@@ -538,10 +538,10 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
return;
/*
- * Only when the queue is empty are we guaranteed that the scheduler
- * thread cannot change ->last_scheduled. To enforce ordering we need
- * a read barrier here. See drm_sched_entity_pop_job() for the other
- * side.
+ * Only when the queue is empty are we guaranteed that
+ * drm_sched_run_job_work() cannot change entity->last_scheduled. To
+ * enforce ordering we need a read barrier here. See
+ * drm_sched_entity_pop_job() for the other side.
*/
smp_rmb();
@@ -389,7 +389,7 @@ static void drm_sched_run_free_queue(struct drm_gpu_scheduler *sched)
* drm_sched_job_done - complete a job
* @s_job: pointer to the job which is done
*
- * Finish the job's fence and wake up the worker thread.
+ * Finish the job's fence and resubmit the work items.
*/
static void drm_sched_job_done(struct drm_sched_job *s_job, int result)
{
@@ -549,9 +549,10 @@ static void drm_sched_job_timedout(struct work_struct *work)
if (job) {
/*
- * Remove the bad job so it cannot be freed by concurrent
- * drm_sched_cleanup_jobs. It will be reinserted back after sched->thread
- * is parked at which point it's safe.
+ * Remove the bad job so it cannot be freed by a concurrent
+ * &struct drm_sched_backend_ops.free_job. It will be
+ * reinserted after the scheduler's work items have been
+ * cancelled, at which point it's safe.
*/
list_del_init(&job->list);
spin_unlock(&sched->job_list_lock);
@@ -597,10 +598,10 @@ void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad)
/*
* Reinsert back the bad job here - now it's safe as
- * drm_sched_get_finished_job cannot race against us and release the
+ * drm_sched_get_finished_job() cannot race against us and release the
* bad job at this point - we parked (waited for) any in progress
- * (earlier) cleanups and drm_sched_get_finished_job will not be called
- * now until the scheduler thread is unparked.
+ * (earlier) cleanups and drm_sched_get_finished_job() will not be
+ * called now until the scheduler's work items are submitted again.
*/
if (bad && bad->sched == sched)
/*
@@ -613,7 +614,8 @@ void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad)
* Iterate the job list from later to earlier one and either deactive
* their HW callbacks or remove them from pending list if they already
* signaled.
- * This iteration is thread safe as sched thread is stopped.
+ * This iteration is thread safe as the scheduler's work items have been
+ * cancelled.
*/
list_for_each_entry_safe_reverse(s_job, tmp, &sched->pending_list,
list) {
@@ -678,9 +680,9 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, int errno)
struct drm_sched_job *s_job, *tmp;
/*
- * Locking the list is not required here as the sched thread is parked
- * so no new jobs are being inserted or removed. Also concurrent
- * GPU recovers can't run in parallel.
+ * Locking the list is not required here as the scheduler's work items
+ * are currently not running, so no new jobs are being inserted or
+ * removed. Also concurrent GPU recovers can't run in parallel.
*/
list_for_each_entry_safe(s_job, tmp, &sched->pending_list, list) {
struct dma_fence *fence = s_job->s_fence->parent;
@@ -192,7 +192,7 @@ struct drm_sched_entity {
* @last_scheduled:
*
* Points to the finished fence of the last scheduled job. Only written
- * by the scheduler thread, can be accessed locklessly from
+ * by drm_sched_entity_pop_job(). Can be accessed locklessly from
* drm_sched_job_arm() if the queue is empty.
*/
struct dma_fence __rcu *last_scheduled;
@@ -426,14 +426,14 @@ struct drm_sched_backend_ops {
* Drivers typically issue a reset to recover from GPU hangs, and this
* procedure usually follows the following workflow:
*
- * 1. Stop the scheduler using drm_sched_stop(). This will park the
- * scheduler thread and cancel the timeout work, guaranteeing that
- * nothing is queued while we reset the hardware queue
+ * 1. Stop the scheduler using drm_sched_stop(). This will cancel the
+ * scheduler's work items, guaranteeing that nothing is queued while
+ * we reset the hardware queue.
* 2. Try to gracefully stop non-faulty jobs (optional)
* 3. Issue a GPU reset (driver-specific)
* 4. Re-submit jobs using drm_sched_resubmit_jobs()
* 5. Restart the scheduler using drm_sched_start(). At that point, new
- * jobs can be queued, and the scheduler thread is unblocked
+ * jobs can be queued, and the scheduler's work items are resubmitted.
*
* Note that some GPUs have distinct hardware queues but need to reset
* the GPU globally, which requires extra synchronization between the
The GPU scheduler's comments refer to a "thread" at various places. Those are leftovers from commit a6149f039369 ("drm/sched: Convert drm scheduler to use a work queue rather than kthread"). Replace all references to kthreads. Signed-off-by: Philipp Stanner <phasta@kernel.org> --- Changes in v2: - Speak consistently about work items. (Danilo) - Remove Fixes: tags. (Danilo) --- drivers/gpu/drm/scheduler/sched_entity.c | 8 ++++---- drivers/gpu/drm/scheduler/sched_main.c | 24 +++++++++++++----------- include/drm/gpu_scheduler.h | 10 +++++----- 3 files changed, 22 insertions(+), 20 deletions(-)