[PATCH 1/2] drm/scheduler: add a current job field to scheduler

[Koenig, Christian]

Am 18.09.2018 um 18:17 schrieb Nayan Deshmukh:
> Which points to the job running on the hardware. This is
> useful when we need to access the currently executing job
> from the scheduler.

That should be identical to 
list_first_entry_or_null(&sched->ring_mirror_list), doesn't it?

Regards,
Christian.

>
> Signed-off-by: Nayan Deshmukh <nayan26deshmukh at gmail.com>
> ---list_first_entry_or_null(&sched->ring_mirror_list
>
>   drivers/gpu/drm/scheduler/sched_main.c | 17 +++++++++++------
>   include/drm/gpu_scheduler.h            |  2 ++
>   2 files changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 9ca741f3a0bc..0e6ccc8243db 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -189,6 +189,7 @@ static void drm_sched_job_finish(struct work_struct *work)
>   	struct drm_sched_job *s_job = container_of(work, struct drm_sched_job,
>   						   finish_work);
>   	struct drm_gpu_scheduler *sched = s_job->sched;
> +	struct drm_sched_job *next;
>   
>   	/*
>   	 * Canceling the timeout without removing our job from the ring mirror
> @@ -201,10 +202,10 @@ static void drm_sched_job_finish(struct work_struct *work)
>   
>   	spin_lock(&sched->job_list_lock);
>   	/* queue TDR for next job */
> +	next = list_next_entry(s_job, node);
> +	sched->curr_job = next;
>   	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
>   	    !list_is_last(&s_job->node, &sched->ring_mirror_list)) {
> -		struct drm_sched_job *next = list_next_entry(s_job, node);
> -
>   		if (!dma_fence_is_signaled(&next->s_fence->finished))
>   			schedule_delayed_work(&next->work_tdr, sched->timeout);
>   	}
> @@ -233,10 +234,12 @@ static void drm_sched_job_begin(struct drm_sched_job *s_job)
>   
>   	spin_lock(&sched->job_list_lock);
>   	list_add_tail(&s_job->node, &sched->ring_mirror_list);
> -	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
> -	    list_first_entry_or_null(&sched->ring_mirror_list,
> -				     struct drm_sched_job, node) == s_job)
> -		schedule_delayed_work(&s_job->work_tdr, sched->timeout);
> +	if (list_first_entry_or_null(&sched->ring_mirror_list,
> +				struct drm_sched_job, node) == s_job) {
> +		if (sched->timeout != MAX_SCHEDULE_TIMEOUT)
> +			schedule_delayed_work(&s_job->work_tdr, sched->timeout);
> +		sched->curr_job = s_job;
> +	}
>   	spin_unlock(&sched->job_list_lock);
>   }
>   
> @@ -316,6 +319,8 @@ void drm_sched_job_recovery(struct drm_gpu_scheduler *sched)
>   					 struct drm_sched_job, node);
>   	if (s_job && sched->timeout != MAX_SCHEDULE_TIMEOUT)
>   		schedule_delayed_work(&s_job->work_tdr, sched->timeout);
> +	if (s_job)
> +		sched->curr_job = s_job;
>   
>   	list_for_each_entry_safe(s_job, tmp, &sched->ring_mirror_list, node) {
>   		struct drm_sched_fence *s_fence = s_job->s_fence;
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index daec50f887b3..07e776b1ca42 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -252,6 +252,7 @@ struct drm_sched_backend_ops {
>    * @timeout: the time after which a job is removed from the scheduler.
>    * @name: name of the ring for which this scheduler is being used.
>    * @sched_rq: priority wise array of run queues.
> + * @curr_job: points to the job currently running on the hardware
>    * @wake_up_worker: the wait queue on which the scheduler sleeps until a job
>    *                  is ready to be scheduled.
>    * @job_scheduled: once @drm_sched_entity_do_release is called the scheduler
> @@ -274,6 +275,7 @@ struct drm_gpu_scheduler {
>   	long				timeout;
>   	const char			*name;
>   	struct drm_sched_rq		sched_rq[DRM_SCHED_PRIORITY_MAX];
> +	struct drm_sched_job            *curr_job;
>   	wait_queue_head_t		wake_up_worker;
>   	wait_queue_head_t		job_scheduled;
>   	atomic_t			hw_rq_count;