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| author | Will Deacon <will.deacon@arm.com> | 2014-02-11 18:08:41 +0000 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2014-02-21 11:11:21 +0000 |
| commit | 5f5092e72cc25a6a5785308270e0085b2b2772cc (patch) | |
| tree | a3f5d15b978418cd29200a95d7abd33440a16577 /arch/arm/kernel/perf_event.c | |
| parent | d84c47837d800c0db1c9f2015a1565504417f812 (diff) | |
| download | linux-stable-5f5092e72cc25a6a5785308270e0085b2b2772cc.tar.gz linux-stable-5f5092e72cc25a6a5785308270e0085b2b2772cc.tar.bz2 linux-stable-5f5092e72cc25a6a5785308270e0085b2b2772cc.zip | |
ARM: perf: hook up perf_sample_event_took around pmu irq handling
Since we indirect all of our PMU IRQ handling through a dispatcher, it's
trivial to hook up perf_sample_event_took to prevent applications such
as oprofile from generating interrupt storms due to an unrealisticly
low sample period.
Reported-by: Robert Richter <rric@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm/kernel/perf_event.c')
| -rw-r--r-- | arch/arm/kernel/perf_event.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 361a1aaee7c8..a6bc431cde70 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -302,6 +302,8 @@ static irqreturn_t armpmu_dispatch_irq(int irq, void *dev) struct arm_pmu *armpmu; struct platform_device *plat_device; struct arm_pmu_platdata *plat; + int ret; + u64 start_clock, finish_clock; if (irq_is_percpu(irq)) dev = *(void **)dev; @@ -309,10 +311,15 @@ static irqreturn_t armpmu_dispatch_irq(int irq, void *dev) plat_device = armpmu->plat_device; plat = dev_get_platdata(&plat_device->dev); + start_clock = sched_clock(); if (plat && plat->handle_irq) - return plat->handle_irq(irq, dev, armpmu->handle_irq); + ret = plat->handle_irq(irq, dev, armpmu->handle_irq); else - return armpmu->handle_irq(irq, dev); + ret = armpmu->handle_irq(irq, dev); + finish_clock = sched_clock(); + + perf_sample_event_took(finish_clock - start_clock); + return ret; } static void |