On 2023-10-26 00:12, Matthew Brost wrote:
> Rather than call free_job and run_job in same work item have a dedicated
> work item for each. This aligns with the design and intended use of work
> queues.
>
> v2:
> - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
> timestamp in free_job() work item (Danilo)
> v3:
> - Drop forward dec of drm_sched_select_entity (Boris)
> - Return in drm_sched_run_job_work if entity NULL (Boris)
> v4:
> - Replace dequeue with peek and invert logic (Luben)
> - Wrap to 100 lines (Luben)
> - Update comments for *_queue / *_queue_if_ready functions (Luben)
> v5:
> - Drop peek argument, blindly blindly reinit idle (Luben)
> - s/drm_sched_free_job_queue_if_ready/drm_sched_free_job_queue_if_done
> (Luben)
> - Update work_run_job & work_free_job kernel doc (Luben)
>
> Signed-off-by: Matthew Brost <matthew.br...@intel.com>
> ---
> drivers/gpu/drm/scheduler/sched_main.c | 241 +++++++++++++++----------
> include/drm/gpu_scheduler.h | 8 +-
> 2 files changed, 151 insertions(+), 98 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c
> b/drivers/gpu/drm/scheduler/sched_main.c
> index b22157e920d4..3d89420d4ffb 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -257,12 +257,89 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
>
> /**
> * drm_sched_run_job_queue - enqueue scheduler submission
> + * drm_sched_run_job_queue - enqueue run-job work
> * @sched: scheduler instance
> */
> static void drm_sched_run_job_queue(struct drm_gpu_scheduler *sched)
> {
> if (!READ_ONCE(sched->pause_submit))
> - queue_work(sched->submit_wq, &sched->work_submit);
> + queue_work(sched->submit_wq, &sched->work_run_job);
> +}
> +
> +/**
> + * drm_sched_can_queue -- Can we queue more to the hardware?
> + * @sched: scheduler instance
> + *
> + * Return true if we can push more jobs to the hw, otherwise false.
> + */
> +static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
> +{
> + return atomic_read(&sched->hw_rq_count) <
> + sched->hw_submission_limit;
> +}
> +
> +/**
> + * drm_sched_select_entity - Select next entity to process
> + *
> + * @sched: scheduler instance
> + *
> + * Returns the entity to process or NULL if none are found.
> + */
> +static struct drm_sched_entity *
> +drm_sched_select_entity(struct drm_gpu_scheduler *sched)
> +{
> + struct drm_sched_entity *entity;
> + int i;
> +
> + if (!drm_sched_can_queue(sched))
> + return NULL;
> +
> + /* Kernel run queue has higher priority than normal run queue*/
> + for (i = sched->num_rqs - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> + entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> + drm_sched_rq_select_entity_fifo(sched->sched_rq[i]) :
> + drm_sched_rq_select_entity_rr(sched->sched_rq[i]);
> + if (entity)
> + break;
> + }
> +
> + return entity;
> +}
> +
Could you please rewrite the patch so as to not do the unnecessary move
of the drm_sched_select_entity(). This function has no changes in it,
and this move a few lines up only creates noise, when doing "git blame"
and similar data-mining.
So, just rewrite the patch without moving unchanged code up/down, so
that only the essential differences are shown by git-diff(1). This makes
it easy to review, easy to do data-mining down the road, and so on.
The rest of the patch looks good.
Thanks!
Regards,
Luben
> +/**
> + * drm_sched_run_job_queue_if_ready - enqueue run-job work if ready
> + * @sched: scheduler instance
> + */
> +static void drm_sched_run_job_queue_if_ready(struct drm_gpu_scheduler *sched)
> +{
> + if (drm_sched_select_entity(sched))
> + drm_sched_run_job_queue(sched);
> +}
> +
> +/**
> + * drm_sched_free_job_queue - enqueue free-job work
> + * @sched: scheduler instance
> + */
> +static void drm_sched_free_job_queue(struct drm_gpu_scheduler *sched)
> +{
> + if (!READ_ONCE(sched->pause_submit))
> + queue_work(sched->submit_wq, &sched->work_free_job);
> +}
> +
> +/**
> + * drm_sched_free_job_queue_if_done - enqueue free-job work if ready
> + * @sched: scheduler instance
> + */
> +static void drm_sched_free_job_queue_if_done(struct drm_gpu_scheduler *sched)
> +{
> + struct drm_sched_job *job;
> +
> + spin_lock(&sched->job_list_lock);
> + job = list_first_entry_or_null(&sched->pending_list,
> + struct drm_sched_job, list);
> + if (job && dma_fence_is_signaled(&job->s_fence->finished))
> + drm_sched_free_job_queue(sched);
> + spin_unlock(&sched->job_list_lock);
> }
>
> /**
> @@ -284,7 +361,7 @@ static void drm_sched_job_done(struct drm_sched_job
> *s_job, int result)
> dma_fence_get(&s_fence->finished);
> drm_sched_fence_finished(s_fence, result);
> dma_fence_put(&s_fence->finished);
> - drm_sched_run_job_queue(sched);
> + drm_sched_free_job_queue(sched);
> }
>
> /**
> @@ -550,7 +627,7 @@ void drm_sched_start(struct drm_gpu_scheduler *sched,
> bool full_recovery)
> drm_sched_job_done(s_job, fence->error);
> else if (r)
> DRM_DEV_ERROR(sched->dev, "fence add callback
> failed (%d)\n",
> - r);
> + r);
> } else
> drm_sched_job_done(s_job, -ECANCELED);
> }
> @@ -862,18 +939,6 @@ void drm_sched_job_cleanup(struct drm_sched_job *job)
> }
> EXPORT_SYMBOL(drm_sched_job_cleanup);
>
> -/**
> - * drm_sched_can_queue -- Can we queue more to the hardware?
