Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1 | /* |
Masami Hiramatsu | 77b44d1 | 2009-11-03 19:12:47 -0500 | [diff] [blame] | 2 | * Kprobes-based tracing events |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 3 | * |
| 4 | * Created by Masami Hiramatsu <mhiramat@redhat.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 18 | */ |
| 19 | |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/uaccess.h> |
| 22 | #include <linux/kprobes.h> |
| 23 | #include <linux/seq_file.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <linux/smp.h> |
| 26 | #include <linux/debugfs.h> |
| 27 | #include <linux/types.h> |
| 28 | #include <linux/string.h> |
| 29 | #include <linux/ctype.h> |
| 30 | #include <linux/ptrace.h> |
Frederic Weisbecker | d7a4b41 | 2009-09-23 23:08:43 +0200 | [diff] [blame] | 31 | #include <linux/perf_event.h> |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 32 | |
| 33 | #include "trace.h" |
| 34 | #include "trace_output.h" |
| 35 | |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 36 | #define MAX_TRACE_ARGS 128 |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 37 | #define MAX_ARGSTR_LEN 63 |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 38 | #define MAX_EVENT_NAME_LEN 64 |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 39 | #define KPROBE_EVENT_SYSTEM "kprobes" |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 40 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 41 | /* Reserved field names */ |
Masami Hiramatsu | e93f4d8 | 2009-10-07 18:28:14 -0400 | [diff] [blame] | 42 | #define FIELD_STRING_IP "__probe_ip" |
| 43 | #define FIELD_STRING_NARGS "__probe_nargs" |
| 44 | #define FIELD_STRING_RETIP "__probe_ret_ip" |
| 45 | #define FIELD_STRING_FUNC "__probe_func" |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 46 | |
| 47 | const char *reserved_field_names[] = { |
| 48 | "common_type", |
| 49 | "common_flags", |
| 50 | "common_preempt_count", |
| 51 | "common_pid", |
| 52 | "common_tgid", |
| 53 | "common_lock_depth", |
| 54 | FIELD_STRING_IP, |
| 55 | FIELD_STRING_NARGS, |
| 56 | FIELD_STRING_RETIP, |
| 57 | FIELD_STRING_FUNC, |
| 58 | }; |
| 59 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 60 | struct fetch_func { |
| 61 | unsigned long (*func)(struct pt_regs *, void *); |
| 62 | void *data; |
| 63 | }; |
| 64 | |
| 65 | static __kprobes unsigned long call_fetch(struct fetch_func *f, |
| 66 | struct pt_regs *regs) |
| 67 | { |
| 68 | return f->func(regs, f->data); |
| 69 | } |
| 70 | |
| 71 | /* fetch handlers */ |
| 72 | static __kprobes unsigned long fetch_register(struct pt_regs *regs, |
| 73 | void *offset) |
| 74 | { |
| 75 | return regs_get_register(regs, (unsigned int)((unsigned long)offset)); |
| 76 | } |
| 77 | |
| 78 | static __kprobes unsigned long fetch_stack(struct pt_regs *regs, |
| 79 | void *num) |
| 80 | { |
| 81 | return regs_get_kernel_stack_nth(regs, |
| 82 | (unsigned int)((unsigned long)num)); |
| 83 | } |
| 84 | |
| 85 | static __kprobes unsigned long fetch_memory(struct pt_regs *regs, void *addr) |
| 86 | { |
| 87 | unsigned long retval; |
| 88 | |
| 89 | if (probe_kernel_address(addr, retval)) |
| 90 | return 0; |
| 91 | return retval; |
| 92 | } |
| 93 | |
| 94 | static __kprobes unsigned long fetch_argument(struct pt_regs *regs, void *num) |
| 95 | { |
| 96 | return regs_get_argument_nth(regs, (unsigned int)((unsigned long)num)); |
| 97 | } |
| 98 | |
| 99 | static __kprobes unsigned long fetch_retvalue(struct pt_regs *regs, |
| 100 | void *dummy) |
| 101 | { |
| 102 | return regs_return_value(regs); |
| 103 | } |
| 104 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 105 | static __kprobes unsigned long fetch_stack_address(struct pt_regs *regs, |
| 106 | void *dummy) |
| 107 | { |
| 108 | return kernel_stack_pointer(regs); |
| 109 | } |
| 110 | |
| 111 | /* Memory fetching by symbol */ |
| 112 | struct symbol_cache { |
| 113 | char *symbol; |
| 114 | long offset; |
| 115 | unsigned long addr; |
| 116 | }; |
| 117 | |
| 118 | static unsigned long update_symbol_cache(struct symbol_cache *sc) |
| 119 | { |
| 120 | sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); |
| 121 | if (sc->addr) |
| 122 | sc->addr += sc->offset; |
| 123 | return sc->addr; |
| 124 | } |
| 125 | |
| 126 | static void free_symbol_cache(struct symbol_cache *sc) |
| 127 | { |
| 128 | kfree(sc->symbol); |
| 129 | kfree(sc); |
| 130 | } |
| 131 | |
| 132 | static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) |
| 133 | { |
| 134 | struct symbol_cache *sc; |
| 135 | |
| 136 | if (!sym || strlen(sym) == 0) |
| 137 | return NULL; |
| 138 | sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); |
| 139 | if (!sc) |
| 140 | return NULL; |
| 141 | |
| 142 | sc->symbol = kstrdup(sym, GFP_KERNEL); |
| 143 | if (!sc->symbol) { |
| 144 | kfree(sc); |
| 145 | return NULL; |
| 146 | } |
| 147 | sc->offset = offset; |
| 148 | |
| 149 | update_symbol_cache(sc); |
| 150 | return sc; |
| 151 | } |
| 152 | |
| 153 | static __kprobes unsigned long fetch_symbol(struct pt_regs *regs, void *data) |
| 154 | { |
| 155 | struct symbol_cache *sc = data; |
| 156 | |
| 157 | if (sc->addr) |
| 158 | return fetch_memory(regs, (void *)sc->addr); |
| 159 | else |
| 160 | return 0; |
| 161 | } |
| 162 | |
| 163 | /* Special indirect memory access interface */ |
| 164 | struct indirect_fetch_data { |
| 165 | struct fetch_func orig; |
| 166 | long offset; |
| 167 | }; |
| 168 | |
| 169 | static __kprobes unsigned long fetch_indirect(struct pt_regs *regs, void *data) |
| 170 | { |
| 171 | struct indirect_fetch_data *ind = data; |
| 172 | unsigned long addr; |
| 173 | |
| 174 | addr = call_fetch(&ind->orig, regs); |
| 175 | if (addr) { |
| 176 | addr += ind->offset; |
| 177 | return fetch_memory(regs, (void *)addr); |
| 178 | } else |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | static __kprobes void free_indirect_fetch_data(struct indirect_fetch_data *data) |
| 183 | { |
| 184 | if (data->orig.func == fetch_indirect) |
| 185 | free_indirect_fetch_data(data->orig.data); |
| 186 | else if (data->orig.func == fetch_symbol) |
| 187 | free_symbol_cache(data->orig.data); |
| 188 | kfree(data); |
| 189 | } |
| 190 | |
| 191 | /** |
Masami Hiramatsu | 77b44d1 | 2009-11-03 19:12:47 -0500 | [diff] [blame] | 192 | * Kprobe event core functions |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 193 | */ |
| 194 | |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 195 | struct probe_arg { |
| 196 | struct fetch_func fetch; |
| 197 | const char *name; |
| 198 | }; |
| 199 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 200 | /* Flags for trace_probe */ |
| 201 | #define TP_FLAG_TRACE 1 |
| 202 | #define TP_FLAG_PROFILE 2 |
| 203 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 204 | struct trace_probe { |
| 205 | struct list_head list; |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 206 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
Masami Hiramatsu | cd7e7bd | 2009-08-13 16:35:42 -0400 | [diff] [blame] | 207 | unsigned long nhit; |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 208 | unsigned int flags; /* For TP_FLAG_* */ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 209 | const char *symbol; /* symbol name */ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 210 | struct ftrace_event_call call; |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 211 | struct trace_event event; |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 212 | unsigned int nr_args; |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 213 | struct probe_arg args[]; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 214 | }; |
| 215 | |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 216 | #define SIZEOF_TRACE_PROBE(n) \ |
| 217 | (offsetof(struct trace_probe, args) + \ |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 218 | (sizeof(struct probe_arg) * (n))) |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 219 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 220 | static __kprobes int probe_is_return(struct trace_probe *tp) |
| 221 | { |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 222 | return tp->rp.handler != NULL; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 223 | } |
| 224 | |
| 225 | static __kprobes const char *probe_symbol(struct trace_probe *tp) |
| 226 | { |
| 227 | return tp->symbol ? tp->symbol : "unknown"; |
| 228 | } |
| 229 | |
Masami Hiramatsu | 30a7e07 | 2009-08-21 15:43:51 -0400 | [diff] [blame] | 230 | static int probe_arg_string(char *buf, size_t n, struct fetch_func *ff) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 231 | { |
| 232 | int ret = -EINVAL; |
| 233 | |
| 234 | if (ff->func == fetch_argument) |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 235 | ret = snprintf(buf, n, "$arg%lu", (unsigned long)ff->data); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 236 | else if (ff->func == fetch_register) { |
| 237 | const char *name; |
| 238 | name = regs_query_register_name((unsigned int)((long)ff->data)); |
