xfs: byteswap constants instead of variables

Micro-optimize various comparisms by always byteswapping the constant
instead of the variable, which allows to do the swap at compile instead
of runtime.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 41d5b8f..5b24a71 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -3521,13 +3521,13 @@
 	spin_unlock(&log->l_icloglock);
 
 	/* check log magic numbers */
-	if (be32_to_cpu(iclog->ic_header.h_magicno) != XLOG_HEADER_MAGIC_NUM)
+	if (iclog->ic_header.h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
 		xfs_emerg(log->l_mp, "%s: invalid magic num", __func__);
 
 	ptr = (xfs_caddr_t) &iclog->ic_header;
 	for (ptr += BBSIZE; ptr < ((xfs_caddr_t)&iclog->ic_header) + count;
 	     ptr += BBSIZE) {
-		if (be32_to_cpu(*(__be32 *)ptr) == XLOG_HEADER_MAGIC_NUM)
+		if (*(__be32 *)ptr == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
 			xfs_emerg(log->l_mp, "%s: unexpected magic num",
 				__func__);
 	}