drm/amdgpu: Get rid of dep_sync as a seperate object.

Instead mark fence as explicit in it's amdgpu_sync_entry.

v2:
Fix use after free bug and add new parameter description.
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index 18770a8..bdc210a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -60,7 +60,6 @@ int amdgpu_job_alloc(struct amdgpu_device *adev, unsigned num_ibs,
 	(*job)->num_ibs = num_ibs;
 
 	amdgpu_sync_create(&(*job)->sync);
-	amdgpu_sync_create(&(*job)->dep_sync);
 	amdgpu_sync_create(&(*job)->sched_sync);
 	(*job)->vram_lost_counter = atomic_read(&adev->vram_lost_counter);
 
@@ -104,7 +103,6 @@ static void amdgpu_job_free_cb(struct amd_sched_job *s_job)
 	amdgpu_ring_priority_put(job->ring, s_job->s_priority);
 	dma_fence_put(job->fence);
 	amdgpu_sync_free(&job->sync);
-	amdgpu_sync_free(&job->dep_sync);
 	amdgpu_sync_free(&job->sched_sync);
 	kfree(job);
 }
@@ -115,7 +113,6 @@ void amdgpu_job_free(struct amdgpu_job *job)
 
 	dma_fence_put(job->fence);
 	amdgpu_sync_free(&job->sync);
-	amdgpu_sync_free(&job->dep_sync);
 	amdgpu_sync_free(&job->sched_sync);
 	kfree(job);
 }
@@ -149,17 +146,18 @@ static struct dma_fence *amdgpu_job_dependency(struct amd_sched_job *sched_job,
 {
 	struct amdgpu_job *job = to_amdgpu_job(sched_job);
 	struct amdgpu_vm *vm = job->vm;
-
-	struct dma_fence *fence = amdgpu_sync_get_fence(&job->dep_sync);
+	bool explicit = false;
 	int r;
+	struct dma_fence *fence = amdgpu_sync_get_fence(&job->sync, &explicit);
 
-	if (amd_sched_dependency_optimized(fence, s_entity)) {
-		r = amdgpu_sync_fence(job->adev, &job->sched_sync, fence);
-		if (r)
-			DRM_ERROR("Error adding fence to sync (%d)\n", r);
+	if (fence && explicit) {
+		if (amd_sched_dependency_optimized(fence, s_entity)) {
+			r = amdgpu_sync_fence(job->adev, &job->sched_sync, fence, false);
+			if (r)
+				DRM_ERROR("Error adding fence to sync (%d)\n", r);
+		}
 	}
-	if (!fence)
-		fence = amdgpu_sync_get_fence(&job->sync);
+
 	while (fence == NULL && vm && !job->vm_id) {
 		struct amdgpu_ring *ring = job->ring;
 
@@ -169,7 +167,7 @@ static struct dma_fence *amdgpu_job_dependency(struct amd_sched_job *sched_job,
 		if (r)
 			DRM_ERROR("Error getting VM ID (%d)\n", r);
 
-		fence = amdgpu_sync_get_fence(&job->sync);
+		fence = amdgpu_sync_get_fence(&job->sync, NULL);
 	}
 
 	return fence;