| 239 | ret = snprintf(buf, n, "%%%s", name); |
| 240 | } else if (ff->func == fetch_stack) |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 241 | ret = snprintf(buf, n, "$stack%lu", (unsigned long)ff->data); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 242 | else if (ff->func == fetch_memory) |
| 243 | ret = snprintf(buf, n, "@0x%p", ff->data); |
| 244 | else if (ff->func == fetch_symbol) { |
| 245 | struct symbol_cache *sc = ff->data; |
Lai Jiangshan | 52a11f3 | 2009-11-25 16:33:15 +0800 | [diff] [blame] | 246 | if (sc->offset) |
| 247 | ret = snprintf(buf, n, "@%s%+ld", sc->symbol, |
| 248 | sc->offset); |
| 249 | else |
| 250 | ret = snprintf(buf, n, "@%s", sc->symbol); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 251 | } else if (ff->func == fetch_retvalue) |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 252 | ret = snprintf(buf, n, "$retval"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 253 | else if (ff->func == fetch_stack_address) |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 254 | ret = snprintf(buf, n, "$stack"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 255 | else if (ff->func == fetch_indirect) { |
| 256 | struct indirect_fetch_data *id = ff->data; |
| 257 | size_t l = 0; |
| 258 | ret = snprintf(buf, n, "%+ld(", id->offset); |
| 259 | if (ret >= n) |
| 260 | goto end; |
| 261 | l += ret; |
Masami Hiramatsu | 30a7e07 | 2009-08-21 15:43:51 -0400 | [diff] [blame] | 262 | ret = probe_arg_string(buf + l, n - l, &id->orig); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 263 | if (ret < 0) |
| 264 | goto end; |
| 265 | l += ret; |
| 266 | ret = snprintf(buf + l, n - l, ")"); |
| 267 | ret += l; |
| 268 | } |
| 269 | end: |
| 270 | if (ret >= n) |
| 271 | return -ENOSPC; |
| 272 | return ret; |
| 273 | } |
| 274 | |
| 275 | static int register_probe_event(struct trace_probe *tp); |
| 276 | static void unregister_probe_event(struct trace_probe *tp); |
| 277 | |
| 278 | static DEFINE_MUTEX(probe_lock); |
| 279 | static LIST_HEAD(probe_list); |
| 280 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 281 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
| 282 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, |
| 283 | struct pt_regs *regs); |
| 284 | |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 285 | /* Check the name is good for event/group */ |
| 286 | static int check_event_name(const char *name) |
| 287 | { |
| 288 | if (!isalpha(*name) && *name != '_') |
| 289 | return 0; |
| 290 | while (*++name != '\0') { |
| 291 | if (!isalpha(*name) && !isdigit(*name) && *name != '_') |
| 292 | return 0; |
| 293 | } |
| 294 | return 1; |
| 295 | } |
| 296 | |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 297 | /* |
| 298 | * Allocate new trace_probe and initialize it (including kprobes). |
| 299 | */ |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 300 | static struct trace_probe *alloc_trace_probe(const char *group, |
| 301 | const char *event, |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 302 | void *addr, |
| 303 | const char *symbol, |
| 304 | unsigned long offs, |
| 305 | int nargs, int is_return) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 306 | { |
| 307 | struct trace_probe *tp; |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 308 | int ret = -ENOMEM; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 309 | |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 310 | tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 311 | if (!tp) |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 312 | return ERR_PTR(ret); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 313 | |
| 314 | if (symbol) { |
| 315 | tp->symbol = kstrdup(symbol, GFP_KERNEL); |
| 316 | if (!tp->symbol) |
| 317 | goto error; |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 318 | tp->rp.kp.symbol_name = tp->symbol; |
| 319 | tp->rp.kp.offset = offs; |
| 320 | } else |
| 321 | tp->rp.kp.addr = addr; |
| 322 | |
| 323 | if (is_return) |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 324 | tp->rp.handler = kretprobe_dispatcher; |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 325 | else |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 326 | tp->rp.kp.pre_handler = kprobe_dispatcher; |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 327 | |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 328 | if (!event || !check_event_name(event)) { |
| 329 | ret = -EINVAL; |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 330 | goto error; |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 331 | } |
| 332 | |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 333 | tp->call.name = kstrdup(event, GFP_KERNEL); |
| 334 | if (!tp->call.name) |
| 335 | goto error; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 336 | |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 337 | if (!group || !check_event_name(group)) { |
| 338 | ret = -EINVAL; |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 339 | goto error; |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 340 | } |
| 341 | |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 342 | tp->call.system = kstrdup(group, GFP_KERNEL); |
| 343 | if (!tp->call.system) |
| 344 | goto error; |
| 345 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 346 | INIT_LIST_HEAD(&tp->list); |
| 347 | return tp; |
| 348 | error: |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 349 | kfree(tp->call.name); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 350 | kfree(tp->symbol); |
| 351 | kfree(tp); |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 352 | return ERR_PTR(ret); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 353 | } |
| 354 | |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 355 | static void free_probe_arg(struct probe_arg *arg) |
| 356 | { |
| 357 | if (arg->fetch.func == fetch_symbol) |
| 358 | free_symbol_cache(arg->fetch.data); |
| 359 | else if (arg->fetch.func == fetch_indirect) |
| 360 | free_indirect_fetch_data(arg->fetch.data); |
| 361 | kfree(arg->name); |
| 362 | } |
| 363 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 364 | static void free_trace_probe(struct trace_probe *tp) |
| 365 | { |
| 366 | int i; |
| 367 | |
| 368 | for (i = 0; i < tp->nr_args; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 369 | free_probe_arg(&tp->args[i]); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 370 | |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 371 | kfree(tp->call.system); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 372 | kfree(tp->call.name); |
| 373 | kfree(tp->symbol); |
| 374 | kfree(tp); |
| 375 | } |
| 376 | |
Masami Hiramatsu | dd004c4 | 2009-10-27 16:42:44 -0400 | [diff] [blame] | 377 | static struct trace_probe *find_probe_event(const char *event, |
| 378 | const char *group) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 379 | { |
| 380 | struct trace_probe *tp; |
| 381 | |
| 382 | list_for_each_entry(tp, &probe_list, list) |
Masami Hiramatsu | dd004c4 | 2009-10-27 16:42:44 -0400 | [diff] [blame] | 383 | if (strcmp(tp->call.name, event) == 0 && |
| 384 | strcmp(tp->call.system, group) == 0) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 385 | return tp; |
| 386 | return NULL; |
| 387 | } |
| 388 | |
Masami Hiramatsu | 2d5e067 | 2009-09-14 16:48:56 -0400 | [diff] [blame] | 389 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ |
| 390 | static void unregister_trace_probe(struct trace_probe *tp) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 391 | { |
| 392 | if (probe_is_return(tp)) |
| 393 | unregister_kretprobe(&tp->rp); |
| 394 | else |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 395 | unregister_kprobe(&tp->rp.kp); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 396 | list_del(&tp->list); |
Masami Hiramatsu | 2d5e067 | 2009-09-14 16:48:56 -0400 | [diff] [blame] | 397 | unregister_probe_event(tp); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 398 | } |
| 399 | |
| 400 | /* Register a trace_probe and probe_event */ |
| 401 | static int register_trace_probe(struct trace_probe *tp) |
| 402 | { |
| 403 | struct trace_probe *old_tp; |
| 404 | int ret; |
| 405 | |
| 406 | mutex_lock(&probe_lock); |
| 407 | |
Masami Hiramatsu | 2d5e067 | 2009-09-14 16:48:56 -0400 | [diff] [blame] | 408 | /* register as an event */ |
Masami Hiramatsu | dd004c4 | 2009-10-27 16:42:44 -0400 | [diff] [blame] | 409 | old_tp = find_probe_event(tp->call.name, tp->call.system); |
Masami Hiramatsu | 2d5e067 | 2009-09-14 16:48:56 -0400 | [diff] [blame] | 410 | if (old_tp) { |
| 411 | /* delete old event */ |
| 412 | unregister_trace_probe(old_tp); |
| 413 | free_trace_probe(old_tp); |
| 414 | } |
| 415 | ret = register_probe_event(tp); |
| 416 | if (ret) { |
| 417 | pr_warning("Faild to register probe event(%d)\n", ret); |
| 418 | goto end; |
| 419 | } |
| 420 | |
Masami Hiramatsu | 5a0d905 | 2009-09-14 16:49:37 -0400 | [diff] [blame] | 421 | tp->rp.kp.flags |= KPROBE_FLAG_DISABLED; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 422 | if (probe_is_return(tp)) |
