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

 /*
  * Performance event support for s390x
  *
  *  Copyright IBM Corp. 2012, 2013
  *  Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License (version 2 only)
  * as published by the Free Software Foundation.
  */
 #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/sysfs.h>
 #include <asm/irq.h>
 #include <asm/cpu_mf.h>
 #include <asm/lowcore.h>
 #include <asm/processor.h>
 #include <asm/sysinfo.h>

 const char *perf_pmu_name(void)
 {
 	if (cpum_cf_avail() || cpum_sf_avail())
 		return "CPU-Measurement Facilities (CPU-MF)";
 	return "pmu";
 }
 EXPORT_SYMBOL(perf_pmu_name);

 int perf_num_counters(void)
 {
 	int num = 0;

 	if (cpum_cf_avail())
 		num += PERF_CPUM_CF_MAX_CTR;
 	if (cpum_sf_avail())
 		num += PERF_CPUM_SF_MAX_CTR;

 	return num;
 }
 EXPORT_SYMBOL(perf_num_counters);

 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->empty1[0];
 }

 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);

 static int __perf_callchain_kernel(void *data, unsigned long address)
 {
 	struct perf_callchain_entry *entry = data;

 	perf_callchain_store(entry, address);
 	return 0;
 }

 void perf_callchain_kernel(struct perf_callchain_entry *entry,
 			   struct pt_regs *regs)
 {
 	if (user_mode(regs))
 		return;
 	dump_trace(__perf_callchain_kernel, entry, NULL, regs->gprs[15]);
 }

 /* 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,name=%s\n",
 		       pmu_attr->id, attr->attr.name);
 }

 /* Reserve/release functions for sharing perf hardware */
 static DEFINE_SPINLOCK(perf_hw_owner_lock);
 static void *perf_sampling_owner;

 int perf_reserve_sampling(void)
 {
 	int err;

 	err = 0;
 	spin_lock(&perf_hw_owner_lock);
 	if (perf_sampling_owner) {
 		pr_warn("The sampling facility is already reserved by %p\n",
 			perf_sampling_owner);
 		err = -EBUSY;
 	} else
 		perf_sampling_owner = __builtin_return_address(0);
 	spin_unlock(&perf_hw_owner_lock);
 	return err;
 }
 EXPORT_SYMBOL(perf_reserve_sampling);

 void perf_release_sampling(void)
 {
 	spin_lock(&perf_hw_owner_lock);
 	WARN_ON(!perf_sampling_owner);
 	perf_sampling_owner = NULL;
 	spin_unlock(&perf_hw_owner_lock);
 }
 EXPORT_SYMBOL(perf_release_sampling);
	/*
	* Performance event support for s390x
	*
	* Copyright IBM Corp. 2012, 2013
	* Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License (version 2 only)
	* as published by the Free Software Foundation.
	*/
	#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/sysfs.h>
	#include <asm/irq.h>
	#include <asm/cpu_mf.h>
	#include <asm/lowcore.h>
	#include <asm/processor.h>
	#include <asm/sysinfo.h>

	const char *perf_pmu_name(void)
	{
	if (cpum_cf_avail() \|\| cpum_sf_avail())
	return "CPU-Measurement Facilities (CPU-MF)";
	return "pmu";
	}
	EXPORT_SYMBOL(perf_pmu_name);

	int perf_num_counters(void)
	{
	int num = 0;

	if (cpum_cf_avail())
	num += PERF_CPUM_CF_MAX_CTR;
	if (cpum_sf_avail())
	num += PERF_CPUM_SF_MAX_CTR;

	return num;
	}
	EXPORT_SYMBOL(perf_num_counters);

	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->empty1[0];
	}

	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);

	static int __perf_callchain_kernel(void *data, unsigned long address)
	{
	struct perf_callchain_entry *entry = data;

	perf_callchain_store(entry, address);
	return 0;
	}

	void perf_callchain_kernel(struct perf_callchain_entry *entry,
	struct pt_regs *regs)
	{
	if (user_mode(regs))
	return;
	dump_trace(__perf_callchain_kernel, entry, NULL, regs->gprs[15]);
	}

	/* 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,name=%s\n",
	pmu_attr->id, attr->attr.name);
	}

	/* Reserve/release functions for sharing perf hardware */
	static DEFINE_SPINLOCK(perf_hw_owner_lock);
	static void *perf_sampling_owner;

	int perf_reserve_sampling(void)
	{
	int err;

	err = 0;
	spin_lock(&perf_hw_owner_lock);
	if (perf_sampling_owner) {
	pr_warn("The sampling facility is already reserved by %p\n",
	perf_sampling_owner);
	err = -EBUSY;
	} else
	perf_sampling_owner = __builtin_return_address(0);
	spin_unlock(&perf_hw_owner_lock);
	return err;
	}
	EXPORT_SYMBOL(perf_reserve_sampling);

	void perf_release_sampling(void)
	{
	spin_lock(&perf_hw_owner_lock);
	WARN_ON(!perf_sampling_owner);
	perf_sampling_owner = NULL;
	spin_unlock(&perf_hw_owner_lock);
	}
	EXPORT_SYMBOL(perf_release_sampling);