From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roland Dreier <roland@kernel.org>
Subject: Re: perf for analyzing userspace contention
Date: Fri, 14 Oct 2011 00:21:06 -0700
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To: "Maucci, Cyrille" <cyrille.maucci@hp.com>
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On Thu, Oct 13, 2011 at 11:58 PM, Maucci, Cyrille <cyrille.maucci@hp.com> wrote:
> So are those mutexes acquired/released from different call sites or from one single generic function of yours like LOCK/UNLOCK and the mutex is passed as a param?

I have lots of code paths taking lots of different classes of locks.

My problem is I don't know what to ask perf for to see if I have a mutex that
is heavily contended, and so some threads are spending a lot of time asleep
waiting to acquire it.  As I said, this is probably pretty basic
stuff, but I'm not
usually much of a userspace guy...

Thanks,
  Roland