[Intel-gfx] [PATCH] drm/i915: Fix waiting for engines to idle

[Chris Wilson]

On Tue, May 23, 2017 at 11:09:17AM +0100, Chris Wilson wrote:
> On Tue, May 23, 2017 at 10:36:34AM +0100, Chris Wilson wrote:
> > On Tue, May 23, 2017 at 10:19:31AM +0100, Tvrtko Ursulin wrote:
> > > From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> > > 
> > > Waiting for engines needs to happen even in the non-debug builds
> > > so it is incorrect to wrap it in a GEM_WARN_ON.
> > > 
> > > Call it unconditionally and add GEM_WARN so that the debug
> > > warning can still be emitted when things go bad.
> > > 
> > > Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> > > Fixes: 25112b64b3d2 ("drm/i915: Wait for all engines to be idle as part of i915_gem_wait_for_idle()")
> > 
> > I would also say 
> > Fixes: 7a453fb82f86 ("drm/i915: Remove redudant wait for each engine to idle from seqno wrap")
> > as that's the patch that assumes wait_for_idle included the wait on
> > engines.
> 
> Hmm, actually that was only to prevent a DEBUG_GEM failure so not a
> relevant citation for fixes?

And actually, this if for debug only code so the Fixes 25112b64b3d2 is
wrong as well as we as introducing a change in behaviour (making the
debug only code run all the time) with no urgent need for backporting.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre