diff options
| author | Stephane Eranian <eranian@google.com> | 2022-03-22 15:15:11 -0700 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-04-05 10:24:38 +0200 |
| commit | cc37e520a236069c0de0e7ea455082fa11c73b12 (patch) | |
| tree | 12c7c8e3d54956226acad111dbe0b5fa871f8816 | |
| parent | ba2fe7500845a30fc845a72081999cf632051862 (diff) | |
perf/x86/amd: Make Zen3 branch sampling opt-in
Add a kernel config option CONFIG_PERF_EVENTS_AMD_BRS
to make the support for AMD Zen3 Branch Sampling (BRS) an opt-in
compile time option.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220322221517.2510440-8-eranian@google.com
| -rw-r--r-- | arch/x86/events/Kconfig | 8 | ||||
| -rw-r--r-- | arch/x86/events/amd/Makefile | 3 | ||||
| -rw-r--r-- | arch/x86/events/perf_event.h | 49 |
3 files changed, 49 insertions, 11 deletions
diff --git a/arch/x86/events/Kconfig b/arch/x86/events/Kconfig index d6cdfe631674..09c56965750a 100644 --- a/arch/x86/events/Kconfig +++ b/arch/x86/events/Kconfig @@ -44,4 +44,12 @@ config PERF_EVENTS_AMD_UNCORE To compile this driver as a module, choose M here: the module will be called 'amd-uncore'. + +config PERF_EVENTS_AMD_BRS + depends on PERF_EVENTS && CPU_SUP_AMD + bool "AMD Zen3 Branch Sampling support" + help + Enable AMD Zen3 branch sampling support (BRS) which samples up to + 16 consecutive taken branches in registers. + endmenu diff --git a/arch/x86/events/amd/Makefile b/arch/x86/events/amd/Makefile index cf323ffab5cd..b9f5d4610256 100644 --- a/arch/x86/events/amd/Makefile +++ b/arch/x86/events/amd/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_CPU_SUP_AMD) += core.o brs.o +obj-$(CONFIG_CPU_SUP_AMD) += core.o +obj-$(CONFIG_PERF_EVENTS_AMD_BRS) += brs.o obj-$(CONFIG_PERF_EVENTS_AMD_POWER) += power.o obj-$(CONFIG_X86_LOCAL_APIC) += ibs.o obj-$(CONFIG_PERF_EVENTS_AMD_UNCORE) += amd-uncore.o diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index d91ff2c6cefe..ef27aee04b13 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -1218,6 +1218,8 @@ static inline bool fixed_counter_disabled(int i, struct pmu *pmu) #ifdef CONFIG_CPU_SUP_AMD int amd_pmu_init(void); + +#ifdef CONFIG_PERF_EVENTS_AMD_BRS int amd_brs_init(void); void amd_brs_disable(void); void amd_brs_enable(void); @@ -1252,25 +1254,52 @@ static inline void amd_pmu_brs_del(struct perf_event *event) void amd_pmu_brs_sched_task(struct perf_event_context *ctx, bool sched_in); -/* - * check if BRS is activated on the CPU - * active defined as it has non-zero users and DBG_EXT_CFG.BRSEN=1 - */ -static inline bool amd_brs_active(void) +static inline s64 amd_brs_adjust_period(s64 period) { - struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + if (period > x86_pmu.lbr_nr) + return period - x86_pmu.lbr_nr; - return cpuc->brs_active; + return period; +} +#else +static inline int amd_brs_init(void) +{ + return 0; } +static inline void amd_brs_disable(void) {} +static inline void amd_brs_enable(void) {} +static inline void amd_brs_drain(void) {} +static inline void amd_brs_lopwr_init(void) {} +static inline void amd_brs_disable_all(void) {} +static inline int amd_brs_setup_filter(struct perf_event *event) +{ + return 0; +} +static inline void amd_brs_reset(void) {} -static inline s64 amd_brs_adjust_period(s64 period) +static inline void amd_pmu_brs_add(struct perf_event *event) { - if (period > x86_pmu.lbr_nr) - return period - x86_pmu.lbr_nr; +} + +static inline void amd_pmu_brs_del(struct perf_event *event) +{ +} + +static inline void amd_pmu_brs_sched_task(struct perf_event_context *ctx, bool sched_in) +{ +} +static inline s64 amd_brs_adjust_period(s64 period) +{ return period; } +static inline void amd_brs_enable_all(void) +{ +} + +#endif + #else /* CONFIG_CPU_SUP_AMD */ static inline int amd_pmu_init(void) |