amdgpu/dc: convert dc_transfer to use a kref.

Rolling your own atomic ref counts is frowned upon.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 9 insertions, 8 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_surface.c b/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
index ff07105bfd99..c2168dfacc8d 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
@@ -161,17 +161,18 @@ alloc_fail:
 
 void dc_transfer_func_retain(struct dc_transfer_func *tf)
 {
-	ASSERT(atomic_read(&tf->ref_count) > 0);
-	atomic_inc(&tf->ref_count);
+	kref_get(&tf->refcount);
 }
 
-void dc_transfer_func_release(struct dc_transfer_func *tf)
+static void dc_transfer_func_free(struct kref *kref)
 {
-	ASSERT(atomic_read(&tf->ref_count) > 0);
-	atomic_dec(&tf->ref_count);
+	struct dc_transfer_func *tf = container_of(kref, struct dc_transfer_func, refcount);
+	kfree(tf);
+}
 
-	if (atomic_read(&tf->ref_count) == 0)
-		kfree(tf);
+void dc_transfer_func_release(struct dc_transfer_func *tf)
+{
+	kref_put(&tf->refcount, dc_transfer_func_free);
 }
 
 struct dc_transfer_func *dc_create_transfer_func()
@@ -181,7 +182,7 @@ struct dc_transfer_func *dc_create_transfer_func()
 	if (tf == NULL)
 		goto alloc_fail;
 
-	atomic_inc(&tf->ref_count);
+	kref_init(&tf->refcount);
 
 	return tf;