Am 30.01.19 um 02:53 schrieb Bas Nieuwenhuizen:
> Some blocks in amdgpu can have 0 rqs.
>
> Job creation already fails with -ENOENT when entity->rq is NULL,
> so jobs cannot be pushed. Without a rq there is no scheduler to
> pop jobs, and rq selection already does the right thing with a
> list of length 0.
>
> So the operations we need to fix are:
> - Creation, do not set rq to rq_list[0] if the list can have length 0.
> - Do not flush any jobs when there is no rq.
> - On entity destruction handle the rq = NULL case.
> - on set_priority, do not try to change the rq if it is NULL.
>
> Signed-off-by: Bas Nieuwenhuizen <bas at basnieuwenhuizen.nl>
One minor comment on patch #2, apart from that the series is
Reviewed-by: Christian König <christian.koenig at amd.com>.
I'm going to make the change on #2 and pick them up for inclusion in
amd-staging-drm-next.
Thanks for the help,
Christian.
> ---
> drivers/gpu/drm/scheduler/sched_entity.c | 39 ++++++++++++++++--------
> 1 file changed, 26 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index 4463d3826ecb..8e31b6628d09 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -52,12 +52,12 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
> {
> int i;
>
> - if (!(entity && rq_list && num_rq_list > 0 && rq_list[0]))
> + if (!(entity && rq_list && (num_rq_list == 0 || rq_list[0])))
> return -EINVAL;
>
> memset(entity, 0, sizeof(struct drm_sched_entity));
> INIT_LIST_HEAD(&entity->list);
> - entity->rq = rq_list[0];
> + entity->rq = NULL;
> entity->guilty = guilty;
> entity->num_rq_list = num_rq_list;
> entity->rq_list = kcalloc(num_rq_list, sizeof(struct drm_sched_rq *),
> @@ -67,6 +67,10 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>
> for (i = 0; i < num_rq_list; ++i)
> entity->rq_list[i] = rq_list[i];
> +
> + if (num_rq_list)
> + entity->rq = rq_list[0];
> +
> entity->last_scheduled = NULL;
>
> spin_lock_init(&entity->rq_lock);
> @@ -165,6 +169,9 @@ long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
> struct task_struct *last_user;
> long ret = timeout;
>
> + if (!entity->rq)
> + return 0;
> +
> sched = entity->rq->sched;
> /**
> * The client will not queue more IBs during this fini, consume existing
> @@ -264,20 +271,24 @@ static void drm_sched_entity_kill_jobs(struct drm_sched_entity *entity)
> */
> void drm_sched_entity_fini(struct drm_sched_entity *entity)
> {
> - struct drm_gpu_scheduler *sched;
> + struct drm_gpu_scheduler *sched = NULL;
>
> - sched = entity->rq->sched;
> - drm_sched_rq_remove_entity(entity->rq, entity);
> + if (entity->rq) {
> + sched = entity->rq->sched;
> + drm_sched_rq_remove_entity(entity->rq, entity);
> + }
>
> /* Consumption of existing IBs wasn't completed. Forcefully
> * remove them here.
> */
> if (spsc_queue_peek(&entity->job_queue)) {
> - /* Park the kernel for a moment to make sure it isn't processing
> - * our enity.
> - */
> - kthread_park(sched->thread);
> - kthread_unpark(sched->thread);
> + if (sched) {
> + /* Park the kernel for a moment to make sure it isn't processing
> + * our enity.
> + */
> + kthread_park(sched->thread);
> + kthread_unpark(sched->thread);
> + }
> if (entity->dependency) {
> dma_fence_remove_callback(entity->dependency,
> &entity->cb);
> @@ -362,9 +373,11 @@ void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
> for (i = 0; i < entity->num_rq_list; ++i)
> drm_sched_entity_set_rq_priority(&entity->rq_list[i], priority);
>
> - drm_sched_rq_remove_entity(entity->rq, entity);
> - drm_sched_entity_set_rq_priority(&entity->rq, priority);
> - drm_sched_rq_add_entity(entity->rq, entity);
> + if (entity->rq) {
> + drm_sched_rq_remove_entity(entity->rq, entity);
> + drm_sched_entity_set_rq_priority(&entity->rq, priority);
> + drm_sched_rq_add_entity(entity->rq, entity);
> + }
>
> spin_unlock(&entity->rq_lock);
> }