From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Vetter <daniel@ffwll.ch>
Subject: Re: [PATCH 2/5] drm/i915: make waiting trace events
 more useful
Date: Wed, 2 May 2012 23:56:19 +0200
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To: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>, intel-gfx@lists.freedesktop.org
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On Wed, May 02, 2012 at 11:36:15PM +0200, Daniel Vetter wrote:
> On Wed, May 02, 2012 at 10:22:33PM +0100, Chris Wilson wrote:
> > On Wed, 2 May 2012 23:12:36 +0200, Daniel Vetter <daniel@ffwll.ch> wrote:
> > > For consistency I guess we can ditch the dev parameter (and even then, the
> > > ring would uniquely identify the device). Also, I guess you need to
> > > explicitly pass in blocking, because mutex_is_locked is rather racy -
> > > someone else could hold the mutex while we're waiting in a non-blocking
> > > fashion.
> > 
> > Meh, I suggested the race - I'd rather have a moment of confusion
> > reading the trace than reading the code in 6 months time.
> 
> Ok, I see the problem and agree, let's have it slightly racy ...

I've forgotten to add: Ben, please add the reasons why we decided to go
with the racy variant to the commit messages, that kind of stuff is really
important (otherwise the patch simply looks buggy).
-Daniel
-- 
Daniel Vetter
Mail: daniel@ffwll.ch
Mobile: +41 (0)79 365 57 48