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Subject: Re: [GIT PULL] perf crash fix
From: Peter Zijlstra <peterz@infradead.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       Paul Mackerras <paulus@samba.org>,
       Stephane Eranian <eranian@google.com>
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Date: Thu, 03 Jun 2010 14:40:31 +0200
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On Thu, 2010-06-03 at 14:35 +0200, Frederic Weisbecker wrote:

> I wanted to, but I thought we could avoid two indirect calls on each
> ticks and I was also afraid of breaking start/stop original semantics,
> more especially the role of perf_event_stop/start

Right, so you lost the fallback to ->enable/->disable, which would break
hardware PMU implementations that didn't actually implement
->start/->stop (pretty much all of them except x86).