5.0-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 1decbf6bb0b4dc56c9da6c5e57b994ebfc2be3aa ]
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@basnieuwenhuizen.nl Reviewed-by: Christian König christian.koenig@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 e2942c9a11a7..35ddbec1375a 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); }