Re: [PATCH] drm/sched: Re-queue run job worker when drm_sched_entity_pop_job() returns NULL

["Christian König" <christian.koenig@amd.com>]

Am 30.01.24 um 04:04 schrieb Matthew Brost:
> Rather then loop over entities until one with a ready job is found,
> re-queue the run job worker when drm_sched_entity_pop_job() returns NULL.
>
> Fixes: 6dbd9004a55 ("drm/sched: Drain all entities in DRM sched run job worker")
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>

Reviewed-by: Christian König <christian.koenig@amd.com>

> ---
>   drivers/gpu/drm/scheduler/sched_main.c | 15 +++++++++------
>   1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 8acbef7ae53d..7e90c9f95611 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -1178,21 +1178,24 @@ static void drm_sched_run_job_work(struct work_struct *w)
>   	struct drm_sched_entity *entity;
>   	struct dma_fence *fence;
>   	struct drm_sched_fence *s_fence;
> -	struct drm_sched_job *sched_job = NULL;
> +	struct drm_sched_job *sched_job;
>   	int r;
>   
>   	if (READ_ONCE(sched->pause_submit))
>   		return;
>   
>   	/* Find entity with a ready job */
> -	while (!sched_job && (entity = drm_sched_select_entity(sched))) {
> -		sched_job = drm_sched_entity_pop_job(entity);
> -		if (!sched_job)
> -			complete_all(&entity->entity_idle);
> -	}
> +	entity = drm_sched_select_entity(sched);
>   	if (!entity)
>   		return;	/* No more work */
>   
> +	sched_job = drm_sched_entity_pop_job(entity);
> +	if (!sched_job) {
> +		complete_all(&entity->entity_idle);
> +		drm_sched_run_job_queue(sched);
> +		return;
> +	}
> +
>   	s_fence = sched_job->s_fence;
>   
>   	atomic_add(sched_job->credits, &sched->credit_count);