| 1846 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, |
| 1847 | int filter_hash) |
| 1848 | { |
| 1849 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); |
| 1850 | } |
| 1851 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 1852 | /* |
| 1853 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK |
| 1854 | * or no-needed to update, -EBUSY if it detects a conflict of the flag |
| 1855 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. |
| 1856 | * Note that old_hash and new_hash has below meanings |
| 1857 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) |
| 1858 | * - If the hash is EMPTY_HASH, it hits nothing |
| 1859 | * - Anything else hits the recs which match the hash entries. |
| 1860 | */ |
| 1861 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, |
| 1862 | struct ftrace_hash *old_hash, |
| 1863 | struct ftrace_hash *new_hash) |
| 1864 | { |
| 1865 | struct ftrace_page *pg; |
| 1866 | struct dyn_ftrace *rec, *end = NULL; |
| 1867 | int in_old, in_new; |
| 1868 | |
| 1869 | /* Only update if the ops has been registered */ |
| 1870 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) |
| 1871 | return 0; |
| 1872 | |
| 1873 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) |
| 1874 | return 0; |
| 1875 | |
| 1876 | /* |
| 1877 | * Since the IPMODIFY is a very address sensitive action, we do not |
| 1878 | * allow ftrace_ops to set all functions to new hash. |
| 1879 | */ |
| 1880 | if (!new_hash || !old_hash) |
| 1881 | return -EINVAL; |
| 1882 | |
| 1883 | /* Update rec->flags */ |
| 1884 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt (Red Hat) | 546fece | 2016-11-14 16:31:49 -0500 | [diff] [blame] | 1885 | |
| 1886 | if (rec->flags & FTRACE_FL_DISABLED) |
| 1887 | continue; |
| 1888 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 1889 | /* We need to update only differences of filter_hash */ |
| 1890 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); |
| 1891 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); |
| 1892 | if (in_old == in_new) |
| 1893 | continue; |
| 1894 | |
| 1895 | if (in_new) { |
| 1896 | /* New entries must ensure no others are using it */ |
| 1897 | if (rec->flags & FTRACE_FL_IPMODIFY) |
| 1898 | goto rollback; |
| 1899 | rec->flags |= FTRACE_FL_IPMODIFY; |
| 1900 | } else /* Removed entry */ |
| 1901 | rec->flags &= ~FTRACE_FL_IPMODIFY; |
| 1902 | } while_for_each_ftrace_rec(); |
| 1903 | |
| 1904 | return 0; |
| 1905 | |
| 1906 | rollback: |
| 1907 | end = rec; |
| 1908 | |
| 1909 | /* Roll back what we did above */ |
| 1910 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt (Red Hat) | 546fece | 2016-11-14 16:31:49 -0500 | [diff] [blame] | 1911 | |
| 1912 | if (rec->flags & FTRACE_FL_DISABLED) |
| 1913 | continue; |
| 1914 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 1915 | if (rec == end) |
| 1916 | goto err_out; |
| 1917 | |
| 1918 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); |
| 1919 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); |
| 1920 | if (in_old == in_new) |
| 1921 | continue; |
| 1922 | |
| 1923 | if (in_new) |
| 1924 | rec->flags &= ~FTRACE_FL_IPMODIFY; |
| 1925 | else |
| 1926 | rec->flags |= FTRACE_FL_IPMODIFY; |
| 1927 | } while_for_each_ftrace_rec(); |
| 1928 | |
| 1929 | err_out: |
| 1930 | return -EBUSY; |
| 1931 | } |
| 1932 | |
| 1933 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) |
| 1934 | { |
| 1935 | struct ftrace_hash *hash = ops->func_hash->filter_hash; |
| 1936 | |
| 1937 | if (ftrace_hash_empty(hash)) |
| 1938 | hash = NULL; |
| 1939 | |
| 1940 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); |
| 1941 | } |
| 1942 | |
| 1943 | /* Disabling always succeeds */ |
| 1944 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) |
| 1945 | { |
| 1946 | struct ftrace_hash *hash = ops->func_hash->filter_hash; |
| 1947 | |
| 1948 | if (ftrace_hash_empty(hash)) |
| 1949 | hash = NULL; |
| 1950 | |
| 1951 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); |
| 1952 | } |
| 1953 | |
| 1954 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
| 1955 | struct ftrace_hash *new_hash) |
| 1956 | { |
| 1957 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; |
| 1958 | |
| 1959 | if (ftrace_hash_empty(old_hash)) |
| 1960 | old_hash = NULL; |
| 1961 | |
| 1962 | if (ftrace_hash_empty(new_hash)) |
| 1963 | new_hash = NULL; |
| 1964 | |
| 1965 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); |
| 1966 | } |
| 1967 | |
Steven Rostedt (Red Hat) | b05086c | 2015-11-25 14:13:11 -0500 | [diff] [blame] | 1968 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
Steven Rostedt | 05736a4 | 2008-09-22 14:55:47 -0700 | [diff] [blame] | 1969 | { |
Steven Rostedt (VMware) | 6c14133 | 2021-06-07 21:39:08 -0400 | [diff] [blame] | 1970 | char ins[MCOUNT_INSN_SIZE]; |
Steven Rostedt | 05736a4 | 2008-09-22 14:55:47 -0700 | [diff] [blame] | 1971 | int i; |
| 1972 | |
Steven Rostedt (VMware) | 6c14133 | 2021-06-07 21:39:08 -0400 | [diff] [blame] | 1973 | if (copy_from_kernel_nofault(ins, p, MCOUNT_INSN_SIZE)) { |
| 1974 | printk(KERN_CONT "%s[FAULT] %px\n", fmt, p); |
| 1975 | return; |
| 1976 | } |
| 1977 | |
Steven Rostedt | 05736a4 | 2008-09-22 14:55:47 -0700 | [diff] [blame] | 1978 | printk(KERN_CONT "%s", fmt); |
| 1979 | |
| 1980 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) |
Steven Rostedt (VMware) | 6c14133 | 2021-06-07 21:39:08 -0400 | [diff] [blame] | 1981 | printk(KERN_CONT "%s%02x", i ? ":" : "", ins[i]); |
Steven Rostedt | 05736a4 | 2008-09-22 14:55:47 -0700 | [diff] [blame] | 1982 | } |
| 1983 | |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 1984 | enum ftrace_bug_type ftrace_bug_type; |
Steven Rostedt (Red Hat) | b05086c | 2015-11-25 14:13:11 -0500 | [diff] [blame] | 1985 | const void *ftrace_expected; |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 1986 | |
| 1987 | static void print_bug_type(void) |
| 1988 | { |
| 1989 | switch (ftrace_bug_type) { |
| 1990 | case FTRACE_BUG_UNKNOWN: |
| 1991 | break; |
| 1992 | case FTRACE_BUG_INIT: |
| 1993 | pr_info("Initializing ftrace call sites\n"); |
| 1994 | break; |
| 1995 | case FTRACE_BUG_NOP: |
| 1996 | pr_info("Setting ftrace call site to NOP\n"); |
| 1997 | break; |
| 1998 | case FTRACE_BUG_CALL: |
| 1999 | pr_info("Setting ftrace call site to call ftrace function\n"); |
| 2000 | break; |
| 2001 | case FTRACE_BUG_UPDATE: |
| 2002 | pr_info("Updating ftrace call site to call a different ftrace function\n"); |
| 2003 | break; |
| 2004 | } |
| 2005 | } |
| 2006 | |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2007 | /** |
| 2008 | * ftrace_bug - report and shutdown function tracer |
| 2009 | * @failed: The failed type (EFAULT, EINVAL, EPERM) |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2010 | * @rec: The record that failed |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2011 | * |
| 2012 | * The arch code that enables or disables the function tracing |
| 2013 | * can call ftrace_bug() when it has detected a problem in |
| 2014 | * modifying the code. @failed should be one of either: |
| 2015 | * EFAULT - if the problem happens on reading the @ip address |
| 2016 | * EINVAL - if what is read at @ip is not what was expected |
Hariprasad Kelam | 9efb85c | 2019-03-24 00:05:23 +0530 | [diff] [blame] | 2017 | * EPERM - if the problem happens on writing to the @ip address |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2018 | */ |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2019 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2020 | { |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2021 | unsigned long ip = rec ? rec->ip : 0; |
| 2022 | |
Cheng Jian | c143b77 | 2020-05-15 10:08:28 +0000 | [diff] [blame] | 2023 | pr_info("------------[ ftrace bug ]------------\n"); |
| 2024 | |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2025 | switch (failed) { |
| 2026 | case -EFAULT: |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2027 | pr_info("ftrace faulted on modifying "); |
Dmitry Safonov | 2062a4e | 2020-06-08 21:29:56 -0700 | [diff] [blame] | 2028 | print_ip_sym(KERN_INFO, ip); |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2029 | break; |
| 2030 | case -EINVAL: |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2031 | pr_info("ftrace failed to modify "); |
Dmitry Safonov | 2062a4e | 2020-06-08 21:29:56 -0700 | [diff] [blame] | 2032 | print_ip_sym(KERN_INFO, ip); |
Steven Rostedt (Red Hat) | b05086c | 2015-11-25 14:13:11 -0500 | [diff] [blame] | 2033 | print_ip_ins(" actual: ", (unsigned char *)ip); |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2034 | pr_cont("\n"); |
Steven Rostedt (Red Hat) | b05086c | 2015-11-25 14:13:11 -0500 | [diff] [blame] | 2035 | if (ftrace_expected) { |
| 2036 | print_ip_ins(" expected: ", ftrace_expected); |
| 2037 | pr_cont("\n"); |
| 2038 | } |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2039 | break; |
| 2040 | case -EPERM: |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2041 | pr_info("ftrace faulted on writing "); |
Dmitry Safonov | 2062a4e | 2020-06-08 21:29:56 -0700 | [diff] [blame] | 2042 | print_ip_sym(KERN_INFO, ip); |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2043 | break; |
| 2044 | default: |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2045 | pr_info("ftrace faulted on unknown error "); |
Dmitry Safonov | 2062a4e | 2020-06-08 21:29:56 -0700 | [diff] [blame] | 2046 | print_ip_sym(KERN_INFO, ip); |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2047 | } |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2048 | print_bug_type(); |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2049 | if (rec) { |
| 2050 | struct ftrace_ops *ops = NULL; |
| 2051 | |
| 2052 | pr_info("ftrace record flags: %lx\n", rec->flags); |
| 2053 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), |
| 2054 | rec->flags & FTRACE_FL_REGS ? " R" : " "); |
| 2055 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
| 2056 | ops = ftrace_find_tramp_ops_any(rec); |
Steven Rostedt (Red Hat) | 39daa7b | 2015-11-25 15:12:38 -0500 | [diff] [blame] | 2057 | if (ops) { |
| 2058 | do { |
| 2059 | pr_cont("\ttramp: %pS (%pS)", |
| 2060 | (void *)ops->trampoline, |
| 2061 | (void *)ops->func); |
| 2062 | ops = ftrace_find_tramp_ops_next(rec, ops); |
| 2063 | } while (ops); |
| 2064 | } else |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2065 | pr_cont("\ttramp: ERROR!"); |
| 2066 | |
| 2067 | } |
| 2068 | ip = ftrace_get_addr_curr(rec); |
Steven Rostedt (Red Hat) | 39daa7b | 2015-11-25 15:12:38 -0500 | [diff] [blame] | 2069 | pr_cont("\n expected tramp: %lx\n", ip); |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2070 | } |
Cheng Jian | c143b77 | 2020-05-15 10:08:28 +0000 | [diff] [blame] | 2071 | |
| 2072 | FTRACE_WARN_ON_ONCE(1); |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 2073 | } |
| 2074 | |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2075 | static int ftrace_check_record(struct dyn_ftrace *rec, bool enable, bool update) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2076 | { |
Xiao Guangrong | 64fbcd1 | 2009-07-15 12:32:15 +0800 | [diff] [blame] | 2077 | unsigned long flag = 0UL; |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2078 | |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2079 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
| 2080 | |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 2081 | if (rec->flags & FTRACE_FL_DISABLED) |
| 2082 | return FTRACE_UPDATE_IGNORE; |
| 2083 | |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 2084 | /* |
Jiri Olsa | 30fb6aa | 2011-12-05 18:22:48 +0100 | [diff] [blame] | 2085 | * If we are updating calls: |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 2086 | * |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 2087 | * If the record has a ref count, then we need to enable it |
| 2088 | * because someone is using it. |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 2089 | * |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 2090 | * Otherwise we make sure its disabled. |
| 2091 | * |
Jiri Olsa | 30fb6aa | 2011-12-05 18:22:48 +0100 | [diff] [blame] | 2092 | * If we are disabling calls, then disable all records that |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 2093 | * are enabled. |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 2094 | */ |
Steven Rostedt (Red Hat) | 0376bde | 2014-05-07 13:46:45 -0400 | [diff] [blame] | 2095 | if (enable && ftrace_rec_count(rec)) |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 2096 | flag = FTRACE_FL_ENABLED; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2097 | |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2098 | /* |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2099 | * If enabling and the REGS flag does not match the REGS_EN, or |
| 2100 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore |
| 2101 | * this record. Set flags to fail the compare against ENABLED. |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2102 | * Same for direct calls. |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2103 | */ |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2104 | if (flag) { |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2105 | if (!(rec->flags & FTRACE_FL_REGS) != |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2106 | !(rec->flags & FTRACE_FL_REGS_EN)) |
| 2107 | flag |= FTRACE_FL_REGS; |
| 2108 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2109 | if (!(rec->flags & FTRACE_FL_TRAMP) != |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2110 | !(rec->flags & FTRACE_FL_TRAMP_EN)) |
| 2111 | flag |= FTRACE_FL_TRAMP; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2112 | |
| 2113 | /* |
| 2114 | * Direct calls are special, as count matters. |
| 2115 | * We must test the record for direct, if the |
| 2116 | * DIRECT and DIRECT_EN do not match, but only |
| 2117 | * if the count is 1. That's because, if the |
| 2118 | * count is something other than one, we do not |
| 2119 | * want the direct enabled (it will be done via the |
| 2120 | * direct helper). But if DIRECT_EN is set, and |
| 2121 | * the count is not one, we need to clear it. |
| 2122 | */ |
| 2123 | if (ftrace_rec_count(rec) == 1) { |
| 2124 | if (!(rec->flags & FTRACE_FL_DIRECT) != |
| 2125 | !(rec->flags & FTRACE_FL_DIRECT_EN)) |
| 2126 | flag |= FTRACE_FL_DIRECT; |
| 2127 | } else if (rec->flags & FTRACE_FL_DIRECT_EN) { |
| 2128 | flag |= FTRACE_FL_DIRECT; |
| 2129 | } |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2130 | } |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2131 | |
Xiao Guangrong | 64fbcd1 | 2009-07-15 12:32:15 +0800 | [diff] [blame] | 2132 | /* If the state of this record hasn't changed, then do nothing */ |
| 2133 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2134 | return FTRACE_UPDATE_IGNORE; |
Xiao Guangrong | 64fbcd1 | 2009-07-15 12:32:15 +0800 | [diff] [blame] | 2135 | |
| 2136 | if (flag) { |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2137 | /* Save off if rec is being enabled (for return value) */ |
| 2138 | flag ^= rec->flags & FTRACE_FL_ENABLED; |
| 2139 | |
| 2140 | if (update) { |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2141 | rec->flags |= FTRACE_FL_ENABLED; |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2142 | if (flag & FTRACE_FL_REGS) { |
| 2143 | if (rec->flags & FTRACE_FL_REGS) |
| 2144 | rec->flags |= FTRACE_FL_REGS_EN; |
| 2145 | else |
| 2146 | rec->flags &= ~FTRACE_FL_REGS_EN; |
| 2147 | } |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2148 | if (flag & FTRACE_FL_TRAMP) { |
| 2149 | if (rec->flags & FTRACE_FL_TRAMP) |
| 2150 | rec->flags |= FTRACE_FL_TRAMP_EN; |
| 2151 | else |
| 2152 | rec->flags &= ~FTRACE_FL_TRAMP_EN; |
| 2153 | } |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 2154 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2155 | if (flag & FTRACE_FL_DIRECT) { |
| 2156 | /* |
| 2157 | * If there's only one user (direct_ops helper) |
| 2158 | * then we can call the direct function |
| 2159 | * directly (no ftrace trampoline). |
| 2160 | */ |
| 2161 | if (ftrace_rec_count(rec) == 1) { |
| 2162 | if (rec->flags & FTRACE_FL_DIRECT) |
| 2163 | rec->flags |= FTRACE_FL_DIRECT_EN; |
| 2164 | else |
| 2165 | rec->flags &= ~FTRACE_FL_DIRECT_EN; |
| 2166 | } else { |
| 2167 | /* |
| 2168 | * Can only call directly if there's |
| 2169 | * only one callback to the function. |
| 2170 | */ |
| 2171 | rec->flags &= ~FTRACE_FL_DIRECT_EN; |
| 2172 | } |
| 2173 | } |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2174 | } |
| 2175 | |
| 2176 | /* |
| 2177 | * If this record is being updated from a nop, then |
| 2178 | * return UPDATE_MAKE_CALL. |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2179 | * Otherwise, |
| 2180 | * return UPDATE_MODIFY_CALL to tell the caller to convert |
Steven Rostedt (Red Hat) | f1b2f2b | 2014-05-07 16:09:49 -0400 | [diff] [blame] | 2181 | * from the save regs, to a non-save regs function or |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2182 | * vice versa, or from a trampoline call. |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2183 | */ |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2184 | if (flag & FTRACE_FL_ENABLED) { |
| 2185 | ftrace_bug_type = FTRACE_BUG_CALL; |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2186 | return FTRACE_UPDATE_MAKE_CALL; |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2187 | } |
Steven Rostedt (Red Hat) | f1b2f2b | 2014-05-07 16:09:49 -0400 | [diff] [blame] | 2188 | |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2189 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
Steven Rostedt (Red Hat) | f1b2f2b | 2014-05-07 16:09:49 -0400 | [diff] [blame] | 2190 | return FTRACE_UPDATE_MODIFY_CALL; |
Xiao Guangrong | 64fbcd1 | 2009-07-15 12:32:15 +0800 | [diff] [blame] | 2191 | } |
| 2192 | |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2193 | if (update) { |
| 2194 | /* If there's no more users, clear all flags */ |
Steven Rostedt (Red Hat) | 0376bde | 2014-05-07 13:46:45 -0400 | [diff] [blame] | 2195 | if (!ftrace_rec_count(rec)) |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2196 | rec->flags = 0; |
| 2197 | else |
Steven Rostedt (Red Hat) | b24d443 | 2015-03-04 23:10:28 -0500 | [diff] [blame] | 2198 | /* |
| 2199 | * Just disable the record, but keep the ops TRAMP |
| 2200 | * and REGS states. The _EN flags must be disabled though. |
| 2201 | */ |
| 2202 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2203 | FTRACE_FL_REGS_EN | FTRACE_FL_DIRECT_EN); |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2204 | } |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2205 | |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2206 | ftrace_bug_type = FTRACE_BUG_NOP; |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2207 | return FTRACE_UPDATE_MAKE_NOP; |
| 2208 | } |
| 2209 | |
| 2210 | /** |
| 2211 | * ftrace_update_record, set a record that now is tracing or not |
| 2212 | * @rec: the record to update |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2213 | * @enable: set to true if the record is tracing, false to force disable |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2214 | * |
| 2215 | * The records that represent all functions that can be traced need |
| 2216 | * to be updated when tracing has been enabled. |
| 2217 | */ |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2218 | int ftrace_update_record(struct dyn_ftrace *rec, bool enable) |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2219 | { |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2220 | return ftrace_check_record(rec, enable, true); |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2221 | } |
| 2222 | |
| 2223 | /** |
| 2224 | * ftrace_test_record, check if the record has been enabled or not |
| 2225 | * @rec: the record to test |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2226 | * @enable: set to true to check if enabled, false if it is disabled |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2227 | * |
| 2228 | * The arch code may need to test if a record is already set to |
| 2229 | * tracing to determine how to modify the function code that it |
| 2230 | * represents. |
| 2231 | */ |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2232 | int ftrace_test_record(struct dyn_ftrace *rec, bool enable) |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2233 | { |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2234 | return ftrace_check_record(rec, enable, false); |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2235 | } |
| 2236 | |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2237 | static struct ftrace_ops * |
Steven Rostedt (Red Hat) | 5fecaa0 | 2014-07-24 16:00:31 -0400 | [diff] [blame] | 2238 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) |
| 2239 | { |
| 2240 | struct ftrace_ops *op; |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2241 | unsigned long ip = rec->ip; |
Steven Rostedt (Red Hat) | 5fecaa0 | 2014-07-24 16:00:31 -0400 | [diff] [blame] | 2242 | |
| 2243 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 2244 | |
| 2245 | if (!op->trampoline) |
| 2246 | continue; |
| 2247 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2248 | if (hash_contains_ip(ip, op->func_hash)) |
Steven Rostedt (Red Hat) | 5fecaa0 | 2014-07-24 16:00:31 -0400 | [diff] [blame] | 2249 | return op; |
| 2250 | } while_for_each_ftrace_op(op); |
| 2251 | |
| 2252 | return NULL; |
| 2253 | } |
| 2254 | |
| 2255 | static struct ftrace_ops * |
Naveen N. Rao | 4c75b0f | 2020-11-26 23:38:38 +0530 | [diff] [blame] | 2256 | ftrace_find_tramp_ops_any_other(struct dyn_ftrace *rec, struct ftrace_ops *op_exclude) |
| 2257 | { |
| 2258 | struct ftrace_ops *op; |
| 2259 | unsigned long ip = rec->ip; |
| 2260 | |
| 2261 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 2262 | |
| 2263 | if (op == op_exclude || !op->trampoline) |
| 2264 | continue; |
| 2265 | |
| 2266 | if (hash_contains_ip(ip, op->func_hash)) |
| 2267 | return op; |
| 2268 | } while_for_each_ftrace_op(op); |
| 2269 | |
| 2270 | return NULL; |
| 2271 | } |
| 2272 | |
| 2273 | static struct ftrace_ops * |
Steven Rostedt (Red Hat) | 39daa7b | 2015-11-25 15:12:38 -0500 | [diff] [blame] | 2274 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, |
| 2275 | struct ftrace_ops *op) |
| 2276 | { |
| 2277 | unsigned long ip = rec->ip; |
| 2278 | |
| 2279 | while_for_each_ftrace_op(op) { |
| 2280 | |
| 2281 | if (!op->trampoline) |
| 2282 | continue; |
| 2283 | |
| 2284 | if (hash_contains_ip(ip, op->func_hash)) |
| 2285 | return op; |
Kaitao Cheng | 026bb84 | 2020-05-29 22:12:14 +0800 | [diff] [blame] | 2286 | } |
Steven Rostedt (Red Hat) | 39daa7b | 2015-11-25 15:12:38 -0500 | [diff] [blame] | 2287 | |
| 2288 | return NULL; |
| 2289 | } |
| 2290 | |
| 2291 | static struct ftrace_ops * |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2292 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) |
| 2293 | { |
| 2294 | struct ftrace_ops *op; |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2295 | unsigned long ip = rec->ip; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2296 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2297 | /* |
| 2298 | * Need to check removed ops first. |
| 2299 | * If they are being removed, and this rec has a tramp, |
| 2300 | * and this rec is in the ops list, then it would be the |
| 2301 | * one with the tramp. |
| 2302 | */ |
| 2303 | if (removed_ops) { |
| 2304 | if (hash_contains_ip(ip, &removed_ops->old_hash)) |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2305 | return removed_ops; |
| 2306 | } |
| 2307 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2308 | /* |
| 2309 | * Need to find the current trampoline for a rec. |
| 2310 | * Now, a trampoline is only attached to a rec if there |
| 2311 | * was a single 'ops' attached to it. But this can be called |
| 2312 | * when we are adding another op to the rec or removing the |
| 2313 | * current one. Thus, if the op is being added, we can |
| 2314 | * ignore it because it hasn't attached itself to the rec |
Steven Rostedt (Red Hat) | 4fc4090 | 2014-10-24 14:48:35 -0400 | [diff] [blame] | 2315 | * yet. |
| 2316 | * |
| 2317 | * If an ops is being modified (hooking to different functions) |
| 2318 | * then we don't care about the new functions that are being |
| 2319 | * added, just the old ones (that are probably being removed). |
| 2320 | * |
| 2321 | * If we are adding an ops to a function that already is using |
| 2322 | * a trampoline, it needs to be removed (trampolines are only |
| 2323 | * for single ops connected), then an ops that is not being |
| 2324 | * modified also needs to be checked. |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2325 | */ |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2326 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2327 | |
| 2328 | if (!op->trampoline) |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2329 | continue; |
| 2330 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2331 | /* |
| 2332 | * If the ops is being added, it hasn't gotten to |
| 2333 | * the point to be removed from this tree yet. |
| 2334 | */ |
| 2335 | if (op->flags & FTRACE_OPS_FL_ADDING) |
| 2336 | continue; |
| 2337 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2338 | |
Steven Rostedt (Red Hat) | 4fc4090 | 2014-10-24 14:48:35 -0400 | [diff] [blame] | 2339 | /* |
| 2340 | * If the ops is being modified and is in the old |
| 2341 | * hash, then it is probably being removed from this |
| 2342 | * function. |
| 2343 | */ |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2344 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
| 2345 | hash_contains_ip(ip, &op->old_hash)) |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2346 | return op; |
Steven Rostedt (Red Hat) | 4fc4090 | 2014-10-24 14:48:35 -0400 | [diff] [blame] | 2347 | /* |
| 2348 | * If the ops is not being added or modified, and it's |
| 2349 | * in its normal filter hash, then this must be the one |
| 2350 | * we want! |
| 2351 | */ |
| 2352 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && |
| 2353 | hash_contains_ip(ip, op->func_hash)) |
| 2354 | return op; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2355 | |
| 2356 | } while_for_each_ftrace_op(op); |
| 2357 | |
| 2358 | return NULL; |
| 2359 | } |
| 2360 | |
| 2361 | static struct ftrace_ops * |
| 2362 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) |
| 2363 | { |
| 2364 | struct ftrace_ops *op; |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2365 | unsigned long ip = rec->ip; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2366 | |
| 2367 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 2368 | /* pass rec in as regs to have non-NULL val */ |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2369 | if (hash_contains_ip(ip, op->func_hash)) |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2370 | return op; |
| 2371 | } while_for_each_ftrace_op(op); |
| 2372 | |
| 2373 | return NULL; |
| 2374 | } |
| 2375 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2376 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS |
| 2377 | /* Protected by rcu_tasks for reading, and direct_mutex for writing */ |
| 2378 | static struct ftrace_hash *direct_functions = EMPTY_HASH; |
| 2379 | static DEFINE_MUTEX(direct_mutex); |
Steven Rostedt (VMware) | a3ad1a7 | 2019-11-08 13:12:57 -0500 | [diff] [blame] | 2380 | int ftrace_direct_func_count; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2381 | |
| 2382 | /* |
| 2383 | * Search the direct_functions hash to see if the given instruction pointer |
| 2384 | * has a direct caller attached to it. |
| 2385 | */ |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 2386 | unsigned long ftrace_find_rec_direct(unsigned long ip) |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2387 | { |
| 2388 | struct ftrace_func_entry *entry; |
| 2389 | |
| 2390 | entry = __ftrace_lookup_ip(direct_functions, ip); |
| 2391 | if (!entry) |
| 2392 | return 0; |
| 2393 | |
| 2394 | return entry->direct; |
| 2395 | } |
| 2396 | |
| 2397 | static void call_direct_funcs(unsigned long ip, unsigned long pip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 2398 | struct ftrace_ops *ops, struct ftrace_regs *fregs) |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2399 | { |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 2400 | struct pt_regs *regs = ftrace_get_regs(fregs); |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2401 | unsigned long addr; |
| 2402 | |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 2403 | addr = ftrace_find_rec_direct(ip); |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2404 | if (!addr) |
| 2405 | return; |
| 2406 | |
| 2407 | arch_ftrace_set_direct_caller(regs, addr); |
| 2408 | } |
| 2409 | |
| 2410 | struct ftrace_ops direct_ops = { |
| 2411 | .func = call_direct_funcs, |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 2412 | .flags = FTRACE_OPS_FL_IPMODIFY |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2413 | | FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_REGS |
| 2414 | | FTRACE_OPS_FL_PERMANENT, |
Steven Rostedt (VMware) | 5da7cd1 | 2020-04-22 12:25:41 -0400 | [diff] [blame] | 2415 | /* |
| 2416 | * By declaring the main trampoline as this trampoline |
| 2417 | * it will never have one allocated for it. Allocated |
| 2418 | * trampolines should not call direct functions. |
| 2419 | * The direct_ops should only be called by the builtin |
| 2420 | * ftrace_regs_caller trampoline. |
| 2421 | */ |
| 2422 | .trampoline = FTRACE_REGS_ADDR, |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2423 | }; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2424 | #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ |
| 2425 | |
Steven Rostedt (Red Hat) | 7413af1 | 2014-05-06 21:34:14 -0400 | [diff] [blame] | 2426 | /** |
| 2427 | * ftrace_get_addr_new - Get the call address to set to |
| 2428 | * @rec: The ftrace record descriptor |
| 2429 | * |
| 2430 | * If the record has the FTRACE_FL_REGS set, that means that it |
| 2431 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS |
Randy Dunlap | 5c8c206 | 2020-08-06 20:32:59 -0700 | [diff] [blame] | 2432 | * is not set, then it wants to convert to the normal callback. |
Steven Rostedt (Red Hat) | 7413af1 | 2014-05-06 21:34:14 -0400 | [diff] [blame] | 2433 | * |
| 2434 | * Returns the address of the trampoline to set to |
| 2435 | */ |
| 2436 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) |
| 2437 | { |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2438 | struct ftrace_ops *ops; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2439 | unsigned long addr; |
| 2440 | |
| 2441 | if ((rec->flags & FTRACE_FL_DIRECT) && |
| 2442 | (ftrace_rec_count(rec) == 1)) { |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 2443 | addr = ftrace_find_rec_direct(rec->ip); |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2444 | if (addr) |
| 2445 | return addr; |
| 2446 | WARN_ON_ONCE(1); |
| 2447 | } |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2448 | |
| 2449 | /* Trampolines take precedence over regs */ |
| 2450 | if (rec->flags & FTRACE_FL_TRAMP) { |
| 2451 | ops = ftrace_find_tramp_ops_new(rec); |
| 2452 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { |
Steven Rostedt (Red Hat) | bce0b6c | 2014-08-20 23:57:04 -0400 | [diff] [blame] | 2453 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
| 2454 | (void *)rec->ip, (void *)rec->ip, rec->flags); |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2455 | /* Ftrace is shutting down, return anything */ |
| 2456 | return (unsigned long)FTRACE_ADDR; |
| 2457 | } |
| 2458 | return ops->trampoline; |
| 2459 | } |
| 2460 | |
Steven Rostedt (Red Hat) | 7413af1 | 2014-05-06 21:34:14 -0400 | [diff] [blame] | 2461 | if (rec->flags & FTRACE_FL_REGS) |
| 2462 | return (unsigned long)FTRACE_REGS_ADDR; |
| 2463 | else |
| 2464 | return (unsigned long)FTRACE_ADDR; |
| 2465 | } |
| 2466 | |
| 2467 | /** |
| 2468 | * ftrace_get_addr_curr - Get the call address that is already there |
| 2469 | * @rec: The ftrace record descriptor |
| 2470 | * |
| 2471 | * The FTRACE_FL_REGS_EN is set when the record already points to |
| 2472 | * a function that saves all the regs. Basically the '_EN' version |
| 2473 | * represents the current state of the function. |
| 2474 | * |
| 2475 | * Returns the address of the trampoline that is currently being called |
| 2476 | */ |
| 2477 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) |
| 2478 | { |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2479 | struct ftrace_ops *ops; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2480 | unsigned long addr; |
| 2481 | |
| 2482 | /* Direct calls take precedence over trampolines */ |
| 2483 | if (rec->flags & FTRACE_FL_DIRECT_EN) { |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 2484 | addr = ftrace_find_rec_direct(rec->ip); |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 2485 | if (addr) |
| 2486 | return addr; |
| 2487 | WARN_ON_ONCE(1); |
| 2488 | } |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2489 | |
| 2490 | /* Trampolines take precedence over regs */ |
| 2491 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
| 2492 | ops = ftrace_find_tramp_ops_curr(rec); |
| 2493 | if (FTRACE_WARN_ON(!ops)) { |
Joe Perches | a395d6a | 2016-03-22 14:28:09 -0700 | [diff] [blame] | 2494 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
| 2495 | (void *)rec->ip, (void *)rec->ip); |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2496 | /* Ftrace is shutting down, return anything */ |
| 2497 | return (unsigned long)FTRACE_ADDR; |
| 2498 | } |
| 2499 | return ops->trampoline; |
| 2500 | } |
| 2501 | |
Steven Rostedt (Red Hat) | 7413af1 | 2014-05-06 21:34:14 -0400 | [diff] [blame] | 2502 | if (rec->flags & FTRACE_FL_REGS_EN) |
| 2503 | return (unsigned long)FTRACE_REGS_ADDR; |
| 2504 | else |
| 2505 | return (unsigned long)FTRACE_ADDR; |
| 2506 | } |
| 2507 | |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2508 | static int |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2509 | __ftrace_replace_code(struct dyn_ftrace *rec, bool enable) |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2510 | { |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2511 | unsigned long ftrace_old_addr; |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2512 | unsigned long ftrace_addr; |
| 2513 | int ret; |
| 2514 | |
Steven Rostedt (Red Hat) | 7c0868e | 2014-05-08 07:01:21 -0400 | [diff] [blame] | 2515 | ftrace_addr = ftrace_get_addr_new(rec); |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2516 | |
Steven Rostedt (Red Hat) | 7c0868e | 2014-05-08 07:01:21 -0400 | [diff] [blame] | 2517 | /* This needs to be done before we call ftrace_update_record */ |
| 2518 | ftrace_old_addr = ftrace_get_addr_curr(rec); |
| 2519 | |
| 2520 | ret = ftrace_update_record(rec, enable); |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2521 | |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2522 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
| 2523 | |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2524 | switch (ret) { |
| 2525 | case FTRACE_UPDATE_IGNORE: |
| 2526 | return 0; |
| 2527 | |
| 2528 | case FTRACE_UPDATE_MAKE_CALL: |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2529 | ftrace_bug_type = FTRACE_BUG_CALL; |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2530 | return ftrace_make_call(rec, ftrace_addr); |
| 2531 | |
| 2532 | case FTRACE_UPDATE_MAKE_NOP: |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2533 | ftrace_bug_type = FTRACE_BUG_NOP; |
Steven Rostedt (Red Hat) | 39b5552 | 2014-08-17 20:59:10 -0400 | [diff] [blame] | 2534 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2535 | |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2536 | case FTRACE_UPDATE_MODIFY_CALL: |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2537 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
Steven Rostedt | 08f6fba | 2012-04-30 16:20:23 -0400 | [diff] [blame] | 2538 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2539 | } |
| 2540 | |
Hariprasad Kelam | 9efb85c | 2019-03-24 00:05:23 +0530 | [diff] [blame] | 2541 | return -1; /* unknown ftrace bug */ |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2542 | } |
| 2543 | |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2544 | void __weak ftrace_replace_code(int mod_flags) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2545 | { |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2546 | struct dyn_ftrace *rec; |
| 2547 | struct ftrace_page *pg; |
Steven Rostedt (VMware) | 7375dca | 2019-05-20 09:26:24 -0400 | [diff] [blame] | 2548 | bool enable = mod_flags & FTRACE_MODIFY_ENABLE_FL; |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2549 | int schedulable = mod_flags & FTRACE_MODIFY_MAY_SLEEP_FL; |
Steven Rostedt | 6a24a24 | 2009-02-17 11:20:26 -0500 | [diff] [blame] | 2550 | int failed; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2551 | |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 2552 | if (unlikely(ftrace_disabled)) |
| 2553 | return; |
| 2554 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 2555 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt (Red Hat) | 546fece | 2016-11-14 16:31:49 -0500 | [diff] [blame] | 2556 | |
| 2557 | if (rec->flags & FTRACE_FL_DISABLED) |
| 2558 | continue; |
| 2559 | |
Steven Rostedt | e4f5d54 | 2012-04-27 09:13:18 -0400 | [diff] [blame] | 2560 | failed = __ftrace_replace_code(rec, enable); |
Zhaolei | fa9d13c | 2009-03-13 17:16:34 +0800 | [diff] [blame] | 2561 | if (failed) { |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2562 | ftrace_bug(failed, rec); |
Steven Rostedt | 3279ba3 | 2009-10-07 16:57:56 -0400 | [diff] [blame] | 2563 | /* Stop processing */ |
| 2564 | return; |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 2565 | } |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2566 | if (schedulable) |
| 2567 | cond_resched(); |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 2568 | } while_for_each_ftrace_rec(); |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2569 | } |
| 2570 | |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2571 | struct ftrace_rec_iter { |
| 2572 | struct ftrace_page *pg; |
| 2573 | int index; |
| 2574 | }; |
| 2575 | |
| 2576 | /** |
| 2577 | * ftrace_rec_iter_start, start up iterating over traced functions |
