diff options
Diffstat (limited to 'arch/x86/events')
-rw-r--r-- | arch/x86/events/core.c | 15 | ||||
-rw-r--r-- | arch/x86/events/intel/core.c | 12 | ||||
-rw-r--r-- | arch/x86/events/intel/ds.c | 117 | ||||
-rw-r--r-- | arch/x86/events/perf_event.h | 2 |
4 files changed, 122 insertions, 24 deletions
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 02e547f9ca3f..655a65eaf105 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1155,16 +1155,13 @@ int x86_perf_event_set_period(struct perf_event *event) per_cpu(pmc_prev_left[idx], smp_processor_id()) = left; - if (!(hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) || - local64_read(&hwc->prev_count) != (u64)-left) { - /* - * The hw event starts counting from this event offset, - * mark it to be able to extra future deltas: - */ - local64_set(&hwc->prev_count, (u64)-left); + /* + * The hw event starts counting from this event offset, + * mark it to be able to extra future deltas: + */ + local64_set(&hwc->prev_count, (u64)-left); - wrmsrl(hwc->event_base, (u64)(-left) & x86_pmu.cntval_mask); - } + wrmsrl(hwc->event_base, (u64)(-left) & x86_pmu.cntval_mask); /* * Due to erratum on certan cpu we need diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 6f353a874178..815039327932 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2066,16 +2066,23 @@ static int intel_pmu_handle_irq(struct pt_regs *regs) int bit, loops; u64 status; int handled; + int pmu_enabled; cpuc = this_cpu_ptr(&cpu_hw_events); /* + * Save the PMU state. + * It needs to be restored when leaving the handler. + */ + pmu_enabled = cpuc->enabled; + /* * No known reason to not always do late ACK, * but just in case do it opt-in. */ if (!x86_pmu.late_ack) apic_write(APIC_LVTPC, APIC_DM_NMI); intel_bts_disable_local(); + cpuc->enabled = 0; __intel_pmu_disable_all(); handled = intel_pmu_drain_bts_buffer(); handled += intel_bts_interrupt(); @@ -2173,7 +2180,8 @@ again: done: /* Only restore PMU state when it's active. See x86_pmu_disable(). */ - if (cpuc->enabled) + cpuc->enabled = pmu_enabled; + if (pmu_enabled) __intel_pmu_enable_all(0, true); intel_bts_enable_local(); @@ -3019,7 +3027,7 @@ hsw_get_event_constraints(struct cpu_hw_events *cpuc, int idx, * Therefore the effective (average) period matches the requested period, * despite coarser hardware granularity. */ -static unsigned bdw_limit_period(struct perf_event *event, unsigned left) +static u64 bdw_limit_period(struct perf_event *event, u64 left) { if ((event->hw.config & INTEL_ARCH_EVENT_MASK) == X86_CONFIG(.event=0xc0, .umask=0x01)) { diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index 8e7a3f1df3a5..f26e26e4d84f 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -1110,6 +1110,7 @@ static void setup_pebs_sample_data(struct perf_event *event, if (pebs == NULL) return; + regs->flags &= ~PERF_EFLAGS_EXACT; sample_type = event->attr.sample_type; dsrc = sample_type & PERF_SAMPLE_DATA_SRC; @@ -1154,7 +1155,6 @@ static void setup_pebs_sample_data(struct perf_event *event, */ *regs = *iregs; regs->flags = pebs->flags; - set_linear_ip(regs, pebs->ip); if (sample_type & PERF_SAMPLE_REGS_INTR) { regs->ax = pebs->ax; @@ -1190,13 +1190,22 @@ static void setup_pebs_sample_data(struct perf_event *event, #endif } - if (event->attr.precise_ip > 1 && x86_pmu.intel_cap.pebs_format >= 2) { - regs->ip = pebs->real_ip; - regs->flags |= PERF_EFLAGS_EXACT; - } else if (event->attr.precise_ip > 1 && intel_pmu_pebs_fixup_ip(regs)) - regs->flags |= PERF_EFLAGS_EXACT; - else - regs->flags &= ~PERF_EFLAGS_EXACT; + if (event->attr.precise_ip > 1) { + /* Haswell and later have the eventing IP, so use it: */ + if (x86_pmu.intel_cap.pebs_format >= 2) { + set_linear_ip(regs, pebs->real_ip); + regs->flags |= PERF_EFLAGS_EXACT; + } else { + /* Otherwise use PEBS off-by-1 IP: */ + set_linear_ip(regs, pebs->ip); + + /* ... and try to fix it up using the LBR entries: */ + if (intel_pmu_pebs_fixup_ip(regs)) + regs->flags |= PERF_EFLAGS_EXACT; + } + } else + set_linear_ip(regs, pebs->ip); + if ((sample_type & PERF_SAMPLE_ADDR) && x86_pmu.intel_cap.pebs_format >= 1) @@ -1263,17 +1272,84 @@ get_next_pebs_record_by_bit(void *base, void *top, int bit) return NULL; } +/* + * Special variant of intel_pmu_save_and_restart() for auto-reload. + */ +static int +intel_pmu_save_and_restart_reload(struct perf_event *event, int count) +{ + struct hw_perf_event *hwc = &event->hw; + int shift = 64 - x86_pmu.cntval_bits; + u64 period = hwc->sample_period; + u64 prev_raw_count, new_raw_count; + s64 new, old; + + WARN_ON(!period); + + /* + * drain_pebs() only happens when the PMU is disabled. + */ + WARN_ON(this_cpu_read(cpu_hw_events.enabled)); + + prev_raw_count = local64_read(&hwc->prev_count); + rdpmcl(hwc->event_base_rdpmc, new_raw_count); + local64_set(&hwc->prev_count, new_raw_count); + + /* + * Since the counter increments a negative counter value and + * overflows on the sign switch, giving the interval: + * + * [-period, 0] + * + * the difference between two consequtive reads is: + * + * A) value2 - value1; + * when no overflows have happened in between, + * + * B) (0 - value1) + (value2 - (-period)); + * when one overflow happened in between, + * + * C) (0 - value1) + (n - 1) * (period) + (value2 - (-period)); + * when @n overflows happened in between. + * + * Here A) is the obvious difference, B) is the extension to the + * discrete interval, where the first term is to the top of the + * interval and the second term is from the bottom of the next + * interval and C) the extension to multiple intervals, where the + * middle term is the whole intervals covered. + * + * An equivalent of C, by reduction, is: + * + * value2 - value1 + n * period + */ + new = ((s64)(new_raw_count << shift) >> shift); + old = ((s64)(prev_raw_count << shift) >> shift); + local64_add(new - old + count * period, &event->count); + + perf_event_update_userpage(event); + + return 0; +} + static void __intel_pmu_pebs_event(struct perf_event *event, struct pt_regs *iregs, void *base, void *top, int bit, int count) { + struct hw_perf_event *hwc = &event->hw; struct perf_sample_data data; struct pt_regs regs; void *at = get_next_pebs_record_by_bit(base, top, bit); - if (!intel_pmu_save_and_restart(event) && - !(event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)) + if (hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) { + /* + * Now, auto-reload is only enabled in fixed period mode. + * The reload value is always hwc->sample_period. + * May need to change it, if auto-reload is enabled in + * freq mode later. + */ + intel_pmu_save_and_restart_reload(event, count); + } else if (!intel_pmu_save_and_restart(event)) return; while (count > 1) { @@ -1325,8 +1401,11 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs) return; n = top - at; - if (n <= 0) + if (n <= 0) { + if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD) + intel_pmu_save_and_restart_reload(event, 0); return; + } __intel_pmu_pebs_event(event, iregs, at, top, 0, n); } @@ -1349,8 +1428,22 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs) ds->pebs_index = ds->pebs_buffer_base; - if (unlikely(base >= top)) + if (unlikely(base >= top)) { + /* + * The drain_pebs() could be called twice in a short period + * for auto-reload event in pmu::read(). There are no + * overflows have happened in between. + * It needs to call intel_pmu_save_and_restart_reload() to + * update the event->count for this case. + */ + for_each_set_bit(bit, (unsigned long *)&cpuc->pebs_enabled, + x86_pmu.max_pebs_events) { + event = cpuc->events[bit]; + if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD) + intel_pmu_save_and_restart_reload(event, 0); + } return; + } for (at = base; at < top; at += x86_pmu.pebs_record_size) { struct pebs_record_nhm *p = at; diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index bcbb1d2ae10b..f3563179290b 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -548,7 +548,7 @@ struct x86_pmu { struct x86_pmu_quirk *quirks; int perfctr_second_write; bool late_ack; - unsigned (*limit_period)(struct perf_event *event, unsigned l); + u64 (*limit_period)(struct perf_event *event, u64 l); /* * sysfs attrs |