On 8/16/19 6:55 AM, Ming Lei wrote:
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 977c659dcd18..46f033b48917 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -1021,6 +1021,7 @@ EXPORT_SYMBOL_GPL(blk_register_queue);
void blk_unregister_queue(struct gendisk *disk)
{
struct request_queue *q = disk->queue;
+ bool has_elevator;
if (WARN_ON(!q))
return;
@@ -1035,8 +1036,9 @@ void blk_unregister_queue(struct gendisk *disk)
* concurrent elv_iosched_store() calls.
*/
mutex_lock(&q->sysfs_lock);
-
blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q);
+ has_elevator = q->elevator;
+ mutex_unlock(&q->sysfs_lock);
blk_queue_flag_clear() modifies queue flags atomically so no need to
hold sysfs_lock around calls of that function.
@@ -1044,16 +1046,13 @@ void blk_unregister_queue(struct gendisk *disk)
*/
if (queue_is_mq(q))
blk_mq_unregister_dev(disk_to_dev(disk), q);
- mutex_unlock(&q->sysfs_lock);
kobject_uevent(&q->kobj, KOBJ_REMOVE);
kobject_del(&q->kobj);
blk_trace_remove_sysfs(disk_to_dev(disk));
- mutex_lock(&q->sysfs_lock);
- if (q->elevator)
+ if (has_elevator)
elv_unregister_queue(q);
- mutex_unlock(&q->sysfs_lock);
Have you considered to move the q->elevator check into
elv_unregister_queue() such that no new 'has_elevator' variable has to
be introduced in this function?
Thanks,
Bart.
