tree 1447ecb5ace55b30f6ed03cf47f7121cce42418f
parent 52101dfe56f71d8cb140c2440d95affa25a53746
author Dave Chinner <dchinner@redhat.com> 1525877254 -0700
committer Darrick J. Wong <darrick.wong@oracle.com> 1525967801 -0700

xfs: log item flags are racy

The log item flags contain a field that is protected by the AIL
lock - the XFS_LI_IN_AIL flag. We use non-atomic RMW operations to
set and clear these flags, but most of the updates and checks are
not done with the AIL lock held and so are susceptible to update
races.

Fix this by changing the log item flags to use atomic bitops rather
than be reliant on the AIL lock for update serialisation.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>