drm_sched_cleanup_jobs() attempts to free finished jobs, however because it is called as the condition of wait_event_interruptible() it must not sleep. Unfortuantly some free callbacks (notibly for Panfrost) do sleep.
Instead let's rename drm_sched_cleanup_jobs() to drm_sched_get_cleanup_job() and simply return a job for processing if there is one. The caller can then call the free_job() callback outside the wait_event_interruptible() where sleeping is possible before re-checking and returning to sleep if necessary.
Signed-off-by: Steven Price steven.price@arm.com ---
Changes from v1: * Move list_first_entry_or_null() within the lock
drivers/gpu/drm/scheduler/sched_main.c | 44 ++++++++++++++------------ 1 file changed, 24 insertions(+), 20 deletions(-)
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 9a0ee74d82dc..0ed4aaa4e6d1 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -622,43 +622,41 @@ static void drm_sched_process_job(struct dma_fence *f, struct dma_fence_cb *cb) }
/** - * drm_sched_cleanup_jobs - destroy finished jobs + * drm_sched_get_cleanup_job - fetch the next finished job to be destroyed * * @sched: scheduler instance * - * Remove all finished jobs from the mirror list and destroy them. + * Returns the next finished job from the mirror list (if there is one) + * ready for it to be destroyed. */ -static void drm_sched_cleanup_jobs(struct drm_gpu_scheduler *sched) +static struct drm_sched_job * +drm_sched_get_cleanup_job(struct drm_gpu_scheduler *sched) { + struct drm_sched_job *job = NULL; unsigned long flags;
/* Don't destroy jobs while the timeout worker is running */ if (sched->timeout != MAX_SCHEDULE_TIMEOUT && !cancel_delayed_work(&sched->work_tdr)) - return; - - - while (!list_empty(&sched->ring_mirror_list)) { - struct drm_sched_job *job; + return NULL;
- job = list_first_entry(&sched->ring_mirror_list, + job = list_first_entry_or_null(&sched->ring_mirror_list, struct drm_sched_job, node); - if (!dma_fence_is_signaled(&job->s_fence->finished)) - break;
- spin_lock_irqsave(&sched->job_list_lock, flags); + spin_lock_irqsave(&sched->job_list_lock, flags); + + if (job && dma_fence_is_signaled(&job->s_fence->finished)) { /* remove job from ring_mirror_list */ list_del_init(&job->node); - spin_unlock_irqrestore(&sched->job_list_lock, flags); - - sched->ops->free_job(job); + } else { + job = NULL; + /* queue timeout for next job */ + drm_sched_start_timeout(sched); }
- /* queue timeout for next job */ - spin_lock_irqsave(&sched->job_list_lock, flags); - drm_sched_start_timeout(sched); spin_unlock_irqrestore(&sched->job_list_lock, flags);
+ return job; }
/** @@ -698,12 +696,18 @@ static int drm_sched_main(void *param) struct drm_sched_fence *s_fence; struct drm_sched_job *sched_job; struct dma_fence *fence; + struct drm_sched_job *cleanup_job = NULL;
wait_event_interruptible(sched->wake_up_worker, - (drm_sched_cleanup_jobs(sched), + (cleanup_job = drm_sched_get_cleanup_job(sched)) || (!drm_sched_blocked(sched) && (entity = drm_sched_select_entity(sched))) || - kthread_should_stop())); + kthread_should_stop()); + + while (cleanup_job) { + sched->ops->free_job(cleanup_job); + cleanup_job = drm_sched_get_cleanup_job(sched); + }
if (!entity) continue;