diff options
| author | Will Deacon <will.deacon@arm.com> | 2014-02-11 18:08:41 +0000 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2014-06-20 17:33:49 +0200 |
| commit | 22259d1fa4111413d7969bae6ad425fbc7fcf3e1 (patch) | |
| tree | bd59038532d912df4bcc70142437952d10097bc3 /arch | |
| parent | 4ce1386883095638c80190a37677b978e9650365 (diff) | |
| download | lwn-22259d1fa4111413d7969bae6ad425fbc7fcf3e1.tar.gz lwn-22259d1fa4111413d7969bae6ad425fbc7fcf3e1.zip | |
ARM: perf: hook up perf_sample_event_took around pmu irq handling
commit 5f5092e72cc25a6a5785308270e0085b2b2772cc upstream.
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>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'arch')
| -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 e186ee1e63f6..de5cd767e4df 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -303,11 +303,18 @@ static irqreturn_t armpmu_dispatch_irq(int irq, void *dev) struct arm_pmu *armpmu = (struct arm_pmu *) dev; struct platform_device *plat_device = armpmu->plat_device; struct arm_pmu_platdata *plat = dev_get_platdata(&plat_device->dev); + int ret; + u64 start_clock, finish_clock; + 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 |