From: Dapeng Mi Date: Wed, 29 Oct 2025 10:21:29 +0000 (+0800) Subject: perf/x86/intel: Initialize architectural PEBS X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d243d0bb64af1e90ec18ac2fa6e7cadfe8895913;p=thirdparty%2Fkernel%2Flinux.git perf/x86/intel: Initialize architectural PEBS arch-PEBS leverages CPUID.23H.4/5 sub-leaves enumerate arch-PEBS supported capabilities and counters bitmap. This patch parses these 2 sub-leaves and initializes arch-PEBS capabilities and corresponding structures. Since IA32_PEBS_ENABLE and MSR_PEBS_DATA_CFG MSRs are no longer existed for arch-PEBS, arch-PEBS doesn't need to manipulate these MSRs. Thus add a simple pair of __intel_pmu_pebs_enable/disable() callbacks for arch-PEBS. Signed-off-by: Dapeng Mi Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251029102136.61364-6-dapeng1.mi@linux.intel.com --- diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index b2868fee765b3..5d0d5e466c623 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -554,14 +554,22 @@ static inline int precise_br_compat(struct perf_event *event) return m == b; } -int x86_pmu_max_precise(void) +int x86_pmu_max_precise(struct pmu *pmu) { int precise = 0; - /* Support for constant skid */ if (x86_pmu.pebs_active && !x86_pmu.pebs_broken) { - precise++; + /* arch PEBS */ + if (x86_pmu.arch_pebs) { + precise = 2; + if (hybrid(pmu, arch_pebs_cap).pdists) + precise++; + + return precise; + } + /* legacy PEBS - support for constant skid */ + precise++; /* Support for IP fixup */ if (x86_pmu.lbr_nr || x86_pmu.intel_cap.pebs_format >= 2) precise++; @@ -569,13 +577,14 @@ int x86_pmu_max_precise(void) if (x86_pmu.pebs_prec_dist) precise++; } + return precise; } int x86_pmu_hw_config(struct perf_event *event) { if (event->attr.precise_ip) { - int precise = x86_pmu_max_precise(); + int precise = x86_pmu_max_precise(event->pmu); if (event->attr.precise_ip > precise) return -EOPNOTSUPP; @@ -2630,7 +2639,9 @@ static ssize_t max_precise_show(struct device *cdev, struct device_attribute *attr, char *buf) { - return snprintf(buf, PAGE_SIZE, "%d\n", x86_pmu_max_precise()); + struct pmu *pmu = dev_get_drvdata(cdev); + + return snprintf(buf, PAGE_SIZE, "%d\n", x86_pmu_max_precise(pmu)); } static DEVICE_ATTR_RO(max_precise); diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index c88bcd5d2bc44..9ce27b3269239 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -5271,34 +5271,59 @@ static inline bool intel_pmu_broken_perf_cap(void) return false; } +#define counter_mask(_gp, _fixed) ((_gp) | ((u64)(_fixed) << INTEL_PMC_IDX_FIXED)) + static void update_pmu_cap(struct pmu *pmu) { - unsigned int cntr, fixed_cntr, ecx, edx; - union cpuid35_eax eax; - union cpuid35_ebx ebx; + unsigned int eax, ebx, ecx, edx; + union cpuid35_eax eax_0; + union cpuid35_ebx ebx_0; + u64 cntrs_mask = 0; + u64 pebs_mask = 0; + u64 pdists_mask = 0; - cpuid(ARCH_PERFMON_EXT_LEAF, &eax.full, &ebx.full, &ecx, &edx); + cpuid(ARCH_PERFMON_EXT_LEAF, &eax_0.full, &ebx_0.full, &ecx, &edx); - if (ebx.split.umask2) + if (ebx_0.split.umask2) hybrid(pmu, config_mask) |= ARCH_PERFMON_EVENTSEL_UMASK2; - if (ebx.split.eq) + if (ebx_0.split.eq) hybrid(pmu, config_mask) |= ARCH_PERFMON_EVENTSEL_EQ; - if (eax.split.cntr_subleaf) { + if (eax_0.split.cntr_subleaf) { cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_NUM_COUNTER_LEAF, - &cntr, &fixed_cntr, &ecx, &edx); - hybrid(pmu, cntr_mask64) = cntr; - hybrid(pmu, fixed_cntr_mask64) = fixed_cntr; + &eax, &ebx, &ecx, &edx); + hybrid(pmu, cntr_mask64) = eax; + hybrid(pmu, fixed_cntr_mask64) = ebx; + cntrs_mask = counter_mask(eax, ebx); } - if (eax.split.acr_subleaf) { + if (eax_0.split.acr_subleaf) { cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_ACR_LEAF, - &cntr, &fixed_cntr, &ecx, &edx); + &eax, &ebx, &ecx, &edx); /* The mask of the counters which can be reloaded */ - hybrid(pmu, acr_cntr_mask64) = cntr | ((u64)fixed_cntr << INTEL_PMC_IDX_FIXED); - + hybrid(pmu, acr_cntr_mask64) = counter_mask(eax, ebx); /* The mask of the counters which can cause a reload of reloadable counters */ - hybrid(pmu, acr_cause_mask64) = ecx | ((u64)edx << INTEL_PMC_IDX_FIXED); + hybrid(pmu, acr_cause_mask64) = counter_mask(ecx, edx); + } + + /* Bits[5:4] should be set simultaneously if arch-PEBS is supported */ + if (eax_0.split.pebs_caps_subleaf && eax_0.split.pebs_cnts_subleaf) { + cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_PEBS_CAP_LEAF, + &eax, &ebx, &ecx, &edx); + hybrid(pmu, arch_pebs_cap).caps = (u64)ebx << 32; + + cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_PEBS_COUNTER_LEAF, + &eax, &ebx, &ecx, &edx); + pebs_mask = counter_mask(eax, ecx); + pdists_mask = counter_mask(ebx, edx); + hybrid(pmu, arch_pebs_cap).counters = pebs_mask; + hybrid(pmu, arch_pebs_cap).pdists = pdists_mask; + + if (WARN_ON((pebs_mask | pdists_mask) & ~cntrs_mask)) + x86_pmu.arch_pebs = 0; + } else { + WARN_ON(x86_pmu.arch_pebs == 1); + x86_pmu.arch_pebs = 0; } if (!intel_pmu_broken_perf_cap()) { @@ -6252,7 +6277,7 @@ tsx_is_visible(struct kobject *kobj, struct attribute *attr, int i) static umode_t pebs_is_visible(struct kobject *kobj, struct attribute *attr, int i) { - return x86_pmu.ds_pebs ? attr->mode : 0; + return intel_pmu_has_pebs() ? attr->mode : 0; } static umode_t @@ -7728,6 +7753,9 @@ __init int intel_pmu_init(void) if (!is_hybrid() && boot_cpu_has(X86_FEATURE_ARCH_PERFMON_EXT)) update_pmu_cap(NULL); + if (x86_pmu.arch_pebs) + pr_cont("Architectural PEBS, "); + intel_pmu_check_counters_mask(&x86_pmu.cntr_mask64, &x86_pmu.fixed_cntr_mask64, &x86_pmu.intel_ctrl); diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index c0b7ac1c7594e..26e485eca0a05 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -1531,6 +1531,15 @@ static inline void intel_pmu_drain_large_pebs(struct cpu_hw_events *cpuc) intel_pmu_drain_pebs_buffer(); } +static void __intel_pmu_pebs_enable(struct perf_event *event) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + struct hw_perf_event *hwc = &event->hw; + + hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT; + cpuc->pebs_enabled |= 1ULL << hwc->idx; +} + void intel_pmu_pebs_enable(struct perf_event *event) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); @@ -1539,9 +1548,7 @@ void intel_pmu_pebs_enable(struct perf_event *event) struct debug_store *ds = cpuc->ds; unsigned int idx = hwc->idx; - hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT; - - cpuc->pebs_enabled |= 1ULL << hwc->idx; + __intel_pmu_pebs_enable(event); if ((event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT) && (x86_pmu.version < 5)) cpuc->pebs_enabled |= 1ULL << (hwc->idx + 32); @@ -1603,14 +1610,22 @@ void intel_pmu_pebs_del(struct perf_event *event) pebs_update_state(needed_cb, cpuc, event, false); } -void intel_pmu_pebs_disable(struct perf_event *event) +static void __intel_pmu_pebs_disable(struct perf_event *event) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct hw_perf_event *hwc = &event->hw; intel_pmu_drain_large_pebs(cpuc); - cpuc->pebs_enabled &= ~(1ULL << hwc->idx); + hwc->config |= ARCH_PERFMON_EVENTSEL_INT; +} + +void intel_pmu_pebs_disable(struct perf_event *event) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + struct hw_perf_event *hwc = &event->hw; + + __intel_pmu_pebs_disable(event); if ((event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT) && (x86_pmu.version < 5)) @@ -1622,8 +1637,6 @@ void intel_pmu_pebs_disable(struct perf_event *event) if (cpuc->enabled) wrmsrq(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled); - - hwc->config |= ARCH_PERFMON_EVENTSEL_INT; } void intel_pmu_pebs_enable_all(void) @@ -2669,11 +2682,26 @@ static void intel_pmu_drain_pebs_icl(struct pt_regs *iregs, struct perf_sample_d } } +static void __init intel_arch_pebs_init(void) +{ + /* + * Current hybrid platforms always both support arch-PEBS or not + * on all kinds of cores. So directly set x86_pmu.arch_pebs flag + * if boot cpu supports arch-PEBS. + */ + x86_pmu.arch_pebs = 1; + x86_pmu.pebs_buffer_size = PEBS_BUFFER_SIZE; + x86_pmu.pebs_capable = ~0ULL; + + x86_pmu.pebs_enable = __intel_pmu_pebs_enable; + x86_pmu.pebs_disable = __intel_pmu_pebs_disable; +} + /* * PEBS probe and setup */ -void __init intel_pebs_init(void) +static void __init intel_ds_pebs_init(void) { /* * No support for 32bit formats @@ -2788,6 +2816,14 @@ void __init intel_pebs_init(void) } } +void __init intel_pebs_init(void) +{ + if (x86_pmu.intel_cap.pebs_format == 0xf) + intel_arch_pebs_init(); + else + intel_ds_pebs_init(); +} + void perf_restore_debug_store(void) { struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds); diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 285779c734796..ca5289980b527 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -708,6 +708,12 @@ enum hybrid_pmu_type { hybrid_big_small_tiny = hybrid_big | hybrid_small_tiny, }; +struct arch_pebs_cap { + u64 caps; + u64 counters; + u64 pdists; +}; + struct x86_hybrid_pmu { struct pmu pmu; const char *name; @@ -752,6 +758,8 @@ struct x86_hybrid_pmu { mid_ack :1, enabled_ack :1; + struct arch_pebs_cap arch_pebs_cap; + u64 pebs_data_source[PERF_PEBS_DATA_SOURCE_MAX]; }; @@ -906,7 +914,7 @@ struct x86_pmu { union perf_capabilities intel_cap; /* - * Intel DebugStore bits + * Intel DebugStore and PEBS bits */ unsigned int bts :1, bts_active :1, @@ -917,7 +925,8 @@ struct x86_pmu { pebs_no_tlb :1, pebs_no_isolation :1, pebs_block :1, - pebs_ept :1; + pebs_ept :1, + arch_pebs :1; int pebs_record_size; int pebs_buffer_size; u64 pebs_events_mask; @@ -929,6 +938,11 @@ struct x86_pmu { u64 rtm_abort_event; u64 pebs_capable; + /* + * Intel Architectural PEBS + */ + struct arch_pebs_cap arch_pebs_cap; + /* * Intel LBR */ @@ -1216,7 +1230,7 @@ int x86_reserve_hardware(void); void x86_release_hardware(void); -int x86_pmu_max_precise(void); +int x86_pmu_max_precise(struct pmu *pmu); void hw_perf_lbr_event_destroy(struct perf_event *event); @@ -1791,6 +1805,11 @@ static inline int intel_pmu_max_num_pebs(struct pmu *pmu) return fls((u32)hybrid(pmu, pebs_events_mask)); } +static inline bool intel_pmu_has_pebs(void) +{ + return x86_pmu.ds_pebs || x86_pmu.arch_pebs; +} + #else /* CONFIG_CPU_SUP_INTEL */ static inline void reserve_ds_buffers(void) diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index 49a4d442f3fc2..0dfa06722bab7 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -200,6 +200,8 @@ union cpuid10_edx { #define ARCH_PERFMON_EXT_LEAF 0x00000023 #define ARCH_PERFMON_NUM_COUNTER_LEAF 0x1 #define ARCH_PERFMON_ACR_LEAF 0x2 +#define ARCH_PERFMON_PEBS_CAP_LEAF 0x4 +#define ARCH_PERFMON_PEBS_COUNTER_LEAF 0x5 union cpuid35_eax { struct { @@ -210,7 +212,10 @@ union cpuid35_eax { unsigned int acr_subleaf:1; /* Events Sub-Leaf */ unsigned int events_subleaf:1; - unsigned int reserved:28; + /* arch-PEBS Sub-Leaves */ + unsigned int pebs_caps_subleaf:1; + unsigned int pebs_cnts_subleaf:1; + unsigned int reserved:26; } split; unsigned int full; };