[Intel-gfx] [PATCH 5/5] drm/i915: Wait for object idle without locks in atomic_commit.

[Chris Wilson]

On Mon, Nov 02, 2015 at 02:13:48PM +0100, Maarten Lankhorst wrote:
> Op 29-10-15 om 01:30 schreef Matt Roper:
> > On Wed, Sep 23, 2015 at 01:27:12PM +0200, Maarten Lankhorst wrote:
> >> diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
> >> index 444542696a2c..1b18cc6bdbd6 100644
> >> --- a/drivers/gpu/drm/i915/intel_overlay.c
> >> +++ b/drivers/gpu/drm/i915/intel_overlay.c
> >> @@ -749,7 +749,11 @@ static int intel_overlay_do_put_image(struct intel_overlay *overlay,
> >>  	if (ret != 0)
> >>  		return ret;
> >>  
> >> -	ret = i915_gem_object_pin_to_display_plane(new_bo, 0, NULL, NULL,
> >> +	ret = i915_gem_object_wait_rendering(new_bo, true);
> > Again, I'm not super familiar with GEM internals...can this be a
> > behavior change from the previous code?  Originally the pin_to_display
> > plane function would have passed (obj->base.pending_write_domain == 0)
> > as the second parameter here (readonly), but you're unconditionally
> > passing true.  Can there not be pending writes against this object?
> I don't think it would be important in the case of overlays. But maybe I should
> just replace it with a call to i915_gem_object_sync and wait for full object idle.

Technically it removes a call to set-cache, acquiring a GGTT offset and
pinning it, and a final set-to-gtt. 

Quite a major and broken change.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre