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Subject: Re: [tip:perf/core] Revert "sched, perf: Use a single callback
 into the scheduler"
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org,
        tglx@linutronix.de, jolsa@redhat.com
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References: <20120523111302.GC1638@m.brq.redhat.com>
	 <tip-ab0cce560ef177bdc7a8f73e9962be9d829a7b2c@git.kernel.org>
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Date: Wed, 23 May 2012 18:33:54 +0200
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On Wed, 2012-05-23 at 09:09 -0700, tip-bot for Jiri Olsa wrote:
>  > I rather liked we could do away with both that black-spot and
>  > clean up the code a little, but apparently people rely on it.
> 
Ingo noted that inherited counters already are active over the context
switch (due to the lazy switch optimization) and thus profile the
context switch cost.

Regular per-task counters not including this are therefore not
consistent.

So it would be good to find a way to fix the tracing fallout
differently. A well..