| 423 | ret = register_kretprobe(&tp->rp); |
| 424 | else |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 425 | ret = register_kprobe(&tp->rp.kp); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 426 | |
| 427 | if (ret) { |
| 428 | pr_warning("Could not insert probe(%d)\n", ret); |
| 429 | if (ret == -EILSEQ) { |
| 430 | pr_warning("Probing address(0x%p) is not an " |
| 431 | "instruction boundary.\n", |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 432 | tp->rp.kp.addr); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 433 | ret = -EINVAL; |
| 434 | } |
Masami Hiramatsu | 2d5e067 | 2009-09-14 16:48:56 -0400 | [diff] [blame] | 435 | unregister_probe_event(tp); |
| 436 | } else |
| 437 | list_add_tail(&tp->list, &probe_list); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 438 | end: |
| 439 | mutex_unlock(&probe_lock); |
| 440 | return ret; |
| 441 | } |
| 442 | |
| 443 | /* Split symbol and offset. */ |
Masami Hiramatsu | 2fba0c8 | 2009-09-10 19:53:14 -0400 | [diff] [blame] | 444 | static int split_symbol_offset(char *symbol, unsigned long *offset) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 445 | { |
| 446 | char *tmp; |
| 447 | int ret; |
| 448 | |
| 449 | if (!offset) |
| 450 | return -EINVAL; |
| 451 | |
| 452 | tmp = strchr(symbol, '+'); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 453 | if (tmp) { |
| 454 | /* skip sign because strict_strtol doesn't accept '+' */ |
Masami Hiramatsu | 2fba0c8 | 2009-09-10 19:53:14 -0400 | [diff] [blame] | 455 | ret = strict_strtoul(tmp + 1, 0, offset); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 456 | if (ret) |
| 457 | return ret; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 458 | *tmp = '\0'; |
| 459 | } else |
| 460 | *offset = 0; |
| 461 | return 0; |
| 462 | } |
| 463 | |
| 464 | #define PARAM_MAX_ARGS 16 |
| 465 | #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) |
| 466 | |
Masami Hiramatsu | 405b265 | 2009-10-07 18:27:40 -0400 | [diff] [blame] | 467 | static int parse_probe_vars(char *arg, struct fetch_func *ff, int is_return) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 468 | { |
| 469 | int ret = 0; |
| 470 | unsigned long param; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 471 | |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 472 | if (strcmp(arg, "retval") == 0) { |
| 473 | if (is_return) { |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 474 | ff->func = fetch_retvalue; |
| 475 | ff->data = NULL; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 476 | } else |
| 477 | ret = -EINVAL; |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 478 | } else if (strncmp(arg, "stack", 5) == 0) { |
| 479 | if (arg[5] == '\0') { |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 480 | ff->func = fetch_stack_address; |
| 481 | ff->data = NULL; |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 482 | } else if (isdigit(arg[5])) { |
| 483 | ret = strict_strtoul(arg + 5, 10, ¶m); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 484 | if (ret || param > PARAM_MAX_STACK) |
| 485 | ret = -EINVAL; |
| 486 | else { |
| 487 | ff->func = fetch_stack; |
| 488 | ff->data = (void *)param; |
| 489 | } |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 490 | } else |
| 491 | ret = -EINVAL; |
| 492 | } else if (strncmp(arg, "arg", 3) == 0 && isdigit(arg[3])) { |
| 493 | ret = strict_strtoul(arg + 3, 10, ¶m); |
| 494 | if (ret || param > PARAM_MAX_ARGS) |
| 495 | ret = -EINVAL; |
| 496 | else { |
| 497 | ff->func = fetch_argument; |
| 498 | ff->data = (void *)param; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 499 | } |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 500 | } else |
Masami Hiramatsu | 405b265 | 2009-10-07 18:27:40 -0400 | [diff] [blame] | 501 | ret = -EINVAL; |
Masami Hiramatsu | 405b265 | 2009-10-07 18:27:40 -0400 | [diff] [blame] | 502 | return ret; |
| 503 | } |
| 504 | |
Masami Hiramatsu | ba8665d | 2009-11-30 19:19:20 -0500 | [diff] [blame] | 505 | /* Recursive argument parser */ |
| 506 | static int __parse_probe_arg(char *arg, struct fetch_func *ff, int is_return) |
Masami Hiramatsu | 405b265 | 2009-10-07 18:27:40 -0400 | [diff] [blame] | 507 | { |
| 508 | int ret = 0; |
| 509 | unsigned long param; |
| 510 | long offset; |
| 511 | char *tmp; |
| 512 | |
| 513 | switch (arg[0]) { |
| 514 | case '$': |
| 515 | ret = parse_probe_vars(arg + 1, ff, is_return); |
| 516 | break; |
| 517 | case '%': /* named register */ |
| 518 | ret = regs_query_register_offset(arg + 1); |
| 519 | if (ret >= 0) { |
| 520 | ff->func = fetch_register; |
| 521 | ff->data = (void *)(unsigned long)ret; |
| 522 | ret = 0; |
| 523 | } |
| 524 | break; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 525 | case '@': /* memory or symbol */ |
| 526 | if (isdigit(arg[1])) { |
| 527 | ret = strict_strtoul(arg + 1, 0, ¶m); |
| 528 | if (ret) |
| 529 | break; |
| 530 | ff->func = fetch_memory; |
| 531 | ff->data = (void *)param; |
| 532 | } else { |
| 533 | ret = split_symbol_offset(arg + 1, &offset); |
| 534 | if (ret) |
| 535 | break; |
Masami Hiramatsu | 405b265 | 2009-10-07 18:27:40 -0400 | [diff] [blame] | 536 | ff->data = alloc_symbol_cache(arg + 1, offset); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 537 | if (ff->data) |
| 538 | ff->func = fetch_symbol; |
| 539 | else |
| 540 | ret = -EINVAL; |
| 541 | } |
| 542 | break; |
| 543 | case '+': /* indirect memory */ |
| 544 | case '-': |
| 545 | tmp = strchr(arg, '('); |
| 546 | if (!tmp) { |
| 547 | ret = -EINVAL; |
| 548 | break; |
| 549 | } |
| 550 | *tmp = '\0'; |
| 551 | ret = strict_strtol(arg + 1, 0, &offset); |
| 552 | if (ret) |
| 553 | break; |
| 554 | if (arg[0] == '-') |
| 555 | offset = -offset; |
| 556 | arg = tmp + 1; |
| 557 | tmp = strrchr(arg, ')'); |
| 558 | if (tmp) { |
| 559 | struct indirect_fetch_data *id; |
| 560 | *tmp = '\0'; |
| 561 | id = kzalloc(sizeof(struct indirect_fetch_data), |
| 562 | GFP_KERNEL); |
| 563 | if (!id) |
| 564 | return -ENOMEM; |
| 565 | id->offset = offset; |
Masami Hiramatsu | ba8665d | 2009-11-30 19:19:20 -0500 | [diff] [blame] | 566 | ret = __parse_probe_arg(arg, &id->orig, is_return); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 567 | if (ret) |
| 568 | kfree(id); |
| 569 | else { |
| 570 | ff->func = fetch_indirect; |
| 571 | ff->data = (void *)id; |
| 572 | } |
| 573 | } else |
| 574 | ret = -EINVAL; |
| 575 | break; |
| 576 | default: |
| 577 | /* TODO: support custom handler */ |
| 578 | ret = -EINVAL; |
| 579 | } |
| 580 | return ret; |
| 581 | } |
| 582 | |
Masami Hiramatsu | ba8665d | 2009-11-30 19:19:20 -0500 | [diff] [blame] | 583 | /* String length checking wrapper */ |
| 584 | static int parse_probe_arg(char *arg, struct fetch_func *ff, int is_return) |
| 585 | { |
| 586 | if (strlen(arg) > MAX_ARGSTR_LEN) { |
| 587 | pr_info("Argument is too long.: %s\n", arg); |
| 588 | return -ENOSPC; |
| 589 | } |
| 590 | return __parse_probe_arg(arg, ff, is_return); |
| 591 | } |
| 592 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 593 | /* Return 1 if name is reserved or already used by another argument */ |
| 594 | static int conflict_field_name(const char *name, |
| 595 | struct probe_arg *args, int narg) |
| 596 | { |
| 597 | int i; |
| 598 | for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) |
| 599 | if (strcmp(reserved_field_names[i], name) == 0) |
| 600 | return 1; |
| 601 | for (i = 0; i < narg; i++) |
| 602 | if (strcmp(args[i].name, name) == 0) |
| 603 | return 1; |
| 604 | return 0; |
| 605 | } |
| 606 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 607 | static int create_trace_probe(int argc, char **argv) |
| 608 | { |
| 609 | /* |
| 610 | * Argument syntax: |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 611 | * - Add kprobe: p[:[GRP/]EVENT] KSYM[+OFFS]|KADDR [FETCHARGS] |
| 612 | * - Add kretprobe: r[:[GRP/]EVENT] KSYM[+0] [FETCHARGS] |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 613 | * Fetch args: |
Masami Hiramatsu | 2e06ff6 | 2009-10-07 18:27:59 -0400 | [diff] [blame] | 614 | * $argN : fetch Nth of function argument. (N:0-) |
| 615 | * $retval : fetch return value |
| 616 | * $stack : fetch stack address |
| 617 | * $stackN : fetch Nth of stack (N:0-) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 618 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
| 619 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) |
| 620 | * %REG : fetch register REG |
| 621 | * Indirect memory fetch: |
| 622 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 623 | * Alias name of args: |
| 624 | * NAME=FETCHARG : set NAME as alias of FETCHARG. |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 625 | */ |
| 626 | struct trace_probe *tp; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 627 | int i, ret = 0; |
Masami Hiramatsu | a7c312b | 2009-12-08 17:03:16 -0500 | [diff] [blame] | 628 | int is_return = 0, is_delete = 0; |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 629 | char *symbol = NULL, *event = NULL, *arg = NULL, *group = NULL; |
