drm/lima: use scheduler dependency tracking

Nothing special going on here.

Aside reviewing the code, it seems like drm_sched_job_arm() should be
moved into lima_sched_context_queue_task and put under some mutex
together with drm_sched_push_job(). See the kerneldoc for
drm_sched_push_job().

v2: Rebase over renamed functions to add dependencies.
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Qiang Yu <yuq825@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: lima@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210805104705.862416-9-daniel.vetter@ffwll.ch

drivers/gpu/drm/lima/lima_gem.c

@@ -267,7 +267,9 @@ static int lima_gem_sync_bo(struct lima_sched_task *task, struct lima_bo *bo,
 	if (explicit)
 		return 0;
 
-	return drm_gem_fence_array_add_implicit(&task->deps, &bo->base.base, write);
+	return drm_sched_job_add_implicit_dependencies(&task->base,
+						       &bo->base.base,
+						       write);
 }
 
 static int lima_gem_add_deps(struct drm_file *file, struct lima_submit *submit)
@@ -285,7 +287,7 @@ static int lima_gem_add_deps(struct drm_file *file, struct lima_submit *submit)
 		if (err)
 			return err;
 
-		err = drm_gem_fence_array_add(&submit->task->deps, fence);
+		err = drm_sched_job_add_dependency(&submit->task->base, fence);
 		if (err) {
 			dma_fence_put(fence);
 			return err;

drivers/gpu/drm/lima/lima_sched.c

@@ -134,24 +134,15 @@ int lima_sched_task_init(struct lima_sched_task *task,
 	task->num_bos = num_bos;
 	task->vm = lima_vm_get(vm);
 
-	xa_init_flags(&task->deps, XA_FLAGS_ALLOC);
-
 	return 0;
 }
 
 void lima_sched_task_fini(struct lima_sched_task *task)
 {
-	struct dma_fence *fence;
-	unsigned long index;
 	int i;
 
 	drm_sched_job_cleanup(&task->base);
 
-	xa_for_each(&task->deps, index, fence) {
-		dma_fence_put(fence);
-	}
-	xa_destroy(&task->deps);
-
 	if (task->bos) {
 		for (i = 0; i < task->num_bos; i++)
 			drm_gem_object_put(&task->bos[i]->base.base);
@@ -186,17 +177,6 @@ struct dma_fence *lima_sched_context_queue_task(struct lima_sched_task *task)
 	return fence;
 }
 
-static struct dma_fence *lima_sched_dependency(struct drm_sched_job *job,
-					       struct drm_sched_entity *entity)
-{
-	struct lima_sched_task *task = to_lima_task(job);
-
-	if (!xa_empty(&task->deps))
-		return xa_erase(&task->deps, task->last_dep++);
-
-	return NULL;
-}
-
 static int lima_pm_busy(struct lima_device *ldev)
 {
 	int ret;
@@ -472,7 +452,6 @@ static void lima_sched_free_job(struct drm_sched_job *job)
 }
 
 static const struct drm_sched_backend_ops lima_sched_ops = {
-	.dependency = lima_sched_dependency,
 	.run_job = lima_sched_run_job,
 	.timedout_job = lima_sched_timedout_job,
 	.free_job = lima_sched_free_job,

drivers/gpu/drm/lima/lima_sched.h

@@ -23,9 +23,6 @@ struct lima_sched_task {
 	struct lima_vm *vm;
 	void *frame;
 
-	struct xarray deps;
-	unsigned long last_dep;
-
 	struct lima_bo **bos;
 	int num_bos;