drm/managed: Add DRM-managed alloc_ordered_workqueue

Add drmm_alloc_ordered_workqueue(), a helper that provides managed ordered
workqueue cleanup. The workqueue will be destroyed with the final
reference of the DRM device.

Reviewed-by: Thomas Zimmermann <[email protected]>
Reviewed-by: Maxime Ripard <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Signed-off-by: Louis Chauvet <[email protected]>

Author: Fomys

drivers/gpu/drm/drm_managed.c

@@ -310,3 +310,11 @@ void __drmm_mutex_release(struct drm_device *dev, void *res)
 	mutex_destroy(lock);
 }
 EXPORT_SYMBOL(__drmm_mutex_release);
+
+void __drmm_workqueue_release(struct drm_device *device, void *res)
+{
+	struct workqueue_struct *wq = res;
+
+	destroy_workqueue(wq);
+}
+EXPORT_SYMBOL(__drmm_workqueue_release);

include/drm/drm_managed.h

@@ -127,4 +127,16 @@ void __drmm_mutex_release(struct drm_device *dev, void *res);
 	drmm_add_action_or_reset(dev, __drmm_mutex_release, lock);	     \
 })									     \
 
+void __drmm_workqueue_release(struct drm_device *device, void *wq);
+
+#define drmm_alloc_ordered_workqueue(dev, fmt, flags, args...)					\
+	({											\
+		struct workqueue_struct *wq = alloc_ordered_workqueue(fmt, flags, ##args);	\
+		wq ? ({										\
+			int ret = drmm_add_action_or_reset(dev, __drmm_workqueue_release, wq);	\
+			ret ? ERR_PTR(ret) : wq;						\
+		}) :										\
+			wq;									\
+	})
+
 #endif