Masami Hiramatsu | 2fba0c8 | 2009-09-10 19:53:14 -0400 | [diff] [blame] | 630 | unsigned long offset = 0; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 631 | void *addr = NULL; |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 632 | char buf[MAX_EVENT_NAME_LEN]; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 633 | |
Masami Hiramatsu | a7c312b | 2009-12-08 17:03:16 -0500 | [diff] [blame] | 634 | /* argc must be >= 1 */ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 635 | if (argv[0][0] == 'p') |
| 636 | is_return = 0; |
| 637 | else if (argv[0][0] == 'r') |
| 638 | is_return = 1; |
Masami Hiramatsu | a7c312b | 2009-12-08 17:03:16 -0500 | [diff] [blame] | 639 | else if (argv[0][0] == '-') |
| 640 | is_delete = 1; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 641 | else { |
Masami Hiramatsu | a7c312b | 2009-12-08 17:03:16 -0500 | [diff] [blame] | 642 | pr_info("Probe definition must be started with 'p', 'r' or" |
| 643 | " '-'.\n"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 644 | return -EINVAL; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 645 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 646 | |
| 647 | if (argv[0][1] == ':') { |
| 648 | event = &argv[0][2]; |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 649 | if (strchr(event, '/')) { |
| 650 | group = event; |
| 651 | event = strchr(group, '/') + 1; |
| 652 | event[-1] = '\0'; |
| 653 | if (strlen(group) == 0) { |
| 654 | pr_info("Group name is not specifiled\n"); |
| 655 | return -EINVAL; |
| 656 | } |
| 657 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 658 | if (strlen(event) == 0) { |
| 659 | pr_info("Event name is not specifiled\n"); |
| 660 | return -EINVAL; |
| 661 | } |
| 662 | } |
Masami Hiramatsu | a7c312b | 2009-12-08 17:03:16 -0500 | [diff] [blame] | 663 | if (!group) |
| 664 | group = KPROBE_EVENT_SYSTEM; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 665 | |
Masami Hiramatsu | a7c312b | 2009-12-08 17:03:16 -0500 | [diff] [blame] | 666 | if (is_delete) { |
| 667 | if (!event) { |
| 668 | pr_info("Delete command needs an event name.\n"); |
| 669 | return -EINVAL; |
| 670 | } |
| 671 | tp = find_probe_event(event, group); |
| 672 | if (!tp) { |
| 673 | pr_info("Event %s/%s doesn't exist.\n", group, event); |
| 674 | return -ENOENT; |
| 675 | } |
| 676 | /* delete an event */ |
| 677 | unregister_trace_probe(tp); |
| 678 | free_trace_probe(tp); |
| 679 | return 0; |
| 680 | } |
| 681 | |
| 682 | if (argc < 2) { |
| 683 | pr_info("Probe point is not specified.\n"); |
| 684 | return -EINVAL; |
| 685 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 686 | if (isdigit(argv[1][0])) { |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 687 | if (is_return) { |
| 688 | pr_info("Return probe point must be a symbol.\n"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 689 | return -EINVAL; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 690 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 691 | /* an address specified */ |
| 692 | ret = strict_strtoul(&argv[0][2], 0, (unsigned long *)&addr); |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 693 | if (ret) { |
| 694 | pr_info("Failed to parse address.\n"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 695 | return ret; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 696 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 697 | } else { |
| 698 | /* a symbol specified */ |
| 699 | symbol = argv[1]; |
| 700 | /* TODO: support .init module functions */ |
| 701 | ret = split_symbol_offset(symbol, &offset); |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 702 | if (ret) { |
| 703 | pr_info("Failed to parse symbol.\n"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 704 | return ret; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 705 | } |
| 706 | if (offset && is_return) { |
| 707 | pr_info("Return probe must be used without offset.\n"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 708 | return -EINVAL; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 709 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 710 | } |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 711 | argc -= 2; argv += 2; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 712 | |
| 713 | /* setup a probe */ |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 714 | if (!event) { |
| 715 | /* Make a new event name */ |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 716 | if (symbol) |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 717 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 718 | is_return ? 'r' : 'p', symbol, offset); |
| 719 | else |
Masami Hiramatsu | 6f3cf44 | 2009-12-16 17:24:08 -0500 | [diff] [blame] | 720 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 721 | is_return ? 'r' : 'p', addr); |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 722 | event = buf; |
| 723 | } |
Masami Hiramatsu | f52487e | 2009-09-10 19:53:53 -0400 | [diff] [blame] | 724 | tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, |
| 725 | is_return); |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 726 | if (IS_ERR(tp)) { |
| 727 | pr_info("Failed to allocate trace_probe.(%d)\n", |
| 728 | (int)PTR_ERR(tp)); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 729 | return PTR_ERR(tp); |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 730 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 731 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 732 | /* parse arguments */ |
Masami Hiramatsu | a82378d | 2009-08-13 16:35:18 -0400 | [diff] [blame] | 733 | ret = 0; |
| 734 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 735 | /* Parse argument name */ |
| 736 | arg = strchr(argv[i], '='); |
| 737 | if (arg) |
| 738 | *arg++ = '\0'; |
| 739 | else |
| 740 | arg = argv[i]; |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 741 | |
| 742 | if (conflict_field_name(argv[i], tp->args, i)) { |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 743 | pr_info("Argument%d name '%s' conflicts with " |
| 744 | "another field.\n", i, argv[i]); |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 745 | ret = -EINVAL; |
| 746 | goto error; |
| 747 | } |
| 748 | |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 749 | tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); |
Masami Hiramatsu | ba8665d | 2009-11-30 19:19:20 -0500 | [diff] [blame] | 750 | if (!tp->args[i].name) { |
| 751 | pr_info("Failed to allocate argument%d name '%s'.\n", |
| 752 | i, argv[i]); |
| 753 | ret = -ENOMEM; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 754 | goto error; |
| 755 | } |
Masami Hiramatsu | ba8665d | 2009-11-30 19:19:20 -0500 | [diff] [blame] | 756 | |
| 757 | /* Parse fetch argument */ |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 758 | ret = parse_probe_arg(arg, &tp->args[i].fetch, is_return); |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 759 | if (ret) { |
| 760 | pr_info("Parse error at argument%d. (%d)\n", i, ret); |
Lai Jiangshan | abab9d3 | 2009-11-25 16:32:21 +0800 | [diff] [blame] | 761 | kfree(tp->args[i].name); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 762 | goto error; |
Masami Hiramatsu | e63cc23 | 2009-10-16 20:07:28 -0400 | [diff] [blame] | 763 | } |
Lai Jiangshan | abab9d3 | 2009-11-25 16:32:21 +0800 | [diff] [blame] | 764 | |
| 765 | tp->nr_args++; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 766 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 767 | |
| 768 | ret = register_trace_probe(tp); |
| 769 | if (ret) |
| 770 | goto error; |
| 771 | return 0; |
| 772 | |
| 773 | error: |
| 774 | free_trace_probe(tp); |
| 775 | return ret; |
| 776 | } |
| 777 | |
| 778 | static void cleanup_all_probes(void) |
| 779 | { |
| 780 | struct trace_probe *tp; |
| 781 | |
| 782 | mutex_lock(&probe_lock); |
| 783 | /* TODO: Use batch unregistration */ |
| 784 | while (!list_empty(&probe_list)) { |
| 785 | tp = list_entry(probe_list.next, struct trace_probe, list); |
| 786 | unregister_trace_probe(tp); |
| 787 | free_trace_probe(tp); |
| 788 | } |
| 789 | mutex_unlock(&probe_lock); |
| 790 | } |
| 791 | |
| 792 | |
| 793 | /* Probes listing interfaces */ |
| 794 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) |
| 795 | { |
| 796 | mutex_lock(&probe_lock); |
| 797 | return seq_list_start(&probe_list, *pos); |
| 798 | } |
| 799 | |
| 800 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) |
| 801 | { |
| 802 | return seq_list_next(v, &probe_list, pos); |
| 803 | } |
| 804 | |
| 805 | static void probes_seq_stop(struct seq_file *m, void *v) |
| 806 | { |
| 807 | mutex_unlock(&probe_lock); |
| 808 | } |
| 809 | |
| 810 | static int probes_seq_show(struct seq_file *m, void *v) |
| 811 | { |
| 812 | struct trace_probe *tp = v; |
| 813 | int i, ret; |
| 814 | char buf[MAX_ARGSTR_LEN + 1]; |
| 815 | |
| 816 | seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p'); |
Lai Jiangshan | 3d9b2e1 | 2009-11-25 16:32:47 +0800 | [diff] [blame] | 817 | seq_printf(m, ":%s/%s", tp->call.system, tp->call.name); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 818 | |
