Messages in this thread | | | Date | Wed, 15 May 2013 16:20:46 +0200 | Subject | Re: [PATCH 1/3] perf, x86: Blacklist all MEM_*_RETIRED events for IVB | From | Stephane Eranian <> |
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Hi,
Based on our testing, it appears the corruption occurs only when the MEM_* events are used and only on the sibling counter. In other words, if HT0 has MEM_* in cntr0, then HT1 cntr0 cannot be used, otherwise whatever is there may get corrupted. So I think we could enhance Andi's initial patch to handle this case instead of blacklist those events. They are very important events.
On Fri, May 3, 2013 at 7:00 PM, Peter Zijlstra <peterz@infradead.org> wrote: > On Fri, May 03, 2013 at 07:35:07AM -0700, Andi Kleen wrote: >> On Fri, May 03, 2013 at 02:11:23PM +0200, Peter Zijlstra wrote: >> > Errata BV98 states that all MEM_*_RETIRED events corrupt the counter >> > value of the SMT sibling's counters. Blacklist these events >> >> I disagree with this patch. This is just overkill and not needed >> at all. > > Then give me a patch that both completely describes the problem and ensures > isolation so that no counters get corrupted (and isn't too invasive). > > So far you've failed on both counts. > >
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