xfs: mark XLOG_FORCED_SHUTDOWN as unlikely

A shutdown log is a slow failure path.  Add an unlikely annotation to
it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

fs/xfs/xfs_log_priv.h

@@ -402,7 +402,8 @@ struct xlog {
 #define XLOG_BUF_CANCEL_BUCKET(log, blkno) \
 	((log)->l_buf_cancel_table + ((uint64_t)blkno % XLOG_BC_TABLE_SIZE))
 
-#define XLOG_FORCED_SHUTDOWN(log)	((log)->l_flags & XLOG_IO_ERROR)
+#define XLOG_FORCED_SHUTDOWN(log) \
+	(unlikely((log)->l_flags & XLOG_IO_ERROR))
 
 /* common routines */
 extern int