Lai Jiangshan | 52a11f3 | 2009-11-25 16:33:15 +0800 | [diff] [blame] | 819 | if (!tp->symbol) |
| 820 | seq_printf(m, " 0x%p", tp->rp.kp.addr); |
| 821 | else if (tp->rp.kp.offset) |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 822 | seq_printf(m, " %s+%u", probe_symbol(tp), tp->rp.kp.offset); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 823 | else |
Lai Jiangshan | 52a11f3 | 2009-11-25 16:33:15 +0800 | [diff] [blame] | 824 | seq_printf(m, " %s", probe_symbol(tp)); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 825 | |
| 826 | for (i = 0; i < tp->nr_args; i++) { |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 827 | ret = probe_arg_string(buf, MAX_ARGSTR_LEN, &tp->args[i].fetch); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 828 | if (ret < 0) { |
| 829 | pr_warning("Argument%d decoding error(%d).\n", i, ret); |
| 830 | return ret; |
| 831 | } |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 832 | seq_printf(m, " %s=%s", tp->args[i].name, buf); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 833 | } |
| 834 | seq_printf(m, "\n"); |
| 835 | return 0; |
| 836 | } |
| 837 | |
| 838 | static const struct seq_operations probes_seq_op = { |
| 839 | .start = probes_seq_start, |
| 840 | .next = probes_seq_next, |
| 841 | .stop = probes_seq_stop, |
| 842 | .show = probes_seq_show |
| 843 | }; |
| 844 | |
| 845 | static int probes_open(struct inode *inode, struct file *file) |
| 846 | { |
| 847 | if ((file->f_mode & FMODE_WRITE) && |
| 848 | (file->f_flags & O_TRUNC)) |
| 849 | cleanup_all_probes(); |
| 850 | |
| 851 | return seq_open(file, &probes_seq_op); |
| 852 | } |
| 853 | |
| 854 | static int command_trace_probe(const char *buf) |
| 855 | { |
| 856 | char **argv; |
| 857 | int argc = 0, ret = 0; |
| 858 | |
| 859 | argv = argv_split(GFP_KERNEL, buf, &argc); |
| 860 | if (!argv) |
| 861 | return -ENOMEM; |
| 862 | |
| 863 | if (argc) |
| 864 | ret = create_trace_probe(argc, argv); |
| 865 | |
| 866 | argv_free(argv); |
| 867 | return ret; |
| 868 | } |
| 869 | |
| 870 | #define WRITE_BUFSIZE 128 |
| 871 | |
| 872 | static ssize_t probes_write(struct file *file, const char __user *buffer, |
| 873 | size_t count, loff_t *ppos) |
| 874 | { |
| 875 | char *kbuf, *tmp; |
| 876 | int ret; |
| 877 | size_t done; |
| 878 | size_t size; |
| 879 | |
| 880 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); |
| 881 | if (!kbuf) |
| 882 | return -ENOMEM; |
| 883 | |
| 884 | ret = done = 0; |
| 885 | while (done < count) { |
| 886 | size = count - done; |
| 887 | if (size >= WRITE_BUFSIZE) |
| 888 | size = WRITE_BUFSIZE - 1; |
| 889 | if (copy_from_user(kbuf, buffer + done, size)) { |
| 890 | ret = -EFAULT; |
| 891 | goto out; |
| 892 | } |
| 893 | kbuf[size] = '\0'; |
| 894 | tmp = strchr(kbuf, '\n'); |
| 895 | if (tmp) { |
| 896 | *tmp = '\0'; |
| 897 | size = tmp - kbuf + 1; |
| 898 | } else if (done + size < count) { |
| 899 | pr_warning("Line length is too long: " |
| 900 | "Should be less than %d.", WRITE_BUFSIZE); |
| 901 | ret = -EINVAL; |
| 902 | goto out; |
| 903 | } |
| 904 | done += size; |
| 905 | /* Remove comments */ |
| 906 | tmp = strchr(kbuf, '#'); |
| 907 | if (tmp) |
| 908 | *tmp = '\0'; |
| 909 | |
| 910 | ret = command_trace_probe(kbuf); |
| 911 | if (ret) |
| 912 | goto out; |
| 913 | } |
| 914 | ret = done; |
| 915 | out: |
| 916 | kfree(kbuf); |
| 917 | return ret; |
| 918 | } |
| 919 | |
| 920 | static const struct file_operations kprobe_events_ops = { |
| 921 | .owner = THIS_MODULE, |
| 922 | .open = probes_open, |
| 923 | .read = seq_read, |
| 924 | .llseek = seq_lseek, |
| 925 | .release = seq_release, |
| 926 | .write = probes_write, |
| 927 | }; |
| 928 | |
Masami Hiramatsu | cd7e7bd | 2009-08-13 16:35:42 -0400 | [diff] [blame] | 929 | /* Probes profiling interfaces */ |
| 930 | static int probes_profile_seq_show(struct seq_file *m, void *v) |
| 931 | { |
| 932 | struct trace_probe *tp = v; |
| 933 | |
| 934 | seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 935 | tp->rp.kp.nmissed); |
Masami Hiramatsu | cd7e7bd | 2009-08-13 16:35:42 -0400 | [diff] [blame] | 936 | |
| 937 | return 0; |
| 938 | } |
| 939 | |
| 940 | static const struct seq_operations profile_seq_op = { |
| 941 | .start = probes_seq_start, |
| 942 | .next = probes_seq_next, |
| 943 | .stop = probes_seq_stop, |
| 944 | .show = probes_profile_seq_show |
| 945 | }; |
| 946 | |
| 947 | static int profile_open(struct inode *inode, struct file *file) |
| 948 | { |
| 949 | return seq_open(file, &profile_seq_op); |
| 950 | } |
| 951 | |
| 952 | static const struct file_operations kprobe_profile_ops = { |
| 953 | .owner = THIS_MODULE, |
| 954 | .open = profile_open, |
| 955 | .read = seq_read, |
| 956 | .llseek = seq_lseek, |
| 957 | .release = seq_release, |
| 958 | }; |
| 959 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 960 | /* Kprobe handler */ |
| 961 | static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) |
| 962 | { |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 963 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 964 | struct kprobe_trace_entry *entry; |
| 965 | struct ring_buffer_event *event; |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 966 | struct ring_buffer *buffer; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 967 | int size, i, pc; |
| 968 | unsigned long irq_flags; |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 969 | struct ftrace_event_call *call = &tp->call; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 970 | |
Masami Hiramatsu | cd7e7bd | 2009-08-13 16:35:42 -0400 | [diff] [blame] | 971 | tp->nhit++; |
| 972 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 973 | local_save_flags(irq_flags); |
| 974 | pc = preempt_count(); |
| 975 | |
| 976 | size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args); |
| 977 | |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 978 | event = trace_current_buffer_lock_reserve(&buffer, call->id, size, |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 979 | irq_flags, pc); |
| 980 | if (!event) |
| 981 | return 0; |
| 982 | |
| 983 | entry = ring_buffer_event_data(event); |
| 984 | entry->nargs = tp->nr_args; |
| 985 | entry->ip = (unsigned long)kp->addr; |
| 986 | for (i = 0; i < tp->nr_args; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 987 | entry->args[i] = call_fetch(&tp->args[i].fetch, regs); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 988 | |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 989 | if (!filter_current_check_discard(buffer, call, entry, event)) |
| 990 | trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 991 | return 0; |
| 992 | } |
| 993 | |
| 994 | /* Kretprobe handler */ |
| 995 | static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri, |
| 996 | struct pt_regs *regs) |
| 997 | { |
| 998 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); |
| 999 | struct kretprobe_trace_entry *entry; |
| 1000 | struct ring_buffer_event *event; |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 1001 | struct ring_buffer *buffer; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1002 | int size, i, pc; |
| 1003 | unsigned long irq_flags; |
Masami Hiramatsu | 4263565 | 2009-08-13 16:35:26 -0400 | [diff] [blame] | 1004 | struct ftrace_event_call *call = &tp->call; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1005 | |
| 1006 | local_save_flags(irq_flags); |
| 1007 | pc = preempt_count(); |
| 1008 | |
| 1009 | size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args); |
| 1010 | |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 1011 | event = trace_current_buffer_lock_reserve(&buffer, call->id, size, |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1012 | irq_flags, pc); |
| 1013 | if (!event) |
| 1014 | return 0; |
| 1015 | |
| 1016 | entry = ring_buffer_event_data(event); |
| 1017 | entry->nargs = tp->nr_args; |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 1018 | entry->func = (unsigned long)tp->rp.kp.addr; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1019 | entry->ret_ip = (unsigned long)ri->ret_addr; |
| 1020 | for (i = 0; i < tp->nr_args; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1021 | entry->args[i] = call_fetch(&tp->args[i].fetch, regs); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1022 | |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 1023 | if (!filter_current_check_discard(buffer, call, entry, event)) |
| 1024 | trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1025 | |
| 1026 | return 0; |
| 1027 | } |
| 1028 | |
| 1029 | /* Event entry printers */ |
| 1030 | enum print_line_t |
| 1031 | print_kprobe_event(struct trace_iterator *iter, int flags) |
| 1032 | { |
| 1033 | struct kprobe_trace_entry *field; |
| 1034 | struct trace_seq *s = &iter->seq; |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1035 | struct trace_event *event; |
| 1036 | struct trace_probe *tp; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1037 | int i; |
