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_ialloc.c b/fs/xfs/xfs_ialloc.c
index 84ebeec..dd5628b 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -683,7 +683,7 @@
 			return 0;
 		}
 		agi = XFS_BUF_TO_AGI(agbp);
-		ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
+		ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
 	} else {
 		/*
 		 * Continue where we left off before.  In this case, we
@@ -691,7 +691,7 @@
 		 */
 		agbp = *IO_agbp;
 		agi = XFS_BUF_TO_AGI(agbp);
-		ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
+		ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
 		ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
 	}
 	mp = tp->t_mountp;
@@ -775,7 +775,7 @@
 		if (error)
 			goto nextag;
 		agi = XFS_BUF_TO_AGI(agbp);
-		ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
+		ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
 	}
 	/*
 	 * Here with an allocation group that has a free inode.
@@ -944,7 +944,7 @@
 	 * See if the most recently allocated block has any free.
 	 */
 newino:
-	if (be32_to_cpu(agi->agi_newino) != NULLAGINO) {
+	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
 		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
 					 XFS_LOOKUP_EQ, &i);
 		if (error)
@@ -1085,7 +1085,7 @@
 		return error;
 	}
 	agi = XFS_BUF_TO_AGI(agbp);
-	ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
+	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
 	ASSERT(agbno < be32_to_cpu(agi->agi_length));
 	/*
 	 * Initialize the cursor.
@@ -1438,7 +1438,7 @@
 	xfs_agi_t		*agi;	/* allocation group header */
 
 	agi = XFS_BUF_TO_AGI(bp);
-	ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
+	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
 #endif
 	/*
 	 * Compute byte offsets for the first and last fields.
@@ -1492,7 +1492,7 @@
 	/*
 	 * Validate the magic number of the agi block.
 	 */
-	agi_ok = be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC &&
+	agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) &&
 		XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) &&
 		be32_to_cpu(agi->agi_seqno) == agno;
 	if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,