Messages in this thread | | | Date | Fri, 20 Jul 2012 17:34:46 -0600 | From | David Ahern <> | Subject | Re: perf with precise attribute kills all KVM based VMs |
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On 7/11/12 1:10 AM, Gleb Natapov wrote: > Looks like Avi is right about the overshoot. Can you test something like this? > > diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c > index 166546e..5fb371a 100644 > --- a/arch/x86/kernel/cpu/perf_event_intel.c > +++ b/arch/x86/kernel/cpu/perf_event_intel.c > @@ -1374,8 +1374,11 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr) > arr[0].msr = MSR_CORE_PERF_GLOBAL_CTRL; > arr[0].host = x86_pmu.intel_ctrl & ~cpuc->intel_ctrl_guest_mask; > arr[0].guest = x86_pmu.intel_ctrl & ~cpuc->intel_ctrl_host_mask; > + arr[1].msr = MSR_IA32_PEBS_ENABLE; > + arr[1].host = cpuc->pebs_enabled; > + arr[1].guest = 0; > + *nr = 2; > > - *nr = 1; > return arr; > }
Tested-by: David Ahern <dsahern@gmail.com>
Peter's patch is required as well. It's the combination that fixes the problem.
David
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