Messages in this thread | | | Date | Fri, 15 Nov 2013 11:13:27 +0100 | Subject | Re: [BUG] perf stat: explicit grouping yields unexpected results | From | Stephane Eranian <> |
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On Fri, Nov 15, 2013 at 11:05 AM, Peter Zijlstra <peterz@infradead.org> wrote: > On Fri, Nov 15, 2013 at 07:34:57AM +0100, Ingo Molnar wrote: >> Btw., does the kernel side currently support discovery of such >> impossible group scheduling constraints at group setup time? > > Up to a point. > It is only looking at the group itself not the overall condition of the system, e.g., the other HT thread is case of shared resources. I think all it guarantees is that if the events in the group are compatible with each other. And I think it covers the case where the events use different counters but the same shared resource, e.g., offcore_response on Intel X86.
>> If not >> then it probably should and it should reject them straight away. > > We do I think, for the case where its obvious it can never fit. > > That said, if you have a pinned cpu event, it all comes apart.
You mean in the group?
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