diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index 93146b495276..c84c650e56c7 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -128,20 +128,21 @@ void btrfs_tree_read_lock(struct extent_buffer *eb) read_lock(&eb->lock); BUG_ON(eb->blocking_writers == 0 && current->pid == eb->lock_owner); - if (eb->blocking_writers && current->pid == eb->lock_owner) { - /* - * This extent is already write-locked by our thread. We allow - * an additional read lock to be added because it's for the same - * thread. btrfs_find_all_roots() depends on this as it may be - * called on a partly (write-)locked tree. - */ - BUG_ON(eb->lock_nested); - eb->lock_nested = true; - read_unlock(&eb->lock); - trace_btrfs_tree_read_lock(eb, start_ns); - return; - } if (eb->blocking_writers) { + if (current->pid == eb->lock_owner) { + /* + * This extent is already write-locked by our thread. + * We allow an additional read lock to be added because + * it's for the same thread. btrfs_find_all_roots() + * depends on this as it may be called on a partly + * (write-)locked tree. + */ + BUG_ON(eb->lock_nested); + eb->lock_nested = true; + read_unlock(&eb->lock); + trace_btrfs_tree_read_lock(eb, start_ns); + return; + } read_unlock(&eb->lock); wait_event(eb->write_lock_wq, eb->blocking_writers == 0);