From: Fanjun Kong <bh1scw@xxxxxxxxx> spin_lock_irq/spin_unlock_irq contains preempt_disable/enable(). Which can serve as RCU read-side critical region, so remove rcu_read_lock/unlock(). Signed-off-by: Fanjun Kong <bh1scw@xxxxxxxxx> --- block/blk-cgroup.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index a91f8ae18b49..7bdc16a36560 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1283,14 +1283,13 @@ int blkcg_init_queue(struct request_queue *q) preloaded = !radix_tree_preload(GFP_KERNEL); /* Make sure the root blkg exists. */ - rcu_read_lock(); + /* spin_lock_irq can serve as RCU read-side critical section. */ spin_lock_irq(&q->queue_lock); blkg = blkg_create(&blkcg_root, q, new_blkg); if (IS_ERR(blkg)) goto err_unlock; q->root_blkg = blkg; spin_unlock_irq(&q->queue_lock); - rcu_read_unlock(); if (preloaded) radix_tree_preload_end(); @@ -1316,7 +1315,6 @@ int blkcg_init_queue(struct request_queue *q) return ret; err_unlock: spin_unlock_irq(&q->queue_lock); - rcu_read_unlock(); if (preloaded) radix_tree_preload_end(); return PTR_ERR(blkg); -- 2.36.0