> - * @sched: scheduler instance
> - *
> - * Return true if we can push more jobs to the hw, otherwise false.
> - */
> -static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
> -{
> - return atomic_read(&sched->hw_rq_count) <
> - sched->hw_submission_limit;
> -}
> -
> /**
> * drm_sched_wakeup_if_can_queue - Wake up the scheduler
> * @sched: scheduler instance
> @@ -886,34 +951,6 @@ void drm_sched_wakeup_if_can_queue(struct
> drm_gpu_scheduler *sched)
> drm_sched_run_job_queue(sched);
> }
>
> -/**
> - * drm_sched_select_entity - Select next entity to process
> - *
> - * @sched: scheduler instance
> - *
> - * Returns the entity to process or NULL if none are found.
> - */
> -static struct drm_sched_entity *
> -drm_sched_select_entity(struct drm_gpu_scheduler *sched)
> -{
> - struct drm_sched_entity *entity;
> - int i;
> -
> - if (!drm_sched_can_queue(sched))
> - return NULL;
> -
> - /* Kernel run queue has higher priority than normal run queue*/
> - for (i = sched->num_rqs - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> - entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> - drm_sched_rq_select_entity_fifo(sched->sched_rq[i]) :
> - drm_sched_rq_select_entity_rr(sched->sched_rq[i]);
> - if (entity)
> - break;
> - }
> -
> - return entity;
> -}
> -
> /**
> * drm_sched_get_cleanup_job - fetch the next finished job to be destroyed
> *
> @@ -943,8 +980,10 @@ drm_sched_get_cleanup_job(struct drm_gpu_scheduler
> *sched)
> typeof(*next), list);
>
> if (next) {
> - next->s_fence->scheduled.timestamp =
> - dma_fence_timestamp(&job->s_fence->finished);
> + if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT,
> + &next->s_fence->scheduled.flags))
> + next->s_fence->scheduled.timestamp =
> +
> dma_fence_timestamp(&job->s_fence->finished);
> /* start TO timer for next job */
> drm_sched_start_timeout(sched);
> }
> @@ -994,74 +1033,83 @@ drm_sched_pick_best(struct drm_gpu_scheduler
> **sched_list,
> EXPORT_SYMBOL(drm_sched_pick_best);
>
> /**
> - * drm_sched_main - main scheduler thread
> + * drm_sched_free_job_work - worker to call free_job
> *
> - * @param: scheduler instance
> + * @w: free job work
> */
> -static void drm_sched_main(struct work_struct *w)
> +static void drm_sched_free_job_work(struct work_struct *w)
> {
> struct drm_gpu_scheduler *sched =
> - container_of(w, struct drm_gpu_scheduler, work_submit);
> - struct drm_sched_entity *entity;
> + container_of(w, struct drm_gpu_scheduler, work_free_job);
> struct drm_sched_job *cleanup_job;
> - int r;
>
> if (READ_ONCE(sched->pause_submit))
> return;
>
> cleanup_job = drm_sched_get_cleanup_job(sched);
> - entity = drm_sched_select_entity(sched);
> -
> - if (!entity && !cleanup_job)
> - return; /* No more work */
> -
> - if (cleanup_job)
> + if (cleanup_job) {
> sched->ops->free_job(cleanup_job);
>
> - if (entity) {
> - struct dma_fence *fence;
> - struct drm_sched_fence *s_fence;
> - struct drm_sched_job *sched_job;
> -
> - sched_job = drm_sched_entity_pop_job(entity);
> - if (!sched_job) {
> - complete_all(&entity->entity_idle);
> - if (!cleanup_job)
> - return; /* No more work */
> - goto again;
> - }
> + drm_sched_free_job_queue_if_done(sched);
> + drm_sched_run_job_queue_if_ready(sched);
> + }
> +}
>
> - s_fence = sched_job->s_fence;
> +/**
> + * drm_sched_run_job_work - worker to call run_job
> + *
> + * @w: run job work
> + */
> +static void drm_sched_run_job_work(struct work_struct *w)
> +{
> + struct drm_gpu_scheduler *sched =
> + container_of(w, struct drm_gpu_scheduler, work_run_job);
> + struct drm_sched_entity *entity;
> + struct dma_fence *fence;
> + struct drm_sched_fence *s_fence;
> + struct drm_sched_job *sched_job;
> + int r;
>
> - atomic_inc(&sched->hw_rq_count);
> - drm_sched_job_begin(sched_job);
> + if (READ_ONCE(sched->pause_submit))
> + return;
>
> - trace_drm_run_job(sched_job, entity);
> - fence = sched->ops->run_job(sched_job);
> + entity = drm_sched_select_entity(sched);
> + if (!entity)
> + return;
> +
> + sched_job = drm_sched_entity_pop_job(entity);
> + if (!sched_job) {
> complete_all(&entity->entity_idle);
> - drm_sched_fence_scheduled(s_fence, fence);
> + return; /* No more work */
> + }
>
> - if (!IS_ERR_OR_NULL(fence)) {
> - /* Drop for original kref_init of the fence */
> - dma_fence_put(fence);
> + s_fence = sched_job->s_fence;
>
> - r = dma_fence_add_callback(fence, &sched_job->cb,
> - drm_sched_job_done_cb);
> - if (r == -ENOENT)
> - drm_sched_job_done(sched_job, fence->error);
> - else if (r)
> - DRM_DEV_ERROR(sched->dev, "fence add callback
> failed (%d)\n",
> - r);
> - } else {
> - drm_sched_job_done(sched_job, IS_ERR(fence) ?
