[Intel-gfx] [PATCH 2/7] drm/i915: Unwrap top level fence-array

[Chris Wilson]

On Wed, May 03, 2017 at 10:00:02AM +0100, Tvrtko Ursulin wrote:
> 
> On 03/05/2017 00:41, Chris Wilson wrote:
> >By first unwrapping an incoming fence-array into its child fences, we
> >can simplify the internal branching, and so avoid triggering a potential
> 
> Potential something?

+ bug

> >in the next patch when not squashing the child fences on the same timeline.
> >
> >It will also have the advantage of keeping the (top-level) fence arrays
> >out of any fence/timeline caching since these are unordered timelines
> >but with a random context id.
> 
> Is it a random context id or just one not associated with any user
> contexts and not ever exported to userspace?

Yes, I was using random as a derogative ;) It has an unpredictable
one-off id, that is never repeated (this millenia, at least) and not tied
to anything real, either userspace or hw. We could reduce all such beasts
to a single unordered timeline...
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre