Re: [PATCH 1/4] drm/sched: Add job popping API

["Christian König" <christian.koenig@amd.com>]

Am 20.01.25 um 18:13 schrieb Danilo Krummrich:
> On Mon, Jan 20, 2025 at 04:52:37PM +0000, Tvrtko Ursulin wrote:
>> Idea is to add a helper for popping jobs from the entity with the goal
>> of making amdgpu use it in the next patch. That way amdgpu will decouple
>> itself a tiny bit more from scheduler implementation details.
> I object to adding this function if it's *only* used for something that looks
> like an abuse of the API by amdgpu. Let's not make that more convenient.

Completely agree. Since when do we have that?

I don't remember agreeing to anything which messes so badly with 
scheduler internals.

Regards,
Christian.

>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
>> Cc: Christian König <christian.koenig@amd.com>
>> Cc: Danilo Krummrich <dakr@kernel.org>
>> Cc: Matthew Brost <matthew.brost@intel.com>
>> Cc: Philipp Stanner <phasta@kernel.org>
>> ---
>>   drivers/gpu/drm/scheduler/sched_entity.c |  2 +-
>>   include/drm/gpu_scheduler.h              | 21 +++++++++++++++++++++
>>   2 files changed, 22 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
>> index 69bcf0e99d57..7c0d266a89ef 100644
>> --- a/drivers/gpu/drm/scheduler/sched_entity.c
>> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
>> @@ -255,7 +255,7 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
>>   	/* The entity is guaranteed to not be used by the scheduler */
>>   	prev = rcu_dereference_check(entity->last_scheduled, true);
>>   	dma_fence_get(prev);
>> -	while ((job = to_drm_sched_job(spsc_queue_pop(&entity->job_queue)))) {
>> +	while ((job = __drm_sched_entity_pop_job(entity))) {
>>   		struct drm_sched_fence *s_fence = job->s_fence;
>>   
>>   		dma_fence_get(&s_fence->finished);
>> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
>> index a0ff08123f07..092242f2464f 100644
>> --- a/include/drm/gpu_scheduler.h
>> +++ b/include/drm/gpu_scheduler.h
>> @@ -611,6 +611,27 @@ void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
>>   bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);
>>   int drm_sched_entity_error(struct drm_sched_entity *entity);
>>   
>> +/**
>> + * __drm_sched_entity_pop_job - Low level helper for popping queued jobs
>> + *
>> + * @entity: scheduler entity
>> + *
>> + * Low level helper for popping queued jobs. Drivers should not use it.
>> + *
>> + * Returns the job dequeued or NULL.
>> + */
>> +static inline struct drm_sched_job *
>> +__drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>> +{
>> +	struct spsc_node *node;
>> +
>> +	node = spsc_queue_pop(&entity->job_queue);
>> +	if (!node)
>> +		return NULL;
>> +
>> +	return container_of(node, struct drm_sched_job, queue_node);
>> +}
>> +
>>   struct drm_sched_fence *drm_sched_fence_alloc(
>>   	struct drm_sched_entity *s_entity, void *owner);
>>   void drm_sched_fence_init(struct drm_sched_fence *fence,
>> -- 
>> 2.47.1
>>