| 1038 | |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1039 | field = (struct kprobe_trace_entry *)iter->ent; |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1040 | event = ftrace_find_event(field->ent.type); |
| 1041 | tp = container_of(event, struct trace_probe, event); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1042 | |
Masami Hiramatsu | 6e9f23d | 2009-09-10 19:53:45 -0400 | [diff] [blame] | 1043 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
| 1044 | goto partial; |
| 1045 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1046 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
| 1047 | goto partial; |
| 1048 | |
Masami Hiramatsu | 6e9f23d | 2009-09-10 19:53:45 -0400 | [diff] [blame] | 1049 | if (!trace_seq_puts(s, ")")) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1050 | goto partial; |
| 1051 | |
| 1052 | for (i = 0; i < field->nargs; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1053 | if (!trace_seq_printf(s, " %s=%lx", |
| 1054 | tp->args[i].name, field->args[i])) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1055 | goto partial; |
| 1056 | |
| 1057 | if (!trace_seq_puts(s, "\n")) |
| 1058 | goto partial; |
| 1059 | |
| 1060 | return TRACE_TYPE_HANDLED; |
| 1061 | partial: |
| 1062 | return TRACE_TYPE_PARTIAL_LINE; |
| 1063 | } |
| 1064 | |
| 1065 | enum print_line_t |
| 1066 | print_kretprobe_event(struct trace_iterator *iter, int flags) |
| 1067 | { |
| 1068 | struct kretprobe_trace_entry *field; |
| 1069 | struct trace_seq *s = &iter->seq; |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1070 | struct trace_event *event; |
| 1071 | struct trace_probe *tp; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1072 | int i; |
| 1073 | |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1074 | field = (struct kretprobe_trace_entry *)iter->ent; |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1075 | event = ftrace_find_event(field->ent.type); |
| 1076 | tp = container_of(event, struct trace_probe, event); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1077 | |
Masami Hiramatsu | 6e9f23d | 2009-09-10 19:53:45 -0400 | [diff] [blame] | 1078 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
| 1079 | goto partial; |
| 1080 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1081 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
| 1082 | goto partial; |
| 1083 | |
| 1084 | if (!trace_seq_puts(s, " <- ")) |
| 1085 | goto partial; |
| 1086 | |
| 1087 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) |
| 1088 | goto partial; |
| 1089 | |
Masami Hiramatsu | 6e9f23d | 2009-09-10 19:53:45 -0400 | [diff] [blame] | 1090 | if (!trace_seq_puts(s, ")")) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1091 | goto partial; |
| 1092 | |
| 1093 | for (i = 0; i < field->nargs; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1094 | if (!trace_seq_printf(s, " %s=%lx", |
| 1095 | tp->args[i].name, field->args[i])) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1096 | goto partial; |
| 1097 | |
| 1098 | if (!trace_seq_puts(s, "\n")) |
| 1099 | goto partial; |
| 1100 | |
| 1101 | return TRACE_TYPE_HANDLED; |
| 1102 | partial: |
| 1103 | return TRACE_TYPE_PARTIAL_LINE; |
| 1104 | } |
| 1105 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1106 | static int probe_event_enable(struct ftrace_event_call *call) |
| 1107 | { |
| 1108 | struct trace_probe *tp = (struct trace_probe *)call->data; |
| 1109 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1110 | tp->flags |= TP_FLAG_TRACE; |
| 1111 | if (probe_is_return(tp)) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1112 | return enable_kretprobe(&tp->rp); |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1113 | else |
Masami Hiramatsu | 4a846b4 | 2009-09-11 05:31:21 +0200 | [diff] [blame] | 1114 | return enable_kprobe(&tp->rp.kp); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1115 | } |
| 1116 | |
| 1117 | static void probe_event_disable(struct ftrace_event_call *call) |
| 1118 | { |
| 1119 | struct trace_probe *tp = (struct trace_probe *)call->data; |
| 1120 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1121 | tp->flags &= ~TP_FLAG_TRACE; |
| 1122 | if (!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE))) { |
| 1123 | if (probe_is_return(tp)) |
| 1124 | disable_kretprobe(&tp->rp); |
| 1125 | else |
| 1126 | disable_kprobe(&tp->rp.kp); |
| 1127 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1128 | } |
| 1129 | |
| 1130 | static int probe_event_raw_init(struct ftrace_event_call *event_call) |
| 1131 | { |
| 1132 | INIT_LIST_HEAD(&event_call->fields); |
Frederic Weisbecker | 8f8ffe2 | 2009-09-11 01:09:23 +0200 | [diff] [blame] | 1133 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1134 | return 0; |
| 1135 | } |
| 1136 | |
| 1137 | #undef DEFINE_FIELD |
| 1138 | #define DEFINE_FIELD(type, item, name, is_signed) \ |
| 1139 | do { \ |
| 1140 | ret = trace_define_field(event_call, #type, name, \ |
| 1141 | offsetof(typeof(field), item), \ |
| 1142 | sizeof(field.item), is_signed, \ |
| 1143 | FILTER_OTHER); \ |
| 1144 | if (ret) \ |
| 1145 | return ret; \ |
| 1146 | } while (0) |
| 1147 | |
| 1148 | static int kprobe_event_define_fields(struct ftrace_event_call *event_call) |
| 1149 | { |
| 1150 | int ret, i; |
| 1151 | struct kprobe_trace_entry field; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1152 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
| 1153 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 1154 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
| 1155 | DEFINE_FIELD(int, nargs, FIELD_STRING_NARGS, 1); |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1156 | /* Set argument names as fields */ |
| 1157 | for (i = 0; i < tp->nr_args; i++) |
| 1158 | DEFINE_FIELD(unsigned long, args[i], tp->args[i].name, 0); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1159 | return 0; |
| 1160 | } |
| 1161 | |
| 1162 | static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) |
| 1163 | { |
| 1164 | int ret, i; |
| 1165 | struct kretprobe_trace_entry field; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1166 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
| 1167 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 1168 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
| 1169 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); |
| 1170 | DEFINE_FIELD(int, nargs, FIELD_STRING_NARGS, 1); |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1171 | /* Set argument names as fields */ |
| 1172 | for (i = 0; i < tp->nr_args; i++) |
| 1173 | DEFINE_FIELD(unsigned long, args[i], tp->args[i].name, 0); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1174 | return 0; |
| 1175 | } |
| 1176 | |
| 1177 | static int __probe_event_show_format(struct trace_seq *s, |
| 1178 | struct trace_probe *tp, const char *fmt, |
| 1179 | const char *arg) |
| 1180 | { |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1181 | int i; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1182 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1183 | /* Show format */ |
| 1184 | if (!trace_seq_printf(s, "\nprint fmt: \"%s", fmt)) |
| 1185 | return 0; |
| 1186 | |
| 1187 | for (i = 0; i < tp->nr_args; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1188 | if (!trace_seq_printf(s, " %s=%%lx", tp->args[i].name)) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1189 | return 0; |
| 1190 | |
| 1191 | if (!trace_seq_printf(s, "\", %s", arg)) |
| 1192 | return 0; |
| 1193 | |
| 1194 | for (i = 0; i < tp->nr_args; i++) |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1195 | if (!trace_seq_printf(s, ", REC->%s", tp->args[i].name)) |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1196 | return 0; |
| 1197 | |
| 1198 | return trace_seq_puts(s, "\n"); |
| 1199 | } |
| 1200 | |
| 1201 | #undef SHOW_FIELD |
| 1202 | #define SHOW_FIELD(type, item, name) \ |
| 1203 | do { \ |
Lai Jiangshan | 79b4082 | 2009-12-15 15:39:19 +0800 | [diff] [blame] | 1204 | ret = trace_seq_printf(s, "\tfield:" #type " %s;\t" \ |
| 1205 | "offset:%u;\tsize:%u;\tsigned:%d;\n", name,\ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1206 | (unsigned int)offsetof(typeof(field), item),\ |
Lai Jiangshan | 79b4082 | 2009-12-15 15:39:19 +0800 | [diff] [blame] | 1207 | (unsigned int)sizeof(type), \ |
| 1208 | is_signed_type(type)); \ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1209 | if (!ret) \ |
| 1210 | return 0; \ |
| 1211 | } while (0) |
| 1212 | |
| 1213 | static int kprobe_event_show_format(struct ftrace_event_call *call, |
| 1214 | struct trace_seq *s) |
| 1215 | { |
| 1216 | struct kprobe_trace_entry field __attribute__((unused)); |
| 1217 | int ret, i; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1218 | struct trace_probe *tp = (struct trace_probe *)call->data; |
| 1219 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 1220 | SHOW_FIELD(unsigned long, ip, FIELD_STRING_IP); |
| 1221 | SHOW_FIELD(int, nargs, FIELD_STRING_NARGS); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1222 | |
| 1223 | /* Show fields */ |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1224 | for (i = 0; i < tp->nr_args; i++) |
| 1225 | SHOW_FIELD(unsigned long, args[i], tp->args[i].name); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1226 | trace_seq_puts(s, "\n"); |
| 1227 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 1228 | return __probe_event_show_format(s, tp, "(%lx)", |
| 1229 | "REC->" FIELD_STRING_IP); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1230 | } |
| 1231 | |
| 1232 | static int kretprobe_event_show_format(struct ftrace_event_call *call, |
| 1233 | struct trace_seq *s) |
| 1234 | { |
| 1235 | struct kretprobe_trace_entry field __attribute__((unused)); |
| 1236 | int ret, i; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1237 | struct trace_probe *tp = (struct trace_probe *)call->data; |
| 1238 | |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 1239 | SHOW_FIELD(unsigned long, func, FIELD_STRING_FUNC); |
| 1240 | SHOW_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP); |
| 1241 | SHOW_FIELD(int, nargs, FIELD_STRING_NARGS); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1242 | |
| 1243 | /* Show fields */ |
Masami Hiramatsu | eca0d91 | 2009-09-10 19:53:38 -0400 | [diff] [blame] | 1244 | for (i = 0; i < tp->nr_args; i++) |
| 1245 | SHOW_FIELD(unsigned long, args[i], tp->args[i].name); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1246 | trace_seq_puts(s, "\n"); |
| 1247 | |
Masami Hiramatsu | 6e9f23d | 2009-09-10 19:53:45 -0400 | [diff] [blame] | 1248 | return __probe_event_show_format(s, tp, "(%lx <- %lx)", |
Masami Hiramatsu | a703d94 | 2009-10-07 18:28:07 -0400 | [diff] [blame] | 1249 | "REC->" FIELD_STRING_FUNC |
| 1250 | ", REC->" FIELD_STRING_RETIP); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1251 | } |
| 1252 | |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1253 | #ifdef CONFIG_EVENT_PROFILE |
| 1254 | |
| 1255 | /* Kprobe profile handler */ |
| 1256 | static __kprobes int kprobe_profile_func(struct kprobe *kp, |
| 1257 | struct pt_regs *regs) |
| 1258 | { |
| 1259 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); |
| 1260 | struct ftrace_event_call *call = &tp->call; |
| 1261 | struct kprobe_trace_entry *entry; |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1262 | struct trace_entry *ent; |
| 1263 | int size, __size, i, pc, __cpu; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1264 | unsigned long irq_flags; |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1265 | char *trace_buf; |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1266 | char *raw_data; |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 1267 | int rctx; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1268 | |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1269 | pc = preempt_count(); |
Masami Hiramatsu | 74ebb63 | 2009-09-14 16:49:28 -0400 | [diff] [blame] | 1270 | __size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args); |
| 1271 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
| 1272 | size -= sizeof(u32); |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1273 | if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, |
| 1274 | "profile buffer not large enough")) |
| 1275 | return 0; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1276 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1277 | /* |
| 1278 | * Protect the non nmi buffer |
| 1279 | * This also protects the rcu read side |
| 1280 | */ |
| 1281 | local_irq_save(irq_flags); |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1282 | |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 1283 | rctx = perf_swevent_get_recursion_context(); |
| 1284 | if (rctx < 0) |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1285 | goto end_recursion; |
| 1286 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1287 | __cpu = smp_processor_id(); |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1288 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1289 | if (in_nmi()) |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1290 | trace_buf = rcu_dereference(perf_trace_buf_nmi); |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1291 | else |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1292 | trace_buf = rcu_dereference(perf_trace_buf); |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1293 | |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1294 | if (!trace_buf) |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1295 | goto end; |
| 1296 | |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1297 | raw_data = per_cpu_ptr(trace_buf, __cpu); |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1298 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1299 | /* Zero dead bytes from alignment to avoid buffer leak to userspace */ |
| 1300 | *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; |
| 1301 | entry = (struct kprobe_trace_entry *)raw_data; |
| 1302 | ent = &entry->ent; |
| 1303 | |
| 1304 | tracing_generic_entry_update(ent, irq_flags, pc); |
| 1305 | ent->type = call->id; |
| 1306 | entry->nargs = tp->nr_args; |
| 1307 | entry->ip = (unsigned long)kp->addr; |
| 1308 | for (i = 0; i < tp->nr_args; i++) |
| 1309 | entry->args[i] = call_fetch(&tp->args[i].fetch, regs); |
| 1310 | perf_tp_event(call->id, entry->ip, 1, entry, size); |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1311 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1312 | end: |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 1313 | perf_swevent_put_recursion_context(rctx); |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1314 | end_recursion: |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1315 | local_irq_restore(irq_flags); |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1316 | |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1317 | return 0; |
| 1318 | } |
| 1319 | |
| 1320 | /* Kretprobe profile handler */ |
| 1321 | static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, |
| 1322 | struct pt_regs *regs) |
| 1323 | { |
| 1324 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); |
| 1325 | struct ftrace_event_call *call = &tp->call; |
| 1326 | struct kretprobe_trace_entry *entry; |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1327 | struct trace_entry *ent; |
| 1328 | int size, __size, i, pc, __cpu; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1329 | unsigned long irq_flags; |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1330 | char *trace_buf; |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1331 | char *raw_data; |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 1332 | int rctx; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1333 | |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1334 | pc = preempt_count(); |
Masami Hiramatsu | 74ebb63 | 2009-09-14 16:49:28 -0400 | [diff] [blame] | 1335 | __size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args); |
| 1336 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
| 1337 | size -= sizeof(u32); |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1338 | if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, |
| 1339 | "profile buffer not large enough")) |
| 1340 | return 0; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1341 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1342 | /* |
| 1343 | * Protect the non nmi buffer |
| 1344 | * This also protects the rcu read side |
| 1345 | */ |
| 1346 | local_irq_save(irq_flags); |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1347 | |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 1348 | rctx = perf_swevent_get_recursion_context(); |
| 1349 | if (rctx < 0) |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1350 | goto end_recursion; |
| 1351 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1352 | __cpu = smp_processor_id(); |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1353 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1354 | if (in_nmi()) |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1355 | trace_buf = rcu_dereference(perf_trace_buf_nmi); |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1356 | else |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1357 | trace_buf = rcu_dereference(perf_trace_buf); |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1358 | |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1359 | if (!trace_buf) |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1360 | goto end; |
| 1361 | |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1362 | raw_data = per_cpu_ptr(trace_buf, __cpu); |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1363 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1364 | /* Zero dead bytes from alignment to avoid buffer leak to userspace */ |
| 1365 | *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; |
| 1366 | entry = (struct kretprobe_trace_entry *)raw_data; |
| 1367 | ent = &entry->ent; |
| 1368 | |
| 1369 | tracing_generic_entry_update(ent, irq_flags, pc); |
| 1370 | ent->type = call->id; |
| 1371 | entry->nargs = tp->nr_args; |
| 1372 | entry->func = (unsigned long)tp->rp.kp.addr; |
