[PATCH] drm/sched: Declare entity idle only after HW submission

[Steven Price]

On 24/06/2021 15:08, Boris Brezillon wrote:
> The panfrost driver tries to kill in-flight jobs on FD close after
> destroying the FD scheduler entities. For this to work properly, we
> need to make sure the jobs popped from the scheduler entities have
> been queued at the HW level before declaring the entity idle, otherwise
> we might iterate over a list that doesn't contain those jobs.
> 
> Suggested-by: Lucas Stach <l.stach at pengutronix.de>
> Signed-off-by: Boris Brezillon <boris.brezillon at collabora.com>
> Cc: Lucas Stach <l.stach at pengutronix.de>

Reviewed-by: Steven Price <steven.price at arm.com>

> ---
>  drivers/gpu/drm/scheduler/sched_main.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 81496ae2602e..aa776ebe326a 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -811,10 +811,10 @@ static int drm_sched_main(void *param)
>  
>  		sched_job = drm_sched_entity_pop_job(entity);
>  
> -		complete(&entity->entity_idle);
> -
> -		if (!sched_job)
> +		if (!sched_job) {
> +			complete(&entity->entity_idle);
>  			continue;
> +		}
>  
>  		s_fence = sched_job->s_fence;
>  
> @@ -823,6 +823,7 @@ static int drm_sched_main(void *param)
>  
>  		trace_drm_run_job(sched_job, entity);
>  		fence = sched->ops->run_job(sched_job);
> +		complete(&entity->entity_idle);
>  		drm_sched_fence_scheduled(s_fence);
>  
>  		if (!IS_ERR_OR_NULL(fence)) {
>