arch/s390/kernel/perf_event.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Performance event support for s390x
  *
  *  Copyright IBM Corp. 2012, 2013
  *  Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
  */
 #define KMSG_COMPONENT	"perf"
 #define pr_fmt(fmt)	KMSG_COMPONENT ": " fmt

 #include <linux/kernel.h>
 #include <linux/perf_event.h>
 #include <linux/kvm_host.h>
 #include <linux/percpu.h>
 #include <linux/export.h>
 #include <linux/seq_file.h>
 #include <linux/spinlock.h>
 #include <linux/uaccess.h>
 #include <linux/compat.h>
 #include <linux/sysfs.h>
 #include <asm/stacktrace.h>
 #include <asm/irq.h>
 #include <asm/cpu_mf.h>
 #include <asm/lowcore.h>
 #include <asm/processor.h>
 #include <asm/sysinfo.h>
 #include <asm/unwind.h>

 static struct kvm_s390_sie_block *sie_block(struct pt_regs *regs)
 {
 	struct stack_frame *stack = (struct stack_frame *) regs->gprs[15];

 	if (!stack)
 		return NULL;

 	return (struct kvm_s390_sie_block *)stack->sie_control_block;
 }

 static bool is_in_guest(struct pt_regs *regs)
 {
 	if (user_mode(regs))
 		return false;
 #if IS_ENABLED(CONFIG_KVM)
 	return instruction_pointer(regs) == (unsigned long) &sie_exit;
 #else
 	return false;
 #endif
 }

 static unsigned long guest_is_user_mode(struct pt_regs *regs)
 {
 	return sie_block(regs)->gpsw.mask & PSW_MASK_PSTATE;
 }

 static unsigned long instruction_pointer_guest(struct pt_regs *regs)
 {
 	return sie_block(regs)->gpsw.addr;
 }

 unsigned long perf_instruction_pointer(struct pt_regs *regs)
 {
 	return is_in_guest(regs) ? instruction_pointer_guest(regs)
 				 : instruction_pointer(regs);
 }

 static unsigned long perf_misc_guest_flags(struct pt_regs *regs)
 {
 	return guest_is_user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER
 					: PERF_RECORD_MISC_GUEST_KERNEL;
 }

 static unsigned long perf_misc_flags_sf(struct pt_regs *regs)
 {
 	struct perf_sf_sde_regs *sde_regs;
 	unsigned long flags;

 	sde_regs = (struct perf_sf_sde_regs *) &regs->int_parm_long;
 	if (sde_regs->in_guest)
 		flags = user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER
 					: PERF_RECORD_MISC_GUEST_KERNEL;
 	else
 		flags = user_mode(regs) ? PERF_RECORD_MISC_USER
 					: PERF_RECORD_MISC_KERNEL;
 	return flags;
 }

 unsigned long perf_misc_flags(struct pt_regs *regs)
 {
 	/* Check if the cpum_sf PMU has created the pt_regs structure.
 	 * In this case, perf misc flags can be easily extracted.  Otherwise,
 	 * do regular checks on the pt_regs content.
 	 */
 	if (regs->int_code == 0x1407 && regs->int_parm == CPU_MF_INT_SF_PRA)
 		if (!regs->gprs[15])
 			return perf_misc_flags_sf(regs);

 	if (is_in_guest(regs))
 		return perf_misc_guest_flags(regs);

 	return user_mode(regs) ? PERF_RECORD_MISC_USER
 			       : PERF_RECORD_MISC_KERNEL;
 }

 static void print_debug_cf(void)
 {
 	struct cpumf_ctr_info cf_info;
 	int cpu = smp_processor_id();

 	memset(&cf_info, 0, sizeof(cf_info));
 	if (!qctri(&cf_info))
 		pr_info("CPU[%i] CPUM_CF: ver=%u.%u A=%04x E=%04x C=%04x\n",
 			cpu, cf_info.cfvn, cf_info.csvn,
 			cf_info.auth_ctl, cf_info.enable_ctl, cf_info.act_ctl);
 }

 static void print_debug_sf(void)
 {
 	struct hws_qsi_info_block si;
 	int cpu = smp_processor_id();

 	memset(&si, 0, sizeof(si));
 	if (qsi(&si))
 		return;

