From: Peter Zijlstra Date: Fri, 13 Mar 2009 15:43:47 +0000 (+0100) Subject: perf_counter: fix hrtimer sampling X-Git-Tag: firefly_0821_release~13973^2~474 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=039fc91e064b81c2820ff16c304be5aba35fd126;p=firefly-linux-kernel-4.4.55.git perf_counter: fix hrtimer sampling Impact: fix deadlock with perfstat Fix for the perfstat fubar.. We cannot unconditionally call hrtimer_cancel() without ever having done hrtimer_init() on the thing. Signed-off-by: Peter Zijlstra Orig-LKML-Reference: <1236959027.22447.149.camel@twins> Signed-off-by: Ingo Molnar --- diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 8d6ecfa64c0e..d6cc22271ef4 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1571,9 +1571,9 @@ static int cpu_clock_perf_counter_enable(struct perf_counter *counter) int cpu = raw_smp_processor_id(); atomic64_set(&hwc->prev_count, cpu_clock(cpu)); + hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + hwc->hrtimer.function = perf_swcounter_hrtimer; if (hwc->irq_period) { - hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - hwc->hrtimer.function = perf_swcounter_hrtimer; __hrtimer_start_range_ns(&hwc->hrtimer, ns_to_ktime(hwc->irq_period), 0, HRTIMER_MODE_REL, 0); @@ -1635,9 +1635,9 @@ static int task_clock_perf_counter_enable(struct perf_counter *counter) struct hw_perf_counter *hwc = &counter->hw; atomic64_set(&hwc->prev_count, task_clock_perf_counter_val(counter, 0)); + hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + hwc->hrtimer.function = perf_swcounter_hrtimer; if (hwc->irq_period) { - hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - hwc->hrtimer.function = perf_swcounter_hrtimer; __hrtimer_start_range_ns(&hwc->hrtimer, ns_to_ktime(hwc->irq_period), 0, HRTIMER_MODE_REL, 0);