[PATCH 1/2] drm/amdgpu: change job_list_lock to mutex

[Chunming Zhou]

ring_mirror_list is only used kthread context, no need to spinlock.
otherwise deadlock happens when kthread_park.

Change-Id: I906022297015faf14a0ddb5f62a728af3e5f9448
Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>
---
 drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 12 +++++-------
 drivers/gpu/drm/amd/scheduler/gpu_scheduler.h |  2 +-
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
index b53cf58..3373d97 100644
--- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
+++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
@@ -331,10 +331,9 @@ static void amd_sched_job_finish(struct work_struct *work)
 	struct amd_sched_job *s_job = container_of(work, struct amd_sched_job,
 						   finish_work);
 	struct amd_gpu_scheduler *sched = s_job->sched;
-	unsigned long flags;
 
 	/* remove job from ring_mirror_list */
-	spin_lock_irqsave(&sched->job_list_lock, flags);
+	mutex_lock(&sched->job_list_lock);
 	list_del_init(&s_job->node);
 	if (sched->timeout != MAX_SCHEDULE_TIMEOUT) {
 		struct amd_sched_job *next;
@@ -348,7 +347,7 @@ static void amd_sched_job_finish(struct work_struct *work)
 		if (next)
 			schedule_delayed_work(&next->work_tdr, sched->timeout);
 	}
-	spin_unlock_irqrestore(&sched->job_list_lock, flags);
+	mutex_unlock(&sched->job_list_lock);
 	sched->ops->free_job(s_job);
 }
 
@@ -362,15 +361,14 @@ static void amd_sched_job_finish_cb(struct fence *f, struct fence_cb *cb)
 static void amd_sched_job_begin(struct amd_sched_job *s_job)
 {
 	struct amd_gpu_scheduler *sched = s_job->sched;
-	unsigned long flags;
 
-	spin_lock_irqsave(&sched->job_list_lock, flags);
+	mutex_lock(&sched->job_list_lock);
 	list_add_tail(&s_job->node, &sched->ring_mirror_list);
 	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
 	    list_first_entry_or_null(&sched->ring_mirror_list,
 				     struct amd_sched_job, node) == s_job)
 		schedule_delayed_work(&s_job->work_tdr, sched->timeout);
-	spin_unlock_irqrestore(&sched->job_list_lock, flags);
+	mutex_unlock(&sched->job_list_lock);
 }
 
 static void amd_sched_job_timedout(struct work_struct *work)
@@ -564,7 +562,7 @@ int amd_sched_init(struct amd_gpu_scheduler *sched,
 	init_waitqueue_head(&sched->wake_up_worker);
 	init_waitqueue_head(&sched->job_scheduled);
 	INIT_LIST_HEAD(&sched->ring_mirror_list);
-	spin_lock_init(&sched->job_list_lock);
+	mutex_init(&sched->job_list_lock);
 	atomic_set(&sched->hw_rq_count, 0);
 	if (atomic_inc_return(&sched_fence_slab_ref) == 1) {
 		sched_fence_slab = kmem_cache_create(
diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
index 221a515..5675906 100644
--- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
+++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
@@ -132,7 +132,7 @@ struct amd_gpu_scheduler {
 	atomic_t			hw_rq_count;
 	struct task_struct		*thread;
 	struct list_head	ring_mirror_list;
-	spinlock_t			job_list_lock;
+	struct mutex			job_list_lock;
 };
 
 int amd_sched_init(struct amd_gpu_scheduler *sched,
-- 
1.9.1