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Subject: Re: REGRESSION: Performance regressions from switching
 anon_vma->lock to mutex
From: Tim Chen <tim.c.chen@linux.intel.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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On Wed, 2011-06-15 at 22:17 +0200, Ingo Molnar wrote:

> 
> have you used callgraph profiling (perf record -g) or flat profiling? 
> Flat profiling can be misleading when there's proxy work done.
> 

I've used callgraph profiling to see the call stack.

Tim

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