Add btrfs_end_transaction_throttle to force writers to wait for pending commits
The existing throttle mechanism was often not sufficient to prevent
new writers from coming in and making a given transaction run forever.
This adds an explicit wait at the end of most operations so they will
allow the current transaction to close.
There is no wait inside file_write, inode updates, or cow filling, all which
have different deadlock possibilities.
This is a temporary measure until better asynchronous commit support is
added. This code leads to stalls as it waits for data=ordered
writeback, and it really needs to be fixed.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index cf27b59..bbba335 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -855,10 +855,9 @@
btrfs_del_ordered_inode(inode, 1);
}
- btrfs_end_transaction(trans, root);
+ btrfs_end_transaction_throttle(trans, root);
fail:
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
return ret;
}
@@ -889,10 +888,9 @@
}
nr = trans->blocks_used;
- ret = btrfs_end_transaction(trans, root);
+ ret = btrfs_end_transaction_throttle(trans, root);
fail:
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
if (ret && !err)
err = ret;
@@ -1871,14 +1869,13 @@
btrfs_update_inode_block_group(trans, dir);
out_unlock:
nr = trans->blocks_used;
- btrfs_end_transaction(trans, root);
+ btrfs_end_transaction_throttle(trans, root);
fail:
if (drop_inode) {
inode_dec_link_count(inode);
iput(inode);
}
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
return err;
}
@@ -1936,14 +1933,13 @@
btrfs_update_inode_block_group(trans, dir);
out_unlock:
nr = trans->blocks_used;
- btrfs_end_transaction(trans, root);
+ btrfs_end_transaction_throttle(trans, root);
fail:
if (drop_inode) {
inode_dec_link_count(inode);
iput(inode);
}
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
return err;
}
@@ -1985,14 +1981,13 @@
drop_inode = 1;
nr = trans->blocks_used;
- btrfs_end_transaction(trans, root);
+ btrfs_end_transaction_throttle(trans, root);
fail:
if (drop_inode) {
inode_dec_link_count(inode);
iput(inode);
}
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
return err;
}
@@ -2055,13 +2050,12 @@
out_fail:
nr = trans->blocks_used;
- btrfs_end_transaction(trans, root);
+ btrfs_end_transaction_throttle(trans, root);
out_unlock:
if (drop_on_err)
iput(inode);
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
return err;
}
@@ -2587,10 +2581,9 @@
btrfs_update_inode(trans, root, inode);
nr = trans->blocks_used;
- ret = btrfs_end_transaction(trans, root);
+ ret = btrfs_end_transaction_throttle(trans, root);
BUG_ON(ret);
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
}
/*
@@ -2912,14 +2905,13 @@
out_unlock:
nr = trans->blocks_used;
- btrfs_end_transaction(trans, root);
+ btrfs_end_transaction_throttle(trans, root);
out_fail:
if (drop_inode) {
inode_dec_link_count(inode);
iput(inode);
}
btrfs_btree_balance_dirty(root, nr);
- btrfs_throttle(root);
return err;
}
