On Tue, May 27, 2014 at 10:00:12AM +0800, Weng Meiling wrote: > > Hi Dave, Stephane, Knut, Peter or Will, > > 14c63f17b1fde5a575a28e96547a22b451c71fb5 > perf: Drop sample rate when sampling is too slow > > e5302920da9ef23f9d19d4e9ac85704cc25bee7a > perf: Fix interrupt handler timing harness > > 723478c8a471403c53cf144999701f6e0c4bbd11 > perf: Enforce 1 as lower limit for perf_event_max_sample_rate > > 5f5092e72cc25a6a5785308270e0085b2b2772cc > ARM: perf: hook up perf_sample_event_took around pmu irq > > These patches look applicable to stable-3.10, these patches prevent > an interrupt storm when perf sampling is too slow on x86 and arm, > an interrupt storm may trigger softlockup. > > Patch e5302920da9e and 723478c8a471 are bug fix for 14c63f17b1fd. The > last one patch can't be applied directly, I've adjusted the context manually. > Thank you, I'm queuing this last patch for the 3.11 kernel as well (all the others were already present). Cheers, -- Luís > Now they were built successful for me. What do you think? > > the statistics of these patches： > Documentation/sysctl/kernel.txt | 26 +++++++++++ > arch/arm/kernel/perf_event.c | 11 ++++- > arch/x86/kernel/cpu/perf_event.c | 12 ++++- > include/linux/perf_event.h | 7 +++ > kernel/events/core.c | 94 +++++++++++++++++++++++++++++++++++++--- > kernel/sysctl.c | 10 +++++ > 6 files changed, 152 insertions(+), 8 deletions(-) > > > A detailed discussion can see the following link: > http://www.gossamer-threads.com/lists/linux/kernel/1839307?do=post_view_threaded#1839307 > > -------------------------------------------------------- > > From: Will Deacon <will.deacon@xxxxxxx> > Subject: [PATCH] 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@xxxxxxxxxx> > Signed-off-by: Will Deacon <will.deacon@xxxxxxx> > [wml: Backported to 3.10: context adjust ] > Signed-off-by: Weng Meiling <wengmeiling.weng@xxxxxxxxxx> > --- > arch/arm/kernel/perf_event.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c > index e19edc6..ace0ce8 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 > -- > 1.8.2.2 > > > > > > > -- > To unsubscribe from this list: send the line "unsubscribe stable" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html