[XFS] Fix inode allocation latency

The log force added in xfs_iget_core() has been a performance issue since
it was introduced for tight loops that allocate then unlink a single file.
under heavy writeback, this can introduce unnecessary latency due tothe
log I/o getting stuck behind bulk data writes.

Fix this latency problem by avoinding the need for the log force by moving
the place we mark linux inode dirty to the transaction commit rather than
on transaction completion.

This also closes a potential hole in the sync code where a linux inode is
not dirty between the time it is modified and the time the log buffer has
been written to disk.

SGI-PV: 972753
SGI-Modid: xfs-linux-melb:xfs-kern:30007a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index d8ed51e28cbb..bc869fd2f6ef 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -532,6 +532,7 @@ xfs_fsize_t	xfs_file_last_byte(xfs_inode_t *);
 void            xfs_lock_inodes(xfs_inode_t **, int, int, uint);
 
 void            xfs_synchronize_atime(xfs_inode_t *);
+void            xfs_mark_inode_dirty_sync(xfs_inode_t *);
 
 xfs_bmbt_rec_host_t *xfs_iext_get_ext(xfs_ifork_t *, xfs_extnum_t);
 void            xfs_iext_insert(xfs_ifork_t *, xfs_extnum_t, xfs_extnum_t,