When a task trying to double lock a extent buffer, there are no lockdep warning about it because this lock may be in "blocking_lock" state, and make us hard to debug.
This patch add a WARN_ON() for above condition, it can not report all deadlock cases(as lock between tasks), but at least helps us some. Signed-off-by: Zhao Lei <zhao...@cn.fujitsu.com> --- fs/btrfs/locking.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index f8229ef..d7e6baf 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -241,6 +241,7 @@ void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb) */ void btrfs_tree_lock(struct extent_buffer *eb) { + WARN_ON(eb->lock_owner == current->pid); again: wait_event(eb->read_lock_wq, atomic_read(&eb->blocking_readers) == 0); wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0); -- 1.8.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html