[Intel-gfx] [PATCH 06/42] drm/i915: Support asynchronous waits on struct fence from i915_gem_request

[Chris Wilson]

On Fri, Oct 07, 2016 at 05:16:17PM +0100, Tvrtko Ursulin wrote:
> 
> On 07/10/2016 17:12, Chris Wilson wrote:
> >>2. Can child be another array?
> >Yes, but we don't want to recurse (or at least need to bound the
> >recursion).
> 
> In that case could the array have been created in the signal_on_any
> mode and how would we handle that?

Hmm. Not along our paths, I think. The only fence-array we have are from
sync-file which are signal-on-all (except... in the case of where it
wraps a single fence, that fence could be a composite). signal-on-any is
icky, to be complete we should not decompose it into its elements -
however, whether or not a fence-array is operating in signal_on_any mode
is not stored. So at the moment, the best I can do is offer a comment.

The only user of it at the moment is amdgpu waiting for the first of
many VM manager to become available, not something we'll see
immediately via sync-file.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre