At 10/19/2016 10:31 PM, David Sterba wrote:
On Fri, Sep 30, 2016 at 09:15:36AM +0800, Qu Wenruo wrote:While the reason why qgroup reserved space may underflow is still under investigation, such WARN_ON will help us to expose the bug more easily, and for end-user we can detect and avoid underflow. Signed-off-by: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx> --- fs/btrfs/qgroup.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 8db2e29..8532587 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -1061,8 +1061,12 @@ static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info, WARN_ON(sign < 0 && qgroup->excl < num_bytes); qgroup->excl += sign * num_bytes; qgroup->excl_cmpr += sign * num_bytes; - if (sign > 0) - qgroup->reserved -= num_bytes; + if (sign > 0) { + if (WARN_ON(qgroup->reserved < num_bytes))That's only partially helpful, you should also print the numbers, ref_root and/or qgroup id.
I'm OK to add more output. But normally it's not really help though. Thanks, Qu -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
