[RFC PATCH 07/10] drm/sched: Add helper to set TDR timeout

[Luben Tuikov]

On 2023-04-03 20:22, Matthew Brost wrote:
> Add helper to set TDR timeout and restart the TDR with new timeout
> value. This will be used in XE, new Intel GPU driver, to trigger the TDR
> to cleanup drm_sched_entity that encounter errors.
> 
> Signed-off-by: Matthew Brost <matthew.brost at intel.com>
> ---
>  drivers/gpu/drm/scheduler/sched_main.c | 18 ++++++++++++++++++
>  include/drm/gpu_scheduler.h            |  1 +
>  2 files changed, 19 insertions(+)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 4eac02d212c1..d61880315d8d 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -370,6 +370,24 @@ static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
>  		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
>  }
>  
> +/**
> + * drm_sched_set_timeout - set timeout for reset worker
> + *
> + * @sched: scheduler instance to set and (re)-start the worker for
> + * @timeout: timeout period
> + *
> + * Set and (re)-start the timeout for the given scheduler.
> + */
> +void drm_sched_set_timeout(struct drm_gpu_scheduler *sched, long timeout)
> +{
> +	spin_lock(&sched->job_list_lock);
> +	sched->timeout = timeout;
> +	cancel_delayed_work(&sched->work_tdr);

I see that the comment says "(re-)start"(sic). Is the rest of the logic
stable in that we don't need to use _sync() version, and/or at least
inspect the return value of the one currently used?

Regards,
Luben

> +	drm_sched_start_timeout(sched);
> +	spin_unlock(&sched->job_list_lock);
> +}
> +EXPORT_SYMBOL(drm_sched_set_timeout);
> +
>  /**
>   * drm_sched_fault - immediately start timeout handler
>   *
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 18172ae63ab7..6258e324bd7c 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -593,6 +593,7 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
>  				    struct drm_gpu_scheduler **sched_list,
>                                     unsigned int num_sched_list);
>  
> +void drm_sched_set_timeout(struct drm_gpu_scheduler *sched, long timeout);
>  void drm_sched_job_cleanup(struct drm_sched_job *job);
>  void drm_sched_wakeup(struct drm_gpu_scheduler *sched);
>  void drm_sched_add_msg(struct drm_gpu_scheduler *sched,