| 2578 | * |
| 2579 | * Returns an iterator handle that is used to iterate over all |
| 2580 | * the records that represent address locations where functions |
| 2581 | * are traced. |
| 2582 | * |
| 2583 | * May return NULL if no records are available. |
| 2584 | */ |
| 2585 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) |
| 2586 | { |
| 2587 | /* |
| 2588 | * We only use a single iterator. |
| 2589 | * Protected by the ftrace_lock mutex. |
| 2590 | */ |
| 2591 | static struct ftrace_rec_iter ftrace_rec_iter; |
| 2592 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; |
| 2593 | |
| 2594 | iter->pg = ftrace_pages_start; |
| 2595 | iter->index = 0; |
| 2596 | |
| 2597 | /* Could have empty pages */ |
| 2598 | while (iter->pg && !iter->pg->index) |
| 2599 | iter->pg = iter->pg->next; |
| 2600 | |
| 2601 | if (!iter->pg) |
| 2602 | return NULL; |
| 2603 | |
| 2604 | return iter; |
| 2605 | } |
| 2606 | |
| 2607 | /** |
| 2608 | * ftrace_rec_iter_next, get the next record to process. |
| 2609 | * @iter: The handle to the iterator. |
| 2610 | * |
| 2611 | * Returns the next iterator after the given iterator @iter. |
| 2612 | */ |
| 2613 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) |
| 2614 | { |
| 2615 | iter->index++; |
| 2616 | |
| 2617 | if (iter->index >= iter->pg->index) { |
| 2618 | iter->pg = iter->pg->next; |
| 2619 | iter->index = 0; |
| 2620 | |
| 2621 | /* Could have empty pages */ |
| 2622 | while (iter->pg && !iter->pg->index) |
| 2623 | iter->pg = iter->pg->next; |
| 2624 | } |
| 2625 | |
| 2626 | if (!iter->pg) |
| 2627 | return NULL; |
| 2628 | |
| 2629 | return iter; |
| 2630 | } |
| 2631 | |
| 2632 | /** |
| 2633 | * ftrace_rec_iter_record, get the record at the iterator location |
| 2634 | * @iter: The current iterator location |
| 2635 | * |
| 2636 | * Returns the record that the current @iter is at. |
| 2637 | */ |
| 2638 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) |
| 2639 | { |
| 2640 | return &iter->pg->records[iter->index]; |
| 2641 | } |
| 2642 | |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 2643 | static int |
Mark Rutland | fbf6c73 | 2019-10-16 17:51:10 +0100 | [diff] [blame] | 2644 | ftrace_nop_initialize(struct module *mod, struct dyn_ftrace *rec) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2645 | { |
Steven Rostedt | 593eb8a | 2008-10-23 09:32:59 -0400 | [diff] [blame] | 2646 | int ret; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2647 | |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 2648 | if (unlikely(ftrace_disabled)) |
| 2649 | return 0; |
| 2650 | |
Mark Rutland | fbf6c73 | 2019-10-16 17:51:10 +0100 | [diff] [blame] | 2651 | ret = ftrace_init_nop(mod, rec); |
Steven Rostedt | 593eb8a | 2008-10-23 09:32:59 -0400 | [diff] [blame] | 2652 | if (ret) { |
Steven Rostedt (Red Hat) | 02a392a | 2015-11-25 12:50:47 -0500 | [diff] [blame] | 2653 | ftrace_bug_type = FTRACE_BUG_INIT; |
Steven Rostedt (Red Hat) | 4fd3279 | 2014-10-24 17:56:04 -0400 | [diff] [blame] | 2654 | ftrace_bug(ret, rec); |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 2655 | return 0; |
Steven Rostedt | 37ad5084 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2656 | } |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 2657 | return 1; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2658 | } |
| 2659 | |
Steven Rostedt | 000ab69 | 2009-02-17 13:35:06 -0500 | [diff] [blame] | 2660 | /* |
| 2661 | * archs can override this function if they must do something |
| 2662 | * before the modifying code is performed. |
| 2663 | */ |
| 2664 | int __weak ftrace_arch_code_modify_prepare(void) |
| 2665 | { |
| 2666 | return 0; |
| 2667 | } |
| 2668 | |
| 2669 | /* |
| 2670 | * archs can override this function if they must do something |
| 2671 | * after the modifying code is performed. |
| 2672 | */ |
| 2673 | int __weak ftrace_arch_code_modify_post_process(void) |
| 2674 | { |
| 2675 | return 0; |
| 2676 | } |
| 2677 | |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2678 | void ftrace_modify_all_code(int command) |
| 2679 | { |
Steven Rostedt (Red Hat) | 59338f7 | 2013-08-31 01:04:07 -0400 | [diff] [blame] | 2680 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2681 | int mod_flags = 0; |
Petr Mladek | cd21067f | 2014-02-24 17:12:21 +0100 | [diff] [blame] | 2682 | int err = 0; |
Steven Rostedt (Red Hat) | 59338f7 | 2013-08-31 01:04:07 -0400 | [diff] [blame] | 2683 | |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2684 | if (command & FTRACE_MAY_SLEEP) |
| 2685 | mod_flags = FTRACE_MODIFY_MAY_SLEEP_FL; |
| 2686 | |
Steven Rostedt (Red Hat) | 59338f7 | 2013-08-31 01:04:07 -0400 | [diff] [blame] | 2687 | /* |
| 2688 | * If the ftrace_caller calls a ftrace_ops func directly, |
| 2689 | * we need to make sure that it only traces functions it |
| 2690 | * expects to trace. When doing the switch of functions, |
| 2691 | * we need to update to the ftrace_ops_list_func first |
| 2692 | * before the transition between old and new calls are set, |
| 2693 | * as the ftrace_ops_list_func will check the ops hashes |
| 2694 | * to make sure the ops are having the right functions |
| 2695 | * traced. |
| 2696 | */ |
Petr Mladek | cd21067f | 2014-02-24 17:12:21 +0100 | [diff] [blame] | 2697 | if (update) { |
| 2698 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); |
| 2699 | if (FTRACE_WARN_ON(err)) |
| 2700 | return; |
| 2701 | } |
Steven Rostedt (Red Hat) | 59338f7 | 2013-08-31 01:04:07 -0400 | [diff] [blame] | 2702 | |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2703 | if (command & FTRACE_UPDATE_CALLS) |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2704 | ftrace_replace_code(mod_flags | FTRACE_MODIFY_ENABLE_FL); |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2705 | else if (command & FTRACE_DISABLE_CALLS) |
Steven Rostedt (VMware) | a0572f6 | 2018-12-05 12:48:53 -0500 | [diff] [blame] | 2706 | ftrace_replace_code(mod_flags); |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2707 | |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 2708 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
| 2709 | function_trace_op = set_function_trace_op; |
| 2710 | smp_wmb(); |
| 2711 | /* If irqs are disabled, we are in stop machine */ |
| 2712 | if (!irqs_disabled()) |
| 2713 | smp_call_function(ftrace_sync_ipi, NULL, 1); |
Petr Mladek | cd21067f | 2014-02-24 17:12:21 +0100 | [diff] [blame] | 2714 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
| 2715 | if (FTRACE_WARN_ON(err)) |
| 2716 | return; |
Steven Rostedt (Red Hat) | 405e1d8 | 2013-11-08 14:17:30 -0500 | [diff] [blame] | 2717 | } |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2718 | |
| 2719 | if (command & FTRACE_START_FUNC_RET) |
Petr Mladek | cd21067f | 2014-02-24 17:12:21 +0100 | [diff] [blame] | 2720 | err = ftrace_enable_ftrace_graph_caller(); |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2721 | else if (command & FTRACE_STOP_FUNC_RET) |
Petr Mladek | cd21067f | 2014-02-24 17:12:21 +0100 | [diff] [blame] | 2722 | err = ftrace_disable_ftrace_graph_caller(); |
| 2723 | FTRACE_WARN_ON(err); |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2724 | } |
| 2725 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 2726 | static int __ftrace_modify_code(void *data) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2727 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2728 | int *command = data; |
| 2729 | |
Steven Rostedt | 8ed3e2c | 2012-04-26 14:59:43 -0400 | [diff] [blame] | 2730 | ftrace_modify_all_code(*command); |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 2731 | |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2732 | return 0; |
| 2733 | } |
| 2734 | |
| 2735 | /** |
| 2736 | * ftrace_run_stop_machine, go back to the stop machine method |
| 2737 | * @command: The command to tell ftrace what to do |
| 2738 | * |
| 2739 | * If an arch needs to fall back to the stop machine method, the |
| 2740 | * it can call this function. |
| 2741 | */ |
| 2742 | void ftrace_run_stop_machine(int command) |
| 2743 | { |
| 2744 | stop_machine(__ftrace_modify_code, &command, NULL); |
| 2745 | } |
| 2746 | |
| 2747 | /** |
| 2748 | * arch_ftrace_update_code, modify the code to trace or not trace |
| 2749 | * @command: The command that needs to be done |
| 2750 | * |
| 2751 | * Archs can override this function if it does not need to |
| 2752 | * run stop_machine() to modify code. |
| 2753 | */ |
| 2754 | void __weak arch_ftrace_update_code(int command) |
| 2755 | { |
| 2756 | ftrace_run_stop_machine(command); |
| 2757 | } |
| 2758 | |
| 2759 | static void ftrace_run_update_code(int command) |
| 2760 | { |
| 2761 | int ret; |
| 2762 | |
| 2763 | ret = ftrace_arch_code_modify_prepare(); |
| 2764 | FTRACE_WARN_ON(ret); |
| 2765 | if (ret) |
Petr Mladek | d5b844a | 2019-06-27 10:13:34 +0200 | [diff] [blame] | 2766 | return; |
Steven Rostedt | c88fd86 | 2011-08-16 09:53:39 -0400 | [diff] [blame] | 2767 | |
| 2768 | /* |
| 2769 | * By default we use stop_machine() to modify the code. |
| 2770 | * But archs can do what ever they want as long as it |
| 2771 | * is safe. The stop_machine() is the safest, but also |
| 2772 | * produces the most overhead. |
| 2773 | */ |
| 2774 | arch_ftrace_update_code(command); |
| 2775 | |
Steven Rostedt | 000ab69 | 2009-02-17 13:35:06 -0500 | [diff] [blame] | 2776 | ret = ftrace_arch_code_modify_post_process(); |
| 2777 | FTRACE_WARN_ON(ret); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2778 | } |
| 2779 | |
Steven Rostedt (Red Hat) | 8252ecf | 2014-10-24 14:56:01 -0400 | [diff] [blame] | 2780 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
Steven Rostedt (Red Hat) | 7485058e | 2015-01-13 14:03:38 -0500 | [diff] [blame] | 2781 | struct ftrace_ops_hash *old_hash) |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2782 | { |
| 2783 | ops->flags |= FTRACE_OPS_FL_MODIFYING; |
Steven Rostedt (Red Hat) | 7485058e | 2015-01-13 14:03:38 -0500 | [diff] [blame] | 2784 | ops->old_hash.filter_hash = old_hash->filter_hash; |
| 2785 | ops->old_hash.notrace_hash = old_hash->notrace_hash; |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2786 | ftrace_run_update_code(command); |
Steven Rostedt (Red Hat) | 8252ecf | 2014-10-24 14:56:01 -0400 | [diff] [blame] | 2787 | ops->old_hash.filter_hash = NULL; |
Steven Rostedt (Red Hat) | 7485058e | 2015-01-13 14:03:38 -0500 | [diff] [blame] | 2788 | ops->old_hash.notrace_hash = NULL; |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2789 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
| 2790 | } |
| 2791 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2792 | static ftrace_func_t saved_ftrace_func; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 2793 | static int ftrace_start_up; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2794 | |
Steven Rostedt (Red Hat) | 12cce59 | 2014-07-03 15:48:16 -0400 | [diff] [blame] | 2795 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
| 2796 | { |
| 2797 | } |
| 2798 | |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 2799 | /* List of trace_ops that have allocated trampolines */ |
| 2800 | static LIST_HEAD(ftrace_ops_trampoline_list); |
| 2801 | |
| 2802 | static void ftrace_add_trampoline_to_kallsyms(struct ftrace_ops *ops) |
| 2803 | { |
| 2804 | lockdep_assert_held(&ftrace_lock); |
| 2805 | list_add_rcu(&ops->list, &ftrace_ops_trampoline_list); |
| 2806 | } |
| 2807 | |
| 2808 | static void ftrace_remove_trampoline_from_kallsyms(struct ftrace_ops *ops) |
| 2809 | { |
| 2810 | lockdep_assert_held(&ftrace_lock); |
| 2811 | list_del_rcu(&ops->list); |
Adrian Hunter | 478ece9 | 2020-09-01 12:16:17 +0300 | [diff] [blame] | 2812 | synchronize_rcu(); |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 2813 | } |
| 2814 | |
| 2815 | /* |
| 2816 | * "__builtin__ftrace" is used as a module name in /proc/kallsyms for symbols |
| 2817 | * for pages allocated for ftrace purposes, even though "__builtin__ftrace" is |
| 2818 | * not a module. |
| 2819 | */ |
| 2820 | #define FTRACE_TRAMPOLINE_MOD "__builtin__ftrace" |
| 2821 | #define FTRACE_TRAMPOLINE_SYM "ftrace_trampoline" |
| 2822 | |
| 2823 | static void ftrace_trampoline_free(struct ftrace_ops *ops) |
| 2824 | { |
| 2825 | if (ops && (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP) && |
Adrian Hunter | dd9ddf4 | 2020-05-12 15:19:14 +0300 | [diff] [blame] | 2826 | ops->trampoline) { |
Adrian Hunter | 548e1f6 | 2020-05-12 15:19:15 +0300 | [diff] [blame] | 2827 | /* |
| 2828 | * Record the text poke event before the ksymbol unregister |
| 2829 | * event. |
| 2830 | */ |
| 2831 | perf_event_text_poke((void *)ops->trampoline, |
| 2832 | (void *)ops->trampoline, |
| 2833 | ops->trampoline_size, NULL, 0); |
Adrian Hunter | dd9ddf4 | 2020-05-12 15:19:14 +0300 | [diff] [blame] | 2834 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, |
| 2835 | ops->trampoline, ops->trampoline_size, |
| 2836 | true, FTRACE_TRAMPOLINE_SYM); |
| 2837 | /* Remove from kallsyms after the perf events */ |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 2838 | ftrace_remove_trampoline_from_kallsyms(ops); |
Adrian Hunter | dd9ddf4 | 2020-05-12 15:19:14 +0300 | [diff] [blame] | 2839 | } |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 2840 | |
| 2841 | arch_ftrace_trampoline_free(ops); |
| 2842 | } |
| 2843 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2844 | static void ftrace_startup_enable(int command) |
| 2845 | { |
| 2846 | if (saved_ftrace_func != ftrace_trace_function) { |
| 2847 | saved_ftrace_func = ftrace_trace_function; |
| 2848 | command |= FTRACE_UPDATE_TRACE_FUNC; |
| 2849 | } |
| 2850 | |
| 2851 | if (!command || !ftrace_enabled) |
| 2852 | return; |
| 2853 | |
| 2854 | ftrace_run_update_code(command); |
| 2855 | } |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2856 | |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2857 | static void ftrace_startup_all(int command) |
| 2858 | { |
| 2859 | update_all_ops = true; |
| 2860 | ftrace_startup_enable(command); |
| 2861 | update_all_ops = false; |
| 2862 | } |
| 2863 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 2864 | int ftrace_startup(struct ftrace_ops *ops, int command) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2865 | { |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 2866 | int ret; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 2867 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2868 | if (unlikely(ftrace_disabled)) |
Steven Rostedt | a1cd617 | 2011-05-23 15:24:25 -0400 | [diff] [blame] | 2869 | return -ENODEV; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2870 | |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 2871 | ret = __register_ftrace_function(ops); |
| 2872 | if (ret) |
| 2873 | return ret; |
| 2874 | |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 2875 | ftrace_start_up++; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2876 | |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2877 | /* |
| 2878 | * Note that ftrace probes uses this to start up |
| 2879 | * and modify functions it will probe. But we still |
| 2880 | * set the ADDING flag for modification, as probes |
| 2881 | * do not have trampolines. If they add them in the |
| 2882 | * future, then the probes will need to distinguish |
| 2883 | * between adding and updating probes. |
| 2884 | */ |
| 2885 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; |
Steven Rostedt (Red Hat) | 66209a5 | 2014-05-06 21:57:49 -0400 | [diff] [blame] | 2886 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 2887 | ret = ftrace_hash_ipmodify_enable(ops); |
| 2888 | if (ret < 0) { |
| 2889 | /* Rollback registration process */ |
| 2890 | __unregister_ftrace_function(ops); |
| 2891 | ftrace_start_up--; |
| 2892 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
Miroslav Benes | d5e4750 | 2020-08-31 14:26:31 +0200 | [diff] [blame] | 2893 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) |
| 2894 | ftrace_trampoline_free(ops); |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 2895 | return ret; |
| 2896 | } |
| 2897 | |
Jiri Olsa | 7f50d06 | 2016-03-16 15:34:33 +0100 | [diff] [blame] | 2898 | if (ftrace_hash_rec_enable(ops, 1)) |
| 2899 | command |= FTRACE_UPDATE_CALLS; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 2900 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2901 | ftrace_startup_enable(command); |
Steven Rostedt | a1cd617 | 2011-05-23 15:24:25 -0400 | [diff] [blame] | 2902 | |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2903 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
| 2904 | |
Steven Rostedt | a1cd617 | 2011-05-23 15:24:25 -0400 | [diff] [blame] | 2905 | return 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2906 | } |
| 2907 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 2908 | int ftrace_shutdown(struct ftrace_ops *ops, int command) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2909 | { |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 2910 | int ret; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 2911 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2912 | if (unlikely(ftrace_disabled)) |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 2913 | return -ENODEV; |
| 2914 | |
| 2915 | ret = __unregister_ftrace_function(ops); |
| 2916 | if (ret) |
| 2917 | return ret; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2918 | |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 2919 | ftrace_start_up--; |
Frederic Weisbecker | 9ea1a15 | 2009-06-20 06:52:21 +0200 | [diff] [blame] | 2920 | /* |
| 2921 | * Just warn in case of unbalance, no need to kill ftrace, it's not |
| 2922 | * critical but the ftrace_call callers may be never nopped again after |
| 2923 | * further ftrace uses. |
| 2924 | */ |
| 2925 | WARN_ON_ONCE(ftrace_start_up < 0); |
| 2926 | |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 2927 | /* Disabling ipmodify never fails */ |
| 2928 | ftrace_hash_ipmodify_disable(ops); |
Jiri Olsa | 7f50d06 | 2016-03-16 15:34:33 +0100 | [diff] [blame] | 2929 | |
| 2930 | if (ftrace_hash_rec_disable(ops, 1)) |
| 2931 | command |= FTRACE_UPDATE_CALLS; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 2932 | |
Namhyung Kim | a737e6d | 2014-06-12 23:56:12 +0900 | [diff] [blame] | 2933 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 2934 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2935 | if (saved_ftrace_func != ftrace_trace_function) { |
| 2936 | saved_ftrace_func = ftrace_trace_function; |
| 2937 | command |= FTRACE_UPDATE_TRACE_FUNC; |
| 2938 | } |
| 2939 | |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2940 | if (!command || !ftrace_enabled) { |
| 2941 | /* |
Steven Rostedt (VMware) | edb096e | 2017-09-01 12:18:28 -0400 | [diff] [blame] | 2942 | * If these are dynamic or per_cpu ops, they still |
| 2943 | * need their data freed. Since, function tracing is |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2944 | * not currently active, we can just free them |
| 2945 | * without synchronizing all CPUs. |
| 2946 | */ |
Peter Zijlstra | b3a8880 | 2017-10-11 09:45:32 +0200 | [diff] [blame] | 2947 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) |
Steven Rostedt (VMware) | edb096e | 2017-09-01 12:18:28 -0400 | [diff] [blame] | 2948 | goto free_ops; |
| 2949 | |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 2950 | return 0; |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2951 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2952 | |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2953 | /* |
| 2954 | * If the ops uses a trampoline, then it needs to be |
| 2955 | * tested first on update. |
| 2956 | */ |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2957 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2958 | removed_ops = ops; |
| 2959 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2960 | /* The trampoline logic checks the old hashes */ |
| 2961 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; |
| 2962 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; |
| 2963 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2964 | ftrace_run_update_code(command); |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2965 | |
Steven Rostedt (Red Hat) | 84bde62 | 2014-09-12 14:21:13 -0400 | [diff] [blame] | 2966 | /* |
| 2967 | * If there's no more ops registered with ftrace, run a |
| 2968 | * sanity check to make sure all rec flags are cleared. |
| 2969 | */ |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 2970 | if (rcu_dereference_protected(ftrace_ops_list, |
| 2971 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { |
Steven Rostedt (Red Hat) | 84bde62 | 2014-09-12 14:21:13 -0400 | [diff] [blame] | 2972 | struct ftrace_page *pg; |
| 2973 | struct dyn_ftrace *rec; |
| 2974 | |
| 2975 | do_for_each_ftrace_rec(pg, rec) { |
Alexei Starovoitov | 977c1f9 | 2016-11-07 15:14:20 -0800 | [diff] [blame] | 2976 | if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) |
Steven Rostedt (Red Hat) | 84bde62 | 2014-09-12 14:21:13 -0400 | [diff] [blame] | 2977 | pr_warn(" %pS flags:%lx\n", |
| 2978 | (void *)rec->ip, rec->flags); |
| 2979 | } while_for_each_ftrace_rec(); |
| 2980 | } |
| 2981 | |
Steven Rostedt (Red Hat) | fef5aee | 2014-07-24 12:25:47 -0400 | [diff] [blame] | 2982 | ops->old_hash.filter_hash = NULL; |
| 2983 | ops->old_hash.notrace_hash = NULL; |
| 2984 | |
| 2985 | removed_ops = NULL; |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 2986 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
Steven Rostedt (Red Hat) | 79922b8 | 2014-05-06 21:56:17 -0400 | [diff] [blame] | 2987 | |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2988 | /* |
| 2989 | * Dynamic ops may be freed, we must make sure that all |
| 2990 | * callers are done before leaving this function. |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 2991 | * The same goes for freeing the per_cpu data of the per_cpu |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2992 | * ops. |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 2993 | */ |
Peter Zijlstra | b3a8880 | 2017-10-11 09:45:32 +0200 | [diff] [blame] | 2994 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) { |
Steven Rostedt (VMware) | 0598e4f | 2017-04-06 10:28:12 -0400 | [diff] [blame] | 2995 | /* |
| 2996 | * We need to do a hard force of sched synchronization. |
| 2997 | * This is because we use preempt_disable() to do RCU, but |
| 2998 | * the function tracers can be called where RCU is not watching |
| 2999 | * (like before user_exit()). We can not rely on the RCU |
| 3000 | * infrastructure to do the synchronization, thus we must do it |
| 3001 | * ourselves. |
| 3002 | */ |
Paul E. McKenney | e5a971d | 2020-04-03 12:10:28 -0700 | [diff] [blame] | 3003 | synchronize_rcu_tasks_rude(); |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 3004 | |
Steven Rostedt (VMware) | 0598e4f | 2017-04-06 10:28:12 -0400 | [diff] [blame] | 3005 | /* |
Qiujun Huang | fdda88d | 2020-10-02 22:31:26 +0800 | [diff] [blame] | 3006 | * When the kernel is preemptive, tasks can be preempted |
Steven Rostedt (VMware) | 0598e4f | 2017-04-06 10:28:12 -0400 | [diff] [blame] | 3007 | * while on a ftrace trampoline. Just scheduling a task on |
| 3008 | * a CPU is not good enough to flush them. Calling |
Ingo Molnar | f2cc020 | 2021-03-23 18:49:35 +0100 | [diff] [blame] | 3009 | * synchronize_rcu_tasks() will wait for those tasks to |
Steven Rostedt (VMware) | 0598e4f | 2017-04-06 10:28:12 -0400 | [diff] [blame] | 3010 | * execute and either schedule voluntarily or enter user space. |
| 3011 | */ |
Thomas Gleixner | 30c9370 | 2019-07-26 23:19:40 +0200 | [diff] [blame] | 3012 | if (IS_ENABLED(CONFIG_PREEMPTION)) |
Steven Rostedt (VMware) | 0598e4f | 2017-04-06 10:28:12 -0400 | [diff] [blame] | 3013 | synchronize_rcu_tasks(); |
| 3014 | |
Steven Rostedt (VMware) | edb096e | 2017-09-01 12:18:28 -0400 | [diff] [blame] | 3015 | free_ops: |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 3016 | ftrace_trampoline_free(ops); |
Steven Rostedt (Red Hat) | a4c35ed2 | 2014-01-13 12:56:21 -0500 | [diff] [blame] | 3017 | } |
| 3018 | |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 3019 | return 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3020 | } |
| 3021 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 3022 | static void ftrace_startup_sysctl(void) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3023 | { |
Pratyush Anand | 1619dc3 | 2015-03-06 23:58:06 +0530 | [diff] [blame] | 3024 | int command; |
| 3025 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 3026 | if (unlikely(ftrace_disabled)) |
| 3027 | return; |
| 3028 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3029 | /* Force update next time */ |
| 3030 | saved_ftrace_func = NULL; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 3031 | /* ftrace_start_up is true if we want ftrace running */ |
Pratyush Anand | 1619dc3 | 2015-03-06 23:58:06 +0530 | [diff] [blame] | 3032 | if (ftrace_start_up) { |
| 3033 | command = FTRACE_UPDATE_CALLS; |
| 3034 | if (ftrace_graph_active) |
| 3035 | command |= FTRACE_START_FUNC_RET; |
Steven Rostedt (Red Hat) | 524a386 | 2015-03-06 19:55:13 -0500 | [diff] [blame] | 3036 | ftrace_startup_enable(command); |
Pratyush Anand | 1619dc3 | 2015-03-06 23:58:06 +0530 | [diff] [blame] | 3037 | } |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3038 | } |
| 3039 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 3040 | static void ftrace_shutdown_sysctl(void) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3041 | { |
Pratyush Anand | 1619dc3 | 2015-03-06 23:58:06 +0530 | [diff] [blame] | 3042 | int command; |
| 3043 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 3044 | if (unlikely(ftrace_disabled)) |
| 3045 | return; |
| 3046 | |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 3047 | /* ftrace_start_up is true if ftrace is running */ |
Pratyush Anand | 1619dc3 | 2015-03-06 23:58:06 +0530 | [diff] [blame] | 3048 | if (ftrace_start_up) { |
| 3049 | command = FTRACE_DISABLE_CALLS; |
| 3050 | if (ftrace_graph_active) |
| 3051 | command |= FTRACE_STOP_FUNC_RET; |
| 3052 | ftrace_run_update_code(command); |
| 3053 | } |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3054 | } |
| 3055 | |
Thomas Gleixner | a5a1d1c | 2016-12-21 20:32:01 +0100 | [diff] [blame] | 3056 | static u64 ftrace_update_time; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3057 | unsigned long ftrace_update_tot_cnt; |
Steven Rostedt (VMware) | da537f0 | 2019-10-01 14:38:07 -0400 | [diff] [blame] | 3058 | unsigned long ftrace_number_of_pages; |
| 3059 | unsigned long ftrace_number_of_groups; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3060 | |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3061 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
Steven Rostedt | f7bc8b6 | 2011-07-14 23:02:27 -0400 | [diff] [blame] | 3062 | { |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3063 | /* |
| 3064 | * Filter_hash being empty will default to trace module. |
| 3065 | * But notrace hash requires a test of individual module functions. |
| 3066 | */ |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3067 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
| 3068 | ftrace_hash_empty(ops->func_hash->notrace_hash); |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3069 | } |
Steven Rostedt | f7bc8b6 | 2011-07-14 23:02:27 -0400 | [diff] [blame] | 3070 | |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3071 | /* |
| 3072 | * Check if the current ops references the record. |
| 3073 | * |
| 3074 | * If the ops traces all functions, then it was already accounted for. |
| 3075 | * If the ops does not trace the current record function, skip it. |
| 3076 | * If the ops ignores the function via notrace filter, skip it. |
| 3077 | */ |
| 3078 | static inline bool |
| 3079 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) |
| 3080 | { |
| 3081 | /* If ops isn't enabled, ignore it */ |
| 3082 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) |
Gustavo A. R. Silva | 44ec3ec | 2018-08-01 20:00:56 -0500 | [diff] [blame] | 3083 | return false; |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3084 | |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 3085 | /* If ops traces all then it includes this function */ |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3086 | if (ops_traces_mod(ops)) |
Gustavo A. R. Silva | 44ec3ec | 2018-08-01 20:00:56 -0500 | [diff] [blame] | 3087 | return true; |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3088 | |
| 3089 | /* The function must be in the filter */ |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3090 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
Steven Rostedt (VMware) | 2b2c279 | 2017-02-01 15:37:07 -0500 | [diff] [blame] | 3091 | !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) |
Gustavo A. R. Silva | 44ec3ec | 2018-08-01 20:00:56 -0500 | [diff] [blame] | 3092 | return false; |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3093 | |
| 3094 | /* If in notrace hash, we ignore it too */ |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3095 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
Gustavo A. R. Silva | 44ec3ec | 2018-08-01 20:00:56 -0500 | [diff] [blame] | 3096 | return false; |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3097 | |
Gustavo A. R. Silva | 44ec3ec | 2018-08-01 20:00:56 -0500 | [diff] [blame] | 3098 | return true; |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3099 | } |
| 3100 | |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 3101 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3102 | { |
Ilya Leoshkevich | 67ccddf | 2021-07-28 23:25:45 +0200 | [diff] [blame] | 3103 | bool init_nop = ftrace_need_init_nop(); |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3104 | struct ftrace_page *pg; |
Lai Jiangshan | e94142a | 2009-03-13 17:51:27 +0800 | [diff] [blame] | 3105 | struct dyn_ftrace *p; |
Thomas Gleixner | a5a1d1c | 2016-12-21 20:32:01 +0100 | [diff] [blame] | 3106 | u64 start, stop; |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 3107 | unsigned long update_cnt = 0; |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 3108 | unsigned long rec_flags = 0; |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3109 | int i; |
Steven Rostedt | f7bc8b6 | 2011-07-14 23:02:27 -0400 | [diff] [blame] | 3110 | |
Ingo Molnar | 750ed1a | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 3111 | start = ftrace_now(raw_smp_processor_id()); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3112 | |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 3113 | /* |
| 3114 | * When a module is loaded, this function is called to convert |
| 3115 | * the calls to mcount in its text to nops, and also to create |
| 3116 | * an entry in the ftrace data. Now, if ftrace is activated |
| 3117 | * after this call, but before the module sets its text to |
| 3118 | * read-only, the modification of enabling ftrace can fail if |
| 3119 | * the read-only is done while ftrace is converting the calls. |
| 3120 | * To prevent this, the module's records are set as disabled |
| 3121 | * and will be enabled after the call to set the module's text |
| 3122 | * to read-only. |
| 3123 | */ |
| 3124 | if (mod) |
| 3125 | rec_flags |= FTRACE_FL_DISABLED; |
| 3126 | |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 3127 | for (pg = new_pgs; pg; pg = pg->next) { |
Abhishek Sagar | f22f9a8 | 2008-06-21 23:50:29 +0530 | [diff] [blame] | 3128 | |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3129 | for (i = 0; i < pg->index; i++) { |
Steven Rostedt (Red Hat) | 8c4f3c3 | 2013-07-30 00:04:32 -0400 | [diff] [blame] | 3130 | |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3131 | /* If something went wrong, bail without enabling anything */ |
| 3132 | if (unlikely(ftrace_disabled)) |
| 3133 | return -1; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3134 | |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3135 | p = &pg->records[i]; |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 3136 | p->flags = rec_flags; |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame] | 3137 | |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3138 | /* |
| 3139 | * Do the initial record conversion from mcount jump |
| 3140 | * to the NOP instructions. |
| 3141 | */ |
Ilya Leoshkevich | 67ccddf | 2021-07-28 23:25:45 +0200 | [diff] [blame] | 3142 | if (init_nop && !ftrace_nop_initialize(mod, p)) |
Steven Rostedt | 85ae32a | 2011-12-16 16:30:31 -0500 | [diff] [blame] | 3143 | break; |
Jiri Olsa | 5cb084b | 2009-10-13 16:33:53 -0400 | [diff] [blame] | 3144 | |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 3145 | update_cnt++; |
Jiri Olsa | 5cb084b | 2009-10-13 16:33:53 -0400 | [diff] [blame] | 3146 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3147 | } |
| 3148 | |
Ingo Molnar | 750ed1a | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 3149 | stop = ftrace_now(raw_smp_processor_id()); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3150 | ftrace_update_time = stop - start; |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 3151 | ftrace_update_tot_cnt += update_cnt; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3152 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 3153 | return 0; |
| 3154 | } |
| 3155 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3156 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3157 | { |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3158 | int order; |
Steven Rostedt (VMware) | 7ba031e | 2020-10-05 20:37:41 -0400 | [diff] [blame] | 3159 | int pages; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3160 | int cnt; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3161 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3162 | if (WARN_ON(!count)) |
| 3163 | return -EINVAL; |
| 3164 | |
Steven Rostedt (VMware) | ceaaa12 | 2021-04-01 16:40:32 -0400 | [diff] [blame] | 3165 | /* We want to fill as much as possible, with no empty pages */ |
Wei Yang | b40c6ea | 2020-08-31 11:11:02 +0800 | [diff] [blame] | 3166 | pages = DIV_ROUND_UP(count, ENTRIES_PER_PAGE); |
Steven Rostedt (VMware) | ceaaa12 | 2021-04-01 16:40:32 -0400 | [diff] [blame] | 3167 | order = fls(pages) - 1; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3168 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3169 | again: |
| 3170 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); |
| 3171 | |
| 3172 | if (!pg->records) { |
| 3173 | /* if we can't allocate this size, try something smaller */ |
| 3174 | if (!order) |
| 3175 | return -ENOMEM; |
| 3176 | order >>= 1; |
| 3177 | goto again; |
| 3178 | } |
| 3179 | |
Steven Rostedt (VMware) | da537f0 | 2019-10-01 14:38:07 -0400 | [diff] [blame] | 3180 | ftrace_number_of_pages += 1 << order; |
| 3181 | ftrace_number_of_groups++; |
| 3182 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3183 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 3184 | pg->order = order; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3185 | |
| 3186 | if (cnt > count) |
| 3187 | cnt = count; |
| 3188 | |
| 3189 | return cnt; |
| 3190 | } |
| 3191 | |
| 3192 | static struct ftrace_page * |
| 3193 | ftrace_allocate_pages(unsigned long num_to_init) |
| 3194 | { |
| 3195 | struct ftrace_page *start_pg; |
| 3196 | struct ftrace_page *pg; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3197 | int cnt; |
| 3198 | |
| 3199 | if (!num_to_init) |
Hariprasad Kelam | 9efb85c | 2019-03-24 00:05:23 +0530 | [diff] [blame] | 3200 | return NULL; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3201 | |
| 3202 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); |
| 3203 | if (!pg) |
| 3204 | return NULL; |
| 3205 | |
| 3206 | /* |
| 3207 | * Try to allocate as much as possible in one continues |
| 3208 | * location that fills in all of the space. We want to |
| 3209 | * waste as little space as possible. |
| 3210 | */ |
| 3211 | for (;;) { |
| 3212 | cnt = ftrace_allocate_records(pg, num_to_init); |
| 3213 | if (cnt < 0) |
| 3214 | goto free_pages; |
| 3215 | |
| 3216 | num_to_init -= cnt; |
| 3217 | if (!num_to_init) |
| 3218 | break; |
| 3219 | |
| 3220 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
| 3221 | if (!pg->next) |
| 3222 | goto free_pages; |
| 3223 | |
| 3224 | pg = pg->next; |
| 3225 | } |
| 3226 | |
| 3227 | return start_pg; |
| 3228 | |
| 3229 | free_pages: |
Namhyung Kim | 1f61be00 | 2014-06-11 17:06:53 +0900 | [diff] [blame] | 3230 | pg = start_pg; |
| 3231 | while (pg) { |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 3232 | if (pg->records) { |
| 3233 | free_pages((unsigned long)pg->records, pg->order); |
| 3234 | ftrace_number_of_pages -= 1 << pg->order; |
| 3235 | } |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3236 | start_pg = pg->next; |
| 3237 | kfree(pg); |
| 3238 | pg = start_pg; |
Steven Rostedt (VMware) | da537f0 | 2019-10-01 14:38:07 -0400 | [diff] [blame] | 3239 | ftrace_number_of_groups--; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 3240 | } |
| 3241 | pr_info("ftrace: FAILED to allocate memory for functions\n"); |
| 3242 | return NULL; |
| 3243 | } |
| 3244 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3245 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
| 3246 | |
| 3247 | struct ftrace_iterator { |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3248 | loff_t pos; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3249 | loff_t func_pos; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3250 | loff_t mod_pos; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3251 | struct ftrace_page *pg; |
| 3252 | struct dyn_ftrace *func; |
| 3253 | struct ftrace_func_probe *probe; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3254 | struct ftrace_func_entry *probe_entry; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3255 | struct trace_parser parser; |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3256 | struct ftrace_hash *hash; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 3257 | struct ftrace_ops *ops; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3258 | struct trace_array *tr; |
| 3259 | struct list_head *mod_list; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3260 | int pidx; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3261 | int idx; |
| 3262 | unsigned flags; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3263 | }; |
