Btrfs: Add ACCESS_ONCE() to transaction->abort accesses
We may access and update transaction->aborted on the different CPUs without
lock, so we need ACCESS_ONCE() wrapper to prevent the compiler from creating
unsolicited accesses and make sure we can get the right value.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 99545df..d8982e9 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -267,7 +267,7 @@
function, line, errstr);
return;
}
- trans->transaction->aborted = errno;
+ ACCESS_ONCE(trans->transaction->aborted) = errno;
__btrfs_std_error(root->fs_info, function, line, errno, NULL);
}
/*
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 87fac9a..0ef2961 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1468,7 +1468,8 @@
goto cleanup_transaction;
}
- if (cur_trans->aborted) {
+ /* Stop the commit early if ->aborted is set */
+ if (unlikely(ACCESS_ONCE(cur_trans->aborted))) {
ret = cur_trans->aborted;
goto cleanup_transaction;
}