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Subject: Re: spin_is_locked() broken for uniprocessor?
From: Peter Zijlstra <peterz@infradead.org>
To: Leon Woestenberg <leon.woestenberg@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, David Howells <dhowells@redhat.com>,
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Date: Wed, 19 Aug 2009 13:23:13 +0200
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On Wed, 2009-08-19 at 13:16 +0200, Leon Woestenberg wrote:
> Hello,
> 
> On Wed, Aug 19, 2009 at 12:53 PM, Alan Cox<alan@lxorguk.ukuu.org.uk> wrote:
> > On Wed, 19 Aug 2009 10:38:06 +0100
> >
> > in drivers because there is driver code that uses spin_is_locked() in
> > fairly sensible fashion when dealing with locking.
> >
> One use is to measure lock contention hits on a particular spin lock.
> 
> 
> However I wonder if there are tracing capabilities to measure lock
> contention on a particular lock?

lock_stat no good for you?