[PATCH] drm/sched: Only start TDR in drm_sched_job_begin on first job

[Christian König]

Am 25.07.24 um 01:44 schrieb Matthew Brost:
> Only start in drm_sched_job_begin on first job being added to the
> pending list as if pending list non-empty the TDR has already been
> started. It is problematic to restart the TDR as it will extend TDR
> period for an already running job, potentially leading to dma-fence
> signaling for a very long period of with continous stream of jobs.

Mhm, that should be unnecessary. drm_sched_start_timeout() should only 
start the timeout, but never re-start it.

Could be that this isn't working properly.

Regards,
Christian.

>
> Cc: Christian König <christian.koenig at amd.com>
> Signed-off-by: Matthew Brost <matthew.brost at intel.com>
> ---
>   drivers/gpu/drm/scheduler/sched_main.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 7e90c9f95611..feeeb9dbeb86 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -540,7 +540,8 @@ static void drm_sched_job_begin(struct drm_sched_job *s_job)
>   
>   	spin_lock(&sched->job_list_lock);
>   	list_add_tail(&s_job->list, &sched->pending_list);
> -	drm_sched_start_timeout(sched);
> +	if (list_is_singular(&sched->pending_list))
> +		drm_sched_start_timeout(sched);
>   	spin_unlock(&sched->job_list_lock);
>   }
>