Btrfs: wrap repeated code into scrub_blocked_if_needed()
Just wrap same code into one function scrub_blocked_if_needed().
This make a change that we will move waiting (@workers_pending = 0)
before we can wake up commiting transaction(atomic_inc(@scrub_paused)),
we must take carefully to not deadlock here.
Thread 1 Thread 2
|->btrfs_commit_transaction()
|->set trans type(COMMIT_DOING)
|->btrfs_scrub_paused()(blocked)
|->join_transaction(blocked)
Move btrfs_scrub_paused() before setting trans type which means we can
still join a transaction when commiting_transaction is blocked.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Suggested-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 1451637..026f1fe 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1748,6 +1748,8 @@
goto cleanup_transaction;
btrfs_wait_delalloc_flush(root->fs_info);
+
+ btrfs_scrub_pause(root);
/*
* Ok now we need to make sure to block out any other joins while we
* commit the transaction. We could have started a join before setting
@@ -1812,7 +1814,6 @@
WARN_ON(cur_trans != trans->transaction);
- btrfs_scrub_pause(root);
/* btrfs_commit_tree_roots is responsible for getting the
* various roots consistent with each other. Every pointer
* in the tree of tree roots has to point to the most up to date