blk-cgroup: move locking into blkg_destroy_all

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 717ab38..3ba23b9 100644 (file)
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -349,8 +349,7 @@ static void blkg_destroy_all(struct request_queue *q)
 {
        struct blkcg_gq *blkg, *n;
 
-       lockdep_assert_held(q->queue_lock);
-
+       spin_lock_irq(q->queue_lock);
        list_for_each_entry_safe(blkg, n, &q->blkg_list, q_node) {
                struct blkcg *blkcg = blkg->blkcg;
 
@@ -360,6 +359,7 @@ static void blkg_destroy_all(struct request_queue *q)
        }
 
        q->root_blkg = NULL;
+       spin_unlock_irq(q->queue_lock);
 }
 
 /*
@@ -1182,9 +1182,7 @@ int blkcg_init_queue(struct request_queue *q)
        return 0;
 
 err_destroy_all:
-       spin_lock_irq(q->queue_lock);
        blkg_destroy_all(q);
-       spin_unlock_irq(q->queue_lock);
        return ret;
 err_unlock:
        spin_unlock_irq(q->queue_lock);
@@ -1222,10 +1220,7 @@ void blkcg_drain_queue(struct request_queue *q)
  */
 void blkcg_exit_queue(struct request_queue *q)
 {
-       spin_lock_irq(q->queue_lock);
        blkg_destroy_all(q);
-       spin_unlock_irq(q->queue_lock);
-
        blk_throtl_exit(q);
 }