[PATCH 1/3] drm/sched: Add callback to mark if sched is ready to work.

[Koenig, Christian]

Am 18.10.18 um 20:44 schrieb Andrey Grodzovsky:
> Problem:
> A particular scheduler may become unsuable (underlying HW) after
> some event (e.g. GPU reset). If it's later chosen by
> the get free sched. policy a command will fail to be
> submitted.
>
> Fix:
> Add a driver specific callback to report the sced. status so
> rq with bad sched. can be avoided in favor of working one or
> none in which case job init will fail.

I would rather go with the approach of moving the ready flag completely 
into the scheduler instead.

Christian.

>
> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c |  9 ++++++++-
>   drivers/gpu/drm/etnaviv/etnaviv_sched.c   |  3 ++-
>   drivers/gpu/drm/scheduler/sched_entity.c  | 11 ++++++++++-
>   drivers/gpu/drm/scheduler/sched_main.c    |  8 +++++++-
>   drivers/gpu/drm/v3d/v3d_sched.c           |  3 ++-
>   include/drm/gpu_scheduler.h               |  5 ++++-
>   6 files changed, 33 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
> index 5448cf2..bbfe7f501 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
> @@ -404,6 +404,13 @@ int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,
>   	return 0;
>   }
>   
> +static bool amdgpu_ring_ready(struct drm_gpu_scheduler *sched)
> +{
> +	struct amdgpu_ring *ring = to_amdgpu_ring(sched);
> +
> +	return ring->ready;
> +}
> +
>   /**
>    * amdgpu_fence_driver_init_ring - init the fence driver
>    * for the requested ring.
> @@ -450,7 +457,7 @@ int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring,
>   
>   		r = drm_sched_init(&ring->sched, &amdgpu_sched_ops,
>   				   num_hw_submission, amdgpu_job_hang_limit,
> -				   timeout, ring->name);
> +				   timeout, ring->name, amdgpu_ring_ready);
>   		if (r) {
>   			DRM_ERROR("Failed to create scheduler on ring %s.\n",
>   				  ring->name);
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> index f8c5f1e..5094013 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> @@ -178,7 +178,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
>   
>   	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops,
>   			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
> -			     msecs_to_jiffies(500), dev_name(gpu->dev));
> +			     msecs_to_jiffies(500), dev_name(gpu->dev),
> +				 NULL);
>   	if (ret)
>   		return ret;
>   
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index 3e22a54..320c77a 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -130,7 +130,16 @@ drm_sched_entity_get_free_sched(struct drm_sched_entity *entity)
>   	int i;
>   
>   	for (i = 0; i < entity->num_rq_list; ++i) {
> -		num_jobs = atomic_read(&entity->rq_list[i]->sched->num_jobs);
> +		struct drm_gpu_scheduler *sched = entity->rq_list[i]->sched;
> +
> +		if (entity->rq_list[i]->sched->ready &&
> +				!entity->rq_list[i]->sched->ready(sched)) {
> +			DRM_WARN("sched%s is not ready, skipping", sched->name);
> +
> +			continue;
> +		}
> +
> +		num_jobs = atomic_read(&sched->num_jobs);
>   		if (num_jobs < min_jobs) {
>   			min_jobs = num_jobs;
>   			rq = entity->rq_list[i];
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 63b997d..6b151f2 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -420,6 +420,9 @@ int drm_sched_job_init(struct drm_sched_job *job,
>   	struct drm_gpu_scheduler *sched;
>   
>   	drm_sched_entity_select_rq(entity);
> +	if (!entity->rq)
> +		return -ENOENT;
> +
>   	sched = entity->rq->sched;
>   
>   	job->sched = sched;
> @@ -606,7 +609,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>   		   unsigned hw_submission,
>   		   unsigned hang_limit,
>   		   long timeout,
> -		   const char *name)
> +		   const char *name,
> +		   bool (*ready)(struct drm_gpu_scheduler *sched))
>   {
>   	int i;
>   	sched->ops = ops;
> @@ -633,6 +637,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>   		return PTR_ERR(sched->thread);
>   	}
>   
> +	sched->ready = ready;
> +
>   	return 0;
>   }
>   EXPORT_SYMBOL(drm_sched_init);
> diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> index 80b641f..e06cc0d 100644
> --- a/drivers/gpu/drm/v3d/v3d_sched.c
> +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> @@ -212,7 +212,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>   			     &v3d_sched_ops,
>   			     hw_jobs_limit, job_hang_limit,
>   			     msecs_to_jiffies(hang_limit_ms),
> -			     "v3d_bin");
> +			     "v3d_bin",
> +				 NULL);
>   	if (ret) {
>   		dev_err(v3d->dev, "Failed to create bin scheduler: %d.", ret);
>   		return ret;
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 0684dcd..a6e18fe 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -283,12 +283,15 @@ struct drm_gpu_scheduler {
>   	spinlock_t			job_list_lock;
>   	int				hang_limit;
>   	atomic_t                        num_jobs;
> +
> +	bool 			(*ready)(struct drm_gpu_scheduler *sched);
>   };
>   
>   int drm_sched_init(struct drm_gpu_scheduler *sched,
>   		   const struct drm_sched_backend_ops *ops,
>   		   uint32_t hw_submission, unsigned hang_limit, long timeout,
> -		   const char *name);
> +		   const char *name,
> +		   bool (*ready)(struct drm_gpu_scheduler *sched));
>   void drm_sched_fini(struct drm_gpu_scheduler *sched);
>   int drm_sched_job_init(struct drm_sched_job *job,
>   		       struct drm_sched_entity *entity,