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Subject: Re: [PATCH] perf_events: fix bogus warn_on(_once) in 
 perf_prepare_sample()
From: Peter Zijlstra <peterz@infradead.org>
To: Stephane Eranian <eranian@google.com>
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Date: Thu, 08 Apr 2010 23:12:19 +0200
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On Thu, 2010-04-08 at 23:08 +0200, Stephane Eranian wrote:
> 
> > There's various things that do indeed rely on the perf buffer to always
> > be u64 aligned, so this warning isn't bogus at all.
> >
> I assume this has to do with the wrap-around detection.

Nah, mostly dealing with architectures that don't do well with unaligned
accesses.