 	pr_info("CPU[%i] CPUM_SF: basic=%i diag=%i min=%lu max=%lu cpu_speed=%u\n",
 		cpu, si.as, si.ad, si.min_sampl_rate, si.max_sampl_rate,
 		si.cpu_speed);

 	if (si.as)
 		pr_info("CPU[%i] CPUM_SF: Basic-sampling: a=%i e=%i c=%i"
 			" bsdes=%i tear=%016lx dear=%016lx\n", cpu,
 			si.as, si.es, si.cs, si.bsdes, si.tear, si.dear);
 	if (si.ad)
 		pr_info("CPU[%i] CPUM_SF: Diagnostic-sampling: a=%i e=%i c=%i"
 			" dsdes=%i tear=%016lx dear=%016lx\n", cpu,
 			si.ad, si.ed, si.cd, si.dsdes, si.tear, si.dear);
 }

 void perf_event_print_debug(void)
 {
 	unsigned long flags;

 	local_irq_save(flags);
 	if (cpum_cf_avail())
 		print_debug_cf();
 	if (cpum_sf_avail())
 		print_debug_sf();
 	local_irq_restore(flags);
 }

 /* Service level infrastructure */
 static void sl_print_counter(struct seq_file *m)
 {
 	struct cpumf_ctr_info ci;

 	memset(&ci, 0, sizeof(ci));
 	if (qctri(&ci))
 		return;

 	seq_printf(m, "CPU-MF: Counter facility: version=%u.%u "
 		   "authorization=%04x\n", ci.cfvn, ci.csvn, ci.auth_ctl);
 }

 static void sl_print_sampling(struct seq_file *m)
 {
 	struct hws_qsi_info_block si;

 	memset(&si, 0, sizeof(si));
 	if (qsi(&si))
 		return;

 	if (!si.as && !si.ad)
 		return;

 	seq_printf(m, "CPU-MF: Sampling facility: min_rate=%lu max_rate=%lu"
 		   " cpu_speed=%u\n", si.min_sampl_rate, si.max_sampl_rate,
 		   si.cpu_speed);
 	if (si.as)
 		seq_printf(m, "CPU-MF: Sampling facility: mode=basic"
 			   " sample_size=%u\n", si.bsdes);
 	if (si.ad)
 		seq_printf(m, "CPU-MF: Sampling facility: mode=diagnostic"
 			   " sample_size=%u\n", si.dsdes);
 }

 static void service_level_perf_print(struct seq_file *m,
 				     struct service_level *sl)
 {
 	if (cpum_cf_avail())
 		sl_print_counter(m);
 	if (cpum_sf_avail())
 		sl_print_sampling(m);
 }

 static struct service_level service_level_perf = {
 	.seq_print = service_level_perf_print,
 };

 static int __init service_level_perf_register(void)
 {
 	return register_service_level(&service_level_perf);
 }
 arch_initcall(service_level_perf_register);

 void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
 			   struct pt_regs *regs)
 {
 	struct unwind_state state;
 	unsigned long addr;

 	unwind_for_each_frame(&state, current, regs, 0) {
 		addr = unwind_get_return_address(&state);
 		if (!addr || perf_callchain_store(entry, addr))
 			return;
 	}
 }

 void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
 			 struct pt_regs *regs)
 {
 	struct stack_frame_user __user *sf;
 	unsigned long ip, sp;
 	bool first = true;

 	if (is_compat_task())
 		return;
 	perf_callchain_store(entry, instruction_pointer(regs));
 	sf = (void __user *)user_stack_pointer(regs);
 	pagefault_disable();
 	while (entry->nr < entry->max_stack) {
 		if (__get_user(sp, &sf->back_chain))
 			break;
 		if (__get_user(ip, &sf->gprs[8]))
 			break;
 		if (ip & 0x1) {
 			/*
 			 * If the instruction address is invalid, and this
 			 * is the first stack frame, assume r14 has not
 			 * been written to the stack yet. Otherwise exit.
 			 */
 			if (first && !(regs->gprs[14] & 0x1))
 				ip = regs->gprs[14];
 			else
 				break;
 		}
 		perf_callchain_store(entry, ip);
 		/* Sanity check: ABI requires SP to be aligned 8 bytes. */
 		if (!sp || sp & 0x7)
 			break;
 		sf = (void __user *)sp;
 		first = false;
 	}
 	pagefault_enable();
 }

