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Subject: Re: [RFC][PATCH 3/9] perf: export registerred pmus via sysfs
From: Peter Zijlstra <peterz@infradead.org>
To: Borislav Petkov <bp@amd64.org>
Cc: Ingo Molnar <mingo@elte.hu>, Lin Ming <ming.m.lin@intel.com>,
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Date: Tue, 11 May 2010 16:25:15 +0200
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On Tue, 2010-05-11 at 16:15 +0200, Borislav Petkov wrote:
> Another point I have is that MCEs don't need pmus so we should consider
> having the ability to decouple events from pmus.

Strictly speaking tracepoints are software events, which run off of a
software 'pmu'. So no, we can't decouple, they need a 'pmu' context.

> What you basically want to have is a tracepoint which is "persistent,"
> as Ingo suggested earlier, and it buffers MCEs occurring at any time
> into a ring buffer until a userspace daemon or similar sucks that data
> out for processing (critical stuff is handled differently, of course).
> And this should work on any x86 hw supporting MCA without hw perf
> monitoring features. 

Try building x86 without perf hw support :/