Messages in this thread | | | Date | Wed, 15 Apr 2015 18:15:28 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH V2 1/6] perf,core: allow invalid context events to be part of sw/hw groups |
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On Wed, Apr 15, 2015 at 03:56:11AM -0400, Kan Liang wrote: > From: Kan Liang <kan.liang@intel.com> > > The pmu marked as perf_invalid_context don't have any state to switch on > context switch. Everything is global. So it is OK to be part of sw/hw > groups. > In sched_out/sched_in, del/add must be called, so the > perf_invalid_context event can be disabled/enabled accordingly during > context switch. The event count only be read when the event is already > sched_in. > > However group read doesn't work with mix events. > > For example, > perf record -e '{cycles,uncore_imc_0/cas_count_read/}:S' -a sleep 1 > It always gets EINVAL. > > This patch set intends to fix this issue. > perf record -e '{cycles,uncore_imc_0/cas_count_read/}:S' -a sleep 1 > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 0.202 MB perf.data (12 samples) ] > > This patch special case invalid context events and allow them to be part > of sw/hw groups.
I don't get it. What, Why?
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