6.10-stable review patch. If anyone has any objections, please let me know.
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From: Kan Liang kan.liang@linux.intel.com
[ Upstream commit a23eb2fc1d818cdac9b31f032842d55483a6a040 ]
The current perf assumes that the counters that support PEBS are contiguous. But it's not guaranteed with the new leaf 0x23 introduced. The counters are enumerated with a counter mask. There may be holes in the counter mask for future platforms or in a virtualization environment.
Store the PEBS event mask rather than the maximum number of PEBS counters in the x86 PMU structures.
Signed-off-by: Kan Liang kan.liang@linux.intel.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Reviewed-by: Andi Kleen ak@linux.intel.com Reviewed-by: Ian Rogers irogers@google.com Link: https://lkml.kernel.org/r/20240626143545.480761-2-kan.liang@linux.intel.com Stable-dep-of: f73cefa3b72e ("perf/x86: Fix smp_processor_id()-in-preemptible warnings") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/events/intel/core.c | 8 ++++---- arch/x86/events/intel/ds.c | 15 ++++++++------- arch/x86/events/perf_event.h | 15 +++++++++++++-- arch/x86/include/asm/intel_ds.h | 1 + 4 files changed, 26 insertions(+), 13 deletions(-)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 101a21fe9c213..2175ca2fdba47 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -4728,7 +4728,7 @@ static void intel_pmu_check_hybrid_pmus(struct x86_hybrid_pmu *pmu) { intel_pmu_check_num_counters(&pmu->num_counters, &pmu->num_counters_fixed, &pmu->intel_ctrl, (1ULL << pmu->num_counters_fixed) - 1); - pmu->max_pebs_events = min_t(unsigned, MAX_PEBS_EVENTS, pmu->num_counters); + pmu->pebs_events_mask = intel_pmu_pebs_mask(GENMASK_ULL(pmu->num_counters - 1, 0)); pmu->unconstrained = (struct event_constraint) __EVENT_CONSTRAINT(0, (1ULL << pmu->num_counters) - 1, 0, pmu->num_counters, 0, 0); @@ -6070,7 +6070,7 @@ static __always_inline int intel_pmu_init_hybrid(enum hybrid_pmu_type pmus)
pmu->num_counters = x86_pmu.num_counters; pmu->num_counters_fixed = x86_pmu.num_counters_fixed; - pmu->max_pebs_events = min_t(unsigned, MAX_PEBS_EVENTS, pmu->num_counters); + pmu->pebs_events_mask = intel_pmu_pebs_mask(GENMASK_ULL(pmu->num_counters - 1, 0)); pmu->unconstrained = (struct event_constraint) __EVENT_CONSTRAINT(0, (1ULL << pmu->num_counters) - 1, 0, pmu->num_counters, 0, 0); @@ -6193,7 +6193,7 @@ __init int intel_pmu_init(void) x86_pmu.events_maskl = ebx.full; x86_pmu.events_mask_len = eax.split.mask_length;
- x86_pmu.max_pebs_events = min_t(unsigned, MAX_PEBS_EVENTS, x86_pmu.num_counters); + x86_pmu.pebs_events_mask = intel_pmu_pebs_mask(GENMASK_ULL(x86_pmu.num_counters - 1, 0)); x86_pmu.pebs_capable = PEBS_COUNTER_MASK;
/* @@ -6826,7 +6826,7 @@ __init int intel_pmu_init(void) pmu->num_counters_fixed = x86_pmu.num_counters_fixed; }
- pmu->max_pebs_events = min_t(unsigned, MAX_PEBS_EVENTS, pmu->num_counters); + pmu->pebs_events_mask = intel_pmu_pebs_mask(GENMASK_ULL(pmu->num_counters - 1, 0)); pmu->unconstrained = (struct event_constraint) __EVENT_CONSTRAINT(0, (1ULL << pmu->num_counters) - 1, 0, pmu->num_counters, 0, 0); diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index 80a4f712217b7..87d3feb9f8fe8 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -1137,7 +1137,7 @@ void intel_pmu_pebs_sched_task(struct perf_event_pmu_context *pmu_ctx, bool sche static inline void pebs_update_threshold(struct cpu_hw_events *cpuc) { struct debug_store *ds = cpuc->ds; - int max_pebs_events = hybrid(cpuc->pmu, max_pebs_events); + int max_pebs_events = intel_pmu_max_num_pebs(cpuc->pmu); int num_counters_fixed = hybrid(cpuc->pmu, num_counters_fixed); u64 threshold; int reserved; @@ -2161,6 +2161,7 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs, struct perf_sample_d void *base, *at, *top; short counts[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS] = {}; short error[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS] = {}; + int max_pebs_events = intel_pmu_max_num_pebs(NULL); int bit, i, size; u64 mask;