> - PTR_ERR(fence) : 0);
> - }
> + atomic_inc(&sched->hw_rq_count);
> + drm_sched_job_begin(sched_job);
>
> - wake_up(&sched->job_scheduled);
> + trace_drm_run_job(sched_job, entity);
> + fence = sched->ops->run_job(sched_job);
> + complete_all(&entity->entity_idle);
> + drm_sched_fence_scheduled(s_fence, fence);
> +
> + if (!IS_ERR_OR_NULL(fence)) {
> + /* Drop for original kref_init of the fence */
> + dma_fence_put(fence);
> +
> + r = dma_fence_add_callback(fence, &sched_job->cb,
> + drm_sched_job_done_cb);
> + if (r == -ENOENT)
> + drm_sched_job_done(sched_job, fence->error);
> + else if (r)
> + DRM_DEV_ERROR(sched->dev, "fence add callback failed
> (%d)\n", r);
> + } else {
> + drm_sched_job_done(sched_job, IS_ERR(fence) ?
> + PTR_ERR(fence) : 0);
> }
>
> -again:
> - drm_sched_run_job_queue(sched);
> + wake_up(&sched->job_scheduled);
> + drm_sched_run_job_queue_if_ready(sched);
> }
>
> /**
> @@ -1146,7 +1194,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> spin_lock_init(&sched->job_list_lock);
> atomic_set(&sched->hw_rq_count, 0);
> INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout);
> - INIT_WORK(&sched->work_submit, drm_sched_main);
> + INIT_WORK(&sched->work_run_job, drm_sched_run_job_work);
> + INIT_WORK(&sched->work_free_job, drm_sched_free_job_work);
> atomic_set(&sched->_score, 0);
> atomic64_set(&sched->job_id_count, 0);
> sched->pause_submit = false;
> @@ -1273,7 +1322,8 @@ EXPORT_SYMBOL(drm_sched_wqueue_ready);
> void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
> {
> WRITE_ONCE(sched->pause_submit, true);
> - cancel_work_sync(&sched->work_submit);
> + cancel_work_sync(&sched->work_run_job);
> + cancel_work_sync(&sched->work_free_job);
> }
> EXPORT_SYMBOL(drm_sched_wqueue_stop);
>
> @@ -1285,6 +1335,7 @@ EXPORT_SYMBOL(drm_sched_wqueue_stop);
> void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
> {
> WRITE_ONCE(sched->pause_submit, false);
> - queue_work(sched->submit_wq, &sched->work_submit);
> + queue_work(sched->submit_wq, &sched->work_run_job);
> + queue_work(sched->submit_wq, &sched->work_free_job);
> }
> EXPORT_SYMBOL(drm_sched_wqueue_start);
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 1d52b8bbb06c..37749f561866 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -480,9 +480,10 @@ struct drm_sched_backend_ops {
> * finished.
> * @hw_rq_count: the number of jobs currently in the hardware queue.
> * @job_id_count: used to assign unique id to the each job.
> - * @submit_wq: workqueue used to queue @work_submit
> + * @submit_wq: workqueue used to queue @work_run_job and @work_free_job
> * @timeout_wq: workqueue used to queue @work_tdr
> - * @work_submit: schedules jobs and cleans up entities
> + * @work_run_job: work which calls run_job op of each scheduler.
> + * @work_free_job: work which calls free_job op of each scheduler.
> * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
> * timeout interval is over.
> * @pending_list: the list of jobs which are currently in the job queue.
> @@ -511,7 +512,8 @@ struct drm_gpu_scheduler {
> atomic64_t job_id_count;
> struct workqueue_struct *submit_wq;
> struct workqueue_struct *timeout_wq;
> - struct work_struct work_submit;
> + struct work_struct work_run_job;
> + struct work_struct work_free_job;
> struct delayed_work work_tdr;
> struct list_head pending_list;
> spinlock_t job_list_lock;
