[Intel-gfx] [PATCH 8/8] drm/i915: Keep track of reserved execlist ports

[Chris Wilson]

Quoting Mika Kuoppala (2017-09-12 09:36:18)
> To further enchance port processing, keep track of
> reserved ports. This way we can iterate only the used subset
> of port space. Note that we lift the responsibility of
> execlists_submit_request() to inspect hw availability and
> always do dequeuing. This is to ensure that only the irq
> handler will be responsible for keeping track of available ports.

Hmm, gut feeling is that tracking the tail instead of count is more
intuitive, especially for dequeue.
-Chris