| 1373 | entry->ret_ip = (unsigned long)ri->ret_addr; |
| 1374 | for (i = 0; i < tp->nr_args; i++) |
| 1375 | entry->args[i] = call_fetch(&tp->args[i].fetch, regs); |
| 1376 | perf_tp_event(call->id, entry->ret_ip, 1, entry, size); |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1377 | |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1378 | end: |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 1379 | perf_swevent_put_recursion_context(rctx); |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 1380 | end_recursion: |
Masami Hiramatsu | a1a138d | 2009-09-25 11:20:12 -0700 | [diff] [blame] | 1381 | local_irq_restore(irq_flags); |
Frederic Weisbecker | 444a2a3 | 2009-11-06 04:13:05 +0100 | [diff] [blame] | 1382 | |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1383 | return 0; |
| 1384 | } |
| 1385 | |
| 1386 | static int probe_profile_enable(struct ftrace_event_call *call) |
| 1387 | { |
| 1388 | struct trace_probe *tp = (struct trace_probe *)call->data; |
| 1389 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1390 | tp->flags |= TP_FLAG_PROFILE; |
Frederic Weisbecker | d7a4b41 | 2009-09-23 23:08:43 +0200 | [diff] [blame] | 1391 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1392 | if (probe_is_return(tp)) |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1393 | return enable_kretprobe(&tp->rp); |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1394 | else |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1395 | return enable_kprobe(&tp->rp.kp); |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1396 | } |
| 1397 | |
| 1398 | static void probe_profile_disable(struct ftrace_event_call *call) |
| 1399 | { |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1400 | struct trace_probe *tp = (struct trace_probe *)call->data; |
| 1401 | |
Frederic Weisbecker | d7a4b41 | 2009-09-23 23:08:43 +0200 | [diff] [blame] | 1402 | tp->flags &= ~TP_FLAG_PROFILE; |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1403 | |
Frederic Weisbecker | d7a4b41 | 2009-09-23 23:08:43 +0200 | [diff] [blame] | 1404 | if (!(tp->flags & TP_FLAG_TRACE)) { |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1405 | if (probe_is_return(tp)) |
| 1406 | disable_kretprobe(&tp->rp); |
| 1407 | else |
| 1408 | disable_kprobe(&tp->rp.kp); |
| 1409 | } |
| 1410 | } |
| 1411 | #endif /* CONFIG_EVENT_PROFILE */ |
| 1412 | |
| 1413 | |
| 1414 | static __kprobes |
| 1415 | int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) |
| 1416 | { |
| 1417 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); |
| 1418 | |
| 1419 | if (tp->flags & TP_FLAG_TRACE) |
| 1420 | kprobe_trace_func(kp, regs); |
| 1421 | #ifdef CONFIG_EVENT_PROFILE |
| 1422 | if (tp->flags & TP_FLAG_PROFILE) |
| 1423 | kprobe_profile_func(kp, regs); |
| 1424 | #endif /* CONFIG_EVENT_PROFILE */ |
| 1425 | return 0; /* We don't tweek kernel, so just return 0 */ |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1426 | } |
| 1427 | |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1428 | static __kprobes |
| 1429 | int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) |
| 1430 | { |
| 1431 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); |
| 1432 | |
| 1433 | if (tp->flags & TP_FLAG_TRACE) |
| 1434 | kretprobe_trace_func(ri, regs); |
| 1435 | #ifdef CONFIG_EVENT_PROFILE |
| 1436 | if (tp->flags & TP_FLAG_PROFILE) |
| 1437 | kretprobe_profile_func(ri, regs); |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1438 | #endif /* CONFIG_EVENT_PROFILE */ |
Masami Hiramatsu | 50d7805 | 2009-09-14 16:49:20 -0400 | [diff] [blame] | 1439 | return 0; /* We don't tweek kernel, so just return 0 */ |
| 1440 | } |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1441 | |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1442 | static int register_probe_event(struct trace_probe *tp) |
| 1443 | { |
| 1444 | struct ftrace_event_call *call = &tp->call; |
| 1445 | int ret; |
| 1446 | |
| 1447 | /* Initialize ftrace_event_call */ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1448 | if (probe_is_return(tp)) { |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1449 | tp->event.trace = print_kretprobe_event; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1450 | call->raw_init = probe_event_raw_init; |
| 1451 | call->show_format = kretprobe_event_show_format; |
| 1452 | call->define_fields = kretprobe_event_define_fields; |
| 1453 | } else { |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1454 | tp->event.trace = print_kprobe_event; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1455 | call->raw_init = probe_event_raw_init; |
| 1456 | call->show_format = kprobe_event_show_format; |
| 1457 | call->define_fields = kprobe_event_define_fields; |
| 1458 | } |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1459 | call->event = &tp->event; |
| 1460 | call->id = register_ftrace_event(&tp->event); |
| 1461 | if (!call->id) |
| 1462 | return -ENODEV; |
Masami Hiramatsu | 5a0d905 | 2009-09-14 16:49:37 -0400 | [diff] [blame] | 1463 | call->enabled = 0; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1464 | call->regfunc = probe_event_enable; |
| 1465 | call->unregfunc = probe_event_disable; |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1466 | |
| 1467 | #ifdef CONFIG_EVENT_PROFILE |
Masami Hiramatsu | e08d1c6 | 2009-09-10 19:53:30 -0400 | [diff] [blame] | 1468 | call->profile_enable = probe_profile_enable; |
| 1469 | call->profile_disable = probe_profile_disable; |
| 1470 | #endif |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1471 | call->data = tp; |
| 1472 | ret = trace_add_event_call(call); |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1473 | if (ret) { |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1474 | pr_info("Failed to register kprobe event: %s\n", call->name); |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1475 | unregister_ftrace_event(&tp->event); |
| 1476 | } |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1477 | return ret; |
| 1478 | } |
| 1479 | |
| 1480 | static void unregister_probe_event(struct trace_probe *tp) |
| 1481 | { |
Masami Hiramatsu | ff50d99 | 2009-08-13 16:35:34 -0400 | [diff] [blame] | 1482 | /* tp->event is unregistered in trace_remove_event_call() */ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1483 | trace_remove_event_call(&tp->call); |
| 1484 | } |
| 1485 | |
| 1486 | /* Make a debugfs interface for controling probe points */ |
| 1487 | static __init int init_kprobe_trace(void) |
| 1488 | { |
| 1489 | struct dentry *d_tracer; |
| 1490 | struct dentry *entry; |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1491 | |
| 1492 | d_tracer = tracing_init_dentry(); |
| 1493 | if (!d_tracer) |
| 1494 | return 0; |
| 1495 | |
| 1496 | entry = debugfs_create_file("kprobe_events", 0644, d_tracer, |
| 1497 | NULL, &kprobe_events_ops); |
| 1498 | |
Masami Hiramatsu | cd7e7bd | 2009-08-13 16:35:42 -0400 | [diff] [blame] | 1499 | /* Event list interface */ |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1500 | if (!entry) |
| 1501 | pr_warning("Could not create debugfs " |
| 1502 | "'kprobe_events' entry\n"); |
Masami Hiramatsu | cd7e7bd | 2009-08-13 16:35:42 -0400 | [diff] [blame] | 1503 | |
| 1504 | /* Profile interface */ |
| 1505 | entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, |
| 1506 | NULL, &kprobe_profile_ops); |
| 1507 | |
| 1508 | if (!entry) |
| 1509 | pr_warning("Could not create debugfs " |
| 1510 | "'kprobe_profile' entry\n"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1511 | return 0; |
| 1512 | } |
| 1513 | fs_initcall(init_kprobe_trace); |
| 1514 | |
| 1515 | |
| 1516 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
| 1517 | |
| 1518 | static int kprobe_trace_selftest_target(int a1, int a2, int a3, |
| 1519 | int a4, int a5, int a6) |
| 1520 | { |
| 1521 | return a1 + a2 + a3 + a4 + a5 + a6; |
| 1522 | } |
| 1523 | |
| 1524 | static __init int kprobe_trace_self_tests_init(void) |
| 1525 | { |
| 1526 | int ret; |
| 1527 | int (*target)(int, int, int, int, int, int); |
| 1528 | |
| 1529 | target = kprobe_trace_selftest_target; |
| 1530 | |
| 1531 | pr_info("Testing kprobe tracing: "); |
| 1532 | |
| 1533 | ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target " |
Masami Hiramatsu | f397af0 | 2009-10-16 20:07:20 -0400 | [diff] [blame] | 1534 | "$arg1 $arg2 $arg3 $arg4 $stack $stack0"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1535 | if (WARN_ON_ONCE(ret)) |
| 1536 | pr_warning("error enabling function entry\n"); |
| 1537 | |
| 1538 | ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target " |
Masami Hiramatsu | f397af0 | 2009-10-16 20:07:20 -0400 | [diff] [blame] | 1539 | "$retval"); |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 1540 | if (WARN_ON_ONCE(ret)) |
| 1541 | pr_warning("error enabling function return\n"); |
| 1542 | |
| 1543 | ret = target(1, 2, 3, 4, 5, 6); |
| 1544 | |
| 1545 | cleanup_all_probes(); |
| 1546 | |
| 1547 | pr_cont("OK\n"); |
| 1548 | return 0; |
| 1549 | } |
| 1550 | |
| 1551 | late_initcall(kprobe_trace_self_tests_init); |
| 1552 | |
| 1553 | #endif |