 /* Perf definitions for PMU event attributes in sysfs */
 ssize_t cpumf_events_sysfs_show(struct device *dev,
 				struct device_attribute *attr, char *page)
 {
 	struct perf_pmu_events_attr *pmu_attr;

 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
 	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Performance event support for s390x
	*
	* Copyright IBM Corp. 2012, 2013
	* Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
	*/
	#define KMSG_COMPONENT "perf"
	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

	#include <linux/kernel.h>
	#include <linux/perf_event.h>
	#include <linux/kvm_host.h>
	#include <linux/percpu.h>
	#include <linux/export.h>
	#include <linux/seq_file.h>
	#include <linux/spinlock.h>
	#include <linux/uaccess.h>
	#include <linux/compat.h>
	#include <linux/sysfs.h>
	#include <asm/stacktrace.h>
	#include <asm/irq.h>
	#include <asm/cpu_mf.h>
	#include <asm/lowcore.h>
	#include <asm/processor.h>
	#include <asm/sysinfo.h>
	#include <asm/unwind.h>

	static struct kvm_s390_sie_block sie_block(struct pt_regs regs)
	{
	struct stack_frame stack = (struct stack_frame ) regs->gprs[15];

	if (!stack)
	return NULL;

	return (struct kvm_s390_sie_block *)stack->sie_control_block;
	}

	static bool is_in_guest(struct pt_regs *regs)
	{
	if (user_mode(regs))
	return false;
	#if IS_ENABLED(CONFIG_KVM)
	return instruction_pointer(regs) == (unsigned long) &sie_exit;
	#else
	return false;
	#endif
	}

	static unsigned long guest_is_user_mode(struct pt_regs *regs)
	{
	return sie_block(regs)->gpsw.mask & PSW_MASK_PSTATE;
	}

	static unsigned long instruction_pointer_guest(struct pt_regs *regs)
	{
	return sie_block(regs)->gpsw.addr;
	}

	unsigned long perf_instruction_pointer(struct pt_regs *regs)
	{
	return is_in_guest(regs) ? instruction_pointer_guest(regs)
	: instruction_pointer(regs);
	}

	static unsigned long perf_misc_guest_flags(struct pt_regs *regs)
	{
	return guest_is_user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER
	: PERF_RECORD_MISC_GUEST_KERNEL;
	}

	static unsigned long perf_misc_flags_sf(struct pt_regs *regs)
	{
	struct perf_sf_sde_regs *sde_regs;
	unsigned long flags;

	sde_regs = (struct perf_sf_sde_regs *) &regs->int_parm_long;
	if (sde_regs->in_guest)
	flags = user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER
	: PERF_RECORD_MISC_GUEST_KERNEL;
	else
	flags = user_mode(regs) ? PERF_RECORD_MISC_USER
	: PERF_RECORD_MISC_KERNEL;
	return flags;
	}

	unsigned long perf_misc_flags(struct pt_regs *regs)
	{
	/* Check if the cpum_sf PMU has created the pt_regs structure.
	* In this case, perf misc flags can be easily extracted. Otherwise,
	* do regular checks on the pt_regs content.
	*/
	if (regs->int_code == 0x1407 && regs->int_parm == CPU_MF_INT_SF_PRA)
	if (!regs->gprs[15])
	return perf_misc_flags_sf(regs);

	if (is_in_guest(regs))
	return perf_misc_guest_flags(regs);

	return user_mode(regs) ? PERF_RECORD_MISC_USER
	: PERF_RECORD_MISC_KERNEL;
	}

	static void print_debug_cf(void)
	{
	struct cpumf_ctr_info cf_info;
	int cpu = smp_processor_id();

	memset(&cf_info, 0, sizeof(cf_info));
	if (!qctri(&cf_info))
	pr_info("CPU[%i] CPUM_CF: ver=%u.%u A=%04x E=%04x C=%04x\n",
	cpu, cf_info.cfvn, cf_info.csvn,
	cf_info.auth_ctl, cf_info.enable_ctl, cf_info.act_ctl);
	}

	static void print_debug_sf(void)
	{
	struct hws_qsi_info_block si;
	int cpu = smp_processor_id();

	memset(&si, 0, sizeof(si));
	if (qsi(&si))
	return;

	pr_info("CPU[%i] CPUM_SF: basic=%i diag=%i min=%lu max=%lu cpu_speed=%u\n",
	cpu, si.as, si.ad, si.min_sampl_rate, si.max_sampl_rate,
	si.cpu_speed);

	if (si.as)
	pr_info("CPU[%i] CPUM_SF: Basic-sampling: a=%i e=%i c=%i"
	" bsdes=%i tear=%016lx dear=%016lx\n", cpu,
	si.as, si.es, si.cs, si.bsdes, si.tear, si.dear);
	if (si.ad)
	pr_info("CPU[%i] CPUM_SF: Diagnostic-sampling: a=%i e=%i c=%i"
	" dsdes=%i tear=%016lx dear=%016lx\n", cpu,
	si.ad, si.ed, si.cd, si.dsdes, si.tear, si.dear);
	}

	void perf_event_print_debug(void)
	{
	unsigned long flags;

	local_irq_save(flags);
	if (cpum_cf_avail())
	print_debug_cf();
	if (cpum_sf_avail())
	print_debug_sf();
	local_irq_restore(flags);
	}

	/* Service level infrastructure */
	static void sl_print_counter(struct seq_file *m)
	{
	struct cpumf_ctr_info ci;

	memset(&ci, 0, sizeof(ci));
	if (qctri(&ci))
	return;

	seq_printf(m, "CPU-MF: Counter facility: version=%u.%u "
	"authorization=%04x\n", ci.cfvn, ci.csvn, ci.auth_ctl);
	}

	static void sl_print_sampling(struct seq_file *m)
	{
	struct hws_qsi_info_block si;

	memset(&si, 0, sizeof(si));
	if (qsi(&si))
	return;

	if (!si.as && !si.ad)
	return;

	seq_printf(m, "CPU-MF: Sampling facility: min_rate=%lu max_rate=%lu"
	" cpu_speed=%u\n", si.min_sampl_rate, si.max_sampl_rate,
	si.cpu_speed);
	if (si.as)
	seq_printf(m, "CPU-MF: Sampling facility: mode=basic"
	" sample_size=%u\n", si.bsdes);
	if (si.ad)
	seq_printf(m, "CPU-MF: Sampling facility: mode=diagnostic"
	" sample_size=%u\n", si.dsdes);
	}

	static void service_level_perf_print(struct seq_file *m,
	struct service_level *sl)
	{
	if (cpum_cf_avail())
	sl_print_counter(m);
	if (cpum_sf_avail())
	sl_print_sampling(m);
	}

	static struct service_level service_level_perf = {
	.seq_print = service_level_perf_print,
	};

	static int __init service_level_perf_register(void)
	{
	return register_service_level(&service_level_perf);
	}
	arch_initcall(service_level_perf_register);

	void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
	struct pt_regs *regs)
	{
	struct unwind_state state;
	unsigned long addr;

	unwind_for_each_frame(&state, current, regs, 0) {
	addr = unwind_get_return_address(&state);
	if (!addr \|\| perf_callchain_store(entry, addr))
	return;
	}
	}

	void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
	struct pt_regs *regs)
	{
	struct stack_frame_user __user *sf;
	unsigned long ip, sp;
	bool first = true;

	if (is_compat_task())
	return;
	perf_callchain_store(entry, instruction_pointer(regs));
	sf = (void __user *)user_stack_pointer(regs);
	pagefault_disable();
	while (entry->nr < entry->max_stack) {
	if (__get_user(sp, &sf->back_chain))
	break;
	if (__get_user(ip, &sf->gprs[8]))
	break;
	if (ip & 0x1) {
	/*
	* If the instruction address is invalid, and this
	* is the first stack frame, assume r14 has not
	* been written to the stack yet. Otherwise exit.
	*/
	if (first && !(regs->gprs[14] & 0x1))
	ip = regs->gprs[14];
	else
	break;
	}
	perf_callchain_store(entry, ip);
	/* Sanity check: ABI requires SP to be aligned 8 bytes. */
	if (!sp \|\| sp & 0x7)
	break;
	sf = (void __user *)sp;
	first = false;
	}
	pagefault_enable();
	}

	/* Perf definitions for PMU event attributes in sysfs */
	ssize_t cpumf_events_sysfs_show(struct device *dev,
	struct device_attribute attr, char page)
	{
	struct perf_pmu_events_attr *pmu_attr;

	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
	}