perf/x86: Add a microcode revision check for SNB-PEBS (c93dc84c) · Commits · EulixOS / Software / Kernel

arch/x86/include/asm/perf_event.h

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -232,6 +232,7 @@ struct perf_guest_switch_msr {

	extern struct perf_guest_switch_msr perf_guest_get_msrs(int nr);		extern struct perf_guest_switch_msr perf_guest_get_msrs(int nr);
	extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);		extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
			extern void perf_check_microcode(void);
	#else		#else
	static inline perf_guest_switch_msr perf_guest_get_msrs(int nr)		static inline perf_guest_switch_msr perf_guest_get_msrs(int nr)
	{		{
	@@ -245,6 +246,7 @@ static inline void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
	}		}

	static inline void perf_events_lapic_init(void) { }		static inline void perf_events_lapic_init(void) { }
			static inline void perf_check_microcode(void) { }
	#endif		#endif

	#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD)		#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD)

arch/x86/kernel/cpu/perf_event.c

+14 −7

Original line number	Original line	Diff line number	Diff line
	@@ -379,7 +379,7 @@ int x86_pmu_hw_config(struct perf_event *event)
	int precise = 0;		int precise = 0;

	/* Support for constant skid */		/* Support for constant skid */
	if (x86_pmu.pebs_active) {		if (x86_pmu.pebs_active && !x86_pmu.pebs_broken) {
	precise++;		precise++;

	/* Support for IP fixup */		/* Support for IP fixup */
	@@ -1650,6 +1650,13 @@ static void x86_pmu_flush_branch_stack(void)
	x86_pmu.flush_branch_stack();		x86_pmu.flush_branch_stack();
	}		}

			void perf_check_microcode(void)
			{
			if (x86_pmu.check_microcode)
			x86_pmu.check_microcode();
			}
			EXPORT_SYMBOL_GPL(perf_check_microcode);

	static struct pmu pmu = {		static struct pmu pmu = {
	.pmu_enable = x86_pmu_enable,		.pmu_enable = x86_pmu_enable,
	.pmu_disable = x86_pmu_disable,		.pmu_disable = x86_pmu_disable,

arch/x86/kernel/cpu/perf_event.h

+3 −1

Original line number	Original line	Diff line number	Diff line
	@@ -361,6 +361,8 @@ struct x86_pmu {
	void (*cpu_starting)(int cpu);		void (*cpu_starting)(int cpu);
	void (*cpu_dying)(int cpu);		void (*cpu_dying)(int cpu);
	void (*cpu_dead)(int cpu);		void (*cpu_dead)(int cpu);

			void (*check_microcode)(void);
	void (*flush_branch_stack)(void);		void (*flush_branch_stack)(void);

	/*		/*
	@@ -373,7 +375,7 @@ struct x86_pmu {
	* Intel DebugStore bits		* Intel DebugStore bits
	*/		*/
	int bts, pebs;		int bts, pebs;
	int bts_active, pebs_active;		int bts_active, pebs_active, pebs_broken;
	int pebs_record_size;		int pebs_record_size;
	void (drain_pebs)(struct pt_regs regs);		void (drain_pebs)(struct pt_regs regs);
	struct event_constraint *pebs_constraints;		struct event_constraint *pebs_constraints;

arch/x86/kernel/cpu/perf_event_intel.c

+48 −3

Original line number	Original line	Diff line number	Diff line
	@@ -1712,11 +1712,56 @@ static __init void intel_clovertown_quirk(void)
	x86_pmu.pebs_constraints = NULL;		x86_pmu.pebs_constraints = NULL;
	}		}

			static int intel_snb_pebs_broken(int cpu)
			{
			u32 rev = UINT_MAX; /* default to broken for unknown models */

			switch (cpu_data(cpu).x86_model) {
			case 42: /* SNB */
			rev = 0x28;
			break;

			case 45: /* SNB-EP */
			switch (cpu_data(cpu).x86_mask) {
			case 6: rev = 0x618; break;
			case 7: rev = 0x70c; break;
			}
			}

			return (cpu_data(cpu).microcode < rev);
			}

			static void intel_snb_check_microcode(void)
			{
			int pebs_broken = 0;
			int cpu;

			get_online_cpus();
			for_each_online_cpu(cpu) {
			if ((pebs_broken = intel_snb_pebs_broken(cpu)))
			break;
			}
			put_online_cpus();

			if (pebs_broken == x86_pmu.pebs_broken)
			return;

