[Intel-gfx] [PATCH 3/5] drm/i915/gt: Only retire on the last breadcrumb if the last request

[Andi Shyti]

Hi Chris,

On Thu, Jan 07, 2021 at 10:17:22PM +0000, Chris Wilson wrote:
> We use the completion of the last active breadcrumb to retire the
> requests along a timeline. This is purely opportunistic as nothing
> guarantees that any particular timeline is terminated by a breadcrumb;
> except for the parking the engine. We explicitly add a breadcrumb to
> parking the engine so that we park quickly and do an explicit retire
> upon signaling to reduce the latency dramatically.
> 
> With scheduling, we anticipate retiring completed timelines as a matter
> of course. Performing the same action from inside the breadcrumbs is
> intended to provide similar functionality for legacy ringbuffer
> submission.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Reviewed-by: Andi Shyti <andi.shyti at intel.com>

Andi