[Intel-gfx] [PATCH 3/8] drm/i915: Replace engine->timeline with a plain list

[Chris Wilson]

Quoting Mika Kuoppala (2019-06-14 16:50:33)
> Chris Wilson <chris at chris-wilson.co.uk> writes:
> > @@ -254,6 +254,7 @@ static bool i915_request_retire(struct i915_request *rq)
> >       intel_context_unpin(rq->hw_context);
> >  
> >       i915_request_remove_from_client(rq);
> > +     list_del(&rq->link);
> 
> This is now unguarded. and the timeline mutex is not here
> to help either.

It is guarded by the caller to i915_request_retire, we can only retire
under the same lock as we construct requests. Currently that is
struct_mutex with the big switcheroo coming at the end.
-Chris