| 3264 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 3265 | static void * |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3266 | t_probe_next(struct seq_file *m, loff_t *pos) |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3267 | { |
| 3268 | struct ftrace_iterator *iter = m->private; |
Steven Rostedt (VMware) | d2afd57a | 2017-04-20 11:31:35 -0400 | [diff] [blame] | 3269 | struct trace_array *tr = iter->ops->private; |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 3270 | struct list_head *func_probes; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3271 | struct ftrace_hash *hash; |
| 3272 | struct list_head *next; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3273 | struct hlist_node *hnd = NULL; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3274 | struct hlist_head *hhd; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3275 | int size; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3276 | |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3277 | (*pos)++; |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3278 | iter->pos = *pos; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3279 | |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 3280 | if (!tr) |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3281 | return NULL; |
| 3282 | |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 3283 | func_probes = &tr->func_probes; |
| 3284 | if (list_empty(func_probes)) |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3285 | return NULL; |
| 3286 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3287 | if (!iter->probe) { |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 3288 | next = func_probes->next; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 3289 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3290 | } |
| 3291 | |
| 3292 | if (iter->probe_entry) |
| 3293 | hnd = &iter->probe_entry->hlist; |
| 3294 | |
| 3295 | hash = iter->probe->ops.func_hash->filter_hash; |
Naveen N. Rao | 7bd4664 | 2019-07-04 20:04:41 +0530 | [diff] [blame] | 3296 | |
Steven Rostedt (VMware) | 372e0d0 | 2019-08-30 16:30:01 -0400 | [diff] [blame] | 3297 | /* |
| 3298 | * A probe being registered may temporarily have an empty hash |
| 3299 | * and it's at the end of the func_probes list. |
| 3300 | */ |
| 3301 | if (!hash || hash == EMPTY_HASH) |
Naveen N. Rao | 7bd4664 | 2019-07-04 20:04:41 +0530 | [diff] [blame] | 3302 | return NULL; |
| 3303 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3304 | size = 1 << hash->size_bits; |
| 3305 | |
| 3306 | retry: |
| 3307 | if (iter->pidx >= size) { |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 3308 | if (iter->probe->list.next == func_probes) |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3309 | return NULL; |
| 3310 | next = iter->probe->list.next; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 3311 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3312 | hash = iter->probe->ops.func_hash->filter_hash; |
| 3313 | size = 1 << hash->size_bits; |
| 3314 | iter->pidx = 0; |
| 3315 | } |
| 3316 | |
| 3317 | hhd = &hash->buckets[iter->pidx]; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3318 | |
| 3319 | if (hlist_empty(hhd)) { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3320 | iter->pidx++; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3321 | hnd = NULL; |
| 3322 | goto retry; |
| 3323 | } |
| 3324 | |
| 3325 | if (!hnd) |
| 3326 | hnd = hhd->first; |
| 3327 | else { |
| 3328 | hnd = hnd->next; |
| 3329 | if (!hnd) { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3330 | iter->pidx++; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3331 | goto retry; |
| 3332 | } |
| 3333 | } |
| 3334 | |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3335 | if (WARN_ON_ONCE(!hnd)) |
| 3336 | return NULL; |
| 3337 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3338 | iter->probe_entry = hlist_entry(hnd, struct ftrace_func_entry, hlist); |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3339 | |
| 3340 | return iter; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3341 | } |
| 3342 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3343 | static void *t_probe_start(struct seq_file *m, loff_t *pos) |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3344 | { |
| 3345 | struct ftrace_iterator *iter = m->private; |
| 3346 | void *p = NULL; |
Li Zefan | d82d624 | 2009-06-24 09:54:54 +0800 | [diff] [blame] | 3347 | loff_t l; |
| 3348 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3349 | if (!(iter->flags & FTRACE_ITER_DO_PROBES)) |
Steven Rostedt | 69a3083 | 2011-12-19 15:21:16 -0500 | [diff] [blame] | 3350 | return NULL; |
| 3351 | |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3352 | if (iter->mod_pos > *pos) |
Steven Rostedt | 2bccfff | 2010-09-09 08:43:22 -0400 | [diff] [blame] | 3353 | return NULL; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3354 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3355 | iter->probe = NULL; |
| 3356 | iter->probe_entry = NULL; |
| 3357 | iter->pidx = 0; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3358 | for (l = 0; l <= (*pos - iter->mod_pos); ) { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3359 | p = t_probe_next(m, &l); |
Li Zefan | d82d624 | 2009-06-24 09:54:54 +0800 | [diff] [blame] | 3360 | if (!p) |
| 3361 | break; |
| 3362 | } |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3363 | if (!p) |
| 3364 | return NULL; |
| 3365 | |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3366 | /* Only set this if we have an item */ |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3367 | iter->flags |= FTRACE_ITER_PROBE; |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3368 | |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3369 | return iter; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3370 | } |
| 3371 | |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3372 | static int |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3373 | t_probe_show(struct seq_file *m, struct ftrace_iterator *iter) |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3374 | { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3375 | struct ftrace_func_entry *probe_entry; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 3376 | struct ftrace_probe_ops *probe_ops; |
| 3377 | struct ftrace_func_probe *probe; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3378 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3379 | probe = iter->probe; |
| 3380 | probe_entry = iter->probe_entry; |
| 3381 | |
| 3382 | if (WARN_ON_ONCE(!probe || !probe_entry)) |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3383 | return -EIO; |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3384 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 3385 | probe_ops = probe->probe_ops; |
Steven Rostedt | 809dcf2 | 2009-02-16 23:06:01 -0500 | [diff] [blame] | 3386 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 3387 | if (probe_ops->print) |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 3388 | return probe_ops->print(m, probe_entry->ip, probe_ops, probe->data); |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3389 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 3390 | seq_printf(m, "%ps:%ps\n", (void *)probe_entry->ip, |
| 3391 | (void *)probe_ops->func); |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3392 | |
| 3393 | return 0; |
| 3394 | } |
| 3395 | |
| 3396 | static void * |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3397 | t_mod_next(struct seq_file *m, loff_t *pos) |
| 3398 | { |
| 3399 | struct ftrace_iterator *iter = m->private; |
| 3400 | struct trace_array *tr = iter->tr; |
| 3401 | |
| 3402 | (*pos)++; |
| 3403 | iter->pos = *pos; |
| 3404 | |
| 3405 | iter->mod_list = iter->mod_list->next; |
| 3406 | |
| 3407 | if (iter->mod_list == &tr->mod_trace || |
| 3408 | iter->mod_list == &tr->mod_notrace) { |
| 3409 | iter->flags &= ~FTRACE_ITER_MOD; |
| 3410 | return NULL; |
| 3411 | } |
| 3412 | |
| 3413 | iter->mod_pos = *pos; |
| 3414 | |
| 3415 | return iter; |
| 3416 | } |
| 3417 | |
| 3418 | static void *t_mod_start(struct seq_file *m, loff_t *pos) |
| 3419 | { |
| 3420 | struct ftrace_iterator *iter = m->private; |
| 3421 | void *p = NULL; |
| 3422 | loff_t l; |
| 3423 | |
| 3424 | if (iter->func_pos > *pos) |
| 3425 | return NULL; |
| 3426 | |
| 3427 | iter->mod_pos = iter->func_pos; |
| 3428 | |
| 3429 | /* probes are only available if tr is set */ |
| 3430 | if (!iter->tr) |
| 3431 | return NULL; |
| 3432 | |
| 3433 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
| 3434 | p = t_mod_next(m, &l); |
| 3435 | if (!p) |
| 3436 | break; |
| 3437 | } |
| 3438 | if (!p) { |
| 3439 | iter->flags &= ~FTRACE_ITER_MOD; |
| 3440 | return t_probe_start(m, pos); |
| 3441 | } |
| 3442 | |
| 3443 | /* Only set this if we have an item */ |
| 3444 | iter->flags |= FTRACE_ITER_MOD; |
| 3445 | |
| 3446 | return iter; |
| 3447 | } |
| 3448 | |
| 3449 | static int |
| 3450 | t_mod_show(struct seq_file *m, struct ftrace_iterator *iter) |
| 3451 | { |
| 3452 | struct ftrace_mod_load *ftrace_mod; |
| 3453 | struct trace_array *tr = iter->tr; |
| 3454 | |
| 3455 | if (WARN_ON_ONCE(!iter->mod_list) || |
| 3456 | iter->mod_list == &tr->mod_trace || |
| 3457 | iter->mod_list == &tr->mod_notrace) |
| 3458 | return -EIO; |
| 3459 | |
| 3460 | ftrace_mod = list_entry(iter->mod_list, struct ftrace_mod_load, list); |
| 3461 | |
| 3462 | if (ftrace_mod->func) |
| 3463 | seq_printf(m, "%s", ftrace_mod->func); |
| 3464 | else |
| 3465 | seq_putc(m, '*'); |
| 3466 | |
| 3467 | seq_printf(m, ":mod:%s\n", ftrace_mod->module); |
| 3468 | |
| 3469 | return 0; |
| 3470 | } |
| 3471 | |
| 3472 | static void * |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3473 | t_func_next(struct seq_file *m, loff_t *pos) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3474 | { |
| 3475 | struct ftrace_iterator *iter = m->private; |
| 3476 | struct dyn_ftrace *rec = NULL; |
| 3477 | |
| 3478 | (*pos)++; |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3479 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3480 | retry: |
| 3481 | if (iter->idx >= iter->pg->index) { |
| 3482 | if (iter->pg->next) { |
| 3483 | iter->pg = iter->pg->next; |
| 3484 | iter->idx = 0; |
| 3485 | goto retry; |
| 3486 | } |
| 3487 | } else { |
| 3488 | rec = &iter->pg->records[iter->idx++]; |
Steven Rostedt (VMware) | c20489d | 2017-03-29 14:55:49 -0400 | [diff] [blame] | 3489 | if (((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
| 3490 | !ftrace_lookup_ip(iter->hash, rec->ip)) || |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3491 | |
| 3492 | ((iter->flags & FTRACE_ITER_ENABLED) && |
Steven Rostedt (Red Hat) | 23ea9c4 | 2013-05-09 19:31:48 -0400 | [diff] [blame] | 3493 | !(rec->flags & FTRACE_FL_ENABLED))) { |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3494 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3495 | rec = NULL; |
| 3496 | goto retry; |
| 3497 | } |
| 3498 | } |
| 3499 | |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3500 | if (!rec) |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3501 | return NULL; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3502 | |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3503 | iter->pos = iter->func_pos = *pos; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3504 | iter->func = rec; |
| 3505 | |
| 3506 | return iter; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3507 | } |
| 3508 | |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3509 | static void * |
| 3510 | t_next(struct seq_file *m, void *v, loff_t *pos) |
| 3511 | { |
| 3512 | struct ftrace_iterator *iter = m->private; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3513 | loff_t l = *pos; /* t_probe_start() must use original pos */ |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3514 | void *ret; |
| 3515 | |
| 3516 | if (unlikely(ftrace_disabled)) |
| 3517 | return NULL; |
| 3518 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3519 | if (iter->flags & FTRACE_ITER_PROBE) |
| 3520 | return t_probe_next(m, pos); |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3521 | |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3522 | if (iter->flags & FTRACE_ITER_MOD) |
| 3523 | return t_mod_next(m, pos); |
| 3524 | |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3525 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3526 | /* next must increment pos, and t_probe_start does not */ |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3527 | (*pos)++; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3528 | return t_mod_start(m, &l); |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3529 | } |
| 3530 | |
| 3531 | ret = t_func_next(m, pos); |
| 3532 | |
| 3533 | if (!ret) |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3534 | return t_mod_start(m, &l); |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3535 | |
| 3536 | return ret; |
| 3537 | } |
| 3538 | |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3539 | static void reset_iter_read(struct ftrace_iterator *iter) |
| 3540 | { |
| 3541 | iter->pos = 0; |
| 3542 | iter->func_pos = 0; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3543 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_PROBE | FTRACE_ITER_MOD); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3544 | } |
| 3545 | |
| 3546 | static void *t_start(struct seq_file *m, loff_t *pos) |
| 3547 | { |
| 3548 | struct ftrace_iterator *iter = m->private; |
| 3549 | void *p = NULL; |
Li Zefan | 694ce0a | 2009-06-24 09:54:19 +0800 | [diff] [blame] | 3550 | loff_t l; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3551 | |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3552 | mutex_lock(&ftrace_lock); |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 3553 | |
| 3554 | if (unlikely(ftrace_disabled)) |
| 3555 | return NULL; |
| 3556 | |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3557 | /* |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3558 | * If an lseek was done, then reset and start from beginning. |
| 3559 | */ |
| 3560 | if (*pos < iter->pos) |
| 3561 | reset_iter_read(iter); |
| 3562 | |
| 3563 | /* |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3564 | * For set_ftrace_filter reading, if we have the filter |
| 3565 | * off, we can short cut and just print out that all |
| 3566 | * functions are enabled. |
| 3567 | */ |
Steven Rostedt (VMware) | c20489d | 2017-03-29 14:55:49 -0400 | [diff] [blame] | 3568 | if ((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
| 3569 | ftrace_hash_empty(iter->hash)) { |
Steven Rostedt (VMware) | 43ff926 | 2017-03-30 16:51:43 -0400 | [diff] [blame] | 3570 | iter->func_pos = 1; /* Account for the message */ |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3571 | if (*pos > 0) |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3572 | return t_mod_start(m, pos); |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3573 | iter->flags |= FTRACE_ITER_PRINTALL; |
Chris Wright | df09162 | 2010-09-09 16:34:59 -0700 | [diff] [blame] | 3574 | /* reset in case of seek/pread */ |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3575 | iter->flags &= ~FTRACE_ITER_PROBE; |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3576 | return iter; |
| 3577 | } |
| 3578 | |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3579 | if (iter->flags & FTRACE_ITER_MOD) |
| 3580 | return t_mod_start(m, pos); |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3581 | |
Steven Rostedt | 98c4fd0 | 2010-09-10 11:47:43 -0400 | [diff] [blame] | 3582 | /* |
| 3583 | * Unfortunately, we need to restart at ftrace_pages_start |
| 3584 | * every time we let go of the ftrace_mutex. This is because |
| 3585 | * those pointers can change without the lock. |
| 3586 | */ |
Li Zefan | 694ce0a | 2009-06-24 09:54:19 +0800 | [diff] [blame] | 3587 | iter->pg = ftrace_pages_start; |
| 3588 | iter->idx = 0; |
| 3589 | for (l = 0; l <= *pos; ) { |
Steven Rostedt (VMware) | 5bd8462 | 2017-03-29 22:45:18 -0400 | [diff] [blame] | 3590 | p = t_func_next(m, &l); |
Li Zefan | 694ce0a | 2009-06-24 09:54:19 +0800 | [diff] [blame] | 3591 | if (!p) |
| 3592 | break; |
Liming Wang | 50cdaf0 | 2008-11-28 12:13:21 +0800 | [diff] [blame] | 3593 | } |
walimis | 5821e1b | 2008-11-15 15:19:06 +0800 | [diff] [blame] | 3594 | |
Steven Rostedt | 69a3083 | 2011-12-19 15:21:16 -0500 | [diff] [blame] | 3595 | if (!p) |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3596 | return t_mod_start(m, pos); |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3597 | |
| 3598 | return iter; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3599 | } |
| 3600 | |
| 3601 | static void t_stop(struct seq_file *m, void *p) |
| 3602 | { |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3603 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3604 | } |
| 3605 | |
Steven Rostedt (Red Hat) | 15d5b02 | 2014-07-03 14:51:36 -0400 | [diff] [blame] | 3606 | void * __weak |
| 3607 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) |
| 3608 | { |
| 3609 | return NULL; |
| 3610 | } |
| 3611 | |
| 3612 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, |
| 3613 | struct dyn_ftrace *rec) |
| 3614 | { |
| 3615 | void *ptr; |
| 3616 | |
| 3617 | ptr = arch_ftrace_trampoline_func(ops, rec); |
| 3618 | if (ptr) |
| 3619 | seq_printf(m, " ->%pS", ptr); |
| 3620 | } |
| 3621 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3622 | static int t_show(struct seq_file *m, void *v) |
| 3623 | { |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3624 | struct ftrace_iterator *iter = m->private; |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3625 | struct dyn_ftrace *rec; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3626 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3627 | if (iter->flags & FTRACE_ITER_PROBE) |
| 3628 | return t_probe_show(m, iter); |
Steven Rostedt | 8fc0c70 | 2009-02-16 15:28:00 -0500 | [diff] [blame] | 3629 | |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3630 | if (iter->flags & FTRACE_ITER_MOD) |
| 3631 | return t_mod_show(m, iter); |
| 3632 | |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3633 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
Namhyung Kim | 8c006cf | 2014-06-13 16:24:06 +0900 | [diff] [blame] | 3634 | if (iter->flags & FTRACE_ITER_NOTRACE) |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 3635 | seq_puts(m, "#### no functions disabled ####\n"); |
Namhyung Kim | 8c006cf | 2014-06-13 16:24:06 +0900 | [diff] [blame] | 3636 | else |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 3637 | seq_puts(m, "#### all functions enabled ####\n"); |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 3638 | return 0; |
| 3639 | } |
| 3640 | |
Steven Rostedt | 4aeb696 | 2010-09-09 10:00:28 -0400 | [diff] [blame] | 3641 | rec = iter->func; |
| 3642 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3643 | if (!rec) |
| 3644 | return 0; |
| 3645 | |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3646 | seq_printf(m, "%ps", (void *)rec->ip); |
Steven Rostedt (Red Hat) | 9674b2f | 2014-05-09 16:54:59 -0400 | [diff] [blame] | 3647 | if (iter->flags & FTRACE_ITER_ENABLED) { |
Steven Rostedt (Red Hat) | 030f4e1 | 2015-12-01 12:24:45 -0500 | [diff] [blame] | 3648 | struct ftrace_ops *ops; |
Steven Rostedt (Red Hat) | 15d5b02 | 2014-07-03 14:51:36 -0400 | [diff] [blame] | 3649 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 3650 | seq_printf(m, " (%ld)%s%s%s", |
Steven Rostedt (Red Hat) | 0376bde | 2014-05-07 13:46:45 -0400 | [diff] [blame] | 3651 | ftrace_rec_count(rec), |
Masami Hiramatsu | f8b8be8 | 2014-11-21 05:25:16 -0500 | [diff] [blame] | 3652 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 3653 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ", |
| 3654 | rec->flags & FTRACE_FL_DIRECT ? " D" : " "); |
Steven Rostedt (Red Hat) | 9674b2f | 2014-05-09 16:54:59 -0400 | [diff] [blame] | 3655 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
Steven Rostedt (Red Hat) | 5fecaa0 | 2014-07-24 16:00:31 -0400 | [diff] [blame] | 3656 | ops = ftrace_find_tramp_ops_any(rec); |
Steven Rostedt (Red Hat) | 39daa7b | 2015-11-25 15:12:38 -0500 | [diff] [blame] | 3657 | if (ops) { |
| 3658 | do { |
| 3659 | seq_printf(m, "\ttramp: %pS (%pS)", |
| 3660 | (void *)ops->trampoline, |
| 3661 | (void *)ops->func); |
Steven Rostedt (Red Hat) | 030f4e1 | 2015-12-01 12:24:45 -0500 | [diff] [blame] | 3662 | add_trampoline_func(m, ops, rec); |
Steven Rostedt (Red Hat) | 39daa7b | 2015-11-25 15:12:38 -0500 | [diff] [blame] | 3663 | ops = ftrace_find_tramp_ops_next(rec, ops); |
| 3664 | } while (ops); |
| 3665 | } else |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 3666 | seq_puts(m, "\ttramp: ERROR!"); |
Steven Rostedt (Red Hat) | 030f4e1 | 2015-12-01 12:24:45 -0500 | [diff] [blame] | 3667 | } else { |
| 3668 | add_trampoline_func(m, NULL, rec); |
Steven Rostedt (Red Hat) | 9674b2f | 2014-05-09 16:54:59 -0400 | [diff] [blame] | 3669 | } |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 3670 | if (rec->flags & FTRACE_FL_DIRECT) { |
| 3671 | unsigned long direct; |
| 3672 | |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 3673 | direct = ftrace_find_rec_direct(rec->ip); |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 3674 | if (direct) |
| 3675 | seq_printf(m, "\n\tdirect-->%pS", (void *)direct); |
| 3676 | } |
Kaitao Cheng | 026bb84 | 2020-05-29 22:12:14 +0800 | [diff] [blame] | 3677 | } |
Steven Rostedt (Red Hat) | 9674b2f | 2014-05-09 16:54:59 -0400 | [diff] [blame] | 3678 | |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 3679 | seq_putc(m, '\n'); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3680 | |
| 3681 | return 0; |
| 3682 | } |
| 3683 | |
James Morris | 88e9d34 | 2009-09-22 16:43:43 -0700 | [diff] [blame] | 3684 | static const struct seq_operations show_ftrace_seq_ops = { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3685 | .start = t_start, |
| 3686 | .next = t_next, |
| 3687 | .stop = t_stop, |
| 3688 | .show = t_show, |
| 3689 | }; |
| 3690 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 3691 | static int |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3692 | ftrace_avail_open(struct inode *inode, struct file *file) |
| 3693 | { |
| 3694 | struct ftrace_iterator *iter; |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 3695 | int ret; |
| 3696 | |
| 3697 | ret = security_locked_down(LOCKDOWN_TRACEFS); |
| 3698 | if (ret) |
| 3699 | return ret; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3700 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 3701 | if (unlikely(ftrace_disabled)) |
| 3702 | return -ENODEV; |
| 3703 | |
Jiri Olsa | 50e18b9 | 2012-04-25 10:23:39 +0200 | [diff] [blame] | 3704 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
Steven Rostedt (VMware) | c1bc591 | 2017-03-29 11:38:13 -0400 | [diff] [blame] | 3705 | if (!iter) |
| 3706 | return -ENOMEM; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3707 | |
Steven Rostedt (VMware) | c1bc591 | 2017-03-29 11:38:13 -0400 | [diff] [blame] | 3708 | iter->pg = ftrace_pages_start; |
| 3709 | iter->ops = &global_ops; |
| 3710 | |
| 3711 | return 0; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3712 | } |
| 3713 | |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3714 | static int |
| 3715 | ftrace_enabled_open(struct inode *inode, struct file *file) |
| 3716 | { |
| 3717 | struct ftrace_iterator *iter; |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3718 | |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 3719 | /* |
| 3720 | * This shows us what functions are currently being |
| 3721 | * traced and by what. Not sure if we want lockdown |
| 3722 | * to hide such critical information for an admin. |
| 3723 | * Although, perhaps it can show information we don't |
| 3724 | * want people to see, but if something is tracing |
| 3725 | * something, we probably want to know about it. |
| 3726 | */ |
| 3727 | |
Jiri Olsa | 50e18b9 | 2012-04-25 10:23:39 +0200 | [diff] [blame] | 3728 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
Steven Rostedt (VMware) | c1bc591 | 2017-03-29 11:38:13 -0400 | [diff] [blame] | 3729 | if (!iter) |
| 3730 | return -ENOMEM; |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3731 | |
Steven Rostedt (VMware) | c1bc591 | 2017-03-29 11:38:13 -0400 | [diff] [blame] | 3732 | iter->pg = ftrace_pages_start; |
| 3733 | iter->flags = FTRACE_ITER_ENABLED; |
| 3734 | iter->ops = &global_ops; |
| 3735 | |
| 3736 | return 0; |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 3737 | } |
| 3738 | |
Steven Rostedt | fc13cb0 | 2011-12-19 14:41:25 -0500 | [diff] [blame] | 3739 | /** |
| 3740 | * ftrace_regex_open - initialize function tracer filter files |
| 3741 | * @ops: The ftrace_ops that hold the hash filters |
| 3742 | * @flag: The type of filter to process |
| 3743 | * @inode: The inode, usually passed in to your open routine |
| 3744 | * @file: The file, usually passed in to your open routine |
| 3745 | * |
| 3746 | * ftrace_regex_open() initializes the filter files for the |
| 3747 | * @ops. Depending on @flag it may process the filter hash or |
| 3748 | * the notrace hash of @ops. With this called from the open |
| 3749 | * routine, you can use ftrace_filter_write() for the write |
| 3750 | * routine if @flag has FTRACE_ITER_FILTER set, or |
| 3751 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. |
Steven Rostedt (Red Hat) | 098c879e | 2013-12-21 17:39:40 -0500 | [diff] [blame] | 3752 | * tracing_lseek() should be used as the lseek routine, and |
Steven Rostedt | fc13cb0 | 2011-12-19 14:41:25 -0500 | [diff] [blame] | 3753 | * release must call ftrace_regex_release(). |
| 3754 | */ |
| 3755 | int |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 3756 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3757 | struct inode *inode, struct file *file) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3758 | { |
| 3759 | struct ftrace_iterator *iter; |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 3760 | struct ftrace_hash *hash; |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3761 | struct list_head *mod_head; |
| 3762 | struct trace_array *tr = ops->private; |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 3763 | int ret = -ENOMEM; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3764 | |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 3765 | ftrace_ops_init(ops); |
| 3766 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 3767 | if (unlikely(ftrace_disabled)) |
| 3768 | return -ENODEV; |
| 3769 | |
Steven Rostedt (VMware) | 8530dec | 2019-10-11 17:39:57 -0400 | [diff] [blame] | 3770 | if (tracing_check_open_get_tr(tr)) |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 3771 | return -ENODEV; |
| 3772 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3773 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
| 3774 | if (!iter) |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 3775 | goto out; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3776 | |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 3777 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) |
| 3778 | goto out; |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 3779 | |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 3780 | iter->ops = ops; |
| 3781 | iter->flags = flag; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3782 | iter->tr = tr; |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 3783 | |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3784 | mutex_lock(&ops->func_hash->regex_lock); |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 3785 | |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3786 | if (flag & FTRACE_ITER_NOTRACE) { |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3787 | hash = ops->func_hash->notrace_hash; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3788 | mod_head = tr ? &tr->mod_notrace : NULL; |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3789 | } else { |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3790 | hash = ops->func_hash->filter_hash; |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3791 | mod_head = tr ? &tr->mod_trace : NULL; |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3792 | } |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 3793 | |
Steven Rostedt (VMware) | 5985ea8 | 2017-06-23 16:05:11 -0400 | [diff] [blame] | 3794 | iter->mod_list = mod_head; |
| 3795 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 3796 | if (file->f_mode & FMODE_WRITE) { |
Namhyung Kim | ef2fbe1 | 2014-06-11 17:06:54 +0900 | [diff] [blame] | 3797 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
| 3798 | |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3799 | if (file->f_flags & O_TRUNC) { |
Namhyung Kim | ef2fbe1 | 2014-06-11 17:06:54 +0900 | [diff] [blame] | 3800 | iter->hash = alloc_ftrace_hash(size_bits); |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3801 | clear_ftrace_mod_list(mod_head); |
| 3802 | } else { |
Namhyung Kim | ef2fbe1 | 2014-06-11 17:06:54 +0900 | [diff] [blame] | 3803 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 3804 | } |
Namhyung Kim | ef2fbe1 | 2014-06-11 17:06:54 +0900 | [diff] [blame] | 3805 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 3806 | if (!iter->hash) { |
| 3807 | trace_parser_put(&iter->parser); |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 3808 | goto out_unlock; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 3809 | } |
Steven Rostedt (VMware) | c20489d | 2017-03-29 14:55:49 -0400 | [diff] [blame] | 3810 | } else |
| 3811 | iter->hash = hash; |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3812 | |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 3813 | ret = 0; |
| 3814 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3815 | if (file->f_mode & FMODE_READ) { |
| 3816 | iter->pg = ftrace_pages_start; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3817 | |
| 3818 | ret = seq_open(file, &show_ftrace_seq_ops); |
| 3819 | if (!ret) { |
| 3820 | struct seq_file *m = file->private_data; |
| 3821 | m->private = iter; |
Li Zefan | 79fe249 | 2009-09-22 13:54:28 +0800 | [diff] [blame] | 3822 | } else { |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 3823 | /* Failed */ |
| 3824 | free_ftrace_hash(iter->hash); |
Li Zefan | 79fe249 | 2009-09-22 13:54:28 +0800 | [diff] [blame] | 3825 | trace_parser_put(&iter->parser); |
Li Zefan | 79fe249 | 2009-09-22 13:54:28 +0800 | [diff] [blame] | 3826 | } |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3827 | } else |
| 3828 | file->private_data = iter; |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 3829 | |
| 3830 | out_unlock: |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 3831 | mutex_unlock(&ops->func_hash->regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3832 | |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 3833 | out: |
| 3834 | if (ret) { |
| 3835 | kfree(iter); |
| 3836 | if (tr) |
| 3837 | trace_array_put(tr); |
| 3838 | } |
| 3839 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 3840 | return ret; |
| 3841 | } |
| 3842 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 3843 | static int |
| 3844 | ftrace_filter_open(struct inode *inode, struct file *file) |
| 3845 | { |
Steven Rostedt (Red Hat) | e3b3e2e | 2013-11-11 23:07:14 -0500 | [diff] [blame] | 3846 | struct ftrace_ops *ops = inode->i_private; |
| 3847 | |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 3848 | /* Checks for tracefs lockdown */ |
Steven Rostedt (Red Hat) | e3b3e2e | 2013-11-11 23:07:14 -0500 | [diff] [blame] | 3849 | return ftrace_regex_open(ops, |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 3850 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_PROBES, |
Steven Rostedt | 69a3083 | 2011-12-19 15:21:16 -0500 | [diff] [blame] | 3851 | inode, file); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 3852 | } |
| 3853 | |
| 3854 | static int |
| 3855 | ftrace_notrace_open(struct inode *inode, struct file *file) |
| 3856 | { |
Steven Rostedt (Red Hat) | e3b3e2e | 2013-11-11 23:07:14 -0500 | [diff] [blame] | 3857 | struct ftrace_ops *ops = inode->i_private; |
| 3858 | |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 3859 | /* Checks for tracefs lockdown */ |
Steven Rostedt (Red Hat) | e3b3e2e | 2013-11-11 23:07:14 -0500 | [diff] [blame] | 3860 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3861 | inode, file); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 3862 | } |
| 3863 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3864 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
| 3865 | struct ftrace_glob { |
| 3866 | char *search; |
| 3867 | unsigned len; |
| 3868 | int type; |
| 3869 | }; |
| 3870 | |
Thiago Jung Bauermann | 7132e2d | 2016-04-25 18:56:14 -0300 | [diff] [blame] | 3871 | /* |
| 3872 | * If symbols in an architecture don't correspond exactly to the user-visible |
| 3873 | * name of what they represent, it is possible to define this function to |
| 3874 | * perform the necessary adjustments. |
| 3875 | */ |
| 3876 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) |
| 3877 | { |
| 3878 | return str; |
| 3879 | } |
| 3880 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3881 | static int ftrace_match(char *str, struct ftrace_glob *g) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3882 | { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3883 | int matched = 0; |
Li Zefan | 751e998 | 2010-01-14 10:53:02 +0800 | [diff] [blame] | 3884 | int slen; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3885 | |
Thiago Jung Bauermann | 7132e2d | 2016-04-25 18:56:14 -0300 | [diff] [blame] | 3886 | str = arch_ftrace_match_adjust(str, g->search); |
| 3887 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3888 | switch (g->type) { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3889 | case MATCH_FULL: |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3890 | if (strcmp(str, g->search) == 0) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3891 | matched = 1; |
| 3892 | break; |
| 3893 | case MATCH_FRONT_ONLY: |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3894 | if (strncmp(str, g->search, g->len) == 0) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3895 | matched = 1; |
| 3896 | break; |
| 3897 | case MATCH_MIDDLE_ONLY: |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3898 | if (strstr(str, g->search)) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3899 | matched = 1; |
| 3900 | break; |
| 3901 | case MATCH_END_ONLY: |
Li Zefan | 751e998 | 2010-01-14 10:53:02 +0800 | [diff] [blame] | 3902 | slen = strlen(str); |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3903 | if (slen >= g->len && |
| 3904 | memcmp(str + slen - g->len, g->search, g->len) == 0) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3905 | matched = 1; |
| 3906 | break; |
Masami Hiramatsu | 60f1d5e | 2016-10-05 20:58:15 +0900 | [diff] [blame] | 3907 | case MATCH_GLOB: |
| 3908 | if (glob_match(g->search, str)) |
| 3909 | matched = 1; |
| 3910 | break; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 3911 | } |
| 3912 | |
| 3913 | return matched; |
| 3914 | } |
| 3915 | |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 3916 | static int |
Dmitry Safonov | f0a3b15 | 2015-09-29 19:46:13 +0300 | [diff] [blame] | 3917 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
Steven Rostedt | 996e87b | 2011-04-26 16:11:03 -0400 | [diff] [blame] | 3918 | { |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 3919 | struct ftrace_func_entry *entry; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 3920 | int ret = 0; |
| 3921 | |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3922 | entry = ftrace_lookup_ip(hash, rec->ip); |
Dmitry Safonov | f0a3b15 | 2015-09-29 19:46:13 +0300 | [diff] [blame] | 3923 | if (clear_filter) { |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3924 | /* Do nothing if it doesn't exist */ |
| 3925 | if (!entry) |
| 3926 | return 0; |
| 3927 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 3928 | free_hash_entry(hash, entry); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 3929 | } else { |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3930 | /* Do nothing if it exists */ |
| 3931 | if (entry) |
| 3932 | return 0; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 3933 | |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 3934 | ret = add_hash_entry(hash, rec->ip); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 3935 | } |
| 3936 | return ret; |
Steven Rostedt | 996e87b | 2011-04-26 16:11:03 -0400 | [diff] [blame] | 3937 | } |
| 3938 | |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 3939 | static int |
Steven Rostedt (VMware) | f79b3f3 | 2019-02-11 15:00:48 -0500 | [diff] [blame] | 3940 | add_rec_by_index(struct ftrace_hash *hash, struct ftrace_glob *func_g, |
| 3941 | int clear_filter) |
| 3942 | { |
| 3943 | long index = simple_strtoul(func_g->search, NULL, 0); |
| 3944 | struct ftrace_page *pg; |
| 3945 | struct dyn_ftrace *rec; |
| 3946 | |
| 3947 | /* The index starts at 1 */ |
| 3948 | if (--index < 0) |
| 3949 | return 0; |
| 3950 | |
| 3951 | do_for_each_ftrace_rec(pg, rec) { |
| 3952 | if (pg->index <= index) { |
| 3953 | index -= pg->index; |
| 3954 | /* this is a double loop, break goes to the next page */ |
| 3955 | break; |
| 3956 | } |
| 3957 | rec = &pg->records[index]; |
| 3958 | enter_record(hash, rec, clear_filter); |
| 3959 | return 1; |
| 3960 | } while_for_each_ftrace_rec(); |
| 3961 | return 0; |
| 3962 | } |
| 3963 | |
| 3964 | static int |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 3965 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
| 3966 | struct ftrace_glob *mod_g, int exclude_mod) |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 3967 | { |
| 3968 | char str[KSYM_SYMBOL_LEN]; |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 3969 | char *modname; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 3970 | |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 3971 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); |
| 3972 | |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 3973 | if (mod_g) { |
| 3974 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; |
| 3975 | |
| 3976 | /* blank module name to match all modules */ |
| 3977 | if (!mod_g->len) { |
| 3978 | /* blank module globbing: modname xor exclude_mod */ |
Steven Rostedt (VMware) | 77c0edd | 2017-05-03 11:41:44 -0400 | [diff] [blame] | 3979 | if (!exclude_mod != !modname) |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 3980 | goto func_match; |
| 3981 | return 0; |
| 3982 | } |
| 3983 | |
Steven Rostedt (VMware) | 77c0edd | 2017-05-03 11:41:44 -0400 | [diff] [blame] | 3984 | /* |
| 3985 | * exclude_mod is set to trace everything but the given |
| 3986 | * module. If it is set and the module matches, then |
| 3987 | * return 0. If it is not set, and the module doesn't match |
| 3988 | * also return 0. Otherwise, check the function to see if |
| 3989 | * that matches. |
| 3990 | */ |
| 3991 | if (!mod_matches == !exclude_mod) |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 3992 | return 0; |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 3993 | func_match: |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 3994 | /* blank search means to match all funcs in the mod */ |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3995 | if (!func_g->len) |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 3996 | return 1; |
| 3997 | } |
| 3998 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 3999 | return ftrace_match(str, func_g); |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4000 | } |
| 4001 | |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 4002 | static int |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4003 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 4004 | { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 4005 | struct ftrace_page *pg; |
| 4006 | struct dyn_ftrace *rec; |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4007 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 4008 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
| 4009 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; |
| 4010 | int exclude_mod = 0; |
Li Zefan | 311d16d | 2009-12-08 11:15:11 +0800 | [diff] [blame] | 4011 | int found = 0; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 4012 | int ret; |
Dan Carpenter | 2e028c4 | 2017-07-12 10:35:57 +0300 | [diff] [blame] | 4013 | int clear_filter = 0; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 4014 | |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 4015 | if (func) { |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4016 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
| 4017 | &clear_filter); |
| 4018 | func_g.len = strlen(func_g.search); |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 4019 | } |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 4020 | |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 4021 | if (mod) { |
| 4022 | mod_g.type = filter_parse_regex(mod, strlen(mod), |
| 4023 | &mod_g.search, &exclude_mod); |
| 4024 | mod_g.len = strlen(mod_g.search); |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 4025 | } |
| 4026 | |
Steven Rostedt | 52baf11 | 2009-02-14 01:15:39 -0500 | [diff] [blame] | 4027 | mutex_lock(&ftrace_lock); |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 4028 | |
| 4029 | if (unlikely(ftrace_disabled)) |
| 4030 | goto out_unlock; |
| 4031 | |
Steven Rostedt (VMware) | f79b3f3 | 2019-02-11 15:00:48 -0500 | [diff] [blame] | 4032 | if (func_g.type == MATCH_INDEX) { |
| 4033 | found = add_rec_by_index(hash, &func_g, clear_filter); |
| 4034 | goto out_unlock; |
| 4035 | } |
| 4036 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 4037 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt (Red Hat) | 546fece | 2016-11-14 16:31:49 -0500 | [diff] [blame] | 4038 | |
| 4039 | if (rec->flags & FTRACE_FL_DISABLED) |
| 4040 | continue; |
| 4041 | |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 4042 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
Dmitry Safonov | f0a3b15 | 2015-09-29 19:46:13 +0300 | [diff] [blame] | 4043 | ret = enter_record(hash, rec, clear_filter); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 4044 | if (ret < 0) { |
| 4045 | found = ret; |
| 4046 | goto out_unlock; |
| 4047 | } |
Li Zefan | 311d16d | 2009-12-08 11:15:11 +0800 | [diff] [blame] | 4048 | found = 1; |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 4049 | } |
| 4050 | } while_for_each_ftrace_rec(); |
Steven Rostedt | b9df92d | 2011-04-28 20:32:08 -0400 | [diff] [blame] | 4051 | out_unlock: |
Steven Rostedt | 52baf11 | 2009-02-14 01:15:39 -0500 | [diff] [blame] | 4052 | mutex_unlock(&ftrace_lock); |
Li Zefan | 311d16d | 2009-12-08 11:15:11 +0800 | [diff] [blame] | 4053 | |
| 4054 | return found; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4055 | } |
| 4056 | |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4057 | static int |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 4058 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4059 | { |
Dmitry Safonov | f0a3b15 | 2015-09-29 19:46:13 +0300 | [diff] [blame] | 4060 | return match_records(hash, buff, len, NULL); |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4061 | } |
| 4062 | |
Steven Rostedt (VMware) | e16b35d | 2017-04-04 14:46:56 -0400 | [diff] [blame] | 4063 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
| 4064 | struct ftrace_ops_hash *old_hash) |
| 4065 | { |
| 4066 | struct ftrace_ops *op; |
| 4067 | |
| 4068 | if (!ftrace_enabled) |
| 4069 | return; |
| 4070 | |
| 4071 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { |
| 4072 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); |
| 4073 | return; |
| 4074 | } |
| 4075 | |
| 4076 | /* |
| 4077 | * If this is the shared global_ops filter, then we need to |
| 4078 | * check if there is another ops that shares it, is enabled. |
| 4079 | * If so, we still need to run the modify code. |
| 4080 | */ |
| 4081 | if (ops->func_hash != &global_ops.local_hash) |
| 4082 | return; |
| 4083 | |
| 4084 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 4085 | if (op->func_hash == &global_ops.local_hash && |
| 4086 | op->flags & FTRACE_OPS_FL_ENABLED) { |
| 4087 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); |
| 4088 | /* Only need to do this once */ |
| 4089 | return; |
| 4090 | } |
| 4091 | } while_for_each_ftrace_op(op); |
| 4092 | } |
| 4093 | |
| 4094 | static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops, |
| 4095 | struct ftrace_hash **orig_hash, |
| 4096 | struct ftrace_hash *hash, |
| 4097 | int enable) |
| 4098 | { |
| 4099 | struct ftrace_ops_hash old_hash_ops; |
| 4100 | struct ftrace_hash *old_hash; |
| 4101 | int ret; |
| 4102 | |
| 4103 | old_hash = *orig_hash; |
| 4104 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; |
| 4105 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; |
| 4106 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
| 4107 | if (!ret) { |
| 4108 | ftrace_ops_update_code(ops, &old_hash_ops); |
| 4109 | free_ftrace_hash_rcu(old_hash); |
| 4110 | } |
| 4111 | return ret; |
| 4112 | } |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4113 | |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4114 | static bool module_exists(const char *module) |
| 4115 | { |
| 4116 | /* All modules have the symbol __this_module */ |
Rasmus Villemoes | 0f5e5a3 | 2019-03-20 09:17:57 +0100 | [diff] [blame] | 4117 | static const char this_mod[] = "__this_module"; |
Salvatore Mesoraca | 419e9fe | 2018-03-30 10:53:08 +0200 | [diff] [blame] | 4118 | char modname[MAX_PARAM_PREFIX_LEN + sizeof(this_mod) + 2]; |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4119 | unsigned long val; |
| 4120 | int n; |
| 4121 | |
Salvatore Mesoraca | 419e9fe | 2018-03-30 10:53:08 +0200 | [diff] [blame] | 4122 | n = snprintf(modname, sizeof(modname), "%s:%s", module, this_mod); |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4123 | |
Salvatore Mesoraca | 419e9fe | 2018-03-30 10:53:08 +0200 | [diff] [blame] | 4124 | if (n > sizeof(modname) - 1) |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4125 | return false; |
| 4126 | |
| 4127 | val = module_kallsyms_lookup_name(modname); |
| 4128 | return val != 0; |
| 4129 | } |
| 4130 | |
| 4131 | static int cache_mod(struct trace_array *tr, |
| 4132 | const char *func, char *module, int enable) |
| 4133 | { |
| 4134 | struct ftrace_mod_load *ftrace_mod, *n; |
| 4135 | struct list_head *head = enable ? &tr->mod_trace : &tr->mod_notrace; |
| 4136 | int ret; |
| 4137 | |
| 4138 | mutex_lock(&ftrace_lock); |
| 4139 | |
| 4140 | /* We do not cache inverse filters */ |
| 4141 | if (func[0] == '!') { |
| 4142 | func++; |
| 4143 | ret = -EINVAL; |
| 4144 | |
| 4145 | /* Look to remove this hash */ |
| 4146 | list_for_each_entry_safe(ftrace_mod, n, head, list) { |
| 4147 | if (strcmp(ftrace_mod->module, module) != 0) |
| 4148 | continue; |
| 4149 | |
| 4150 | /* no func matches all */ |
Dan Carpenter | 44925df | 2017-07-12 10:33:40 +0300 | [diff] [blame] | 4151 | if (strcmp(func, "*") == 0 || |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4152 | (ftrace_mod->func && |
| 4153 | strcmp(ftrace_mod->func, func) == 0)) { |
| 4154 | ret = 0; |
| 4155 | free_ftrace_mod(ftrace_mod); |
| 4156 | continue; |
| 4157 | } |
| 4158 | } |
| 4159 | goto out; |
| 4160 | } |
| 4161 | |
| 4162 | ret = -EINVAL; |
| 4163 | /* We only care about modules that have not been loaded yet */ |
| 4164 | if (module_exists(module)) |
| 4165 | goto out; |
| 4166 | |
| 4167 | /* Save this string off, and execute it when the module is loaded */ |
| 4168 | ret = ftrace_add_mod(tr, func, module, enable); |
| 4169 | out: |
| 4170 | mutex_unlock(&ftrace_lock); |
| 4171 | |
| 4172 | return ret; |
| 4173 | } |
| 4174 | |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4175 | static int |
| 4176 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, |
| 4177 | int reset, int enable); |
| 4178 | |
Arnd Bergmann | 69449bbd | 2017-07-10 10:44:03 +0200 | [diff] [blame] | 4179 | #ifdef CONFIG_MODULES |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4180 | static void process_mod_list(struct list_head *head, struct ftrace_ops *ops, |
| 4181 | char *mod, bool enable) |
| 4182 | { |
| 4183 | struct ftrace_mod_load *ftrace_mod, *n; |
| 4184 | struct ftrace_hash **orig_hash, *new_hash; |
| 4185 | LIST_HEAD(process_mods); |
| 4186 | char *func; |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4187 | |
| 4188 | mutex_lock(&ops->func_hash->regex_lock); |
| 4189 | |
| 4190 | if (enable) |
| 4191 | orig_hash = &ops->func_hash->filter_hash; |
| 4192 | else |
| 4193 | orig_hash = &ops->func_hash->notrace_hash; |
| 4194 | |
| 4195 | new_hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, |
| 4196 | *orig_hash); |
| 4197 | if (!new_hash) |
Steven Rostedt (VMware) | 3b58a3c | 2017-06-28 09:09:38 -0400 | [diff] [blame] | 4198 | goto out; /* warn? */ |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4199 | |
| 4200 | mutex_lock(&ftrace_lock); |
| 4201 | |
| 4202 | list_for_each_entry_safe(ftrace_mod, n, head, list) { |
| 4203 | |
| 4204 | if (strcmp(ftrace_mod->module, mod) != 0) |
| 4205 | continue; |
| 4206 | |
| 4207 | if (ftrace_mod->func) |
| 4208 | func = kstrdup(ftrace_mod->func, GFP_KERNEL); |
| 4209 | else |
| 4210 | func = kstrdup("*", GFP_KERNEL); |
| 4211 | |
| 4212 | if (!func) /* warn? */ |
| 4213 | continue; |
| 4214 | |
Baokun Li | 3ecda64 | 2021-06-08 11:11:08 +0800 | [diff] [blame] | 4215 | list_move(&ftrace_mod->list, &process_mods); |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4216 | |
| 4217 | /* Use the newly allocated func, as it may be "*" */ |
| 4218 | kfree(ftrace_mod->func); |
| 4219 | ftrace_mod->func = func; |
| 4220 | } |
| 4221 | |
| 4222 | mutex_unlock(&ftrace_lock); |
| 4223 | |
| 4224 | list_for_each_entry_safe(ftrace_mod, n, &process_mods, list) { |
| 4225 | |
| 4226 | func = ftrace_mod->func; |
| 4227 | |
| 4228 | /* Grabs ftrace_lock, which is why we have this extra step */ |
| 4229 | match_records(new_hash, func, strlen(func), mod); |
| 4230 | free_ftrace_mod(ftrace_mod); |
| 4231 | } |
| 4232 | |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 4233 | if (enable && list_empty(head)) |
| 4234 | new_hash->flags &= ~FTRACE_HASH_FL_MOD; |
| 4235 | |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4236 | mutex_lock(&ftrace_lock); |
| 4237 | |
Alex Shi | 045e269 | 2020-11-06 22:54:46 +0800 | [diff] [blame] | 4238 | ftrace_hash_move_and_update_ops(ops, orig_hash, |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4239 | new_hash, enable); |
| 4240 | mutex_unlock(&ftrace_lock); |
| 4241 | |
Steven Rostedt (VMware) | 3b58a3c | 2017-06-28 09:09:38 -0400 | [diff] [blame] | 4242 | out: |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4243 | mutex_unlock(&ops->func_hash->regex_lock); |
| 4244 | |
| 4245 | free_ftrace_hash(new_hash); |
| 4246 | } |
| 4247 | |
| 4248 | static void process_cached_mods(const char *mod_name) |
| 4249 | { |
| 4250 | struct trace_array *tr; |
| 4251 | char *mod; |
| 4252 | |
| 4253 | mod = kstrdup(mod_name, GFP_KERNEL); |
| 4254 | if (!mod) |
| 4255 | return; |
| 4256 | |
| 4257 | mutex_lock(&trace_types_lock); |
| 4258 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
| 4259 | if (!list_empty(&tr->mod_trace)) |
| 4260 | process_mod_list(&tr->mod_trace, tr->ops, mod, true); |
| 4261 | if (!list_empty(&tr->mod_notrace)) |
| 4262 | process_mod_list(&tr->mod_notrace, tr->ops, mod, false); |
| 4263 | } |
| 4264 | mutex_unlock(&trace_types_lock); |
| 4265 | |
| 4266 | kfree(mod); |
| 4267 | } |
Arnd Bergmann | 69449bbd | 2017-07-10 10:44:03 +0200 | [diff] [blame] | 4268 | #endif |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 4269 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4270 | /* |
| 4271 | * We register the module command as a template to show others how |
| 4272 | * to register the a command as well. |
| 4273 | */ |
| 4274 | |
| 4275 | static int |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4276 | ftrace_mod_callback(struct trace_array *tr, struct ftrace_hash *hash, |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4277 | char *func_orig, char *cmd, char *module, int enable) |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4278 | { |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4279 | char *func; |
Dmitry Safonov | 5e3949f | 2015-09-29 19:46:12 +0300 | [diff] [blame] | 4280 | int ret; |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4281 | |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4282 | /* match_records() modifies func, and we need the original */ |
| 4283 | func = kstrdup(func_orig, GFP_KERNEL); |
| 4284 | if (!func) |
| 4285 | return -ENOMEM; |
| 4286 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4287 | /* |
| 4288 | * cmd == 'mod' because we only registered this func |
| 4289 | * for the 'mod' ftrace_func_command. |
| 4290 | * But if you register one func with multiple commands, |
| 4291 | * you can tell which command was used by the cmd |
| 4292 | * parameter. |
| 4293 | */ |
Dmitry Safonov | f0a3b15 | 2015-09-29 19:46:13 +0300 | [diff] [blame] | 4294 | ret = match_records(hash, func, strlen(func), module); |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4295 | kfree(func); |
| 4296 | |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 4297 | if (!ret) |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 4298 | return cache_mod(tr, func_orig, module, enable); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 4299 | if (ret < 0) |
| 4300 | return ret; |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 4301 | return 0; |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4302 | } |
| 4303 | |
| 4304 | static struct ftrace_func_command ftrace_mod_cmd = { |
| 4305 | .name = "mod", |
| 4306 | .func = ftrace_mod_callback, |
| 4307 | }; |
| 4308 | |
| 4309 | static int __init ftrace_mod_cmd_init(void) |
| 4310 | { |
| 4311 | return register_ftrace_command(&ftrace_mod_cmd); |
| 4312 | } |
Steven Rostedt | 6f41567 | 2012-10-05 12:13:07 -0400 | [diff] [blame] | 4313 | core_initcall(ftrace_mod_cmd_init); |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4314 | |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 4315 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 4316 | struct ftrace_ops *op, struct ftrace_regs *fregs) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4317 | { |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4318 | struct ftrace_probe_ops *probe_ops; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4319 | struct ftrace_func_probe *probe; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4320 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4321 | probe = container_of(op, struct ftrace_func_probe, ops); |
| 4322 | probe_ops = probe->probe_ops; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4323 | |
| 4324 | /* |
| 4325 | * Disable preemption for these calls to prevent a RCU grace |
| 4326 | * period. This syncs the hash iteration and freeing of items |
| 4327 | * on the hash. rcu_read_lock is too dangerous here. |
| 4328 | */ |
Steven Rostedt | 5168ae5 | 2010-06-03 09:36:50 -0400 | [diff] [blame] | 4329 | preempt_disable_notrace(); |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 4330 | probe_ops->func(ip, parent_ip, probe->tr, probe_ops, probe->data); |
Steven Rostedt | 5168ae5 | 2010-06-03 09:36:50 -0400 | [diff] [blame] | 4331 | preempt_enable_notrace(); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4332 | } |
| 4333 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4334 | struct ftrace_func_map { |
| 4335 | struct ftrace_func_entry entry; |
| 4336 | void *data; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4337 | }; |
| 4338 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4339 | struct ftrace_func_mapper { |
| 4340 | struct ftrace_hash hash; |
| 4341 | }; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4342 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4343 | /** |
| 4344 | * allocate_ftrace_func_mapper - allocate a new ftrace_func_mapper |
| 4345 | * |
| 4346 | * Returns a ftrace_func_mapper descriptor that can be used to map ips to data. |
| 4347 | */ |
| 4348 | struct ftrace_func_mapper *allocate_ftrace_func_mapper(void) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4349 | { |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4350 | struct ftrace_hash *hash; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4351 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4352 | /* |
| 4353 | * The mapper is simply a ftrace_hash, but since the entries |
| 4354 | * in the hash are not ftrace_func_entry type, we define it |
| 4355 | * as a separate structure. |
| 4356 | */ |
| 4357 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
| 4358 | return (struct ftrace_func_mapper *)hash; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4359 | } |
| 4360 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4361 | /** |
| 4362 | * ftrace_func_mapper_find_ip - Find some data mapped to an ip |
| 4363 | * @mapper: The mapper that has the ip maps |
| 4364 | * @ip: the instruction pointer to find the data for |
| 4365 | * |
| 4366 | * Returns the data mapped to @ip if found otherwise NULL. The return |
| 4367 | * is actually the address of the mapper data pointer. The address is |
| 4368 | * returned for use cases where the data is no bigger than a long, and |
| 4369 | * the user can use the data pointer as its data instead of having to |
| 4370 | * allocate more memory for the reference. |
| 4371 | */ |
| 4372 | void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, |
| 4373 | unsigned long ip) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4374 | { |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4375 | struct ftrace_func_entry *entry; |
| 4376 | struct ftrace_func_map *map; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4377 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4378 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
| 4379 | if (!entry) |
| 4380 | return NULL; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4381 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4382 | map = (struct ftrace_func_map *)entry; |
| 4383 | return &map->data; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4384 | } |
| 4385 | |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4386 | /** |
| 4387 | * ftrace_func_mapper_add_ip - Map some data to an ip |
| 4388 | * @mapper: The mapper that has the ip maps |
| 4389 | * @ip: The instruction pointer address to map @data to |
| 4390 | * @data: The data to map to @ip |
| 4391 | * |
Qiujun Huang | fdda88d | 2020-10-02 22:31:26 +0800 | [diff] [blame] | 4392 | * Returns 0 on success otherwise an error. |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4393 | */ |
| 4394 | int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, |
| 4395 | unsigned long ip, void *data) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4396 | { |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4397 | struct ftrace_func_entry *entry; |
| 4398 | struct ftrace_func_map *map; |
| 4399 | |
| 4400 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
| 4401 | if (entry) |
| 4402 | return -EBUSY; |
| 4403 | |
| 4404 | map = kmalloc(sizeof(*map), GFP_KERNEL); |
| 4405 | if (!map) |
| 4406 | return -ENOMEM; |
| 4407 | |
| 4408 | map->entry.ip = ip; |
| 4409 | map->data = data; |
| 4410 | |
| 4411 | __add_hash_entry(&mapper->hash, &map->entry); |
| 4412 | |
| 4413 | return 0; |
| 4414 | } |
| 4415 | |
| 4416 | /** |
| 4417 | * ftrace_func_mapper_remove_ip - Remove an ip from the mapping |
| 4418 | * @mapper: The mapper that has the ip maps |
| 4419 | * @ip: The instruction pointer address to remove the data from |
| 4420 | * |
| 4421 | * Returns the data if it is found, otherwise NULL. |
| 4422 | * Note, if the data pointer is used as the data itself, (see |
| 4423 | * ftrace_func_mapper_find_ip(), then the return value may be meaningless, |
| 4424 | * if the data pointer was set to zero. |
| 4425 | */ |
| 4426 | void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, |
| 4427 | unsigned long ip) |
| 4428 | { |
| 4429 | struct ftrace_func_entry *entry; |
| 4430 | struct ftrace_func_map *map; |
| 4431 | void *data; |
| 4432 | |
| 4433 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
| 4434 | if (!entry) |
| 4435 | return NULL; |
| 4436 | |
| 4437 | map = (struct ftrace_func_map *)entry; |
| 4438 | data = map->data; |
| 4439 | |
| 4440 | remove_hash_entry(&mapper->hash, entry); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4441 | kfree(entry); |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4442 | |
| 4443 | return data; |
| 4444 | } |
| 4445 | |
| 4446 | /** |
| 4447 | * free_ftrace_func_mapper - free a mapping of ips and data |
| 4448 | * @mapper: The mapper that has the ip maps |
| 4449 | * @free_func: A function to be called on each data item. |
| 4450 | * |
| 4451 | * This is used to free the function mapper. The @free_func is optional |
| 4452 | * and can be used if the data needs to be freed as well. |
| 4453 | */ |
| 4454 | void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, |
| 4455 | ftrace_mapper_func free_func) |
| 4456 | { |
| 4457 | struct ftrace_func_entry *entry; |
| 4458 | struct ftrace_func_map *map; |
| 4459 | struct hlist_head *hhd; |
Wei Li | 04e03d9 | 2019-06-06 11:17:54 +0800 | [diff] [blame] | 4460 | int size, i; |
| 4461 | |
| 4462 | if (!mapper) |
| 4463 | return; |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4464 | |
| 4465 | if (free_func && mapper->hash.count) { |
Wei Li | 04e03d9 | 2019-06-06 11:17:54 +0800 | [diff] [blame] | 4466 | size = 1 << mapper->hash.size_bits; |
Steven Rostedt (VMware) | 41794f1 | 2017-04-03 20:58:35 -0400 | [diff] [blame] | 4467 | for (i = 0; i < size; i++) { |
| 4468 | hhd = &mapper->hash.buckets[i]; |
| 4469 | hlist_for_each_entry(entry, hhd, hlist) { |
| 4470 | map = (struct ftrace_func_map *)entry; |
| 4471 | free_func(map); |
| 4472 | } |
| 4473 | } |
| 4474 | } |
| 4475 | free_ftrace_hash(&mapper->hash); |
| 4476 | } |
| 4477 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4478 | static void release_probe(struct ftrace_func_probe *probe) |
| 4479 | { |
| 4480 | struct ftrace_probe_ops *probe_ops; |
| 4481 | |
| 4482 | mutex_lock(&ftrace_lock); |
| 4483 | |
| 4484 | WARN_ON(probe->ref <= 0); |
| 4485 | |
| 4486 | /* Subtract the ref that was used to protect this instance */ |
| 4487 | probe->ref--; |
| 4488 | |
| 4489 | if (!probe->ref) { |
| 4490 | probe_ops = probe->probe_ops; |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 4491 | /* |
| 4492 | * Sending zero as ip tells probe_ops to free |
| 4493 | * the probe->data itself |
| 4494 | */ |
| 4495 | if (probe_ops->free) |
| 4496 | probe_ops->free(probe_ops, probe->tr, 0, probe->data); |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4497 | list_del(&probe->list); |
| 4498 | kfree(probe); |
| 4499 | } |
| 4500 | mutex_unlock(&ftrace_lock); |
| 4501 | } |
| 4502 | |
| 4503 | static void acquire_probe_locked(struct ftrace_func_probe *probe) |
| 4504 | { |
| 4505 | /* |
| 4506 | * Add one ref to keep it from being freed when releasing the |
| 4507 | * ftrace_lock mutex. |
| 4508 | */ |
| 4509 | probe->ref++; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4510 | } |
| 4511 | |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4512 | int |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4513 | register_ftrace_function_probe(char *glob, struct trace_array *tr, |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4514 | struct ftrace_probe_ops *probe_ops, |
| 4515 | void *data) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4516 | { |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4517 | struct ftrace_func_entry *entry; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4518 | struct ftrace_func_probe *probe; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4519 | struct ftrace_hash **orig_hash; |
| 4520 | struct ftrace_hash *old_hash; |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4521 | struct ftrace_hash *hash; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4522 | int count = 0; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4523 | int size; |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4524 | int ret; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4525 | int i; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4526 | |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4527 | if (WARN_ON(!tr)) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4528 | return -EINVAL; |
| 4529 | |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4530 | /* We do not support '!' for function probes */ |
| 4531 | if (WARN_ON(glob[0] == '!')) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4532 | return -EINVAL; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4533 | |
Steven Rostedt (Red Hat) | 7485058e | 2015-01-13 14:03:38 -0500 | [diff] [blame] | 4534 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4535 | mutex_lock(&ftrace_lock); |
| 4536 | /* Check if the probe_ops is already registered */ |
| 4537 | list_for_each_entry(probe, &tr->func_probes, list) { |
| 4538 | if (probe->probe_ops == probe_ops) |
| 4539 | break; |
| 4540 | } |
| 4541 | if (&probe->list == &tr->func_probes) { |
| 4542 | probe = kzalloc(sizeof(*probe), GFP_KERNEL); |
| 4543 | if (!probe) { |
| 4544 | mutex_unlock(&ftrace_lock); |
| 4545 | return -ENOMEM; |
| 4546 | } |
| 4547 | probe->probe_ops = probe_ops; |
| 4548 | probe->ops.func = function_trace_probe_call; |
| 4549 | probe->tr = tr; |
| 4550 | ftrace_ops_init(&probe->ops); |
| 4551 | list_add(&probe->list, &tr->func_probes); |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4552 | } |
| 4553 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4554 | acquire_probe_locked(probe); |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4555 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4556 | mutex_unlock(&ftrace_lock); |
| 4557 | |
Steven Rostedt (VMware) | 372e0d0 | 2019-08-30 16:30:01 -0400 | [diff] [blame] | 4558 | /* |
| 4559 | * Note, there's a small window here that the func_hash->filter_hash |
Qiujun Huang | fdda88d | 2020-10-02 22:31:26 +0800 | [diff] [blame] | 4560 | * may be NULL or empty. Need to be careful when reading the loop. |
Steven Rostedt (VMware) | 372e0d0 | 2019-08-30 16:30:01 -0400 | [diff] [blame] | 4561 | */ |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4562 | mutex_lock(&probe->ops.func_hash->regex_lock); |
| 4563 | |
| 4564 | orig_hash = &probe->ops.func_hash->filter_hash; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4565 | old_hash = *orig_hash; |
| 4566 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
| 4567 | |
Naveen N. Rao | 5b0022d | 2019-07-04 20:04:42 +0530 | [diff] [blame] | 4568 | if (!hash) { |
| 4569 | ret = -ENOMEM; |
| 4570 | goto out; |
| 4571 | } |
| 4572 | |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4573 | ret = ftrace_match_records(hash, glob, strlen(glob)); |
| 4574 | |
| 4575 | /* Nothing found? */ |
| 4576 | if (!ret) |
| 4577 | ret = -EINVAL; |
| 4578 | |
| 4579 | if (ret < 0) |
Steven Rostedt (Red Hat) | 5ae0bf5 | 2013-05-09 18:20:37 -0400 | [diff] [blame] | 4580 | goto out; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4581 | |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4582 | size = 1 << hash->size_bits; |
| 4583 | for (i = 0; i < size; i++) { |
| 4584 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
| 4585 | if (ftrace_lookup_ip(old_hash, entry->ip)) |
| 4586 | continue; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4587 | /* |
| 4588 | * The caller might want to do something special |
| 4589 | * for each function we find. We call the callback |
| 4590 | * to give the caller an opportunity to do so. |
| 4591 | */ |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4592 | if (probe_ops->init) { |
| 4593 | ret = probe_ops->init(probe_ops, tr, |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 4594 | entry->ip, data, |
| 4595 | &probe->data); |
| 4596 | if (ret < 0) { |
| 4597 | if (probe_ops->free && count) |
| 4598 | probe_ops->free(probe_ops, tr, |
| 4599 | 0, probe->data); |
| 4600 | probe->data = NULL; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4601 | goto out; |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 4602 | } |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4603 | } |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4604 | count++; |
| 4605 | } |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4606 | } |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 4607 | |
Steven Rostedt (Red Hat) | 5ae0bf5 | 2013-05-09 18:20:37 -0400 | [diff] [blame] | 4608 | mutex_lock(&ftrace_lock); |
| 4609 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4610 | if (!count) { |
| 4611 | /* Nothing was added? */ |
| 4612 | ret = -EINVAL; |
| 4613 | goto out_unlock; |
| 4614 | } |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4615 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4616 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, |
| 4617 | hash, 1); |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4618 | if (ret < 0) |
Steven Rostedt (VMware) | 8d70725 | 2017-04-05 13:36:18 -0400 | [diff] [blame] | 4619 | goto err_unlock; |
Steven Rostedt (Red Hat) | 546fece | 2016-11-14 16:31:49 -0500 | [diff] [blame] | 4620 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4621 | /* One ref for each new function traced */ |
| 4622 | probe->ref += count; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4623 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4624 | if (!(probe->ops.flags & FTRACE_OPS_FL_ENABLED)) |
| 4625 | ret = ftrace_startup(&probe->ops, 0); |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4626 | |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4627 | out_unlock: |
Steven Rostedt (Red Hat) | 5ae0bf5 | 2013-05-09 18:20:37 -0400 | [diff] [blame] | 4628 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4629 | |
| 4630 | if (!ret) |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4631 | ret = count; |
Steven Rostedt (Red Hat) | 5ae0bf5 | 2013-05-09 18:20:37 -0400 | [diff] [blame] | 4632 | out: |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4633 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4634 | free_ftrace_hash(hash); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4635 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4636 | release_probe(probe); |
| 4637 | |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4638 | return ret; |
Steven Rostedt (VMware) | 8d70725 | 2017-04-05 13:36:18 -0400 | [diff] [blame] | 4639 | |
| 4640 | err_unlock: |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4641 | if (!probe_ops->free || !count) |
Steven Rostedt (VMware) | 8d70725 | 2017-04-05 13:36:18 -0400 | [diff] [blame] | 4642 | goto out_unlock; |
| 4643 | |
| 4644 | /* Failed to do the move, need to call the free functions */ |
| 4645 | for (i = 0; i < size; i++) { |
| 4646 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
| 4647 | if (ftrace_lookup_ip(old_hash, entry->ip)) |
| 4648 | continue; |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 4649 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
Steven Rostedt (VMware) | 8d70725 | 2017-04-05 13:36:18 -0400 | [diff] [blame] | 4650 | } |
| 4651 | } |
| 4652 | goto out_unlock; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4653 | } |
| 4654 | |
Steven Rostedt (VMware) | d3d532d | 2017-04-04 16:44:43 -0400 | [diff] [blame] | 4655 | int |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4656 | unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, |
| 4657 | struct ftrace_probe_ops *probe_ops) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4658 | { |
Steven Rostedt (VMware) | 82cc4fc | 2017-04-14 17:45:45 -0400 | [diff] [blame] | 4659 | struct ftrace_ops_hash old_hash_ops; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4660 | struct ftrace_func_entry *entry; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4661 | struct ftrace_func_probe *probe; |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4662 | struct ftrace_glob func_g; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4663 | struct ftrace_hash **orig_hash; |
| 4664 | struct ftrace_hash *old_hash; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4665 | struct ftrace_hash *hash = NULL; |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 4666 | struct hlist_node *tmp; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4667 | struct hlist_head hhd; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4668 | char str[KSYM_SYMBOL_LEN]; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4669 | int count = 0; |
| 4670 | int i, ret = -ENODEV; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4671 | int size; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4672 | |
Naveen N. Rao | cbab567 | 2017-05-16 23:21:25 +0530 | [diff] [blame] | 4673 | if (!glob || !strlen(glob) || !strcmp(glob, "*")) |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4674 | func_g.search = NULL; |
Naveen N. Rao | cbab567 | 2017-05-16 23:21:25 +0530 | [diff] [blame] | 4675 | else { |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4676 | int not; |
| 4677 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4678 | func_g.type = filter_parse_regex(glob, strlen(glob), |
| 4679 | &func_g.search, ¬); |
| 4680 | func_g.len = strlen(func_g.search); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4681 | |
Steven Rostedt | b6887d7 | 2009-02-17 12:32:04 -0500 | [diff] [blame] | 4682 | /* we do not support '!' for function probes */ |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4683 | if (WARN_ON(not)) |
Steven Rostedt (VMware) | d3d532d | 2017-04-04 16:44:43 -0400 | [diff] [blame] | 4684 | return -EINVAL; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4685 | } |
| 4686 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4687 | mutex_lock(&ftrace_lock); |
| 4688 | /* Check if the probe_ops is already registered */ |
| 4689 | list_for_each_entry(probe, &tr->func_probes, list) { |
| 4690 | if (probe->probe_ops == probe_ops) |
| 4691 | break; |
| 4692 | } |
| 4693 | if (&probe->list == &tr->func_probes) |
| 4694 | goto err_unlock_ftrace; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4695 | |
| 4696 | ret = -EINVAL; |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4697 | if (!(probe->ops.flags & FTRACE_OPS_FL_INITIALIZED)) |
| 4698 | goto err_unlock_ftrace; |
| 4699 | |
| 4700 | acquire_probe_locked(probe); |
| 4701 | |
| 4702 | mutex_unlock(&ftrace_lock); |
| 4703 | |
| 4704 | mutex_lock(&probe->ops.func_hash->regex_lock); |
| 4705 | |
| 4706 | orig_hash = &probe->ops.func_hash->filter_hash; |
| 4707 | old_hash = *orig_hash; |
| 4708 | |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4709 | if (ftrace_hash_empty(old_hash)) |
| 4710 | goto out_unlock; |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4711 | |
Steven Rostedt (VMware) | 82cc4fc | 2017-04-14 17:45:45 -0400 | [diff] [blame] | 4712 | old_hash_ops.filter_hash = old_hash; |
| 4713 | /* Probes only have filters */ |
| 4714 | old_hash_ops.notrace_hash = NULL; |
| 4715 | |
Steven Rostedt (VMware) | d3d532d | 2017-04-04 16:44:43 -0400 | [diff] [blame] | 4716 | ret = -ENOMEM; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4717 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4718 | if (!hash) |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4719 | goto out_unlock; |
| 4720 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4721 | INIT_HLIST_HEAD(&hhd); |
Steven Rostedt (Red Hat) | 7818b38 | 2013-03-13 12:42:58 -0400 | [diff] [blame] | 4722 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4723 | size = 1 << hash->size_bits; |
| 4724 | for (i = 0; i < size; i++) { |
| 4725 | hlist_for_each_entry_safe(entry, tmp, &hash->buckets[i], hlist) { |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4726 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4727 | if (func_g.search) { |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4728 | kallsyms_lookup(entry->ip, NULL, NULL, |
| 4729 | NULL, str); |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4730 | if (!ftrace_match(str, &func_g)) |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4731 | continue; |
| 4732 | } |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4733 | count++; |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4734 | remove_hash_entry(hash, entry); |
| 4735 | hlist_add_head(&entry->hlist, &hhd); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4736 | } |
| 4737 | } |
Steven Rostedt (VMware) | d3d532d | 2017-04-04 16:44:43 -0400 | [diff] [blame] | 4738 | |
| 4739 | /* Nothing found? */ |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4740 | if (!count) { |
Steven Rostedt (VMware) | d3d532d | 2017-04-04 16:44:43 -0400 | [diff] [blame] | 4741 | ret = -EINVAL; |
| 4742 | goto out_unlock; |
| 4743 | } |
| 4744 | |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4745 | mutex_lock(&ftrace_lock); |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4746 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4747 | WARN_ON(probe->ref < count); |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4748 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4749 | probe->ref -= count; |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4750 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4751 | if (ftrace_hash_empty(hash)) |
| 4752 | ftrace_shutdown(&probe->ops, 0); |
| 4753 | |
| 4754 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4755 | hash, 1); |
Steven Rostedt (VMware) | 82cc4fc | 2017-04-14 17:45:45 -0400 | [diff] [blame] | 4756 | |
| 4757 | /* still need to update the function call sites */ |
Steven Rostedt (VMware) | 1ec3a81 | 2017-04-04 18:16:29 -0400 | [diff] [blame] | 4758 | if (ftrace_enabled && !ftrace_hash_empty(hash)) |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4759 | ftrace_run_modify_code(&probe->ops, FTRACE_UPDATE_CALLS, |
Steven Rostedt (VMware) | 82cc4fc | 2017-04-14 17:45:45 -0400 | [diff] [blame] | 4760 | &old_hash_ops); |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 4761 | synchronize_rcu(); |
Steven Rostedt (Red Hat) | 3296fc4e | 2014-07-24 15:33:41 -0400 | [diff] [blame] | 4762 | |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4763 | hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) { |
| 4764 | hlist_del(&entry->hlist); |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4765 | if (probe_ops->free) |
Steven Rostedt (VMware) | 6e44431 | 2017-04-19 22:39:44 -0400 | [diff] [blame] | 4766 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
Steven Rostedt (VMware) | eee8ded | 2017-04-04 21:31:28 -0400 | [diff] [blame] | 4767 | kfree(entry); |
Steven Rostedt (Red Hat) | 7818b38 | 2013-03-13 12:42:58 -0400 | [diff] [blame] | 4768 | } |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4769 | mutex_unlock(&ftrace_lock); |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 4770 | |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4771 | out_unlock: |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4772 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
Steven Rostedt (Red Hat) | e1df4cb | 2013-03-12 10:09:42 -0400 | [diff] [blame] | 4773 | free_ftrace_hash(hash); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4774 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4775 | release_probe(probe); |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4776 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4777 | return ret; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4778 | |
Steven Rostedt (VMware) | 7b60f3d | 2017-04-18 14:50:39 -0400 | [diff] [blame] | 4779 | err_unlock_ftrace: |
| 4780 | mutex_unlock(&ftrace_lock); |
Steven Rostedt (VMware) | d3d532d | 2017-04-04 16:44:43 -0400 | [diff] [blame] | 4781 | return ret; |
Steven Rostedt | 59df055f | 2009-02-14 15:29:06 -0500 | [diff] [blame] | 4782 | } |
| 4783 | |
Naveen N. Rao | a0e6369 | 2017-05-16 23:21:26 +0530 | [diff] [blame] | 4784 | void clear_ftrace_function_probes(struct trace_array *tr) |
| 4785 | { |
| 4786 | struct ftrace_func_probe *probe, *n; |
| 4787 | |
| 4788 | list_for_each_entry_safe(probe, n, &tr->func_probes, list) |
| 4789 | unregister_ftrace_function_probe_func(NULL, tr, probe->probe_ops); |
| 4790 | } |
| 4791 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4792 | static LIST_HEAD(ftrace_commands); |
| 4793 | static DEFINE_MUTEX(ftrace_cmd_mutex); |
| 4794 | |
Tom Zanussi | 38de93a | 2013-10-24 08:34:18 -0500 | [diff] [blame] | 4795 | /* |
| 4796 | * Currently we only register ftrace commands from __init, so mark this |
| 4797 | * __init too. |
| 4798 | */ |
| 4799 | __init int register_ftrace_command(struct ftrace_func_command *cmd) |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4800 | { |
| 4801 | struct ftrace_func_command *p; |
| 4802 | int ret = 0; |
| 4803 | |
| 4804 | mutex_lock(&ftrace_cmd_mutex); |
| 4805 | list_for_each_entry(p, &ftrace_commands, list) { |
| 4806 | if (strcmp(cmd->name, p->name) == 0) { |
| 4807 | ret = -EBUSY; |
| 4808 | goto out_unlock; |
| 4809 | } |
| 4810 | } |
| 4811 | list_add(&cmd->list, &ftrace_commands); |
| 4812 | out_unlock: |
| 4813 | mutex_unlock(&ftrace_cmd_mutex); |
| 4814 | |
| 4815 | return ret; |
| 4816 | } |
| 4817 | |
Tom Zanussi | 38de93a | 2013-10-24 08:34:18 -0500 | [diff] [blame] | 4818 | /* |
| 4819 | * Currently we only unregister ftrace commands from __init, so mark |
| 4820 | * this __init too. |
| 4821 | */ |
| 4822 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4823 | { |
| 4824 | struct ftrace_func_command *p, *n; |
| 4825 | int ret = -ENODEV; |
| 4826 | |
| 4827 | mutex_lock(&ftrace_cmd_mutex); |
| 4828 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { |
| 4829 | if (strcmp(cmd->name, p->name) == 0) { |
| 4830 | ret = 0; |
| 4831 | list_del_init(&p->list); |
| 4832 | goto out_unlock; |
| 4833 | } |
| 4834 | } |
| 4835 | out_unlock: |
| 4836 | mutex_unlock(&ftrace_cmd_mutex); |
| 4837 | |
| 4838 | return ret; |
| 4839 | } |
| 4840 | |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4841 | static int ftrace_process_regex(struct ftrace_iterator *iter, |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4842 | char *buff, int len, int enable) |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4843 | { |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4844 | struct ftrace_hash *hash = iter->hash; |
Steven Rostedt (VMware) | d2afd57a | 2017-04-20 11:31:35 -0400 | [diff] [blame] | 4845 | struct trace_array *tr = iter->ops->private; |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4846 | char *func, *command, *next = buff; |
Steven Rostedt | 6a24a24 | 2009-02-17 11:20:26 -0500 | [diff] [blame] | 4847 | struct ftrace_func_command *p; |
GuoWen Li | 0aff1c0 | 2011-06-01 19:18:47 +0800 | [diff] [blame] | 4848 | int ret = -EINVAL; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4849 | |
| 4850 | func = strsep(&next, ":"); |
| 4851 | |
| 4852 | if (!next) { |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 4853 | ret = ftrace_match_records(hash, func, len); |
Steven Rostedt | b448c4e | 2011-04-29 15:12:32 -0400 | [diff] [blame] | 4854 | if (!ret) |
| 4855 | ret = -EINVAL; |
| 4856 | if (ret < 0) |
| 4857 | return ret; |
| 4858 | return 0; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4859 | } |
| 4860 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4861 | /* command found */ |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4862 | |
| 4863 | command = strsep(&next, ":"); |
| 4864 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4865 | mutex_lock(&ftrace_cmd_mutex); |
| 4866 | list_for_each_entry(p, &ftrace_commands, list) { |
| 4867 | if (strcmp(p->name, command) == 0) { |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4868 | ret = p->func(tr, hash, func, command, next, enable); |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4869 | goto out_unlock; |
| 4870 | } |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4871 | } |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4872 | out_unlock: |
| 4873 | mutex_unlock(&ftrace_cmd_mutex); |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4874 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame] | 4875 | return ret; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 4876 | } |
| 4877 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 4878 | static ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4879 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
| 4880 | size_t cnt, loff_t *ppos, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4881 | { |
| 4882 | struct ftrace_iterator *iter; |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 4883 | struct trace_parser *parser; |
| 4884 | ssize_t ret, read; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4885 | |
Li Zefan | 4ba7978 | 2009-09-22 13:52:20 +0800 | [diff] [blame] | 4886 | if (!cnt) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4887 | return 0; |
| 4888 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4889 | if (file->f_mode & FMODE_READ) { |
| 4890 | struct seq_file *m = file->private_data; |
| 4891 | iter = m->private; |
| 4892 | } else |
| 4893 | iter = file->private_data; |
| 4894 | |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 4895 | if (unlikely(ftrace_disabled)) |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4896 | return -ENODEV; |
| 4897 | |
| 4898 | /* iter->hash is a local copy, so we don't need regex_lock */ |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 4899 | |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 4900 | parser = &iter->parser; |
| 4901 | read = trace_get_user(parser, ubuf, cnt, ppos); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4902 | |
Li Zefan | 4ba7978 | 2009-09-22 13:52:20 +0800 | [diff] [blame] | 4903 | if (read >= 0 && trace_parser_loaded(parser) && |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 4904 | !trace_parser_cont(parser)) { |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 4905 | ret = ftrace_process_regex(iter, parser->buffer, |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 4906 | parser->idx, enable); |
Li Zefan | 313254a | 2009-12-08 11:15:30 +0800 | [diff] [blame] | 4907 | trace_parser_clear(parser); |
Steven Rostedt (Red Hat) | 7c088b5 | 2013-05-09 11:35:12 -0400 | [diff] [blame] | 4908 | if (ret < 0) |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4909 | goto out; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4910 | } |
| 4911 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4912 | ret = read; |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4913 | out: |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 4914 | return ret; |
| 4915 | } |
| 4916 | |
Steven Rostedt | fc13cb0 | 2011-12-19 14:41:25 -0500 | [diff] [blame] | 4917 | ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4918 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
| 4919 | size_t cnt, loff_t *ppos) |
| 4920 | { |
| 4921 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); |
| 4922 | } |
| 4923 | |
Steven Rostedt | fc13cb0 | 2011-12-19 14:41:25 -0500 | [diff] [blame] | 4924 | ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4925 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
| 4926 | size_t cnt, loff_t *ppos) |
| 4927 | { |
| 4928 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); |
| 4929 | } |
| 4930 | |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4931 | static int |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 4932 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
| 4933 | { |
| 4934 | struct ftrace_func_entry *entry; |
| 4935 | |
| 4936 | if (!ftrace_location(ip)) |
| 4937 | return -EINVAL; |
| 4938 | |
| 4939 | if (remove) { |
| 4940 | entry = ftrace_lookup_ip(hash, ip); |
| 4941 | if (!entry) |
| 4942 | return -ENOENT; |
| 4943 | free_hash_entry(hash, entry); |
| 4944 | return 0; |
| 4945 | } |
| 4946 | |
| 4947 | return add_hash_entry(hash, ip); |
| 4948 | } |
| 4949 | |
| 4950 | static int |
| 4951 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, |
| 4952 | unsigned long ip, int remove, int reset, int enable) |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4953 | { |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4954 | struct ftrace_hash **orig_hash; |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 4955 | struct ftrace_hash *hash; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4956 | int ret; |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 4957 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4958 | if (unlikely(ftrace_disabled)) |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4959 | return -ENODEV; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4960 | |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 4961 | mutex_lock(&ops->func_hash->regex_lock); |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4962 | |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 4963 | if (enable) |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 4964 | orig_hash = &ops->func_hash->filter_hash; |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 4965 | else |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 4966 | orig_hash = &ops->func_hash->notrace_hash; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4967 | |
Wang Nan | b972cc5 | 2014-07-15 08:40:20 +0800 | [diff] [blame] | 4968 | if (reset) |
| 4969 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
| 4970 | else |
| 4971 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); |
| 4972 | |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 4973 | if (!hash) { |
| 4974 | ret = -ENOMEM; |
| 4975 | goto out_regex_unlock; |
| 4976 | } |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 4977 | |
Jiri Olsa | ac483c4 | 2012-01-02 10:04:14 +0100 | [diff] [blame] | 4978 | if (buf && !ftrace_match_records(hash, buf, len)) { |
| 4979 | ret = -EINVAL; |
| 4980 | goto out_regex_unlock; |
| 4981 | } |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 4982 | if (ip) { |
| 4983 | ret = ftrace_match_addr(hash, ip, remove); |
| 4984 | if (ret < 0) |
| 4985 | goto out_regex_unlock; |
| 4986 | } |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4987 | |
| 4988 | mutex_lock(&ftrace_lock); |
Steven Rostedt (VMware) | e16b35d | 2017-04-04 14:46:56 -0400 | [diff] [blame] | 4989 | ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4990 | mutex_unlock(&ftrace_lock); |
| 4991 | |
Jiri Olsa | ac483c4 | 2012-01-02 10:04:14 +0100 | [diff] [blame] | 4992 | out_regex_unlock: |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 4993 | mutex_unlock(&ops->func_hash->regex_lock); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 4994 | |
| 4995 | free_ftrace_hash(hash); |
| 4996 | return ret; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 4997 | } |
| 4998 | |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 4999 | static int |
| 5000 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, |
| 5001 | int reset, int enable) |
| 5002 | { |
Hariprasad Kelam | 9efb85c | 2019-03-24 00:05:23 +0530 | [diff] [blame] | 5003 | return ftrace_set_hash(ops, NULL, 0, ip, remove, reset, enable); |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 5004 | } |
| 5005 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5006 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5007 | |
| 5008 | struct ftrace_direct_func { |
| 5009 | struct list_head next; |
| 5010 | unsigned long addr; |
| 5011 | int count; |
| 5012 | }; |
| 5013 | |
| 5014 | static LIST_HEAD(ftrace_direct_funcs); |
| 5015 | |
| 5016 | /** |
| 5017 | * ftrace_find_direct_func - test an address if it is a registered direct caller |
| 5018 | * @addr: The address of a registered direct caller |
| 5019 | * |
| 5020 | * This searches to see if a ftrace direct caller has been registered |
| 5021 | * at a specific address, and if so, it returns a descriptor for it. |
| 5022 | * |
| 5023 | * This can be used by architecture code to see if an address is |
| 5024 | * a direct caller (trampoline) attached to a fentry/mcount location. |
| 5025 | * This is useful for the function_graph tracer, as it may need to |
| 5026 | * do adjustments if it traced a location that also has a direct |
| 5027 | * trampoline attached to it. |
| 5028 | */ |
| 5029 | struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr) |
| 5030 | { |
| 5031 | struct ftrace_direct_func *entry; |
| 5032 | bool found = false; |
| 5033 | |
| 5034 | /* May be called by fgraph trampoline (protected by rcu tasks) */ |
| 5035 | list_for_each_entry_rcu(entry, &ftrace_direct_funcs, next) { |
| 5036 | if (entry->addr == addr) { |
| 5037 | found = true; |
| 5038 | break; |
| 5039 | } |
| 5040 | } |
| 5041 | if (found) |
| 5042 | return entry; |
| 5043 | |
| 5044 | return NULL; |
| 5045 | } |
| 5046 | |
Alexei Starovoitov | 8a141dd | 2021-03-16 12:58:15 -0700 | [diff] [blame] | 5047 | static struct ftrace_direct_func *ftrace_alloc_direct_func(unsigned long addr) |
| 5048 | { |
| 5049 | struct ftrace_direct_func *direct; |
| 5050 | |
| 5051 | direct = kmalloc(sizeof(*direct), GFP_KERNEL); |
| 5052 | if (!direct) |
| 5053 | return NULL; |
| 5054 | direct->addr = addr; |
| 5055 | direct->count = 0; |
| 5056 | list_add_rcu(&direct->next, &ftrace_direct_funcs); |
| 5057 | ftrace_direct_func_count++; |
| 5058 | return direct; |
| 5059 | } |
| 5060 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5061 | /** |
| 5062 | * register_ftrace_direct - Call a custom trampoline directly |
| 5063 | * @ip: The address of the nop at the beginning of a function |
| 5064 | * @addr: The address of the trampoline to call at @ip |
| 5065 | * |
| 5066 | * This is used to connect a direct call from the nop location (@ip) |
| 5067 | * at the start of ftrace traced functions. The location that it calls |
| 5068 | * (@addr) must be able to handle a direct call, and save the parameters |
| 5069 | * of the function being traced, and restore them (or inject new ones |
| 5070 | * if needed), before returning. |
| 5071 | * |
| 5072 | * Returns: |
| 5073 | * 0 on success |
| 5074 | * -EBUSY - Another direct function is already attached (there can be only one) |
| 5075 | * -ENODEV - @ip does not point to a ftrace nop location (or not supported) |
| 5076 | * -ENOMEM - There was an allocation failure. |
| 5077 | */ |
| 5078 | int register_ftrace_direct(unsigned long ip, unsigned long addr) |
| 5079 | { |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5080 | struct ftrace_direct_func *direct; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5081 | struct ftrace_func_entry *entry; |
| 5082 | struct ftrace_hash *free_hash = NULL; |
| 5083 | struct dyn_ftrace *rec; |
| 5084 | int ret = -EBUSY; |
| 5085 | |
| 5086 | mutex_lock(&direct_mutex); |
| 5087 | |
| 5088 | /* See if there's a direct function at @ip already */ |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 5089 | if (ftrace_find_rec_direct(ip)) |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5090 | goto out_unlock; |
| 5091 | |
| 5092 | ret = -ENODEV; |
| 5093 | rec = lookup_rec(ip, ip); |
| 5094 | if (!rec) |
| 5095 | goto out_unlock; |
| 5096 | |
| 5097 | /* |
| 5098 | * Check if the rec says it has a direct call but we didn't |
| 5099 | * find one earlier? |
| 5100 | */ |
| 5101 | if (WARN_ON(rec->flags & FTRACE_FL_DIRECT)) |
| 5102 | goto out_unlock; |
| 5103 | |
| 5104 | /* Make sure the ip points to the exact record */ |
Steven Rostedt (VMware) | 406acdd | 2019-11-15 14:19:04 -0500 | [diff] [blame] | 5105 | if (ip != rec->ip) { |
| 5106 | ip = rec->ip; |
| 5107 | /* Need to check this ip for a direct. */ |
Alexei Starovoitov | ff20576 | 2019-12-08 16:01:12 -0800 | [diff] [blame] | 5108 | if (ftrace_find_rec_direct(ip)) |
Steven Rostedt (VMware) | 406acdd | 2019-11-15 14:19:04 -0500 | [diff] [blame] | 5109 | goto out_unlock; |
| 5110 | } |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5111 | |
| 5112 | ret = -ENOMEM; |
| 5113 | if (ftrace_hash_empty(direct_functions) || |
| 5114 | direct_functions->count > 2 * (1 << direct_functions->size_bits)) { |
| 5115 | struct ftrace_hash *new_hash; |
| 5116 | int size = ftrace_hash_empty(direct_functions) ? 0 : |
| 5117 | direct_functions->count + 1; |
| 5118 | |
| 5119 | if (size < 32) |
| 5120 | size = 32; |
| 5121 | |
| 5122 | new_hash = dup_hash(direct_functions, size); |
| 5123 | if (!new_hash) |
| 5124 | goto out_unlock; |
| 5125 | |
| 5126 | free_hash = direct_functions; |
| 5127 | direct_functions = new_hash; |
| 5128 | } |
| 5129 | |
| 5130 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); |
| 5131 | if (!entry) |
| 5132 | goto out_unlock; |
| 5133 | |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5134 | direct = ftrace_find_direct_func(addr); |
| 5135 | if (!direct) { |
Alexei Starovoitov | 8a141dd | 2021-03-16 12:58:15 -0700 | [diff] [blame] | 5136 | direct = ftrace_alloc_direct_func(addr); |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5137 | if (!direct) { |
| 5138 | kfree(entry); |
| 5139 | goto out_unlock; |
| 5140 | } |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5141 | } |
| 5142 | |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5143 | entry->ip = ip; |
| 5144 | entry->direct = addr; |
| 5145 | __add_hash_entry(direct_functions, entry); |
| 5146 | |
| 5147 | ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0); |
| 5148 | if (ret) |
| 5149 | remove_hash_entry(direct_functions, entry); |
| 5150 | |
| 5151 | if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) { |
| 5152 | ret = register_ftrace_function(&direct_ops); |
| 5153 | if (ret) |
| 5154 | ftrace_set_filter_ip(&direct_ops, ip, 1, 0); |
| 5155 | } |
| 5156 | |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5157 | if (ret) { |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5158 | kfree(entry); |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5159 | if (!direct->count) { |
| 5160 | list_del_rcu(&direct->next); |
| 5161 | synchronize_rcu_tasks(); |
| 5162 | kfree(direct); |
| 5163 | if (free_hash) |
| 5164 | free_ftrace_hash(free_hash); |
| 5165 | free_hash = NULL; |
Steven Rostedt (VMware) | a3ad1a7 | 2019-11-08 13:12:57 -0500 | [diff] [blame] | 5166 | ftrace_direct_func_count--; |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5167 | } |
| 5168 | } else { |
Steven Rostedt (VMware) | 1c7f9b6 | 2019-11-15 14:13:20 -0500 | [diff] [blame] | 5169 | direct->count++; |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5170 | } |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5171 | out_unlock: |
| 5172 | mutex_unlock(&direct_mutex); |
| 5173 | |
| 5174 | if (free_hash) { |
| 5175 | synchronize_rcu_tasks(); |
| 5176 | free_ftrace_hash(free_hash); |
| 5177 | } |
| 5178 | |
| 5179 | return ret; |
| 5180 | } |
| 5181 | EXPORT_SYMBOL_GPL(register_ftrace_direct); |
| 5182 | |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5183 | static struct ftrace_func_entry *find_direct_entry(unsigned long *ip, |
| 5184 | struct dyn_ftrace **recp) |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5185 | { |
| 5186 | struct ftrace_func_entry *entry; |
| 5187 | struct dyn_ftrace *rec; |
Steven Rostedt (VMware) | 128161f | 2019-11-15 14:14:45 -0500 | [diff] [blame] | 5188 | |
| 5189 | rec = lookup_rec(*ip, *ip); |
| 5190 | if (!rec) |
| 5191 | return NULL; |
| 5192 | |
| 5193 | entry = __ftrace_lookup_ip(direct_functions, rec->ip); |
| 5194 | if (!entry) { |
| 5195 | WARN_ON(rec->flags & FTRACE_FL_DIRECT); |
| 5196 | return NULL; |
| 5197 | } |
| 5198 | |
| 5199 | WARN_ON(!(rec->flags & FTRACE_FL_DIRECT)); |
| 5200 | |
| 5201 | /* Passed in ip just needs to be on the call site */ |
| 5202 | *ip = rec->ip; |
| 5203 | |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5204 | if (recp) |
| 5205 | *recp = rec; |
| 5206 | |
Steven Rostedt (VMware) | 128161f | 2019-11-15 14:14:45 -0500 | [diff] [blame] | 5207 | return entry; |
| 5208 | } |
| 5209 | |
| 5210 | int unregister_ftrace_direct(unsigned long ip, unsigned long addr) |
| 5211 | { |
| 5212 | struct ftrace_direct_func *direct; |
| 5213 | struct ftrace_func_entry *entry; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5214 | int ret = -ENODEV; |
| 5215 | |
| 5216 | mutex_lock(&direct_mutex); |
| 5217 | |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5218 | entry = find_direct_entry(&ip, NULL); |
Steven Rostedt (VMware) | 128161f | 2019-11-15 14:14:45 -0500 | [diff] [blame] | 5219 | if (!entry) |
| 5220 | goto out_unlock; |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5221 | |
| 5222 | if (direct_functions->count == 1) |
| 5223 | unregister_ftrace_function(&direct_ops); |
| 5224 | |
| 5225 | ret = ftrace_set_filter_ip(&direct_ops, ip, 1, 0); |
| 5226 | |
| 5227 | WARN_ON(ret); |
| 5228 | |
| 5229 | remove_hash_entry(direct_functions, entry); |
| 5230 | |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5231 | direct = ftrace_find_direct_func(addr); |
| 5232 | if (!WARN_ON(!direct)) { |
| 5233 | /* This is the good path (see the ! before WARN) */ |
| 5234 | direct->count--; |
| 5235 | WARN_ON(direct->count < 0); |
| 5236 | if (!direct->count) { |
| 5237 | list_del_rcu(&direct->next); |
| 5238 | synchronize_rcu_tasks(); |
| 5239 | kfree(direct); |
Steven Rostedt (VMware) | 353da87 | 2020-04-22 21:38:45 -0400 | [diff] [blame] | 5240 | kfree(entry); |
Steven Rostedt (VMware) | a3ad1a7 | 2019-11-08 13:12:57 -0500 | [diff] [blame] | 5241 | ftrace_direct_func_count--; |
Steven Rostedt (VMware) | 013bf0d | 2019-11-08 13:11:27 -0500 | [diff] [blame] | 5242 | } |
| 5243 | } |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5244 | out_unlock: |
| 5245 | mutex_unlock(&direct_mutex); |
| 5246 | |
| 5247 | return ret; |
| 5248 | } |
| 5249 | EXPORT_SYMBOL_GPL(unregister_ftrace_direct); |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5250 | |
| 5251 | static struct ftrace_ops stub_ops = { |
| 5252 | .func = ftrace_stub, |
| 5253 | }; |
| 5254 | |
| 5255 | /** |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5256 | * ftrace_modify_direct_caller - modify ftrace nop directly |
| 5257 | * @entry: The ftrace hash entry of the direct helper for @rec |
| 5258 | * @rec: The record representing the function site to patch |
| 5259 | * @old_addr: The location that the site at @rec->ip currently calls |
| 5260 | * @new_addr: The location that the site at @rec->ip should call |
| 5261 | * |
| 5262 | * An architecture may overwrite this function to optimize the |
| 5263 | * changing of the direct callback on an ftrace nop location. |
| 5264 | * This is called with the ftrace_lock mutex held, and no other |
| 5265 | * ftrace callbacks are on the associated record (@rec). Thus, |
| 5266 | * it is safe to modify the ftrace record, where it should be |
| 5267 | * currently calling @old_addr directly, to call @new_addr. |
| 5268 | * |
| 5269 | * Safety checks should be made to make sure that the code at |
| 5270 | * @rec->ip is currently calling @old_addr. And this must |
| 5271 | * also update entry->direct to @new_addr. |
| 5272 | */ |
| 5273 | int __weak ftrace_modify_direct_caller(struct ftrace_func_entry *entry, |
| 5274 | struct dyn_ftrace *rec, |
| 5275 | unsigned long old_addr, |
| 5276 | unsigned long new_addr) |
| 5277 | { |
| 5278 | unsigned long ip = rec->ip; |
| 5279 | int ret; |
| 5280 | |
| 5281 | /* |
| 5282 | * The ftrace_lock was used to determine if the record |
| 5283 | * had more than one registered user to it. If it did, |
| 5284 | * we needed to prevent that from changing to do the quick |
| 5285 | * switch. But if it did not (only a direct caller was attached) |
| 5286 | * then this function is called. But this function can deal |
| 5287 | * with attached callers to the rec that we care about, and |
| 5288 | * since this function uses standard ftrace calls that take |
| 5289 | * the ftrace_lock mutex, we need to release it. |
| 5290 | */ |
| 5291 | mutex_unlock(&ftrace_lock); |
| 5292 | |
| 5293 | /* |
| 5294 | * By setting a stub function at the same address, we force |
| 5295 | * the code to call the iterator and the direct_ops helper. |
| 5296 | * This means that @ip does not call the direct call, and |
| 5297 | * we can simply modify it. |
| 5298 | */ |
| 5299 | ret = ftrace_set_filter_ip(&stub_ops, ip, 0, 0); |
| 5300 | if (ret) |
| 5301 | goto out_lock; |
| 5302 | |
| 5303 | ret = register_ftrace_function(&stub_ops); |
| 5304 | if (ret) { |
| 5305 | ftrace_set_filter_ip(&stub_ops, ip, 1, 0); |
| 5306 | goto out_lock; |
| 5307 | } |
| 5308 | |
| 5309 | entry->direct = new_addr; |
| 5310 | |
| 5311 | /* |
| 5312 | * By removing the stub, we put back the direct call, calling |
| 5313 | * the @new_addr. |
| 5314 | */ |
| 5315 | unregister_ftrace_function(&stub_ops); |
| 5316 | ftrace_set_filter_ip(&stub_ops, ip, 1, 0); |
| 5317 | |
| 5318 | out_lock: |
| 5319 | mutex_lock(&ftrace_lock); |
| 5320 | |
| 5321 | return ret; |
| 5322 | } |
| 5323 | |
| 5324 | /** |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5325 | * modify_ftrace_direct - Modify an existing direct call to call something else |
| 5326 | * @ip: The instruction pointer to modify |
| 5327 | * @old_addr: The address that the current @ip calls directly |
| 5328 | * @new_addr: The address that the @ip should call |
| 5329 | * |
| 5330 | * This modifies a ftrace direct caller at an instruction pointer without |
| 5331 | * having to disable it first. The direct call will switch over to the |
| 5332 | * @new_addr without missing anything. |
| 5333 | * |
| 5334 | * Returns: zero on success. Non zero on error, which includes: |
| 5335 | * -ENODEV : the @ip given has no direct caller attached |
| 5336 | * -EINVAL : the @old_addr does not match the current direct caller |
| 5337 | */ |
| 5338 | int modify_ftrace_direct(unsigned long ip, |
| 5339 | unsigned long old_addr, unsigned long new_addr) |
| 5340 | { |
Alexei Starovoitov | 8a141dd | 2021-03-16 12:58:15 -0700 | [diff] [blame] | 5341 | struct ftrace_direct_func *direct, *new_direct = NULL; |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5342 | struct ftrace_func_entry *entry; |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5343 | struct dyn_ftrace *rec; |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5344 | int ret = -ENODEV; |
| 5345 | |
| 5346 | mutex_lock(&direct_mutex); |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5347 | |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5348 | mutex_lock(&ftrace_lock); |
| 5349 | entry = find_direct_entry(&ip, &rec); |
Steven Rostedt (VMware) | 128161f | 2019-11-15 14:14:45 -0500 | [diff] [blame] | 5350 | if (!entry) |
| 5351 | goto out_unlock; |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5352 | |
| 5353 | ret = -EINVAL; |
| 5354 | if (entry->direct != old_addr) |
| 5355 | goto out_unlock; |
| 5356 | |
Alexei Starovoitov | 8a141dd | 2021-03-16 12:58:15 -0700 | [diff] [blame] | 5357 | direct = ftrace_find_direct_func(old_addr); |
| 5358 | if (WARN_ON(!direct)) |
| 5359 | goto out_unlock; |
| 5360 | if (direct->count > 1) { |
| 5361 | ret = -ENOMEM; |
| 5362 | new_direct = ftrace_alloc_direct_func(new_addr); |
| 5363 | if (!new_direct) |
| 5364 | goto out_unlock; |
| 5365 | direct->count--; |
| 5366 | new_direct->count++; |
| 5367 | } else { |
| 5368 | direct->addr = new_addr; |
| 5369 | } |
| 5370 | |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5371 | /* |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5372 | * If there's no other ftrace callback on the rec->ip location, |
| 5373 | * then it can be changed directly by the architecture. |
| 5374 | * If there is another caller, then we just need to change the |
| 5375 | * direct caller helper to point to @new_addr. |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5376 | */ |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5377 | if (ftrace_rec_count(rec) == 1) { |
| 5378 | ret = ftrace_modify_direct_caller(entry, rec, old_addr, new_addr); |
| 5379 | } else { |
| 5380 | entry->direct = new_addr; |
| 5381 | ret = 0; |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5382 | } |
| 5383 | |
Alexei Starovoitov | 8a141dd | 2021-03-16 12:58:15 -0700 | [diff] [blame] | 5384 | if (unlikely(ret && new_direct)) { |
| 5385 | direct->count++; |
| 5386 | list_del_rcu(&new_direct->next); |
| 5387 | synchronize_rcu_tasks(); |
| 5388 | kfree(new_direct); |
| 5389 | ftrace_direct_func_count--; |
| 5390 | } |
| 5391 | |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5392 | out_unlock: |
Steven Rostedt (VMware) | ea806eb | 2019-11-17 17:04:15 -0500 | [diff] [blame] | 5393 | mutex_unlock(&ftrace_lock); |
Steven Rostedt (VMware) | 0567d68 | 2019-11-14 14:39:35 -0500 | [diff] [blame] | 5394 | mutex_unlock(&direct_mutex); |
| 5395 | return ret; |
| 5396 | } |
| 5397 | EXPORT_SYMBOL_GPL(modify_ftrace_direct); |
Steven Rostedt (VMware) | 763e34e7 | 2019-11-08 13:07:06 -0500 | [diff] [blame] | 5398 | #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ |
| 5399 | |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 5400 | /** |
| 5401 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address |
| 5402 | * @ops - the ops to set the filter with |
| 5403 | * @ip - the address to add to or remove from the filter. |
| 5404 | * @remove - non zero to remove the ip from the filter |
| 5405 | * @reset - non zero to reset all filters before applying this filter. |
| 5406 | * |
| 5407 | * Filters denote which functions should be enabled when tracing is enabled |
Ingo Molnar | f2cc020 | 2021-03-23 18:49:35 +0100 | [diff] [blame] | 5408 | * If @ip is NULL, it fails to update filter. |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 5409 | */ |
| 5410 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, |
| 5411 | int remove, int reset) |
| 5412 | { |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 5413 | ftrace_ops_init(ops); |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 5414 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
| 5415 | } |
| 5416 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); |
| 5417 | |
Joel Fernandes | d032ae8 | 2016-11-15 12:31:20 -0800 | [diff] [blame] | 5418 | /** |
| 5419 | * ftrace_ops_set_global_filter - setup ops to use global filters |
| 5420 | * @ops - the ops which will use the global filters |
| 5421 | * |
| 5422 | * ftrace users who need global function trace filtering should call this. |
| 5423 | * It can set the global filter only if ops were not initialized before. |
| 5424 | */ |
| 5425 | void ftrace_ops_set_global_filter(struct ftrace_ops *ops) |
| 5426 | { |
| 5427 | if (ops->flags & FTRACE_OPS_FL_INITIALIZED) |
| 5428 | return; |
| 5429 | |
| 5430 | ftrace_ops_init(ops); |
| 5431 | ops->func_hash = &global_ops.local_hash; |
| 5432 | } |
| 5433 | EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter); |
| 5434 | |
Masami Hiramatsu | 647664e | 2012-06-05 19:28:08 +0900 | [diff] [blame] | 5435 | static int |
| 5436 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, |
| 5437 | int reset, int enable) |
| 5438 | { |
| 5439 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); |
| 5440 | } |
| 5441 | |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 5442 | /** |
| 5443 | * ftrace_set_filter - set a function to filter on in ftrace |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5444 | * @ops - the ops to set the filter with |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 5445 | * @buf - the string that holds the function filter text. |
| 5446 | * @len - the length of the string. |
| 5447 | * @reset - non zero to reset all filters before applying this filter. |
| 5448 | * |
| 5449 | * Filters denote which functions should be enabled when tracing is enabled. |
| 5450 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. |
| 5451 | */ |
Jiri Olsa | ac483c4 | 2012-01-02 10:04:14 +0100 | [diff] [blame] | 5452 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5453 | int len, int reset) |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 5454 | { |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 5455 | ftrace_ops_init(ops); |
Jiri Olsa | ac483c4 | 2012-01-02 10:04:14 +0100 | [diff] [blame] | 5456 | return ftrace_set_regex(ops, buf, len, reset, 1); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5457 | } |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5458 | EXPORT_SYMBOL_GPL(ftrace_set_filter); |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 5459 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5460 | /** |
| 5461 | * ftrace_set_notrace - set a function to not trace in ftrace |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5462 | * @ops - the ops to set the notrace filter with |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5463 | * @buf - the string that holds the function notrace text. |
| 5464 | * @len - the length of the string. |
| 5465 | * @reset - non zero to reset all filters before applying this filter. |
| 5466 | * |
| 5467 | * Notrace Filters denote which functions should not be enabled when tracing |
| 5468 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled |
| 5469 | * for tracing. |
| 5470 | */ |
Jiri Olsa | ac483c4 | 2012-01-02 10:04:14 +0100 | [diff] [blame] | 5471 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5472 | int len, int reset) |
| 5473 | { |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 5474 | ftrace_ops_init(ops); |
Jiri Olsa | ac483c4 | 2012-01-02 10:04:14 +0100 | [diff] [blame] | 5475 | return ftrace_set_regex(ops, buf, len, reset, 0); |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5476 | } |
| 5477 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); |
| 5478 | /** |
Jiaxing Wang | 8d1b065 | 2014-04-20 23:10:44 +0800 | [diff] [blame] | 5479 | * ftrace_set_global_filter - set a function to filter on with global tracers |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5480 | * @buf - the string that holds the function filter text. |
| 5481 | * @len - the length of the string. |
| 5482 | * @reset - non zero to reset all filters before applying this filter. |
| 5483 | * |
| 5484 | * Filters denote which functions should be enabled when tracing is enabled. |
| 5485 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. |
| 5486 | */ |
| 5487 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
| 5488 | { |
| 5489 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
| 5490 | } |
| 5491 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
| 5492 | |
| 5493 | /** |
Jiaxing Wang | 8d1b065 | 2014-04-20 23:10:44 +0800 | [diff] [blame] | 5494 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5495 | * @buf - the string that holds the function notrace text. |
| 5496 | * @len - the length of the string. |
| 5497 | * @reset - non zero to reset all filters before applying this filter. |
| 5498 | * |
| 5499 | * Notrace Filters denote which functions should not be enabled when tracing |
| 5500 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled |
| 5501 | * for tracing. |
| 5502 | */ |
| 5503 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5504 | { |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 5505 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 5506 | } |
Steven Rostedt | 936e074 | 2011-05-05 22:54:01 -0400 | [diff] [blame] | 5507 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 5508 | |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5509 | /* |
| 5510 | * command line interface to allow users to set filters on boot up. |
| 5511 | */ |
| 5512 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE |
| 5513 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
| 5514 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; |
| 5515 | |
Steven Rostedt (Red Hat) | f1ed7c7 | 2013-06-27 22:18:06 -0400 | [diff] [blame] | 5516 | /* Used by function selftest to not test if filter is set */ |
| 5517 | bool ftrace_filter_param __initdata; |
| 5518 | |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5519 | static int __init set_ftrace_notrace(char *str) |
| 5520 | { |
Steven Rostedt (Red Hat) | f1ed7c7 | 2013-06-27 22:18:06 -0400 | [diff] [blame] | 5521 | ftrace_filter_param = true; |
Chen Gang | 75761cc | 2013-04-08 12:12:39 +0800 | [diff] [blame] | 5522 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5523 | return 1; |
| 5524 | } |
| 5525 | __setup("ftrace_notrace=", set_ftrace_notrace); |
| 5526 | |
| 5527 | static int __init set_ftrace_filter(char *str) |
| 5528 | { |
Steven Rostedt (Red Hat) | f1ed7c7 | 2013-06-27 22:18:06 -0400 | [diff] [blame] | 5529 | ftrace_filter_param = true; |
Chen Gang | 75761cc | 2013-04-08 12:12:39 +0800 | [diff] [blame] | 5530 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5531 | return 1; |
| 5532 | } |
| 5533 | __setup("ftrace_filter=", set_ftrace_filter); |
| 5534 | |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5535 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Lai Jiangshan | f6060f4 | 2009-11-05 11:16:17 +0800 | [diff] [blame] | 5536 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
Namhyung Kim | 0d7d9a1 | 2014-06-13 01:23:50 +0900 | [diff] [blame] | 5537 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5538 | static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); |
Steven Rostedt | 801c29f | 2010-03-05 20:02:19 -0500 | [diff] [blame] | 5539 | |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5540 | static int __init set_graph_function(char *str) |
| 5541 | { |
Frederic Weisbecker | 06f43d6 | 2009-10-14 20:43:39 +0200 | [diff] [blame] | 5542 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5543 | return 1; |
| 5544 | } |
| 5545 | __setup("ftrace_graph_filter=", set_graph_function); |
| 5546 | |
Namhyung Kim | 0d7d9a1 | 2014-06-13 01:23:50 +0900 | [diff] [blame] | 5547 | static int __init set_graph_notrace_function(char *str) |
| 5548 | { |
| 5549 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); |
| 5550 | return 1; |
| 5551 | } |
| 5552 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); |
| 5553 | |
Todd Brandt | 65a50c6 | 2017-03-02 16:12:15 -0800 | [diff] [blame] | 5554 | static int __init set_graph_max_depth_function(char *str) |
| 5555 | { |
| 5556 | if (!str) |
| 5557 | return 0; |
| 5558 | fgraph_max_depth = simple_strtoul(str, NULL, 0); |
| 5559 | return 1; |
| 5560 | } |
| 5561 | __setup("ftrace_graph_max_depth=", set_graph_max_depth_function); |
| 5562 | |
Namhyung Kim | 0d7d9a1 | 2014-06-13 01:23:50 +0900 | [diff] [blame] | 5563 | static void __init set_ftrace_early_graph(char *buf, int enable) |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5564 | { |
| 5565 | int ret; |
| 5566 | char *func; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5567 | struct ftrace_hash *hash; |
Namhyung Kim | 0d7d9a1 | 2014-06-13 01:23:50 +0900 | [diff] [blame] | 5568 | |
Steven Rostedt (VMware) | 92ad18e | 2017-03-02 12:53:26 -0500 | [diff] [blame] | 5569 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
Steven Rostedt (VMware) | 24589e3 | 2020-01-25 10:52:30 -0500 | [diff] [blame] | 5570 | if (MEM_FAIL(!hash, "Failed to allocate hash\n")) |
Steven Rostedt (VMware) | 92ad18e | 2017-03-02 12:53:26 -0500 | [diff] [blame] | 5571 | return; |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5572 | |
| 5573 | while (buf) { |
| 5574 | func = strsep(&buf, ","); |
| 5575 | /* we allow only one expression at a time */ |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5576 | ret = ftrace_graph_set_hash(hash, func); |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5577 | if (ret) |
| 5578 | printk(KERN_DEBUG "ftrace: function %s not " |
| 5579 | "traceable\n", func); |
| 5580 | } |
Steven Rostedt (VMware) | 92ad18e | 2017-03-02 12:53:26 -0500 | [diff] [blame] | 5581 | |
| 5582 | if (enable) |
| 5583 | ftrace_graph_hash = hash; |
| 5584 | else |
| 5585 | ftrace_graph_notrace_hash = hash; |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5586 | } |
| 5587 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
| 5588 | |
Steven Rostedt | 2a85a37 | 2011-12-19 21:57:44 -0500 | [diff] [blame] | 5589 | void __init |
| 5590 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5591 | { |
| 5592 | char *func; |
| 5593 | |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 5594 | ftrace_ops_init(ops); |
| 5595 | |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5596 | while (buf) { |
| 5597 | func = strsep(&buf, ","); |
Steven Rostedt | f45948e | 2011-05-02 12:29:25 -0400 | [diff] [blame] | 5598 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5599 | } |
| 5600 | } |
| 5601 | |
| 5602 | static void __init set_ftrace_early_filters(void) |
| 5603 | { |
| 5604 | if (ftrace_filter_buf[0]) |
Steven Rostedt | 2a85a37 | 2011-12-19 21:57:44 -0500 | [diff] [blame] | 5605 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5606 | if (ftrace_notrace_buf[0]) |
Steven Rostedt | 2a85a37 | 2011-12-19 21:57:44 -0500 | [diff] [blame] | 5607 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5608 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| 5609 | if (ftrace_graph_buf[0]) |
Namhyung Kim | 0d7d9a1 | 2014-06-13 01:23:50 +0900 | [diff] [blame] | 5610 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
| 5611 | if (ftrace_graph_notrace_buf[0]) |
| 5612 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); |
Stefan Assmann | 369bc18 | 2009-10-12 22:17:21 +0200 | [diff] [blame] | 5613 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 5614 | } |
| 5615 | |
Steven Rostedt | fc13cb0 | 2011-12-19 14:41:25 -0500 | [diff] [blame] | 5616 | int ftrace_regex_release(struct inode *inode, struct file *file) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5617 | { |
| 5618 | struct seq_file *m = (struct seq_file *)file->private_data; |
| 5619 | struct ftrace_iterator *iter; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 5620 | struct ftrace_hash **orig_hash; |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 5621 | struct trace_parser *parser; |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 5622 | int filter_hash; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5623 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5624 | if (file->f_mode & FMODE_READ) { |
| 5625 | iter = m->private; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5626 | seq_release(inode, file); |
| 5627 | } else |
| 5628 | iter = file->private_data; |
| 5629 | |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 5630 | parser = &iter->parser; |
| 5631 | if (trace_parser_loaded(parser)) { |
Steven Rostedt (VMware) | 8c9af47 | 2021-05-05 10:38:24 -0400 | [diff] [blame] | 5632 | int enable = !(iter->flags & FTRACE_ITER_NOTRACE); |
| 5633 | |
| 5634 | ftrace_process_regex(iter, parser->buffer, |
| 5635 | parser->idx, enable); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5636 | } |
| 5637 | |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 5638 | trace_parser_put(parser); |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 5639 | |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 5640 | mutex_lock(&iter->ops->func_hash->regex_lock); |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 5641 | |
Steven Rostedt | 058e297 | 2011-04-29 22:35:33 -0400 | [diff] [blame] | 5642 | if (file->f_mode & FMODE_WRITE) { |
Steven Rostedt | ed926f9 | 2011-05-03 13:25:24 -0400 | [diff] [blame] | 5643 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
| 5644 | |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 5645 | if (filter_hash) { |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 5646 | orig_hash = &iter->ops->func_hash->filter_hash; |
Steven Rostedt (VMware) | 69d7187 | 2017-07-05 09:45:43 -0400 | [diff] [blame] | 5647 | if (iter->tr && !list_empty(&iter->tr->mod_trace)) |
Steven Rostedt (VMware) | 8c08f0d | 2017-06-26 11:47:31 -0400 | [diff] [blame] | 5648 | iter->hash->flags |= FTRACE_HASH_FL_MOD; |
| 5649 | } else |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 5650 | orig_hash = &iter->ops->func_hash->notrace_hash; |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 5651 | |
Steven Rostedt | 058e297 | 2011-04-29 22:35:33 -0400 | [diff] [blame] | 5652 | mutex_lock(&ftrace_lock); |
Alex Shi | 045e269 | 2020-11-06 22:54:46 +0800 | [diff] [blame] | 5653 | ftrace_hash_move_and_update_ops(iter->ops, orig_hash, |
Steven Rostedt (VMware) | e16b35d | 2017-04-04 14:46:56 -0400 | [diff] [blame] | 5654 | iter->hash, filter_hash); |
Steven Rostedt | 058e297 | 2011-04-29 22:35:33 -0400 | [diff] [blame] | 5655 | mutex_unlock(&ftrace_lock); |
Steven Rostedt (VMware) | c20489d | 2017-03-29 14:55:49 -0400 | [diff] [blame] | 5656 | } else { |
| 5657 | /* For read only, the hash is the ops hash */ |
| 5658 | iter->hash = NULL; |
Steven Rostedt | 058e297 | 2011-04-29 22:35:33 -0400 | [diff] [blame] | 5659 | } |
Masami Hiramatsu | 3f2367b | 2013-05-09 14:44:21 +0900 | [diff] [blame] | 5660 | |
Steven Rostedt (Red Hat) | 33b7f99 | 2014-08-15 17:23:02 -0400 | [diff] [blame] | 5661 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 5662 | free_ftrace_hash(iter->hash); |
Steven Rostedt (VMware) | 9ef1669 | 2019-10-11 17:56:57 -0400 | [diff] [blame] | 5663 | if (iter->tr) |
| 5664 | trace_array_put(iter->tr); |
Steven Rostedt | 33dc9b1 | 2011-05-02 17:34:47 -0400 | [diff] [blame] | 5665 | kfree(iter); |
Steven Rostedt | 058e297 | 2011-04-29 22:35:33 -0400 | [diff] [blame] | 5666 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5667 | return 0; |
| 5668 | } |
| 5669 | |
Steven Rostedt | 5e2336a | 2009-03-05 21:44:55 -0500 | [diff] [blame] | 5670 | static const struct file_operations ftrace_avail_fops = { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5671 | .open = ftrace_avail_open, |
| 5672 | .read = seq_read, |
| 5673 | .llseek = seq_lseek, |
Li Zefan | 3be04b4 | 2009-08-17 16:54:03 +0800 | [diff] [blame] | 5674 | .release = seq_release_private, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5675 | }; |
| 5676 | |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 5677 | static const struct file_operations ftrace_enabled_fops = { |
| 5678 | .open = ftrace_enabled_open, |
| 5679 | .read = seq_read, |
| 5680 | .llseek = seq_lseek, |
| 5681 | .release = seq_release_private, |
| 5682 | }; |
| 5683 | |
Steven Rostedt | 5e2336a | 2009-03-05 21:44:55 -0500 | [diff] [blame] | 5684 | static const struct file_operations ftrace_filter_fops = { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5685 | .open = ftrace_filter_open, |
Lai Jiangshan | 850a80c | 2009-03-13 17:47:23 +0800 | [diff] [blame] | 5686 | .read = seq_read, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5687 | .write = ftrace_filter_write, |
Steven Rostedt (Red Hat) | 098c879e | 2013-12-21 17:39:40 -0500 | [diff] [blame] | 5688 | .llseek = tracing_lseek, |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 5689 | .release = ftrace_regex_release, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 5690 | }; |
| 5691 | |
Steven Rostedt | 5e2336a | 2009-03-05 21:44:55 -0500 | [diff] [blame] | 5692 | static const struct file_operations ftrace_notrace_fops = { |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5693 | .open = ftrace_notrace_open, |
Lai Jiangshan | 850a80c | 2009-03-13 17:47:23 +0800 | [diff] [blame] | 5694 | .read = seq_read, |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5695 | .write = ftrace_notrace_write, |
Steven Rostedt (Red Hat) | 098c879e | 2013-12-21 17:39:40 -0500 | [diff] [blame] | 5696 | .llseek = tracing_lseek, |
Steven Rostedt | 1cf41dd7 | 2011-04-29 20:59:51 -0400 | [diff] [blame] | 5697 | .release = ftrace_regex_release, |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 5698 | }; |
| 5699 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5700 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| 5701 | |
| 5702 | static DEFINE_MUTEX(graph_lock); |
| 5703 | |
Amol Grover | 24a9729 | 2020-02-01 12:57:04 +0530 | [diff] [blame] | 5704 | struct ftrace_hash __rcu *ftrace_graph_hash = EMPTY_HASH; |
Amol Grover | fd0e685 | 2020-02-05 11:27:02 +0530 | [diff] [blame] | 5705 | struct ftrace_hash __rcu *ftrace_graph_notrace_hash = EMPTY_HASH; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5706 | |
| 5707 | enum graph_filter_type { |
| 5708 | GRAPH_FILTER_NOTRACE = 0, |
| 5709 | GRAPH_FILTER_FUNCTION, |
| 5710 | }; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5711 | |
Steven Rostedt (VMware) | 555fc78 | 2017-02-02 10:15:22 -0500 | [diff] [blame] | 5712 | #define FTRACE_GRAPH_EMPTY ((void *)1) |
| 5713 | |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5714 | struct ftrace_graph_data { |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5715 | struct ftrace_hash *hash; |
| 5716 | struct ftrace_func_entry *entry; |
| 5717 | int idx; /* for hash table iteration */ |
| 5718 | enum graph_filter_type type; |
| 5719 | struct ftrace_hash *new_hash; |
| 5720 | const struct seq_operations *seq_ops; |
| 5721 | struct trace_parser parser; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5722 | }; |
| 5723 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5724 | static void * |
Li Zefan | 8595184 | 2009-06-24 09:54:00 +0800 | [diff] [blame] | 5725 | __g_next(struct seq_file *m, loff_t *pos) |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5726 | { |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5727 | struct ftrace_graph_data *fgd = m->private; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5728 | struct ftrace_func_entry *entry = fgd->entry; |
| 5729 | struct hlist_head *head; |
| 5730 | int i, idx = fgd->idx; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5731 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5732 | if (*pos >= fgd->hash->count) |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5733 | return NULL; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5734 | |
| 5735 | if (entry) { |
| 5736 | hlist_for_each_entry_continue(entry, hlist) { |
| 5737 | fgd->entry = entry; |
| 5738 | return entry; |
| 5739 | } |
| 5740 | |
| 5741 | idx++; |
| 5742 | } |
| 5743 | |
| 5744 | for (i = idx; i < 1 << fgd->hash->size_bits; i++) { |
| 5745 | head = &fgd->hash->buckets[i]; |
| 5746 | hlist_for_each_entry(entry, head, hlist) { |
| 5747 | fgd->entry = entry; |
| 5748 | fgd->idx = i; |
| 5749 | return entry; |
| 5750 | } |
| 5751 | } |
| 5752 | return NULL; |
Li Zefan | 8595184 | 2009-06-24 09:54:00 +0800 | [diff] [blame] | 5753 | } |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5754 | |
Li Zefan | 8595184 | 2009-06-24 09:54:00 +0800 | [diff] [blame] | 5755 | static void * |
| 5756 | g_next(struct seq_file *m, void *v, loff_t *pos) |
| 5757 | { |
| 5758 | (*pos)++; |
| 5759 | return __g_next(m, pos); |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5760 | } |
| 5761 | |
| 5762 | static void *g_start(struct seq_file *m, loff_t *pos) |
| 5763 | { |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5764 | struct ftrace_graph_data *fgd = m->private; |
| 5765 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5766 | mutex_lock(&graph_lock); |
| 5767 | |
Steven Rostedt (VMware) | 649b988 | 2017-02-02 20:16:29 -0500 | [diff] [blame] | 5768 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
| 5769 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
| 5770 | lockdep_is_held(&graph_lock)); |
| 5771 | else |
| 5772 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
| 5773 | lockdep_is_held(&graph_lock)); |
| 5774 | |
Frederic Weisbecker | f9349a8 | 2009-02-19 21:13:12 +0100 | [diff] [blame] | 5775 | /* Nothing, tell g_show to print all functions are enabled */ |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5776 | if (ftrace_hash_empty(fgd->hash) && !*pos) |
Steven Rostedt (VMware) | 555fc78 | 2017-02-02 10:15:22 -0500 | [diff] [blame] | 5777 | return FTRACE_GRAPH_EMPTY; |
Frederic Weisbecker | f9349a8 | 2009-02-19 21:13:12 +0100 | [diff] [blame] | 5778 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5779 | fgd->idx = 0; |
| 5780 | fgd->entry = NULL; |
Li Zefan | 8595184 | 2009-06-24 09:54:00 +0800 | [diff] [blame] | 5781 | return __g_next(m, pos); |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5782 | } |
| 5783 | |
| 5784 | static void g_stop(struct seq_file *m, void *p) |
| 5785 | { |
| 5786 | mutex_unlock(&graph_lock); |
| 5787 | } |
| 5788 | |
| 5789 | static int g_show(struct seq_file *m, void *v) |
| 5790 | { |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5791 | struct ftrace_func_entry *entry = v; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5792 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5793 | if (!entry) |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5794 | return 0; |
| 5795 | |
Steven Rostedt (VMware) | 555fc78 | 2017-02-02 10:15:22 -0500 | [diff] [blame] | 5796 | if (entry == FTRACE_GRAPH_EMPTY) { |
Namhyung Kim | 280d142 | 2014-06-13 01:23:51 +0900 | [diff] [blame] | 5797 | struct ftrace_graph_data *fgd = m->private; |
| 5798 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5799 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 5800 | seq_puts(m, "#### all functions enabled ####\n"); |
Namhyung Kim | 280d142 | 2014-06-13 01:23:51 +0900 | [diff] [blame] | 5801 | else |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 5802 | seq_puts(m, "#### no functions disabled ####\n"); |
Frederic Weisbecker | f9349a8 | 2009-02-19 21:13:12 +0100 | [diff] [blame] | 5803 | return 0; |
| 5804 | } |
| 5805 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5806 | seq_printf(m, "%ps\n", (void *)entry->ip); |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5807 | |
| 5808 | return 0; |
| 5809 | } |
| 5810 | |
James Morris | 88e9d34 | 2009-09-22 16:43:43 -0700 | [diff] [blame] | 5811 | static const struct seq_operations ftrace_graph_seq_ops = { |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5812 | .start = g_start, |
| 5813 | .next = g_next, |
| 5814 | .stop = g_stop, |
| 5815 | .show = g_show, |
| 5816 | }; |
| 5817 | |
| 5818 | static int |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5819 | __ftrace_graph_open(struct inode *inode, struct file *file, |
| 5820 | struct ftrace_graph_data *fgd) |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5821 | { |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 5822 | int ret; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5823 | struct ftrace_hash *new_hash = NULL; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5824 | |
Steven Rostedt (VMware) | 17911ff | 2019-10-11 17:22:50 -0400 | [diff] [blame] | 5825 | ret = security_locked_down(LOCKDOWN_TRACEFS); |
| 5826 | if (ret) |
| 5827 | return ret; |
| 5828 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5829 | if (file->f_mode & FMODE_WRITE) { |
| 5830 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
| 5831 | |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5832 | if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX)) |
| 5833 | return -ENOMEM; |
| 5834 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5835 | if (file->f_flags & O_TRUNC) |
| 5836 | new_hash = alloc_ftrace_hash(size_bits); |
| 5837 | else |
| 5838 | new_hash = alloc_and_copy_ftrace_hash(size_bits, |
| 5839 | fgd->hash); |
| 5840 | if (!new_hash) { |
| 5841 | ret = -ENOMEM; |
| 5842 | goto out; |
| 5843 | } |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5844 | } |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5845 | |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5846 | if (file->f_mode & FMODE_READ) { |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5847 | ret = seq_open(file, &ftrace_graph_seq_ops); |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5848 | if (!ret) { |
| 5849 | struct seq_file *m = file->private_data; |
| 5850 | m->private = fgd; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5851 | } else { |
| 5852 | /* Failed */ |
| 5853 | free_ftrace_hash(new_hash); |
| 5854 | new_hash = NULL; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5855 | } |
| 5856 | } else |
| 5857 | file->private_data = fgd; |
Li Zefan | a4ec5e0 | 2009-09-18 14:06:28 +0800 | [diff] [blame] | 5858 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5859 | out: |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5860 | if (ret < 0 && file->f_mode & FMODE_WRITE) |
| 5861 | trace_parser_put(&fgd->parser); |
| 5862 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5863 | fgd->new_hash = new_hash; |
Steven Rostedt (VMware) | 649b988 | 2017-02-02 20:16:29 -0500 | [diff] [blame] | 5864 | |
| 5865 | /* |
| 5866 | * All uses of fgd->hash must be taken with the graph_lock |
| 5867 | * held. The graph_lock is going to be released, so force |
| 5868 | * fgd->hash to be reinitialized when it is taken again. |
| 5869 | */ |
| 5870 | fgd->hash = NULL; |
| 5871 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5872 | return ret; |
| 5873 | } |
| 5874 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 5875 | static int |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5876 | ftrace_graph_open(struct inode *inode, struct file *file) |
| 5877 | { |
| 5878 | struct ftrace_graph_data *fgd; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5879 | int ret; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5880 | |
| 5881 | if (unlikely(ftrace_disabled)) |
| 5882 | return -ENODEV; |
| 5883 | |
| 5884 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); |
| 5885 | if (fgd == NULL) |
| 5886 | return -ENOMEM; |
| 5887 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5888 | mutex_lock(&graph_lock); |
| 5889 | |
Steven Rostedt (VMware) | 649b988 | 2017-02-02 20:16:29 -0500 | [diff] [blame] | 5890 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
| 5891 | lockdep_is_held(&graph_lock)); |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5892 | fgd->type = GRAPH_FILTER_FUNCTION; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5893 | fgd->seq_ops = &ftrace_graph_seq_ops; |
| 5894 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5895 | ret = __ftrace_graph_open(inode, file, fgd); |
| 5896 | if (ret < 0) |
| 5897 | kfree(fgd); |
| 5898 | |
| 5899 | mutex_unlock(&graph_lock); |
| 5900 | return ret; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5901 | } |
| 5902 | |
| 5903 | static int |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 5904 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) |
| 5905 | { |
| 5906 | struct ftrace_graph_data *fgd; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5907 | int ret; |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 5908 | |
| 5909 | if (unlikely(ftrace_disabled)) |
| 5910 | return -ENODEV; |
| 5911 | |
| 5912 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); |
| 5913 | if (fgd == NULL) |
| 5914 | return -ENOMEM; |
| 5915 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5916 | mutex_lock(&graph_lock); |
| 5917 | |
Steven Rostedt (VMware) | 649b988 | 2017-02-02 20:16:29 -0500 | [diff] [blame] | 5918 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
| 5919 | lockdep_is_held(&graph_lock)); |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5920 | fgd->type = GRAPH_FILTER_NOTRACE; |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 5921 | fgd->seq_ops = &ftrace_graph_seq_ops; |
| 5922 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5923 | ret = __ftrace_graph_open(inode, file, fgd); |
| 5924 | if (ret < 0) |
| 5925 | kfree(fgd); |
| 5926 | |
| 5927 | mutex_unlock(&graph_lock); |
| 5928 | return ret; |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 5929 | } |
| 5930 | |
| 5931 | static int |
Li Zefan | 8782711 | 2009-07-23 11:29:11 +0800 | [diff] [blame] | 5932 | ftrace_graph_release(struct inode *inode, struct file *file) |
| 5933 | { |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5934 | struct ftrace_graph_data *fgd; |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5935 | struct ftrace_hash *old_hash, *new_hash; |
| 5936 | struct trace_parser *parser; |
| 5937 | int ret = 0; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5938 | |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5939 | if (file->f_mode & FMODE_READ) { |
| 5940 | struct seq_file *m = file->private_data; |
| 5941 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5942 | fgd = m->private; |
Li Zefan | 8782711 | 2009-07-23 11:29:11 +0800 | [diff] [blame] | 5943 | seq_release(inode, file); |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5944 | } else { |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5945 | fgd = file->private_data; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 5946 | } |
| 5947 | |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5948 | |
| 5949 | if (file->f_mode & FMODE_WRITE) { |
| 5950 | |
| 5951 | parser = &fgd->parser; |
| 5952 | |
| 5953 | if (trace_parser_loaded((parser))) { |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5954 | ret = ftrace_graph_set_hash(fgd->new_hash, |
| 5955 | parser->buffer); |
| 5956 | } |
| 5957 | |
| 5958 | trace_parser_put(parser); |
| 5959 | |
| 5960 | new_hash = __ftrace_hash_move(fgd->new_hash); |
| 5961 | if (!new_hash) { |
| 5962 | ret = -ENOMEM; |
| 5963 | goto out; |
| 5964 | } |
| 5965 | |
| 5966 | mutex_lock(&graph_lock); |
| 5967 | |
| 5968 | if (fgd->type == GRAPH_FILTER_FUNCTION) { |
| 5969 | old_hash = rcu_dereference_protected(ftrace_graph_hash, |
| 5970 | lockdep_is_held(&graph_lock)); |
| 5971 | rcu_assign_pointer(ftrace_graph_hash, new_hash); |
| 5972 | } else { |
| 5973 | old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
| 5974 | lockdep_is_held(&graph_lock)); |
| 5975 | rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); |
| 5976 | } |
| 5977 | |
| 5978 | mutex_unlock(&graph_lock); |
| 5979 | |
Steven Rostedt (VMware) | 54a16ff | 2020-02-05 09:20:32 -0500 | [diff] [blame] | 5980 | /* |
| 5981 | * We need to do a hard force of sched synchronization. |
| 5982 | * This is because we use preempt_disable() to do RCU, but |
| 5983 | * the function tracers can be called where RCU is not watching |
| 5984 | * (like before user_exit()). We can not rely on the RCU |
| 5985 | * infrastructure to do the synchronization, thus we must do it |
| 5986 | * ourselves. |
| 5987 | */ |
Nicolas Saenz Julienne | 68e83498 | 2021-07-21 13:47:26 +0200 | [diff] [blame] | 5988 | if (old_hash != EMPTY_HASH) |
| 5989 | synchronize_rcu_tasks_rude(); |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5990 | |
| 5991 | free_ftrace_hash(old_hash); |
| 5992 | } |
| 5993 | |
| 5994 | out: |
Luis Henriques | f9797c2 | 2017-05-25 16:20:38 +0100 | [diff] [blame] | 5995 | free_ftrace_hash(fgd->new_hash); |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 5996 | kfree(fgd); |
| 5997 | |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 5998 | return ret; |
Li Zefan | 8782711 | 2009-07-23 11:29:11 +0800 | [diff] [blame] | 5999 | } |
| 6000 | |
| 6001 | static int |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 6002 | ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6003 | { |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 6004 | struct ftrace_glob func_g; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6005 | struct dyn_ftrace *rec; |
| 6006 | struct ftrace_page *pg; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 6007 | struct ftrace_func_entry *entry; |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6008 | int fail = 1; |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 6009 | int not; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6010 | |
Frederic Weisbecker | f9349a8 | 2009-02-19 21:13:12 +0100 | [diff] [blame] | 6011 | /* decode regex */ |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 6012 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
| 6013 | &func_g.search, ¬); |
Frederic Weisbecker | f9349a8 | 2009-02-19 21:13:12 +0100 | [diff] [blame] | 6014 | |
Dmitry Safonov | 3ba0092 | 2015-09-29 19:46:14 +0300 | [diff] [blame] | 6015 | func_g.len = strlen(func_g.search); |
Frederic Weisbecker | f9349a8 | 2009-02-19 21:13:12 +0100 | [diff] [blame] | 6016 | |
Steven Rostedt | 52baf11 | 2009-02-14 01:15:39 -0500 | [diff] [blame] | 6017 | mutex_lock(&ftrace_lock); |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 6018 | |
| 6019 | if (unlikely(ftrace_disabled)) { |
| 6020 | mutex_unlock(&ftrace_lock); |
| 6021 | return -ENODEV; |
| 6022 | } |
| 6023 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 6024 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6025 | |
Steven Rostedt (Red Hat) | 546fece | 2016-11-14 16:31:49 -0500 | [diff] [blame] | 6026 | if (rec->flags & FTRACE_FL_DISABLED) |
| 6027 | continue; |
| 6028 | |
Dmitry Safonov | 0b507e1 | 2015-09-29 19:46:15 +0300 | [diff] [blame] | 6029 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 6030 | entry = ftrace_lookup_ip(hash, rec->ip); |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6031 | |
| 6032 | if (!not) { |
| 6033 | fail = 0; |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 6034 | |
| 6035 | if (entry) |
| 6036 | continue; |
| 6037 | if (add_hash_entry(hash, rec->ip) < 0) |
| 6038 | goto out; |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6039 | } else { |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 6040 | if (entry) { |
| 6041 | free_hash_entry(hash, entry); |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6042 | fail = 0; |
| 6043 | } |
| 6044 | } |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6045 | } |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 6046 | } while_for_each_ftrace_rec(); |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6047 | out: |
Steven Rostedt | 52baf11 | 2009-02-14 01:15:39 -0500 | [diff] [blame] | 6048 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6049 | |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6050 | if (fail) |
| 6051 | return -EINVAL; |
| 6052 | |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6053 | return 0; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6054 | } |
| 6055 | |
| 6056 | static ssize_t |
| 6057 | ftrace_graph_write(struct file *file, const char __user *ubuf, |
| 6058 | size_t cnt, loff_t *ppos) |
| 6059 | { |
Namhyung Kim | 6a10108 | 2013-10-14 17:24:25 +0900 | [diff] [blame] | 6060 | ssize_t read, ret = 0; |
Namhyung Kim | faf982a | 2013-10-14 17:24:24 +0900 | [diff] [blame] | 6061 | struct ftrace_graph_data *fgd = file->private_data; |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 6062 | struct trace_parser *parser; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6063 | |
Li Zefan | c7c6b1f | 2010-02-10 15:43:04 +0800 | [diff] [blame] | 6064 | if (!cnt) |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6065 | return 0; |
| 6066 | |
Steven Rostedt (VMware) | ae98d27 | 2017-02-02 16:59:06 -0500 | [diff] [blame] | 6067 | /* Read mode uses seq functions */ |
| 6068 | if (file->f_mode & FMODE_READ) { |
| 6069 | struct seq_file *m = file->private_data; |
| 6070 | fgd = m->private; |
| 6071 | } |
| 6072 | |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 6073 | parser = &fgd->parser; |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 6074 | |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 6075 | read = trace_get_user(parser, ubuf, cnt, ppos); |
jolsa@redhat.com | 689fd8b | 2009-09-11 17:29:29 +0200 | [diff] [blame] | 6076 | |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 6077 | if (read >= 0 && trace_parser_loaded(parser) && |
| 6078 | !trace_parser_cont(parser)) { |
Namhyung Kim | 6a10108 | 2013-10-14 17:24:25 +0900 | [diff] [blame] | 6079 | |
Namhyung Kim | b9b0c831 | 2017-01-20 11:44:47 +0900 | [diff] [blame] | 6080 | ret = ftrace_graph_set_hash(fgd->new_hash, |
Steven Rostedt (VMware) | e704eff | 2017-02-02 20:34:37 -0500 | [diff] [blame] | 6081 | parser->buffer); |
| 6082 | trace_parser_clear(parser); |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6083 | } |
| 6084 | |
Namhyung Kim | 6a10108 | 2013-10-14 17:24:25 +0900 | [diff] [blame] | 6085 | if (!ret) |
| 6086 | ret = read; |
Li Zefan | 1eb90f1 | 2009-09-22 13:52:57 +0800 | [diff] [blame] | 6087 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6088 | return ret; |
| 6089 | } |
| 6090 | |
| 6091 | static const struct file_operations ftrace_graph_fops = { |
Li Zefan | 8782711 | 2009-07-23 11:29:11 +0800 | [diff] [blame] | 6092 | .open = ftrace_graph_open, |
| 6093 | .read = seq_read, |
| 6094 | .write = ftrace_graph_write, |
Steven Rostedt (Red Hat) | 098c879e | 2013-12-21 17:39:40 -0500 | [diff] [blame] | 6095 | .llseek = tracing_lseek, |
Li Zefan | 8782711 | 2009-07-23 11:29:11 +0800 | [diff] [blame] | 6096 | .release = ftrace_graph_release, |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6097 | }; |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 6098 | |
| 6099 | static const struct file_operations ftrace_graph_notrace_fops = { |
| 6100 | .open = ftrace_graph_notrace_open, |
| 6101 | .read = seq_read, |
| 6102 | .write = ftrace_graph_write, |
Steven Rostedt (Red Hat) | 098c879e | 2013-12-21 17:39:40 -0500 | [diff] [blame] | 6103 | .llseek = tracing_lseek, |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 6104 | .release = ftrace_graph_release, |
| 6105 | }; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6106 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
| 6107 | |
Steven Rostedt (Red Hat) | 591dffd | 2014-01-10 16:17:45 -0500 | [diff] [blame] | 6108 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
| 6109 | struct dentry *parent) |
| 6110 | { |
| 6111 | |
| 6112 | trace_create_file("set_ftrace_filter", 0644, parent, |
| 6113 | ops, &ftrace_filter_fops); |
| 6114 | |
| 6115 | trace_create_file("set_ftrace_notrace", 0644, parent, |
| 6116 | ops, &ftrace_notrace_fops); |
| 6117 | } |
| 6118 | |
| 6119 | /* |
| 6120 | * The name "destroy_filter_files" is really a misnomer. Although |
Hariprasad Kelam | 9efb85c | 2019-03-24 00:05:23 +0530 | [diff] [blame] | 6121 | * in the future, it may actually delete the files, but this is |
Steven Rostedt (Red Hat) | 591dffd | 2014-01-10 16:17:45 -0500 | [diff] [blame] | 6122 | * really intended to make sure the ops passed in are disabled |
| 6123 | * and that when this function returns, the caller is free to |
| 6124 | * free the ops. |
| 6125 | * |
| 6126 | * The "destroy" name is only to match the "create" name that this |
| 6127 | * should be paired with. |
| 6128 | */ |
| 6129 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) |
| 6130 | { |
| 6131 | mutex_lock(&ftrace_lock); |
| 6132 | if (ops->flags & FTRACE_OPS_FL_ENABLED) |
| 6133 | ftrace_shutdown(ops, 0); |
| 6134 | ops->flags |= FTRACE_OPS_FL_DELETED; |
Steven Rostedt (VMware) | 2840f84 | 2018-12-10 23:58:01 -0500 | [diff] [blame] | 6135 | ftrace_free_filter(ops); |
Steven Rostedt (Red Hat) | 591dffd | 2014-01-10 16:17:45 -0500 | [diff] [blame] | 6136 | mutex_unlock(&ftrace_lock); |
| 6137 | } |
| 6138 | |
Steven Rostedt (Red Hat) | 8434dc9 | 2015-01-20 12:13:40 -0500 | [diff] [blame] | 6139 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 6140 | { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 6141 | |
Frederic Weisbecker | 5452af6 | 2009-03-27 00:25:38 +0100 | [diff] [blame] | 6142 | trace_create_file("available_filter_functions", 0444, |
| 6143 | d_tracer, NULL, &ftrace_avail_fops); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 6144 | |
Steven Rostedt | 647bcd0 | 2011-05-03 14:39:21 -0400 | [diff] [blame] | 6145 | trace_create_file("enabled_functions", 0444, |
| 6146 | d_tracer, NULL, &ftrace_enabled_fops); |
| 6147 | |
Steven Rostedt (Red Hat) | 591dffd | 2014-01-10 16:17:45 -0500 | [diff] [blame] | 6148 | ftrace_create_filter_files(&global_ops, d_tracer); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 6149 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6150 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Chen LinX | 1ce0500 | 2014-09-03 14:31:09 +0800 | [diff] [blame] | 6151 | trace_create_file("set_graph_function", 0644, d_tracer, |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6152 | NULL, |
| 6153 | &ftrace_graph_fops); |
Chen LinX | 1ce0500 | 2014-09-03 14:31:09 +0800 | [diff] [blame] | 6154 | trace_create_file("set_graph_notrace", 0644, d_tracer, |
Namhyung Kim | 29ad23b | 2013-10-14 17:24:26 +0900 | [diff] [blame] | 6155 | NULL, |
| 6156 | &ftrace_graph_notrace_fops); |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 6157 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
| 6158 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 6159 | return 0; |
| 6160 | } |
| 6161 | |
Steven Rostedt | 9fd4932 | 2012-04-24 22:32:06 -0400 | [diff] [blame] | 6162 | static int ftrace_cmp_ips(const void *a, const void *b) |
Steven Rostedt | 6895061 | 2011-12-16 17:06:45 -0500 | [diff] [blame] | 6163 | { |
Steven Rostedt | 9fd4932 | 2012-04-24 22:32:06 -0400 | [diff] [blame] | 6164 | const unsigned long *ipa = a; |
| 6165 | const unsigned long *ipb = b; |
Steven Rostedt | 6895061 | 2011-12-16 17:06:45 -0500 | [diff] [blame] | 6166 | |
Steven Rostedt | 9fd4932 | 2012-04-24 22:32:06 -0400 | [diff] [blame] | 6167 | if (*ipa > *ipb) |
| 6168 | return 1; |
| 6169 | if (*ipa < *ipb) |
| 6170 | return -1; |
| 6171 | return 0; |
| 6172 | } |
| 6173 | |
Jiri Olsa | 5cb084b | 2009-10-13 16:33:53 -0400 | [diff] [blame] | 6174 | static int ftrace_process_locs(struct module *mod, |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 6175 | unsigned long *start, |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6176 | unsigned long *end) |
| 6177 | { |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6178 | struct ftrace_page *start_pg; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6179 | struct ftrace_page *pg; |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6180 | struct dyn_ftrace *rec; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6181 | unsigned long count; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6182 | unsigned long *p; |
