Messages in this thread |  | | | Date | Tue, 7 Feb 2012 11:49:52 +0100 | | From | Ingo Molnar <> | | Subject | Re: [PATCH] perf: fix assertion failure in x86_pmu_start() |
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* Stephane Eranian <eranian@google.com> wrote:
> On Tue, Feb 7, 2012 at 11:25 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote: > > Le mardi 07 février 2012 à 09:41 +0100, Ingo Molnar a écrit : > > > >> Were these messages introduced by: > >> > >> e050e3f0a71b: perf: Fix broken interrupt rate throttling > >> > >> as well? > >> > >> In any case I'm holding off on applying the patch before this is > >> resolved. > > > > Reverting e050e3f0a71b solves all my problems, no more warnings. > > > > $ perf record -a -g hackbench 10 thread 4000 > > Running with 10*40 (== 400) tasks. > > Time: 13.181 > > [ perf record: Woken up 59 times to write data ] > > [ perf record: Captured and wrote 16.874 MB perf.data (~737228 samples) > > ] > > > > $ perf record -a -g hackbench 10 thread 4000 > > Running with 10*40 (== 400) tasks. > > Time: 13.124 > > [ perf record: Woken up 61 times to write data ] > > [ perf record: Captured and wrote 16.533 MB perf.data (~722349 samples) > > ] > > > > What system is this running on? > The problem is that without e050e3f0a71b interrupt throttling does not work.
Fixes are not supposed to regress, so if we cannot resolve this within a couple of days we'll have to revert e050e3f0a71b and re-try it later.
> I think the key difference is that without the patch, > frequency adjustment happens with the PMU completely stopped > whereas with my patch it does not. I suspect this may be the > issue. I can rework the patch to disable the PMU completely > while retaining the same workflow.
Would be nice to try that.
Thanks,
Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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