diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c index 242369488e72..1bfd59beb658 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c @@ -472,20 +472,39 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs) struct pt_regs regs; int n; - if (!event || !ds || !x86_pmu.pebs) + if (!ds || !x86_pmu.pebs) return; at = (struct pebs_record_core *)(unsigned long)ds->pebs_buffer_base; top = (struct pebs_record_core *)(unsigned long)ds->pebs_index; - if (top <= at) + /* + * Whatever else happens, drain the thing + */ + ds->pebs_index = ds->pebs_buffer_base; + + if (!test_bit(0, cpuc->active_mask)) return; - ds->pebs_index = ds->pebs_buffer_base; + WARN_ON_ONCE(!event); + + if (!event->attr.precise) + return; + + n = top - at; + if (n <= 0) + return; if (!intel_pmu_save_and_restart(event)) return; + /* + * Should not happen, we program the threshold at 1 and do not + * set a reset value. + */ + WARN_ON_ONCE(n > 1); + at += n - 1; + perf_sample_data_init(&data, 0); data.period = event->hw.last_period; @@ -495,14 +514,6 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs) data.raw = &raw; } - n = top - at; - - /* - * Should not happen, we program the threshold at 1 and do not - * set a reset value. - */ - WARN_ON_ONCE(n > 1); - /* * We use the interrupt regs as a base because the PEBS record * does not contain a full regs set, specifically it seems to @@ -545,12 +556,11 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs) at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base; top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index; - if (top <= at) - return; - ds->pebs_index = ds->pebs_buffer_base; n = top - at; + if (n <= 0) + return; /* * Should not happen, we program the threshold at 1 and do not