@@ -2172,8 +2173,8 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs, struct perf_sample_d
ds->pebs_index = ds->pebs_buffer_base;
- mask = (1ULL << x86_pmu.max_pebs_events) - 1; - size = x86_pmu.max_pebs_events; + mask = x86_pmu.pebs_events_mask; + size = max_pebs_events; if (x86_pmu.flags & PMU_FL_PEBS_ALL) { mask |= ((1ULL << x86_pmu.num_counters_fixed) - 1) << INTEL_PMC_IDX_FIXED; size = INTEL_PMC_IDX_FIXED + x86_pmu.num_counters_fixed; @@ -2212,8 +2213,9 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs, struct perf_sample_d pebs_status = p->status = cpuc->pebs_enabled;
bit = find_first_bit((unsigned long *)&pebs_status, - x86_pmu.max_pebs_events); - if (bit >= x86_pmu.max_pebs_events) + max_pebs_events); + + if (!(x86_pmu.pebs_events_mask & (1 << bit))) continue;
/* @@ -2271,7 +2273,6 @@ static void intel_pmu_drain_pebs_icl(struct pt_regs *iregs, struct perf_sample_d { short counts[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS] = {}; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - int max_pebs_events = hybrid(cpuc->pmu, max_pebs_events); int num_counters_fixed = hybrid(cpuc->pmu, num_counters_fixed); struct debug_store *ds = cpuc->ds; struct perf_event *event; @@ -2287,7 +2288,7 @@ static void intel_pmu_drain_pebs_icl(struct pt_regs *iregs, struct perf_sample_d
ds->pebs_index = ds->pebs_buffer_base;
- mask = ((1ULL << max_pebs_events) - 1) | + mask = hybrid(cpuc->pmu, pebs_events_mask) | (((1ULL << num_counters_fixed) - 1) << INTEL_PMC_IDX_FIXED); size = INTEL_PMC_IDX_FIXED + num_counters_fixed;
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 72b022a1e16c5..a7ba2868018ca 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -684,7 +684,7 @@ struct x86_hybrid_pmu { cpumask_t supported_cpus; union perf_capabilities intel_cap; u64 intel_ctrl; - int max_pebs_events; + u64 pebs_events_mask; int num_counters; int num_counters_fixed; struct event_constraint unconstrained; @@ -852,7 +852,7 @@ struct x86_pmu { pebs_ept :1; int pebs_record_size; int pebs_buffer_size; - int max_pebs_events; + u64 pebs_events_mask; void (*drain_pebs)(struct pt_regs *regs, struct perf_sample_data *data); struct event_constraint *pebs_constraints; void (*pebs_aliases)(struct perf_event *event); @@ -1661,6 +1661,17 @@ static inline int is_ht_workaround_enabled(void) return !!(x86_pmu.flags & PMU_FL_EXCL_ENABLED); }
+static inline u64 intel_pmu_pebs_mask(u64 cntr_mask) +{ + return MAX_PEBS_EVENTS_MASK & cntr_mask; +} + +static inline int intel_pmu_max_num_pebs(struct pmu *pmu) +{ + static_assert(MAX_PEBS_EVENTS == 32); + return fls((u32)hybrid(pmu, pebs_events_mask)); +} + #else /* CONFIG_CPU_SUP_INTEL */
static inline void reserve_ds_buffers(void) diff --git a/arch/x86/include/asm/intel_ds.h b/arch/x86/include/asm/intel_ds.h index 2f9eeb5c3069a..5dbeac48a5b93 100644 --- a/arch/x86/include/asm/intel_ds.h +++ b/arch/x86/include/asm/intel_ds.h @@ -9,6 +9,7 @@ /* The maximal number of PEBS events: */ #define MAX_PEBS_EVENTS_FMT4 8 #define MAX_PEBS_EVENTS 32 +#define MAX_PEBS_EVENTS_MASK GENMASK_ULL(MAX_PEBS_EVENTS - 1, 0) #define MAX_FIXED_PEBS_EVENTS 16
/*