| 6183 | unsigned long addr; |
Steven Rostedt | 4376cac | 2011-06-24 23:28:13 -0400 | [diff] [blame] | 6184 | unsigned long flags = 0; /* Shut up gcc */ |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6185 | int ret = -ENOMEM; |
| 6186 | |
| 6187 | count = end - start; |
| 6188 | |
| 6189 | if (!count) |
| 6190 | return 0; |
| 6191 | |
Steven Rostedt | 9fd4932 | 2012-04-24 22:32:06 -0400 | [diff] [blame] | 6192 | sort(start, count, sizeof(*start), |
Rasmus Villemoes | 6db0290 | 2015-09-09 23:27:02 +0200 | [diff] [blame] | 6193 | ftrace_cmp_ips, NULL); |
Steven Rostedt | 9fd4932 | 2012-04-24 22:32:06 -0400 | [diff] [blame] | 6194 | |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6195 | start_pg = ftrace_allocate_pages(count); |
| 6196 | if (!start_pg) |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6197 | return -ENOMEM; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6198 | |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 6199 | mutex_lock(&ftrace_lock); |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6200 | |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6201 | /* |
| 6202 | * Core and each module needs their own pages, as |
| 6203 | * modules will free them when they are removed. |
| 6204 | * Force a new page to be allocated for modules. |
| 6205 | */ |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6206 | if (!mod) { |
| 6207 | WARN_ON(ftrace_pages || ftrace_pages_start); |
| 6208 | /* First initialization */ |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6209 | ftrace_pages = ftrace_pages_start = start_pg; |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6210 | } else { |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6211 | if (!ftrace_pages) |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6212 | goto out; |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6213 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6214 | if (WARN_ON(ftrace_pages->next)) { |
| 6215 | /* Hmm, we have free pages? */ |
| 6216 | while (ftrace_pages->next) |
| 6217 | ftrace_pages = ftrace_pages->next; |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6218 | } |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6219 | |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6220 | ftrace_pages->next = start_pg; |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6221 | } |
| 6222 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6223 | p = start; |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6224 | pg = start_pg; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6225 | while (p < end) { |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 6226 | unsigned long end_offset; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6227 | addr = ftrace_call_adjust(*p++); |
Steven Rostedt | 20e5227 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 6228 | /* |
| 6229 | * Some architecture linkers will pad between |
| 6230 | * the different mcount_loc sections of different |
| 6231 | * object files to satisfy alignments. |
| 6232 | * Skip any NULL pointers. |
| 6233 | */ |
| 6234 | if (!addr) |
| 6235 | continue; |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6236 | |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 6237 | end_offset = (pg->index+1) * sizeof(pg->records[0]); |
| 6238 | if (end_offset > PAGE_SIZE << pg->order) { |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6239 | /* We should have allocated enough */ |
| 6240 | if (WARN_ON(!pg->next)) |
| 6241 | break; |
| 6242 | pg = pg->next; |
| 6243 | } |
| 6244 | |
| 6245 | rec = &pg->records[pg->index++]; |
| 6246 | rec->ip = addr; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6247 | } |
| 6248 | |
Steven Rostedt | 706c81f | 2012-04-24 23:45:26 -0400 | [diff] [blame] | 6249 | /* We should have used all pages */ |
| 6250 | WARN_ON(pg->next); |
| 6251 | |
| 6252 | /* Assign the last page to ftrace_pages */ |
| 6253 | ftrace_pages = pg; |
| 6254 | |
Steven Rostedt | a4f18ed | 2011-06-07 09:26:46 -0400 | [diff] [blame] | 6255 | /* |
Steven Rostedt | 4376cac | 2011-06-24 23:28:13 -0400 | [diff] [blame] | 6256 | * We only need to disable interrupts on start up |
| 6257 | * because we are modifying code that an interrupt |
| 6258 | * may execute, and the modification is not atomic. |
| 6259 | * But for modules, nothing runs the code we modify |
| 6260 | * until we are finished with it, and there's no |
| 6261 | * reason to cause large interrupt latencies while we do it. |
Steven Rostedt | a4f18ed | 2011-06-07 09:26:46 -0400 | [diff] [blame] | 6262 | */ |
Steven Rostedt | 4376cac | 2011-06-24 23:28:13 -0400 | [diff] [blame] | 6263 | if (!mod) |
| 6264 | local_irq_save(flags); |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 6265 | ftrace_update_code(mod, start_pg); |
Steven Rostedt | 4376cac | 2011-06-24 23:28:13 -0400 | [diff] [blame] | 6266 | if (!mod) |
| 6267 | local_irq_restore(flags); |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6268 | ret = 0; |
| 6269 | out: |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 6270 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6271 | |
Steven Rostedt | a790087 | 2011-12-16 16:23:44 -0500 | [diff] [blame] | 6272 | return ret; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6273 | } |
| 6274 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6275 | struct ftrace_mod_func { |
| 6276 | struct list_head list; |
| 6277 | char *name; |
| 6278 | unsigned long ip; |
| 6279 | unsigned int size; |
| 6280 | }; |
| 6281 | |
| 6282 | struct ftrace_mod_map { |
Steven Rostedt (VMware) | 6aa6978 | 2017-09-05 19:20:16 -0400 | [diff] [blame] | 6283 | struct rcu_head rcu; |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6284 | struct list_head list; |
| 6285 | struct module *mod; |
| 6286 | unsigned long start_addr; |
| 6287 | unsigned long end_addr; |
| 6288 | struct list_head funcs; |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6289 | unsigned int num_funcs; |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6290 | }; |
| 6291 | |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6292 | static int ftrace_get_trampoline_kallsym(unsigned int symnum, |
| 6293 | unsigned long *value, char *type, |
| 6294 | char *name, char *module_name, |
| 6295 | int *exported) |
| 6296 | { |
| 6297 | struct ftrace_ops *op; |
| 6298 | |
| 6299 | list_for_each_entry_rcu(op, &ftrace_ops_trampoline_list, list) { |
| 6300 | if (!op->trampoline || symnum--) |
| 6301 | continue; |
| 6302 | *value = op->trampoline; |
| 6303 | *type = 't'; |
| 6304 | strlcpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN); |
| 6305 | strlcpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN); |
| 6306 | *exported = 0; |
| 6307 | return 0; |
| 6308 | } |
| 6309 | |
| 6310 | return -ERANGE; |
| 6311 | } |
| 6312 | |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6313 | #ifdef CONFIG_MODULES |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6314 | |
| 6315 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) |
| 6316 | |
Steven Rostedt (VMware) | 6aa6978 | 2017-09-05 19:20:16 -0400 | [diff] [blame] | 6317 | static LIST_HEAD(ftrace_mod_maps); |
| 6318 | |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6319 | static int referenced_filters(struct dyn_ftrace *rec) |
| 6320 | { |
| 6321 | struct ftrace_ops *ops; |
| 6322 | int cnt = 0; |
| 6323 | |
| 6324 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { |
Chengming Zhou | 8a224ff | 2020-07-29 02:05:53 +0800 | [diff] [blame] | 6325 | if (ops_references_rec(ops, rec)) { |
Chengming Zhou | c5f5157 | 2020-07-29 02:05:54 +0800 | [diff] [blame] | 6326 | if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_DIRECT)) |
| 6327 | continue; |
| 6328 | if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_IPMODIFY)) |
| 6329 | continue; |
Chengming Zhou | 8a224ff | 2020-07-29 02:05:53 +0800 | [diff] [blame] | 6330 | cnt++; |
| 6331 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) |
| 6332 | rec->flags |= FTRACE_FL_REGS; |
Chengming Zhou | c5f5157 | 2020-07-29 02:05:54 +0800 | [diff] [blame] | 6333 | if (cnt == 1 && ops->trampoline) |
| 6334 | rec->flags |= FTRACE_FL_TRAMP; |
| 6335 | else |
| 6336 | rec->flags &= ~FTRACE_FL_TRAMP; |
Chengming Zhou | 8a224ff | 2020-07-29 02:05:53 +0800 | [diff] [blame] | 6337 | } |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6338 | } |
| 6339 | |
| 6340 | return cnt; |
| 6341 | } |
| 6342 | |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6343 | static void |
| 6344 | clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash) |
| 6345 | { |
| 6346 | struct ftrace_func_entry *entry; |
| 6347 | struct dyn_ftrace *rec; |
| 6348 | int i; |
| 6349 | |
| 6350 | if (ftrace_hash_empty(hash)) |
| 6351 | return; |
| 6352 | |
| 6353 | for (i = 0; i < pg->index; i++) { |
| 6354 | rec = &pg->records[i]; |
| 6355 | entry = __ftrace_lookup_ip(hash, rec->ip); |
| 6356 | /* |
| 6357 | * Do not allow this rec to match again. |
| 6358 | * Yeah, it may waste some memory, but will be removed |
| 6359 | * if/when the hash is modified again. |
| 6360 | */ |
| 6361 | if (entry) |
| 6362 | entry->ip = 0; |
| 6363 | } |
| 6364 | } |
| 6365 | |
Ingo Molnar | f2cc020 | 2021-03-23 18:49:35 +0100 | [diff] [blame] | 6366 | /* Clear any records from hashes */ |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6367 | static void clear_mod_from_hashes(struct ftrace_page *pg) |
| 6368 | { |
| 6369 | struct trace_array *tr; |
| 6370 | |
| 6371 | mutex_lock(&trace_types_lock); |
| 6372 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
| 6373 | if (!tr->ops || !tr->ops->func_hash) |
| 6374 | continue; |
| 6375 | mutex_lock(&tr->ops->func_hash->regex_lock); |
| 6376 | clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash); |
| 6377 | clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash); |
| 6378 | mutex_unlock(&tr->ops->func_hash->regex_lock); |
| 6379 | } |
| 6380 | mutex_unlock(&trace_types_lock); |
| 6381 | } |
| 6382 | |
Steven Rostedt (VMware) | 6aa6978 | 2017-09-05 19:20:16 -0400 | [diff] [blame] | 6383 | static void ftrace_free_mod_map(struct rcu_head *rcu) |
| 6384 | { |
| 6385 | struct ftrace_mod_map *mod_map = container_of(rcu, struct ftrace_mod_map, rcu); |
| 6386 | struct ftrace_mod_func *mod_func; |
| 6387 | struct ftrace_mod_func *n; |
| 6388 | |
| 6389 | /* All the contents of mod_map are now not visible to readers */ |
| 6390 | list_for_each_entry_safe(mod_func, n, &mod_map->funcs, list) { |
| 6391 | kfree(mod_func->name); |
| 6392 | list_del(&mod_func->list); |
| 6393 | kfree(mod_func); |
| 6394 | } |
| 6395 | |
| 6396 | kfree(mod_map); |
| 6397 | } |
| 6398 | |
jolsa@redhat.com | e7247a1 | 2009-10-07 19:00:35 +0200 | [diff] [blame] | 6399 | void ftrace_release_mod(struct module *mod) |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6400 | { |
Steven Rostedt (VMware) | 6aa6978 | 2017-09-05 19:20:16 -0400 | [diff] [blame] | 6401 | struct ftrace_mod_map *mod_map; |
| 6402 | struct ftrace_mod_map *n; |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6403 | struct dyn_ftrace *rec; |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6404 | struct ftrace_page **last_pg; |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6405 | struct ftrace_page *tmp_page = NULL; |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6406 | struct ftrace_page *pg; |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6407 | |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6408 | mutex_lock(&ftrace_lock); |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 6409 | |
| 6410 | if (ftrace_disabled) |
| 6411 | goto out_unlock; |
| 6412 | |
Steven Rostedt (VMware) | 6aa6978 | 2017-09-05 19:20:16 -0400 | [diff] [blame] | 6413 | list_for_each_entry_safe(mod_map, n, &ftrace_mod_maps, list) { |
| 6414 | if (mod_map->mod == mod) { |
| 6415 | list_del_rcu(&mod_map->list); |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 6416 | call_rcu(&mod_map->rcu, ftrace_free_mod_map); |
Steven Rostedt (VMware) | 6aa6978 | 2017-09-05 19:20:16 -0400 | [diff] [blame] | 6417 | break; |
| 6418 | } |
| 6419 | } |
| 6420 | |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6421 | /* |
| 6422 | * Each module has its own ftrace_pages, remove |
| 6423 | * them from the list. |
| 6424 | */ |
| 6425 | last_pg = &ftrace_pages_start; |
| 6426 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { |
| 6427 | rec = &pg->records[0]; |
Steven Rostedt (VMware) | 3e23428 | 2017-03-03 18:00:22 -0500 | [diff] [blame] | 6428 | if (within_module_core(rec->ip, mod) || |
| 6429 | within_module_init(rec->ip, mod)) { |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6430 | /* |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6431 | * As core pages are first, the first |
| 6432 | * page should never be a module page. |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6433 | */ |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6434 | if (WARN_ON(pg == ftrace_pages_start)) |
| 6435 | goto out_unlock; |
| 6436 | |
| 6437 | /* Check if we are deleting the last page */ |
| 6438 | if (pg == ftrace_pages) |
| 6439 | ftrace_pages = next_to_ftrace_page(last_pg); |
| 6440 | |
Steven Rostedt (VMware) | 83dd149 | 2017-06-27 11:04:40 -0400 | [diff] [blame] | 6441 | ftrace_update_tot_cnt -= pg->index; |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6442 | *last_pg = pg->next; |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6443 | |
| 6444 | pg->next = tmp_page; |
| 6445 | tmp_page = pg; |
Steven Rostedt | 32082309 | 2011-12-16 14:42:37 -0500 | [diff] [blame] | 6446 | } else |
| 6447 | last_pg = &pg->next; |
| 6448 | } |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 6449 | out_unlock: |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6450 | mutex_unlock(&ftrace_lock); |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6451 | |
| 6452 | for (pg = tmp_page; pg; pg = tmp_page) { |
| 6453 | |
| 6454 | /* Needs to be called outside of ftrace_lock */ |
| 6455 | clear_mod_from_hashes(pg); |
| 6456 | |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 6457 | if (pg->records) { |
| 6458 | free_pages((unsigned long)pg->records, pg->order); |
| 6459 | ftrace_number_of_pages -= 1 << pg->order; |
| 6460 | } |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6461 | tmp_page = pg->next; |
| 6462 | kfree(pg); |
Steven Rostedt (VMware) | da537f0 | 2019-10-01 14:38:07 -0400 | [diff] [blame] | 6463 | ftrace_number_of_groups--; |
Steven Rostedt (VMware) | 2a5bfe4 | 2017-08-31 17:36:51 -0400 | [diff] [blame] | 6464 | } |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6465 | } |
| 6466 | |
Jessica Yu | 7dcd182 | 2016-02-16 17:32:33 -0500 | [diff] [blame] | 6467 | void ftrace_module_enable(struct module *mod) |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6468 | { |
| 6469 | struct dyn_ftrace *rec; |
| 6470 | struct ftrace_page *pg; |
| 6471 | |
| 6472 | mutex_lock(&ftrace_lock); |
| 6473 | |
| 6474 | if (ftrace_disabled) |
| 6475 | goto out_unlock; |
| 6476 | |
| 6477 | /* |
| 6478 | * If the tracing is enabled, go ahead and enable the record. |
| 6479 | * |
Hariprasad Kelam | 9efb85c | 2019-03-24 00:05:23 +0530 | [diff] [blame] | 6480 | * The reason not to enable the record immediately is the |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6481 | * inherent check of ftrace_make_nop/ftrace_make_call for |
| 6482 | * correct previous instructions. Making first the NOP |
| 6483 | * conversion puts the module to the correct state, thus |
| 6484 | * passing the ftrace_make_call check. |
| 6485 | * |
| 6486 | * We also delay this to after the module code already set the |
| 6487 | * text to read-only, as we now need to set it back to read-write |
| 6488 | * so that we can modify the text. |
| 6489 | */ |
| 6490 | if (ftrace_start_up) |
| 6491 | ftrace_arch_code_modify_prepare(); |
| 6492 | |
| 6493 | do_for_each_ftrace_rec(pg, rec) { |
| 6494 | int cnt; |
| 6495 | /* |
| 6496 | * do_for_each_ftrace_rec() is a double loop. |
| 6497 | * module text shares the pg. If a record is |
| 6498 | * not part of this module, then skip this pg, |
| 6499 | * which the "break" will do. |
| 6500 | */ |
Steven Rostedt (VMware) | 3e23428 | 2017-03-03 18:00:22 -0500 | [diff] [blame] | 6501 | if (!within_module_core(rec->ip, mod) && |
| 6502 | !within_module_init(rec->ip, mod)) |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6503 | break; |
| 6504 | |
| 6505 | cnt = 0; |
| 6506 | |
| 6507 | /* |
| 6508 | * When adding a module, we need to check if tracers are |
| 6509 | * currently enabled and if they are, and can trace this record, |
| 6510 | * we need to enable the module functions as well as update the |
| 6511 | * reference counts for those function records. |
| 6512 | */ |
| 6513 | if (ftrace_start_up) |
| 6514 | cnt += referenced_filters(rec); |
| 6515 | |
Chengming Zhou | 8a224ff | 2020-07-29 02:05:53 +0800 | [diff] [blame] | 6516 | rec->flags &= ~FTRACE_FL_DISABLED; |
| 6517 | rec->flags += cnt; |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6518 | |
| 6519 | if (ftrace_start_up && cnt) { |
| 6520 | int failed = __ftrace_replace_code(rec, 1); |
| 6521 | if (failed) { |
| 6522 | ftrace_bug(failed, rec); |
| 6523 | goto out_loop; |
| 6524 | } |
| 6525 | } |
| 6526 | |
| 6527 | } while_for_each_ftrace_rec(); |
| 6528 | |
| 6529 | out_loop: |
| 6530 | if (ftrace_start_up) |
| 6531 | ftrace_arch_code_modify_post_process(); |
| 6532 | |
| 6533 | out_unlock: |
| 6534 | mutex_unlock(&ftrace_lock); |
Steven Rostedt (VMware) | d7fbf8df | 2017-06-26 10:57:21 -0400 | [diff] [blame] | 6535 | |
| 6536 | process_cached_mods(mod->name); |
Steven Rostedt (Red Hat) | b7ffffb | 2016-01-07 15:40:01 -0500 | [diff] [blame] | 6537 | } |
| 6538 | |
Steven Rostedt (Red Hat) | a949ae5 | 2014-04-24 10:40:12 -0400 | [diff] [blame] | 6539 | void ftrace_module_init(struct module *mod) |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6540 | { |
Steven Rostedt (Red Hat) | 97e9b4f | 2015-12-23 12:12:22 -0500 | [diff] [blame] | 6541 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
Abel Vesa | b6b71f6 | 2015-12-02 15:39:57 +0100 | [diff] [blame] | 6542 | return; |
| 6543 | |
Steven Rostedt (Red Hat) | 97e9b4f | 2015-12-23 12:12:22 -0500 | [diff] [blame] | 6544 | ftrace_process_locs(mod, mod->ftrace_callsites, |
| 6545 | mod->ftrace_callsites + mod->num_ftrace_callsites); |
Steven Rostedt (Red Hat) | 8c189ea | 2013-02-13 15:18:38 -0500 | [diff] [blame] | 6546 | } |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6547 | |
| 6548 | static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, |
| 6549 | struct dyn_ftrace *rec) |
| 6550 | { |
| 6551 | struct ftrace_mod_func *mod_func; |
| 6552 | unsigned long symsize; |
| 6553 | unsigned long offset; |
| 6554 | char str[KSYM_SYMBOL_LEN]; |
| 6555 | char *modname; |
| 6556 | const char *ret; |
| 6557 | |
| 6558 | ret = kallsyms_lookup(rec->ip, &symsize, &offset, &modname, str); |
| 6559 | if (!ret) |
| 6560 | return; |
| 6561 | |
| 6562 | mod_func = kmalloc(sizeof(*mod_func), GFP_KERNEL); |
| 6563 | if (!mod_func) |
| 6564 | return; |
| 6565 | |
| 6566 | mod_func->name = kstrdup(str, GFP_KERNEL); |
| 6567 | if (!mod_func->name) { |
| 6568 | kfree(mod_func); |
| 6569 | return; |
| 6570 | } |
| 6571 | |
| 6572 | mod_func->ip = rec->ip - offset; |
| 6573 | mod_func->size = symsize; |
| 6574 | |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6575 | mod_map->num_funcs++; |
| 6576 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6577 | list_add_rcu(&mod_func->list, &mod_map->funcs); |
| 6578 | } |
| 6579 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6580 | static struct ftrace_mod_map * |
| 6581 | allocate_ftrace_mod_map(struct module *mod, |
| 6582 | unsigned long start, unsigned long end) |
| 6583 | { |
| 6584 | struct ftrace_mod_map *mod_map; |
| 6585 | |
| 6586 | mod_map = kmalloc(sizeof(*mod_map), GFP_KERNEL); |
| 6587 | if (!mod_map) |
| 6588 | return NULL; |
| 6589 | |
| 6590 | mod_map->mod = mod; |
| 6591 | mod_map->start_addr = start; |
| 6592 | mod_map->end_addr = end; |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6593 | mod_map->num_funcs = 0; |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6594 | |
| 6595 | INIT_LIST_HEAD_RCU(&mod_map->funcs); |
| 6596 | |
| 6597 | list_add_rcu(&mod_map->list, &ftrace_mod_maps); |
| 6598 | |
| 6599 | return mod_map; |
| 6600 | } |
| 6601 | |
| 6602 | static const char * |
| 6603 | ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, |
| 6604 | unsigned long addr, unsigned long *size, |
| 6605 | unsigned long *off, char *sym) |
| 6606 | { |
| 6607 | struct ftrace_mod_func *found_func = NULL; |
| 6608 | struct ftrace_mod_func *mod_func; |
| 6609 | |
| 6610 | list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { |
| 6611 | if (addr >= mod_func->ip && |
| 6612 | addr < mod_func->ip + mod_func->size) { |
| 6613 | found_func = mod_func; |
| 6614 | break; |
| 6615 | } |
| 6616 | } |
| 6617 | |
| 6618 | if (found_func) { |
| 6619 | if (size) |
| 6620 | *size = found_func->size; |
| 6621 | if (off) |
| 6622 | *off = addr - found_func->ip; |
| 6623 | if (sym) |
| 6624 | strlcpy(sym, found_func->name, KSYM_NAME_LEN); |
| 6625 | |
| 6626 | return found_func->name; |
| 6627 | } |
| 6628 | |
| 6629 | return NULL; |
| 6630 | } |
| 6631 | |
| 6632 | const char * |
| 6633 | ftrace_mod_address_lookup(unsigned long addr, unsigned long *size, |
| 6634 | unsigned long *off, char **modname, char *sym) |
| 6635 | { |
| 6636 | struct ftrace_mod_map *mod_map; |
| 6637 | const char *ret = NULL; |
| 6638 | |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 6639 | /* mod_map is freed via call_rcu() */ |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6640 | preempt_disable(); |
| 6641 | list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { |
| 6642 | ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym); |
| 6643 | if (ret) { |
| 6644 | if (modname) |
| 6645 | *modname = mod_map->mod->name; |
| 6646 | break; |
| 6647 | } |
| 6648 | } |
| 6649 | preempt_enable(); |
| 6650 | |
| 6651 | return ret; |
| 6652 | } |
| 6653 | |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6654 | int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value, |
| 6655 | char *type, char *name, |
| 6656 | char *module_name, int *exported) |
| 6657 | { |
| 6658 | struct ftrace_mod_map *mod_map; |
| 6659 | struct ftrace_mod_func *mod_func; |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6660 | int ret; |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6661 | |
| 6662 | preempt_disable(); |
| 6663 | list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { |
| 6664 | |
| 6665 | if (symnum >= mod_map->num_funcs) { |
| 6666 | symnum -= mod_map->num_funcs; |
| 6667 | continue; |
| 6668 | } |
| 6669 | |
| 6670 | list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { |
| 6671 | if (symnum > 1) { |
| 6672 | symnum--; |
| 6673 | continue; |
| 6674 | } |
| 6675 | |
| 6676 | *value = mod_func->ip; |
| 6677 | *type = 'T'; |
| 6678 | strlcpy(name, mod_func->name, KSYM_NAME_LEN); |
| 6679 | strlcpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); |
| 6680 | *exported = 1; |
| 6681 | preempt_enable(); |
| 6682 | return 0; |
| 6683 | } |
| 6684 | WARN_ON(1); |
| 6685 | break; |
| 6686 | } |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6687 | ret = ftrace_get_trampoline_kallsym(symnum, value, type, name, |
| 6688 | module_name, exported); |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6689 | preempt_enable(); |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6690 | return ret; |
Steven Rostedt (VMware) | 6171a03 | 2017-09-06 08:40:41 -0400 | [diff] [blame] | 6691 | } |
| 6692 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6693 | #else |
| 6694 | static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, |
| 6695 | struct dyn_ftrace *rec) { } |
| 6696 | static inline struct ftrace_mod_map * |
| 6697 | allocate_ftrace_mod_map(struct module *mod, |
| 6698 | unsigned long start, unsigned long end) |
| 6699 | { |
| 6700 | return NULL; |
| 6701 | } |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6702 | int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value, |
| 6703 | char *type, char *name, char *module_name, |
| 6704 | int *exported) |
| 6705 | { |
| 6706 | int ret; |
| 6707 | |
| 6708 | preempt_disable(); |
| 6709 | ret = ftrace_get_trampoline_kallsym(symnum, value, type, name, |
| 6710 | module_name, exported); |
| 6711 | preempt_enable(); |
| 6712 | return ret; |
| 6713 | } |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6714 | #endif /* CONFIG_MODULES */ |
| 6715 | |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6716 | struct ftrace_init_func { |
| 6717 | struct list_head list; |
| 6718 | unsigned long ip; |
| 6719 | }; |
| 6720 | |
| 6721 | /* Clear any init ips from hashes */ |
| 6722 | static void |
| 6723 | clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash) |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6724 | { |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6725 | struct ftrace_func_entry *entry; |
| 6726 | |
Changbin Du | 0846875 | 2019-09-10 22:33:36 +0800 | [diff] [blame] | 6727 | entry = ftrace_lookup_ip(hash, func->ip); |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6728 | /* |
| 6729 | * Do not allow this rec to match again. |
| 6730 | * Yeah, it may waste some memory, but will be removed |
| 6731 | * if/when the hash is modified again. |
| 6732 | */ |
| 6733 | if (entry) |
| 6734 | entry->ip = 0; |
| 6735 | } |
| 6736 | |
| 6737 | static void |
| 6738 | clear_func_from_hashes(struct ftrace_init_func *func) |
| 6739 | { |
| 6740 | struct trace_array *tr; |
| 6741 | |
| 6742 | mutex_lock(&trace_types_lock); |
| 6743 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
| 6744 | if (!tr->ops || !tr->ops->func_hash) |
| 6745 | continue; |
| 6746 | mutex_lock(&tr->ops->func_hash->regex_lock); |
| 6747 | clear_func_from_hash(func, tr->ops->func_hash->filter_hash); |
| 6748 | clear_func_from_hash(func, tr->ops->func_hash->notrace_hash); |
| 6749 | mutex_unlock(&tr->ops->func_hash->regex_lock); |
| 6750 | } |
| 6751 | mutex_unlock(&trace_types_lock); |
| 6752 | } |
| 6753 | |
| 6754 | static void add_to_clear_hash_list(struct list_head *clear_list, |
| 6755 | struct dyn_ftrace *rec) |
| 6756 | { |
| 6757 | struct ftrace_init_func *func; |
| 6758 | |
| 6759 | func = kmalloc(sizeof(*func), GFP_KERNEL); |
| 6760 | if (!func) { |
Steven Rostedt (VMware) | 24589e3 | 2020-01-25 10:52:30 -0500 | [diff] [blame] | 6761 | MEM_FAIL(1, "alloc failure, ftrace filter could be stale\n"); |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6762 | return; |
| 6763 | } |
| 6764 | |
| 6765 | func->ip = rec->ip; |
| 6766 | list_add(&func->list, clear_list); |
| 6767 | } |
| 6768 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6769 | void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6770 | { |
Steven Rostedt (VMware) | 6cafbe1 | 2017-06-20 10:44:58 -0400 | [diff] [blame] | 6771 | unsigned long start = (unsigned long)(start_ptr); |
| 6772 | unsigned long end = (unsigned long)(end_ptr); |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6773 | struct ftrace_page **last_pg = &ftrace_pages_start; |
| 6774 | struct ftrace_page *pg; |
| 6775 | struct dyn_ftrace *rec; |
| 6776 | struct dyn_ftrace key; |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6777 | struct ftrace_mod_map *mod_map = NULL; |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6778 | struct ftrace_init_func *func, *func_next; |
| 6779 | struct list_head clear_hash; |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6780 | |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6781 | INIT_LIST_HEAD(&clear_hash); |
| 6782 | |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6783 | key.ip = start; |
| 6784 | key.flags = end; /* overload flags, as it is unsigned long */ |
| 6785 | |
| 6786 | mutex_lock(&ftrace_lock); |
| 6787 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6788 | /* |
| 6789 | * If we are freeing module init memory, then check if |
| 6790 | * any tracer is active. If so, we need to save a mapping of |
| 6791 | * the module functions being freed with the address. |
| 6792 | */ |
| 6793 | if (mod && ftrace_ops_list != &ftrace_list_end) |
| 6794 | mod_map = allocate_ftrace_mod_map(mod, start, end); |
| 6795 | |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6796 | for (pg = ftrace_pages_start; pg; last_pg = &pg->next, pg = *last_pg) { |
| 6797 | if (end < pg->records[0].ip || |
| 6798 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) |
| 6799 | continue; |
| 6800 | again: |
| 6801 | rec = bsearch(&key, pg->records, pg->index, |
| 6802 | sizeof(struct dyn_ftrace), |
| 6803 | ftrace_cmp_recs); |
| 6804 | if (!rec) |
| 6805 | continue; |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6806 | |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6807 | /* rec will be cleared from hashes after ftrace_lock unlock */ |
| 6808 | add_to_clear_hash_list(&clear_hash, rec); |
| 6809 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6810 | if (mod_map) |
| 6811 | save_ftrace_mod_rec(mod_map, rec); |
| 6812 | |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6813 | pg->index--; |
Steven Rostedt (VMware) | 4ec7846 | 2017-06-28 11:57:03 -0400 | [diff] [blame] | 6814 | ftrace_update_tot_cnt--; |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6815 | if (!pg->index) { |
| 6816 | *last_pg = pg->next; |
Linus Torvalds | db42523 | 2021-04-01 16:14:17 -0400 | [diff] [blame] | 6817 | if (pg->records) { |
| 6818 | free_pages((unsigned long)pg->records, pg->order); |
| 6819 | ftrace_number_of_pages -= 1 << pg->order; |
| 6820 | } |
Steven Rostedt (VMware) | da537f0 | 2019-10-01 14:38:07 -0400 | [diff] [blame] | 6821 | ftrace_number_of_groups--; |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6822 | kfree(pg); |
| 6823 | pg = container_of(last_pg, struct ftrace_page, next); |
| 6824 | if (!(*last_pg)) |
| 6825 | ftrace_pages = pg; |
| 6826 | continue; |
| 6827 | } |
| 6828 | memmove(rec, rec + 1, |
| 6829 | (pg->index - (rec - pg->records)) * sizeof(*rec)); |
| 6830 | /* More than one function may be in this block */ |
| 6831 | goto again; |
| 6832 | } |
| 6833 | mutex_unlock(&ftrace_lock); |
Joel Fernandes | 8715b10 | 2017-10-09 12:29:31 -0700 | [diff] [blame] | 6834 | |
| 6835 | list_for_each_entry_safe(func, func_next, &clear_hash, list) { |
| 6836 | clear_func_from_hashes(func); |
| 6837 | kfree(func); |
| 6838 | } |
Steven Rostedt (VMware) | 42c269c | 2017-03-03 16:15:39 -0500 | [diff] [blame] | 6839 | } |
| 6840 | |
Steven Rostedt (VMware) | 6cafbe1 | 2017-06-20 10:44:58 -0400 | [diff] [blame] | 6841 | void __init ftrace_free_init_mem(void) |
| 6842 | { |
| 6843 | void *start = (void *)(&__init_begin); |
| 6844 | void *end = (void *)(&__init_end); |
| 6845 | |
Steven Rostedt (VMware) | aba4b5c | 2017-09-01 08:35:38 -0400 | [diff] [blame] | 6846 | ftrace_free_mem(NULL, start, end); |
Steven Rostedt | 93eb677 | 2009-04-15 13:24:06 -0400 | [diff] [blame] | 6847 | } |
| 6848 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6849 | void __init ftrace_init(void) |
| 6850 | { |
Jiri Slaby | 1dc43cf | 2014-02-24 19:59:56 +0100 | [diff] [blame] | 6851 | extern unsigned long __start_mcount_loc[]; |
| 6852 | extern unsigned long __stop_mcount_loc[]; |
Jiri Slaby | 3a36cb1 | 2014-02-24 19:59:59 +0100 | [diff] [blame] | 6853 | unsigned long count, flags; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6854 | int ret; |
| 6855 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6856 | local_irq_save(flags); |
Jiri Slaby | 3a36cb1 | 2014-02-24 19:59:59 +0100 | [diff] [blame] | 6857 | ret = ftrace_dyn_arch_init(); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6858 | local_irq_restore(flags); |
Jiri Slaby | af64a7c | 2014-02-24 19:59:58 +0100 | [diff] [blame] | 6859 | if (ret) |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6860 | goto failed; |
| 6861 | |
| 6862 | count = __stop_mcount_loc - __start_mcount_loc; |
Jiri Slaby | c867ccd | 2014-02-24 19:59:57 +0100 | [diff] [blame] | 6863 | if (!count) { |
| 6864 | pr_info("ftrace: No functions to be traced?\n"); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6865 | goto failed; |
Jiri Slaby | c867ccd | 2014-02-24 19:59:57 +0100 | [diff] [blame] | 6866 | } |
| 6867 | |
| 6868 | pr_info("ftrace: allocating %ld entries in %ld pages\n", |
| 6869 | count, count / ENTRIES_PER_PAGE + 1); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6870 | |
| 6871 | last_ftrace_enabled = ftrace_enabled = 1; |
| 6872 | |
Jiri Olsa | 5cb084b | 2009-10-13 16:33:53 -0400 | [diff] [blame] | 6873 | ret = ftrace_process_locs(NULL, |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 6874 | __start_mcount_loc, |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6875 | __stop_mcount_loc); |
| 6876 | |
Steven Rostedt (VMware) | da537f0 | 2019-10-01 14:38:07 -0400 | [diff] [blame] | 6877 | pr_info("ftrace: allocated %ld pages with %ld groups\n", |
| 6878 | ftrace_number_of_pages, ftrace_number_of_groups); |
| 6879 | |
Steven Rostedt | 2af15d6 | 2009-05-28 13:37:24 -0400 | [diff] [blame] | 6880 | set_ftrace_early_filters(); |
| 6881 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6882 | return; |
| 6883 | failed: |
| 6884 | ftrace_disabled = 1; |
| 6885 | } |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 6886 | |
Steven Rostedt (Red Hat) | f3bea49 | 2014-07-02 23:23:31 -0400 | [diff] [blame] | 6887 | /* Do nothing if arch does not support this */ |
| 6888 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) |
| 6889 | { |
| 6890 | } |
| 6891 | |
| 6892 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
| 6893 | { |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6894 | unsigned long trampoline = ops->trampoline; |
| 6895 | |
Steven Rostedt (Red Hat) | f3bea49 | 2014-07-02 23:23:31 -0400 | [diff] [blame] | 6896 | arch_ftrace_update_trampoline(ops); |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6897 | if (ops->trampoline && ops->trampoline != trampoline && |
Adrian Hunter | dd9ddf4 | 2020-05-12 15:19:14 +0300 | [diff] [blame] | 6898 | (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP)) { |
| 6899 | /* Add to kallsyms before the perf events */ |
Adrian Hunter | fc0ea79 | 2020-05-12 15:19:13 +0300 | [diff] [blame] | 6900 | ftrace_add_trampoline_to_kallsyms(ops); |
Adrian Hunter | dd9ddf4 | 2020-05-12 15:19:14 +0300 | [diff] [blame] | 6901 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, |
| 6902 | ops->trampoline, ops->trampoline_size, false, |
| 6903 | FTRACE_TRAMPOLINE_SYM); |
Adrian Hunter | 548e1f6 | 2020-05-12 15:19:15 +0300 | [diff] [blame] | 6904 | /* |
| 6905 | * Record the perf text poke event after the ksymbol register |
| 6906 | * event. |
| 6907 | */ |
| 6908 | perf_event_text_poke((void *)ops->trampoline, NULL, 0, |
| 6909 | (void *)ops->trampoline, |
| 6910 | ops->trampoline_size); |
Adrian Hunter | dd9ddf4 | 2020-05-12 15:19:14 +0300 | [diff] [blame] | 6911 | } |
Steven Rostedt (Red Hat) | f3bea49 | 2014-07-02 23:23:31 -0400 | [diff] [blame] | 6912 | } |
| 6913 | |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 6914 | void ftrace_init_trace_array(struct trace_array *tr) |
| 6915 | { |
| 6916 | INIT_LIST_HEAD(&tr->func_probes); |
Steven Rostedt (VMware) | 673feb9 | 2017-06-23 15:26:26 -0400 | [diff] [blame] | 6917 | INIT_LIST_HEAD(&tr->mod_trace); |
| 6918 | INIT_LIST_HEAD(&tr->mod_notrace); |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 6919 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 6920 | #else |
Frederic Weisbecker | 0b6e4d56 | 2008-10-28 20:17:38 +0100 | [diff] [blame] | 6921 | |
Steven Rostedt (VMware) | 3306fc4a | 2018-11-15 12:32:38 -0500 | [diff] [blame] | 6922 | struct ftrace_ops global_ops = { |
Steven Rostedt | bd69c30 | 2011-05-03 21:55:54 -0400 | [diff] [blame] | 6923 | .func = ftrace_stub, |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 6924 | .flags = FTRACE_OPS_FL_INITIALIZED | |
Steven Rostedt (Red Hat) | e3eea14 | 2015-07-24 10:38:12 -0400 | [diff] [blame] | 6925 | FTRACE_OPS_FL_PID, |
Steven Rostedt | bd69c30 | 2011-05-03 21:55:54 -0400 | [diff] [blame] | 6926 | }; |
| 6927 | |
Frederic Weisbecker | 0b6e4d56 | 2008-10-28 20:17:38 +0100 | [diff] [blame] | 6928 | static int __init ftrace_nodyn_init(void) |
| 6929 | { |
| 6930 | ftrace_enabled = 1; |
| 6931 | return 0; |
| 6932 | } |
Steven Rostedt | 6f41567 | 2012-10-05 12:13:07 -0400 | [diff] [blame] | 6933 | core_initcall(ftrace_nodyn_init); |
Frederic Weisbecker | 0b6e4d56 | 2008-10-28 20:17:38 +0100 | [diff] [blame] | 6934 | |
Steven Rostedt (Red Hat) | 8434dc9 | 2015-01-20 12:13:40 -0500 | [diff] [blame] | 6935 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 6936 | static inline void ftrace_startup_enable(int command) { } |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 6937 | static inline void ftrace_startup_all(int command) { } |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 6938 | |
Ingo Molnar | c7aafc5 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 6939 | # define ftrace_startup_sysctl() do { } while (0) |
| 6940 | # define ftrace_shutdown_sysctl() do { } while (0) |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 6941 | |
Steven Rostedt (Red Hat) | f3bea49 | 2014-07-02 23:23:31 -0400 | [diff] [blame] | 6942 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
| 6943 | { |
| 6944 | } |
| 6945 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 6946 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
| 6947 | |
Steven Rostedt (Red Hat) | 4104d32 | 2014-01-10 17:01:58 -0500 | [diff] [blame] | 6948 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
| 6949 | { |
| 6950 | tr->ops = &global_ops; |
| 6951 | tr->ops->private = tr; |
Steven Rostedt (VMware) | 04ec7bb | 2017-04-05 13:12:55 -0400 | [diff] [blame] | 6952 | ftrace_init_trace_array(tr); |
Steven Rostedt (Red Hat) | 4104d32 | 2014-01-10 17:01:58 -0500 | [diff] [blame] | 6953 | } |
| 6954 | |
| 6955 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) |
| 6956 | { |
| 6957 | /* If we filter on pids, update to use the pid function */ |
| 6958 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { |
| 6959 | if (WARN_ON(tr->ops->func != ftrace_stub)) |
| 6960 | printk("ftrace ops had %pS for function\n", |
| 6961 | tr->ops->func); |
