[Intel-gfx] [PATCH 4/8] drm/i915/gt: Kick virtual siblings on timeslice out

[Tvrtko Ursulin]

On 18/05/2020 09:14, Chris Wilson wrote:
> If we decide to timeslice out the current virtual request, we will
> unsubmit it while it is still busy (ve->context.inflight == sibling[0]).
> If the virtual tasklet and then the other sibling tasklets run before we
> completely schedule out the active virtual request for the preemption,
> those other tasklets will see that the virtul request is still inflight
> on sibling[0] and leave it be. Therefore when we finally schedule-out
> the virtual request and if we see that we have passed it back to the
> virtual engine, reschedule the virtual tasklet so that it may be
> resubmitted on any of the siblings.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/gt/intel_lrc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
> index 80885ba87db5..05486e801a63 100644
> --- a/drivers/gpu/drm/i915/gt/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
> @@ -1402,7 +1402,7 @@ static void kick_siblings(struct i915_request *rq, struct intel_context *ce)
>   	struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
>   	struct i915_request *next = READ_ONCE(ve->request);
>   
> -	if (next && next->execution_mask & ~rq->execution_mask)
> +	if (next == rq || (next && next->execution_mask & ~rq->execution_mask))
>   		tasklet_hi_schedule(&ve->base.execlists.tasklet);
>   }
>   
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Regards,

Tvrtko