diff options
| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2010-03-08 17:51:33 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-03-10 13:22:31 +0100 |
| commit | 71e2d2828046133ed985696a02e2e1499ca0bfb8 (patch) | |
| tree | 0c180d1da4be85254e59001420ff9c558b38e205 | |
| parent | c08053e627d23490a03431285b78b7a5b617fbad (diff) | |
perf, x86: Avoid double disable on throttle vs ioctl(PERF_IOC_DISABLE)
Calling ioctl(PERF_EVENT_IOC_DISABLE) on a thottled counter would result
in a double disable, cure this by using x86_pmu_{start,stop} for
throttle/unthrottle and teach x86_pmu_stop() to check ->active_mask.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 20 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel.c | 2 |
2 files changed, 7 insertions, 15 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index 9757b96f15f5..b68c4fb7a944 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -983,14 +983,8 @@ static int x86_pmu_start(struct perf_event *event) static void x86_pmu_unthrottle(struct perf_event *event) { - struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); - struct hw_perf_event *hwc = &event->hw; - - if (WARN_ON_ONCE(hwc->idx >= X86_PMC_IDX_MAX || - cpuc->events[hwc->idx] != event)) - return; - - x86_pmu.enable(event); + int ret = x86_pmu_start(event); + WARN_ON_ONCE(ret); } void perf_event_print_debug(void) @@ -1050,11 +1044,9 @@ static void x86_pmu_stop(struct perf_event *event) struct hw_perf_event *hwc = &event->hw; int idx = hwc->idx; - /* - * Must be done before we disable, otherwise the nmi handler - * could reenable again: - */ - __clear_bit(idx, cpuc->active_mask); + if (!__test_and_clear_bit(idx, cpuc->active_mask)) + return; + x86_pmu.disable(event); /* @@ -1123,7 +1115,7 @@ static int x86_pmu_handle_irq(struct pt_regs *regs) continue; if (perf_event_overflow(event, 1, &data, regs)) - x86_pmu.disable(event); + x86_pmu_stop(event); } if (handled) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index d87421c3f55b..84bfde64a337 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -774,7 +774,7 @@ again: data.period = event->hw.last_period; if (perf_event_overflow(event, 1, &data, regs)) - intel_pmu_disable_event(event); + x86_pmu_stop(event); } intel_pmu_ack_status(ack); |