The following commit has been merged in the linux branch: commit 86df7eb921a009515285e7171363fa57dd2d7d31 Author: Yan, Zheng zheng.yan@oracle.com Date: Wed Oct 14 09:24:59 2009 -0400
Btrfs: properly wait log writers during log sync
A recently fsync optimization make btrfs_sync_log skip calling wait_for_writer in the single log writer case. This is incorrect since the writer count can also be increased by btrfs_pin_log.
Signed-off-by: Yan Zheng zheng.yan@oracle.com Signed-off-by: Chris Mason chris.mason@oracle.com
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 4aff766..f51bf13 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1995,12 +1995,13 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, if (atomic_read(&root->log_commit[(index1 + 1) % 2])) wait_log_commit(trans, root, root->log_transid - 1);
- while (root->log_multiple_pids) { + while (1) { unsigned long batch = root->log_batch; - mutex_unlock(&root->log_mutex); - schedule_timeout_uninterruptible(1); - mutex_lock(&root->log_mutex); - + if (root->log_multiple_pids) { + mutex_unlock(&root->log_mutex); + schedule_timeout_uninterruptible(1); + mutex_lock(&root->log_mutex); + } wait_for_writer(trans, root); if (batch == root->log_batch) break;