From ad0e6cfe2a2a61d7b5530188e571d508146cb43b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sat, 6 Mar 2010 19:49:06 +0100 Subject: [PATCH] perf, x86: Fix silly bug in intel_pmu_pebs_{enable,disable} We need to use the actual cpuc->pebs_enabled value, not a local copy for the changes to take effect. Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: paulus@samba.org Cc: eranian@google.com Cc: robert.richter@amd.com Cc: fweisbec@gmail.com LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event_intel_ds.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c index b4680daecf1..242369488e7 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c @@ -333,11 +333,10 @@ static void intel_pmu_pebs_enable(struct perf_event *event) { struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); struct hw_perf_event *hwc = &event->hw; - u64 val = cpuc->pebs_enabled; hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT; - val |= 1ULL << hwc->idx; + cpuc->pebs_enabled |= 1ULL << hwc->idx; WARN_ON_ONCE(cpuc->enabled); if (x86_pmu.intel_cap.pebs_trap) @@ -348,11 +347,10 @@ static void intel_pmu_pebs_disable(struct perf_event *event) { struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); struct hw_perf_event *hwc = &event->hw; - u64 val = cpuc->pebs_enabled; - val &= ~(1ULL << hwc->idx); + cpuc->pebs_enabled &= ~(1ULL << hwc->idx); if (cpuc->enabled) - wrmsrl(MSR_IA32_PEBS_ENABLE, val); + wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled); hwc->config |= ARCH_PERFMON_EVENTSEL_INT; -- 2.20.1