[Intel-gfx] [PATCH 05/10] drm/i915: Track runtime spent in unreachable intel_contexts

[Chris Wilson]

Quoting Chris Wilson (2020-03-18 14:48:05)
> We do have a notification here for the context_retire we could listen to
> instead of listening to the request idling. If we use
> 
>         i915_sw_fence_await_active(&engines->fence,
>                                    &ce->active,
>                                    I915_ACTIVE_AWAIT_ALL);
> 
> instead, then the fence will not fire until the final barrier has
> executed.
> 
> Tada!

It's close. It's still strictly firing on the pulse request signaling,
which is currently not guaranteed to be after after the context_out.
Although we can arrange that with a sentinel.
-Chris