			/*
			* Serialized by the microcode lock..
			*/
			if (x86_pmu.pebs_broken) {
			pr_info("PEBS enabled due to microcode update\n");
			x86_pmu.pebs_broken = 0;
			} else {
			pr_info("PEBS disabled due to CPU errata, please upgrade microcode\n");
			x86_pmu.pebs_broken = 1;
			}
			}

	static __init void intel_sandybridge_quirk(void)		static __init void intel_sandybridge_quirk(void)
	{		{
	printk(KERN_WARNING "PEBS disabled due to CPU errata.\n");		x86_pmu.check_microcode = intel_snb_check_microcode;
	x86_pmu.pebs = 0;		intel_snb_check_microcode();
	x86_pmu.pebs_constraints = NULL;
	}		}

	static const struct { int id; char *name; } intel_arch_events_map[] __initconst = {		static const struct { int id; char *name; } intel_arch_events_map[] __initconst = {

arch/x86/kernel/microcode_core.c

+7 −3

Original line number	Original line	Diff line number	Diff line
	@@ -87,6 +87,7 @@
	#include <asm/microcode.h>		#include <asm/microcode.h>
	#include <asm/processor.h>		#include <asm/processor.h>
	#include <asm/cpu_device_id.h>		#include <asm/cpu_device_id.h>
			#include <asm/perf_event.h>

	MODULE_DESCRIPTION("Microcode Update Driver");		MODULE_DESCRIPTION("Microcode Update Driver");
	MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");		MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
	@@ -277,7 +278,6 @@ static int reload_for_cpu(int cpu)
	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;		struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
	int err = 0;		int err = 0;

	mutex_lock(&microcode_mutex);
	if (uci->valid) {		if (uci->valid) {
	enum ucode_state ustate;		enum ucode_state ustate;

	@@ -288,7 +288,6 @@ static int reload_for_cpu(int cpu)
	if (ustate == UCODE_ERROR)		if (ustate == UCODE_ERROR)
	err = -EINVAL;		err = -EINVAL;
	}		}
	mutex_unlock(&microcode_mutex);

	return err;		return err;
	}		}
	@@ -309,6 +308,7 @@ static ssize_t reload_store(struct device *dev,
	return size;		return size;

	get_online_cpus();		get_online_cpus();
			mutex_lock(&microcode_mutex);
	for_each_online_cpu(cpu) {		for_each_online_cpu(cpu) {
	tmp_ret = reload_for_cpu(cpu);		tmp_ret = reload_for_cpu(cpu);
	if (tmp_ret != 0)		if (tmp_ret != 0)
	@@ -318,6 +318,9 @@ static ssize_t reload_store(struct device *dev,
	if (!ret)		if (!ret)
	ret = tmp_ret;		ret = tmp_ret;
	}		}
			if (!ret)
			perf_check_microcode();
			mutex_unlock(&microcode_mutex);
	put_online_cpus();		put_online_cpus();

	if (!ret)		if (!ret)
	@@ -557,7 +560,8 @@ static int __init microcode_init(void)
	mutex_lock(&microcode_mutex);		mutex_lock(&microcode_mutex);

	error = subsys_interface_register(&mc_cpu_interface);		error = subsys_interface_register(&mc_cpu_interface);
			if (!error)
			perf_check_microcode();
	mutex_unlock(&microcode_mutex);		mutex_unlock(&microcode_mutex);
	put_online_cpus();		put_online_cpus();