Steven Rostedt (Red Hat) | 4104d32 | 2014-01-10 17:01:58 -0500 | [diff] [blame] | 6962 | } |
| 6963 | tr->ops->func = func; |
| 6964 | tr->ops->private = tr; |
| 6965 | } |
| 6966 | |
| 6967 | void ftrace_reset_array_ops(struct trace_array *tr) |
| 6968 | { |
| 6969 | tr->ops->func = ftrace_stub; |
| 6970 | } |
| 6971 | |
Masami Hiramatsu | fabe38a | 2019-02-24 01:50:20 +0900 | [diff] [blame] | 6972 | static nokprobe_inline void |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 6973 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 6974 | struct ftrace_ops *ignored, struct ftrace_regs *fregs) |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 6975 | { |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 6976 | struct pt_regs *regs = ftrace_get_regs(fregs); |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 6977 | struct ftrace_ops *op; |
Steven Rostedt | edc15ca | 2012-11-02 17:47:21 -0400 | [diff] [blame] | 6978 | int bit; |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 6979 | |
Steven Rostedt (VMware) | 773c167 | 2020-11-05 21:32:46 -0500 | [diff] [blame] | 6980 | bit = trace_test_and_set_recursion(ip, parent_ip, TRACE_LIST_START, TRACE_LIST_MAX); |
Steven Rostedt | edc15ca | 2012-11-02 17:47:21 -0400 | [diff] [blame] | 6981 | if (bit < 0) |
| 6982 | return; |
Steven Rostedt | c29f122 | 2012-11-02 17:17:59 -0400 | [diff] [blame] | 6983 | |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 6984 | /* |
| 6985 | * Some of the ops may be dynamically allocated, |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 6986 | * they must be freed after a synchronize_rcu(). |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 6987 | */ |
| 6988 | preempt_disable_notrace(); |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 6989 | |
Steven Rostedt | 0a01640 | 2012-11-02 17:03:03 -0400 | [diff] [blame] | 6990 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
Steven Rostedt (VMware) | 2fa717a | 2019-04-11 11:46:13 -0400 | [diff] [blame] | 6991 | /* Stub functions don't need to be called nor tested */ |
| 6992 | if (op->flags & FTRACE_OPS_FL_STUB) |
| 6993 | continue; |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 6994 | /* |
| 6995 | * Check the following for each ops before calling their func: |
| 6996 | * if RCU flag is set, then rcu_is_watching() must be true |
| 6997 | * if PER_CPU is set, then ftrace_function_local_disable() |
| 6998 | * must be false |
| 6999 | * Otherwise test if the ip matches the ops filter |
| 7000 | * |
| 7001 | * If any of the above fails then the op->func() is not executed. |
| 7002 | */ |
| 7003 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && |
Steven Rostedt (Red Hat) | ba27f2b | 2015-11-30 17:23:39 -0500 | [diff] [blame] | 7004 | ftrace_ops_test(op, ip, regs)) { |
Steven Rostedt (Red Hat) | 1d48d59 | 2014-06-25 11:54:03 -0400 | [diff] [blame] | 7005 | if (FTRACE_WARN_ON(!op->func)) { |
| 7006 | pr_warn("op=%p %pS\n", op, op); |
Steven Rostedt (Red Hat) | 4104d32 | 2014-01-10 17:01:58 -0500 | [diff] [blame] | 7007 | goto out; |
| 7008 | } |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 7009 | op->func(ip, parent_ip, op, fregs); |
Steven Rostedt (Red Hat) | 4104d32 | 2014-01-10 17:01:58 -0500 | [diff] [blame] | 7010 | } |
Steven Rostedt | 0a01640 | 2012-11-02 17:03:03 -0400 | [diff] [blame] | 7011 | } while_for_each_ftrace_op(op); |
Steven Rostedt (Red Hat) | 4104d32 | 2014-01-10 17:01:58 -0500 | [diff] [blame] | 7012 | out: |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 7013 | preempt_enable_notrace(); |
Steven Rostedt | edc15ca | 2012-11-02 17:47:21 -0400 | [diff] [blame] | 7014 | trace_clear_recursion(bit); |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 7015 | } |
| 7016 | |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7017 | /* |
| 7018 | * Some archs only support passing ip and parent_ip. Even though |
| 7019 | * the list function ignores the op parameter, we do not want any |
| 7020 | * C side effects, where a function is called without the caller |
| 7021 | * sending a third parameter. |
Steven Rostedt | a1e2e31 | 2011-08-09 12:50:46 -0400 | [diff] [blame] | 7022 | * Archs are to support both the regs and ftrace_ops at the same time. |
| 7023 | * If they support ftrace_ops, it is assumed they support regs. |
| 7024 | * If call backs want to use regs, they must either check for regs |
Masami Hiramatsu | 06aeaae | 2012-09-28 17:15:17 +0900 | [diff] [blame] | 7025 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
| 7026 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. |
Steven Rostedt | a1e2e31 | 2011-08-09 12:50:46 -0400 | [diff] [blame] | 7027 | * An architecture can pass partial regs with ftrace_ops and still |
Li Bin | b8ec330 | 2015-11-30 18:23:36 +0800 | [diff] [blame] | 7028 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7029 | */ |
| 7030 | #if ARCH_SUPPORTS_FTRACE_OPS |
| 7031 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 7032 | struct ftrace_ops *op, struct ftrace_regs *fregs) |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7033 | { |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 7034 | __ftrace_ops_list_func(ip, parent_ip, NULL, fregs); |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7035 | } |
Masami Hiramatsu | fabe38a | 2019-02-24 01:50:20 +0900 | [diff] [blame] | 7036 | NOKPROBE_SYMBOL(ftrace_ops_list_func); |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7037 | #else |
| 7038 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) |
| 7039 | { |
Steven Rostedt | a1e2e31 | 2011-08-09 12:50:46 -0400 | [diff] [blame] | 7040 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7041 | } |
Masami Hiramatsu | fabe38a | 2019-02-24 01:50:20 +0900 | [diff] [blame] | 7042 | NOKPROBE_SYMBOL(ftrace_ops_no_ops); |
Steven Rostedt | 2f5f6ad | 2011-08-08 16:57:47 -0400 | [diff] [blame] | 7043 | #endif |
| 7044 | |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7045 | /* |
| 7046 | * If there's only one function registered but it does not support |
Steven Rostedt (Red Hat) | c68c0fa | 2015-12-01 13:28:16 -0500 | [diff] [blame] | 7047 | * recursion, needs RCU protection and/or requires per cpu handling, then |
| 7048 | * this function will be called by the mcount trampoline. |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7049 | */ |
Steven Rostedt (Red Hat) | c68c0fa | 2015-12-01 13:28:16 -0500 | [diff] [blame] | 7050 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 7051 | struct ftrace_ops *op, struct ftrace_regs *fregs) |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7052 | { |
| 7053 | int bit; |
| 7054 | |
Steven Rostedt (VMware) | 773c167 | 2020-11-05 21:32:46 -0500 | [diff] [blame] | 7055 | bit = trace_test_and_set_recursion(ip, parent_ip, TRACE_LIST_START, TRACE_LIST_MAX); |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7056 | if (bit < 0) |
| 7057 | return; |
| 7058 | |
Steven Rostedt (Red Hat) | c68c0fa | 2015-12-01 13:28:16 -0500 | [diff] [blame] | 7059 | preempt_disable_notrace(); |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7060 | |
Steven Rostedt (VMware) | b40341f | 2020-09-29 12:40:31 -0400 | [diff] [blame] | 7061 | if (!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) |
Steven Rostedt (VMware) | d19ad07 | 2020-10-28 17:42:17 -0400 | [diff] [blame] | 7062 | op->func(ip, parent_ip, op, fregs); |
Steven Rostedt (Red Hat) | c68c0fa | 2015-12-01 13:28:16 -0500 | [diff] [blame] | 7063 | |
| 7064 | preempt_enable_notrace(); |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7065 | trace_clear_recursion(bit); |
| 7066 | } |
Masami Hiramatsu | fabe38a | 2019-02-24 01:50:20 +0900 | [diff] [blame] | 7067 | NOKPROBE_SYMBOL(ftrace_ops_assist_func); |
Steven Rostedt (Red Hat) | f1ff634 | 2014-07-22 20:16:57 -0400 | [diff] [blame] | 7068 | |
Steven Rostedt (Red Hat) | 8735405 | 2014-07-22 20:41:42 -0400 | [diff] [blame] | 7069 | /** |
| 7070 | * ftrace_ops_get_func - get the function a trampoline should call |
| 7071 | * @ops: the ops to get the function for |
| 7072 | * |
| 7073 | * Normally the mcount trampoline will call the ops->func, but there |
| 7074 | * are times that it should not. For example, if the ops does not |
| 7075 | * have its own recursion protection, then it should call the |
Chunyu Hu | 3a150df | 2017-02-22 08:29:26 +0800 | [diff] [blame] | 7076 | * ftrace_ops_assist_func() instead. |
Steven Rostedt (Red Hat) | 8735405 | 2014-07-22 20:41:42 -0400 | [diff] [blame] | 7077 | * |
| 7078 | * Returns the function that the trampoline should call for @ops. |
| 7079 | */ |
| 7080 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) |
| 7081 | { |
| 7082 | /* |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 7083 | * If the function does not handle recursion or needs to be RCU safe, |
| 7084 | * then we need to call the assist handler. |
Steven Rostedt (Red Hat) | 8735405 | 2014-07-22 20:41:42 -0400 | [diff] [blame] | 7085 | */ |
Steven Rostedt (VMware) | a25d036 | 2020-11-05 21:32:45 -0500 | [diff] [blame] | 7086 | if (ops->flags & (FTRACE_OPS_FL_RECURSION | |
| 7087 | FTRACE_OPS_FL_RCU)) |
Steven Rostedt (Red Hat) | c68c0fa | 2015-12-01 13:28:16 -0500 | [diff] [blame] | 7088 | return ftrace_ops_assist_func; |
Steven Rostedt (Red Hat) | 8735405 | 2014-07-22 20:41:42 -0400 | [diff] [blame] | 7089 | |
| 7090 | return ops->func; |
| 7091 | } |
| 7092 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7093 | static void |
| 7094 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, |
| 7095 | struct task_struct *prev, struct task_struct *next) |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 7096 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7097 | struct trace_array *tr = data; |
| 7098 | struct trace_pid_list *pid_list; |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7099 | struct trace_pid_list *no_pid_list; |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7100 | |
| 7101 | pid_list = rcu_dereference_sched(tr->function_pids); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7102 | no_pid_list = rcu_dereference_sched(tr->function_no_pids); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7103 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7104 | if (trace_ignore_this_task(pid_list, no_pid_list, next)) |
Steven Rostedt (VMware) | 717e3f5 | 2020-03-19 23:40:40 -0400 | [diff] [blame] | 7105 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, |
| 7106 | FTRACE_PID_IGNORE); |
| 7107 | else |
| 7108 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, |
| 7109 | next->pid); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7110 | } |
| 7111 | |
Namhyung Kim | 1e10486 | 2017-04-17 11:44:28 +0900 | [diff] [blame] | 7112 | static void |
| 7113 | ftrace_pid_follow_sched_process_fork(void *data, |
| 7114 | struct task_struct *self, |
| 7115 | struct task_struct *task) |
| 7116 | { |
| 7117 | struct trace_pid_list *pid_list; |
| 7118 | struct trace_array *tr = data; |
| 7119 | |
| 7120 | pid_list = rcu_dereference_sched(tr->function_pids); |
| 7121 | trace_filter_add_remove_task(pid_list, self, task); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7122 | |
| 7123 | pid_list = rcu_dereference_sched(tr->function_no_pids); |
| 7124 | trace_filter_add_remove_task(pid_list, self, task); |
Namhyung Kim | 1e10486 | 2017-04-17 11:44:28 +0900 | [diff] [blame] | 7125 | } |
| 7126 | |
| 7127 | static void |
| 7128 | ftrace_pid_follow_sched_process_exit(void *data, struct task_struct *task) |
| 7129 | { |
| 7130 | struct trace_pid_list *pid_list; |
| 7131 | struct trace_array *tr = data; |
| 7132 | |
| 7133 | pid_list = rcu_dereference_sched(tr->function_pids); |
| 7134 | trace_filter_add_remove_task(pid_list, NULL, task); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7135 | |
| 7136 | pid_list = rcu_dereference_sched(tr->function_no_pids); |
| 7137 | trace_filter_add_remove_task(pid_list, NULL, task); |
Namhyung Kim | 1e10486 | 2017-04-17 11:44:28 +0900 | [diff] [blame] | 7138 | } |
| 7139 | |
| 7140 | void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) |
| 7141 | { |
| 7142 | if (enable) { |
| 7143 | register_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, |
| 7144 | tr); |
Steven Rostedt (VMware) | afcab63 | 2020-08-04 20:00:02 -0400 | [diff] [blame] | 7145 | register_trace_sched_process_free(ftrace_pid_follow_sched_process_exit, |
Namhyung Kim | 1e10486 | 2017-04-17 11:44:28 +0900 | [diff] [blame] | 7146 | tr); |
| 7147 | } else { |
| 7148 | unregister_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, |
| 7149 | tr); |
Steven Rostedt (VMware) | afcab63 | 2020-08-04 20:00:02 -0400 | [diff] [blame] | 7150 | unregister_trace_sched_process_free(ftrace_pid_follow_sched_process_exit, |
Namhyung Kim | 1e10486 | 2017-04-17 11:44:28 +0900 | [diff] [blame] | 7151 | tr); |
| 7152 | } |
| 7153 | } |
| 7154 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7155 | static void clear_ftrace_pids(struct trace_array *tr, int type) |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7156 | { |
| 7157 | struct trace_pid_list *pid_list; |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7158 | struct trace_pid_list *no_pid_list; |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 7159 | int cpu; |
| 7160 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7161 | pid_list = rcu_dereference_protected(tr->function_pids, |
| 7162 | lockdep_is_held(&ftrace_lock)); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7163 | no_pid_list = rcu_dereference_protected(tr->function_no_pids, |
| 7164 | lockdep_is_held(&ftrace_lock)); |
| 7165 | |
| 7166 | /* Make sure there's something to do */ |
Steven Rostedt (VMware) | 2768362 | 2020-03-25 19:51:19 -0400 | [diff] [blame] | 7167 | if (!pid_type_enabled(type, pid_list, no_pid_list)) |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7168 | return; |
| 7169 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7170 | /* See if the pids still need to be checked after this */ |
Steven Rostedt (VMware) | 2768362 | 2020-03-25 19:51:19 -0400 | [diff] [blame] | 7171 | if (!still_need_pid_events(type, pid_list, no_pid_list)) { |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7172 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
| 7173 | for_each_possible_cpu(cpu) |
| 7174 | per_cpu_ptr(tr->array_buffer.data, cpu)->ftrace_ignore_pid = FTRACE_PID_TRACE; |
| 7175 | } |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7176 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7177 | if (type & TRACE_PIDS) |
| 7178 | rcu_assign_pointer(tr->function_pids, NULL); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7179 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7180 | if (type & TRACE_NO_PIDS) |
| 7181 | rcu_assign_pointer(tr->function_no_pids, NULL); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7182 | |
| 7183 | /* Wait till all users are no longer using pid filtering */ |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 7184 | synchronize_rcu(); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7185 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7186 | if ((type & TRACE_PIDS) && pid_list) |
| 7187 | trace_free_pid_list(pid_list); |
| 7188 | |
| 7189 | if ((type & TRACE_NO_PIDS) && no_pid_list) |
| 7190 | trace_free_pid_list(no_pid_list); |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 7191 | } |
| 7192 | |
Namhyung Kim | d879d0b | 2017-04-17 11:44:27 +0900 | [diff] [blame] | 7193 | void ftrace_clear_pids(struct trace_array *tr) |
| 7194 | { |
| 7195 | mutex_lock(&ftrace_lock); |
| 7196 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7197 | clear_ftrace_pids(tr, TRACE_PIDS | TRACE_NO_PIDS); |
Namhyung Kim | d879d0b | 2017-04-17 11:44:27 +0900 | [diff] [blame] | 7198 | |
| 7199 | mutex_unlock(&ftrace_lock); |
| 7200 | } |
| 7201 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7202 | static void ftrace_pid_reset(struct trace_array *tr, int type) |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 7203 | { |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7204 | mutex_lock(&ftrace_lock); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7205 | clear_ftrace_pids(tr, type); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7206 | |
| 7207 | ftrace_update_pid_func(); |
Steven Rostedt (Red Hat) | e1effa0 | 2014-08-05 17:19:38 -0400 | [diff] [blame] | 7208 | ftrace_startup_all(0); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7209 | |
| 7210 | mutex_unlock(&ftrace_lock); |
| 7211 | } |
| 7212 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7213 | /* Greater than any max PID */ |
| 7214 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) |
| 7215 | |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7216 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7217 | __acquires(RCU) |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7218 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7219 | struct trace_pid_list *pid_list; |
| 7220 | struct trace_array *tr = m->private; |
| 7221 | |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7222 | mutex_lock(&ftrace_lock); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7223 | rcu_read_lock_sched(); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7224 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7225 | pid_list = rcu_dereference_sched(tr->function_pids); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7226 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7227 | if (!pid_list) |
| 7228 | return !(*pos) ? FTRACE_NO_PIDS : NULL; |
| 7229 | |
| 7230 | return trace_pid_start(pid_list, pos); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7231 | } |
| 7232 | |
| 7233 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) |
| 7234 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7235 | struct trace_array *tr = m->private; |
| 7236 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); |
| 7237 | |
Vasily Averin | e4075e8 | 2020-01-24 10:02:56 +0300 | [diff] [blame] | 7238 | if (v == FTRACE_NO_PIDS) { |
| 7239 | (*pos)++; |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7240 | return NULL; |
Vasily Averin | e4075e8 | 2020-01-24 10:02:56 +0300 | [diff] [blame] | 7241 | } |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7242 | return trace_pid_next(pid_list, v, pos); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7243 | } |
| 7244 | |
| 7245 | static void fpid_stop(struct seq_file *m, void *p) |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7246 | __releases(RCU) |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7247 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7248 | rcu_read_unlock_sched(); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7249 | mutex_unlock(&ftrace_lock); |
| 7250 | } |
| 7251 | |
| 7252 | static int fpid_show(struct seq_file *m, void *v) |
| 7253 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7254 | if (v == FTRACE_NO_PIDS) { |
Rasmus Villemoes | fa6f0cc | 2014-11-08 21:42:10 +0100 | [diff] [blame] | 7255 | seq_puts(m, "no pid\n"); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7256 | return 0; |
| 7257 | } |
| 7258 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7259 | return trace_pid_show(m, v); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7260 | } |
| 7261 | |
| 7262 | static const struct seq_operations ftrace_pid_sops = { |
| 7263 | .start = fpid_start, |
| 7264 | .next = fpid_next, |
| 7265 | .stop = fpid_stop, |
| 7266 | .show = fpid_show, |
| 7267 | }; |
| 7268 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7269 | static void *fnpid_start(struct seq_file *m, loff_t *pos) |
| 7270 | __acquires(RCU) |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7271 | { |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7272 | struct trace_pid_list *pid_list; |
| 7273 | struct trace_array *tr = m->private; |
| 7274 | |
| 7275 | mutex_lock(&ftrace_lock); |
| 7276 | rcu_read_lock_sched(); |
| 7277 | |
| 7278 | pid_list = rcu_dereference_sched(tr->function_no_pids); |
| 7279 | |
| 7280 | if (!pid_list) |
| 7281 | return !(*pos) ? FTRACE_NO_PIDS : NULL; |
| 7282 | |
| 7283 | return trace_pid_start(pid_list, pos); |
| 7284 | } |
| 7285 | |
| 7286 | static void *fnpid_next(struct seq_file *m, void *v, loff_t *pos) |
| 7287 | { |
| 7288 | struct trace_array *tr = m->private; |
| 7289 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_no_pids); |
| 7290 | |
| 7291 | if (v == FTRACE_NO_PIDS) { |
| 7292 | (*pos)++; |
| 7293 | return NULL; |
| 7294 | } |
| 7295 | return trace_pid_next(pid_list, v, pos); |
| 7296 | } |
| 7297 | |
| 7298 | static const struct seq_operations ftrace_no_pid_sops = { |
| 7299 | .start = fnpid_start, |
| 7300 | .next = fnpid_next, |
| 7301 | .stop = fpid_stop, |
| 7302 | .show = fpid_show, |
| 7303 | }; |
| 7304 | |
| 7305 | static int pid_open(struct inode *inode, struct file *file, int type) |
| 7306 | { |
| 7307 | const struct seq_operations *seq_ops; |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7308 | struct trace_array *tr = inode->i_private; |
| 7309 | struct seq_file *m; |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7310 | int ret = 0; |
| 7311 | |
Steven Rostedt (VMware) | 8530dec | 2019-10-11 17:39:57 -0400 | [diff] [blame] | 7312 | ret = tracing_check_open_get_tr(tr); |
| 7313 | if (ret) |
| 7314 | return ret; |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7315 | |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7316 | if ((file->f_mode & FMODE_WRITE) && |
| 7317 | (file->f_flags & O_TRUNC)) |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7318 | ftrace_pid_reset(tr, type); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7319 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7320 | switch (type) { |
| 7321 | case TRACE_PIDS: |
| 7322 | seq_ops = &ftrace_pid_sops; |
| 7323 | break; |
| 7324 | case TRACE_NO_PIDS: |
| 7325 | seq_ops = &ftrace_no_pid_sops; |
| 7326 | break; |
Kaitao Cheng | 026bb84 | 2020-05-29 22:12:14 +0800 | [diff] [blame] | 7327 | default: |
| 7328 | trace_array_put(tr); |
| 7329 | WARN_ON_ONCE(1); |
| 7330 | return -EINVAL; |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7331 | } |
| 7332 | |
| 7333 | ret = seq_open(file, seq_ops); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7334 | if (ret < 0) { |
| 7335 | trace_array_put(tr); |
| 7336 | } else { |
| 7337 | m = file->private_data; |
| 7338 | /* copy tr over to seq ops */ |
| 7339 | m->private = tr; |
| 7340 | } |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7341 | |
| 7342 | return ret; |
| 7343 | } |
| 7344 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7345 | static int |
| 7346 | ftrace_pid_open(struct inode *inode, struct file *file) |
| 7347 | { |
| 7348 | return pid_open(inode, file, TRACE_PIDS); |
| 7349 | } |
| 7350 | |
| 7351 | static int |
| 7352 | ftrace_no_pid_open(struct inode *inode, struct file *file) |
| 7353 | { |
| 7354 | return pid_open(inode, file, TRACE_NO_PIDS); |
| 7355 | } |
| 7356 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7357 | static void ignore_task_cpu(void *data) |
| 7358 | { |
| 7359 | struct trace_array *tr = data; |
| 7360 | struct trace_pid_list *pid_list; |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7361 | struct trace_pid_list *no_pid_list; |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7362 | |
| 7363 | /* |
| 7364 | * This function is called by on_each_cpu() while the |
| 7365 | * event_mutex is held. |
| 7366 | */ |
| 7367 | pid_list = rcu_dereference_protected(tr->function_pids, |
| 7368 | mutex_is_locked(&ftrace_lock)); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7369 | no_pid_list = rcu_dereference_protected(tr->function_no_pids, |
| 7370 | mutex_is_locked(&ftrace_lock)); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7371 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7372 | if (trace_ignore_this_task(pid_list, no_pid_list, current)) |
Steven Rostedt (VMware) | 717e3f5 | 2020-03-19 23:40:40 -0400 | [diff] [blame] | 7373 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, |
| 7374 | FTRACE_PID_IGNORE); |
| 7375 | else |
| 7376 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, |
| 7377 | current->pid); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7378 | } |
| 7379 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7380 | static ssize_t |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7381 | pid_write(struct file *filp, const char __user *ubuf, |
| 7382 | size_t cnt, loff_t *ppos, int type) |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7383 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7384 | struct seq_file *m = filp->private_data; |
| 7385 | struct trace_array *tr = m->private; |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7386 | struct trace_pid_list *filtered_pids; |
| 7387 | struct trace_pid_list *other_pids; |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7388 | struct trace_pid_list *pid_list; |
| 7389 | ssize_t ret; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7390 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7391 | if (!cnt) |
| 7392 | return 0; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7393 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7394 | mutex_lock(&ftrace_lock); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7395 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7396 | switch (type) { |
| 7397 | case TRACE_PIDS: |
| 7398 | filtered_pids = rcu_dereference_protected(tr->function_pids, |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7399 | lockdep_is_held(&ftrace_lock)); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7400 | other_pids = rcu_dereference_protected(tr->function_no_pids, |
| 7401 | lockdep_is_held(&ftrace_lock)); |
| 7402 | break; |
| 7403 | case TRACE_NO_PIDS: |
| 7404 | filtered_pids = rcu_dereference_protected(tr->function_no_pids, |
| 7405 | lockdep_is_held(&ftrace_lock)); |
| 7406 | other_pids = rcu_dereference_protected(tr->function_pids, |
| 7407 | lockdep_is_held(&ftrace_lock)); |
| 7408 | break; |
Kaitao Cheng | 026bb84 | 2020-05-29 22:12:14 +0800 | [diff] [blame] | 7409 | default: |
| 7410 | ret = -EINVAL; |
| 7411 | WARN_ON_ONCE(1); |
| 7412 | goto out; |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7413 | } |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7414 | |
| 7415 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); |
| 7416 | if (ret < 0) |
| 7417 | goto out; |
| 7418 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7419 | switch (type) { |
| 7420 | case TRACE_PIDS: |
| 7421 | rcu_assign_pointer(tr->function_pids, pid_list); |
| 7422 | break; |
| 7423 | case TRACE_NO_PIDS: |
| 7424 | rcu_assign_pointer(tr->function_no_pids, pid_list); |
| 7425 | break; |
| 7426 | } |
| 7427 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7428 | |
| 7429 | if (filtered_pids) { |
Paul E. McKenney | 7440172 | 2018-11-06 18:44:52 -0800 | [diff] [blame] | 7430 | synchronize_rcu(); |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7431 | trace_free_pid_list(filtered_pids); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7432 | } else if (pid_list && !other_pids) { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7433 | /* Register a probe to set whether to ignore the tracing of a task */ |
| 7434 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
| 7435 | } |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7436 | |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7437 | /* |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7438 | * Ignoring of pids is done at task switch. But we have to |
| 7439 | * check for those tasks that are currently running. |
| 7440 | * Always do this in case a pid was appended or removed. |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7441 | */ |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7442 | on_each_cpu(ignore_task_cpu, tr, 1); |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7443 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7444 | ftrace_update_pid_func(); |
| 7445 | ftrace_startup_all(0); |
| 7446 | out: |
| 7447 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7448 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7449 | if (ret > 0) |
| 7450 | *ppos += ret; |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 7451 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7452 | return ret; |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7453 | } |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7454 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7455 | static ssize_t |
| 7456 | ftrace_pid_write(struct file *filp, const char __user *ubuf, |
| 7457 | size_t cnt, loff_t *ppos) |
| 7458 | { |
| 7459 | return pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS); |
| 7460 | } |
| 7461 | |
| 7462 | static ssize_t |
| 7463 | ftrace_no_pid_write(struct file *filp, const char __user *ubuf, |
| 7464 | size_t cnt, loff_t *ppos) |
| 7465 | { |
| 7466 | return pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS); |
| 7467 | } |
| 7468 | |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7469 | static int |
| 7470 | ftrace_pid_release(struct inode *inode, struct file *file) |
| 7471 | { |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7472 | struct trace_array *tr = inode->i_private; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7473 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7474 | trace_array_put(tr); |
| 7475 | |
| 7476 | return seq_release(inode, file); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7477 | } |
| 7478 | |
Steven Rostedt | 5e2336a | 2009-03-05 21:44:55 -0500 | [diff] [blame] | 7479 | static const struct file_operations ftrace_pid_fops = { |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7480 | .open = ftrace_pid_open, |
| 7481 | .write = ftrace_pid_write, |
| 7482 | .read = seq_read, |
Steven Rostedt (Red Hat) | 098c879e | 2013-12-21 17:39:40 -0500 | [diff] [blame] | 7483 | .llseek = tracing_lseek, |
jolsa@redhat.com | 756d17e | 2009-10-13 16:33:52 -0400 | [diff] [blame] | 7484 | .release = ftrace_pid_release, |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7485 | }; |
| 7486 | |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7487 | static const struct file_operations ftrace_no_pid_fops = { |
| 7488 | .open = ftrace_no_pid_open, |
| 7489 | .write = ftrace_no_pid_write, |
| 7490 | .read = seq_read, |
| 7491 | .llseek = tracing_lseek, |
| 7492 | .release = ftrace_pid_release, |
| 7493 | }; |
| 7494 | |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7495 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7496 | { |
Frederic Weisbecker | 5452af6 | 2009-03-27 00:25:38 +0100 | [diff] [blame] | 7497 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
Steven Rostedt (Red Hat) | 345ddcc | 2016-04-22 18:11:33 -0400 | [diff] [blame] | 7498 | tr, &ftrace_pid_fops); |
Steven Rostedt (VMware) | b3b1e6e | 2020-03-19 23:19:06 -0400 | [diff] [blame] | 7499 | trace_create_file("set_ftrace_notrace_pid", 0644, d_tracer, |
| 7500 | tr, &ftrace_no_pid_fops); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7501 | } |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 7502 | |
Steven Rostedt (Red Hat) | 501c237 | 2016-07-05 10:04:34 -0400 | [diff] [blame] | 7503 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
| 7504 | struct dentry *d_tracer) |
| 7505 | { |
| 7506 | /* Only the top level directory has the dyn_tracefs and profile */ |
| 7507 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); |
| 7508 | |
| 7509 | ftrace_init_dyn_tracefs(d_tracer); |
| 7510 | ftrace_profile_tracefs(d_tracer); |
| 7511 | } |
| 7512 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7513 | /** |
Steven Rostedt | 81adbdc | 2008-10-23 09:33:02 -0400 | [diff] [blame] | 7514 | * ftrace_kill - kill ftrace |
Steven Rostedt | a2bb6a3 | 2008-07-10 20:58:15 -0400 | [diff] [blame] | 7515 | * |
| 7516 | * This function should be used by panic code. It stops ftrace |
| 7517 | * but in a not so nice way. If you need to simply kill ftrace |
| 7518 | * from a non-atomic section, use ftrace_kill. |
| 7519 | */ |
Steven Rostedt | 81adbdc | 2008-10-23 09:33:02 -0400 | [diff] [blame] | 7520 | void ftrace_kill(void) |
Steven Rostedt | a2bb6a3 | 2008-07-10 20:58:15 -0400 | [diff] [blame] | 7521 | { |
| 7522 | ftrace_disabled = 1; |
| 7523 | ftrace_enabled = 0; |
Yisheng Xie | 5ccba64 | 2018-02-02 10:14:49 +0800 | [diff] [blame] | 7524 | ftrace_trace_function = ftrace_stub; |
Steven Rostedt | a2bb6a3 | 2008-07-10 20:58:15 -0400 | [diff] [blame] | 7525 | } |
| 7526 | |
| 7527 | /** |
Steven Rostedt | e0a413f | 2011-09-29 21:26:16 -0400 | [diff] [blame] | 7528 | * Test if ftrace is dead or not. |
| 7529 | */ |
| 7530 | int ftrace_is_dead(void) |
| 7531 | { |
| 7532 | return ftrace_disabled; |
| 7533 | } |
| 7534 | |
| 7535 | /** |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7536 | * register_ftrace_function - register a function for profiling |
| 7537 | * @ops - ops structure that holds the function for profiling. |
| 7538 | * |
| 7539 | * Register a function to be called by all functions in the |
| 7540 | * kernel. |
| 7541 | * |
| 7542 | * Note: @ops->func and all the functions it calls must be labeled |
| 7543 | * with "notrace", otherwise it will go into a |
| 7544 | * recursive loop. |
| 7545 | */ |
| 7546 | int register_ftrace_function(struct ftrace_ops *ops) |
| 7547 | { |
Colin Ian King | 3b1a8f4 | 2021-07-21 13:09:15 +0100 | [diff] [blame] | 7548 | int ret; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 7549 | |
Masami Hiramatsu | f04f24fb | 2013-05-09 14:44:17 +0900 | [diff] [blame] | 7550 | ftrace_ops_init(ops); |
| 7551 | |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 7552 | mutex_lock(&ftrace_lock); |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 7553 | |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 7554 | ret = ftrace_startup(ops, 0); |
Steven Rostedt | b848914 | 2011-05-04 09:27:52 -0400 | [diff] [blame] | 7555 | |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 7556 | mutex_unlock(&ftrace_lock); |
Borislav Petkov | 8d240dd | 2012-03-29 19:11:40 +0200 | [diff] [blame] | 7557 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7558 | return ret; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7559 | } |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 7560 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7561 | |
| 7562 | /** |
Uwe Kleine-Koenig | 3263292 | 2009-01-12 23:35:50 +0100 | [diff] [blame] | 7563 | * unregister_ftrace_function - unregister a function for profiling. |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7564 | * @ops - ops structure that holds the function to unregister |
| 7565 | * |
| 7566 | * Unregister a function that was added to be called by ftrace profiling. |
| 7567 | */ |
| 7568 | int unregister_ftrace_function(struct ftrace_ops *ops) |
| 7569 | { |
| 7570 | int ret; |
| 7571 | |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 7572 | mutex_lock(&ftrace_lock); |
Steven Rostedt (Red Hat) | 8a56d77 | 2013-11-25 20:59:46 -0500 | [diff] [blame] | 7573 | ret = ftrace_shutdown(ops, 0); |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 7574 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7575 | |
| 7576 | return ret; |
| 7577 | } |
Steven Rostedt | cdbe61b | 2011-05-05 21:14:55 -0400 | [diff] [blame] | 7578 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7579 | |
Miroslav Benes | 7162431 | 2019-10-16 13:33:13 +0200 | [diff] [blame] | 7580 | static bool is_permanent_ops_registered(void) |
| 7581 | { |
| 7582 | struct ftrace_ops *op; |
| 7583 | |
| 7584 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
| 7585 | if (op->flags & FTRACE_OPS_FL_PERMANENT) |
| 7586 | return true; |
| 7587 | } while_for_each_ftrace_op(op); |
| 7588 | |
| 7589 | return false; |
| 7590 | } |
| 7591 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 7592 | int |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7593 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
Tobias Klauser | 54fa9ba | 2020-09-07 11:32:07 +0200 | [diff] [blame] | 7594 | void *buffer, size_t *lenp, loff_t *ppos) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7595 | { |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 7596 | int ret = -ENODEV; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 7597 | |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 7598 | mutex_lock(&ftrace_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7599 | |
Steven Rostedt | 45a4a23 | 2011-04-21 23:16:46 -0400 | [diff] [blame] | 7600 | if (unlikely(ftrace_disabled)) |
| 7601 | goto out; |
| 7602 | |
| 7603 | ret = proc_dointvec(table, write, buffer, lenp, ppos); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7604 | |
Li Zefan | a32c776 | 2009-06-26 16:55:51 +0800 | [diff] [blame] | 7605 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7606 | goto out; |
| 7607 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7608 | if (ftrace_enabled) { |
| 7609 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7610 | /* we are starting ftrace again */ |
Chunyan Zhang | f86f418 | 2017-06-07 16:12:51 +0800 | [diff] [blame] | 7611 | if (rcu_dereference_protected(ftrace_ops_list, |
| 7612 | lockdep_is_held(&ftrace_lock)) != &ftrace_list_end) |
Jan Kiszka | 5000c41 | 2013-03-26 17:53:03 +0100 | [diff] [blame] | 7613 | update_ftrace_function(); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7614 | |
Steven Rostedt (Red Hat) | 524a386 | 2015-03-06 19:55:13 -0500 | [diff] [blame] | 7615 | ftrace_startup_sysctl(); |
| 7616 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7617 | } else { |
Miroslav Benes | 7162431 | 2019-10-16 13:33:13 +0200 | [diff] [blame] | 7618 | if (is_permanent_ops_registered()) { |
| 7619 | ftrace_enabled = true; |
| 7620 | ret = -EBUSY; |
| 7621 | goto out; |
| 7622 | } |
| 7623 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7624 | /* stopping ftrace calls (just send to ftrace_stub) */ |
| 7625 | ftrace_trace_function = ftrace_stub; |
| 7626 | |
| 7627 | ftrace_shutdown_sysctl(); |
| 7628 | } |
| 7629 | |
Miroslav Benes | 7162431 | 2019-10-16 13:33:13 +0200 | [diff] [blame] | 7630 | last_ftrace_enabled = !!ftrace_enabled; |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 7631 | out: |
Steven Rostedt | e6ea44e | 2009-02-14 01:42:44 -0500 | [diff] [blame] | 7632 | mutex_unlock(&ftrace_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7633 | return ret; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 7634 | } |