From 984b838ce69c063a91b87550598ab7f3439dd94a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 10 Jul 2009 09:59:56 +0200 Subject: [PATCH] perf_counter: Clean up global vs counter enable Ingo noticed that both AMD and P6 call x86_pmu_disable_counter() on *_pmu_enable_counter(). This is because we rely on the side effect of that call to program the event config but not touch the EN bit. We change that for AMD by having enable_all() simply write the full config in, and for P6 by explicitly coding it. Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_counter.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c index c7cc6eac14ec..bed1c4c2f251 100644 --- a/arch/x86/kernel/cpu/perf_counter.c +++ b/arch/x86/kernel/cpu/perf_counter.c @@ -874,13 +874,13 @@ static void amd_pmu_enable_all(void) barrier(); for (idx = 0; idx < x86_pmu.num_counters; idx++) { + struct perf_counter *counter = cpuc->counters[idx]; u64 val; if (!test_bit(idx, cpuc->active_mask)) continue; - rdmsrl(MSR_K7_EVNTSEL0 + idx, val); - if (val & ARCH_PERFMON_EVENTSEL0_ENABLE) - continue; + + val = counter->hw.config; val |= ARCH_PERFMON_EVENTSEL0_ENABLE; wrmsrl(MSR_K7_EVNTSEL0 + idx, val); } @@ -1044,11 +1044,13 @@ intel_pmu_enable_fixed(struct hw_perf_counter *hwc, int __idx) static void p6_pmu_enable_counter(struct hw_perf_counter *hwc, int idx) { struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters); + u64 val; + val = hwc->config; if (cpuc->enabled) - x86_pmu_enable_counter(hwc, idx); - else - x86_pmu_disable_counter(hwc, idx); + val |= ARCH_PERFMON_EVENTSEL0_ENABLE; + + (void)checking_wrmsrl(hwc->config_base + idx, val); } @@ -1068,8 +1070,6 @@ static void amd_pmu_enable_counter(struct hw_perf_counter *hwc, int idx) if (cpuc->enabled) x86_pmu_enable_counter(hwc, idx); - else - x86_pmu_disable_counter(hwc, idx); } static int -- 2.20.1