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>

1 files changed, 32 insertions, 27 deletions

diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index 5d2651f1c759..d629b888ca28 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -201,8 +201,8 @@ xfs_dir2_leaf_find_entry(
                  */
                 for (lowstale = index - 1;
                      lowstale >= 0 &&
-                        be32_to_cpu(leaf->ents[lowstale].address) !=
-                        XFS_DIR2_NULL_DATAPTR;
+                        leaf->ents[lowstale].address !=
+                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
                      lowstale--)
                         continue;
 
@@ -213,8 +213,8 @@ xfs_dir2_leaf_find_entry(
                  */
                 for (highstale = index;
                      highstale < be16_to_cpu(leaf->hdr.count) &&
-                        be32_to_cpu(leaf->ents[highstale].address) !=
-                        XFS_DIR2_NULL_DATAPTR &&
+                        leaf->ents[highstale].address !=
+                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR) &&
                         (lowstale < 0 ||
                          index - lowstale - 1 >= highstale - index);
                      highstale++)
@@ -228,8 +228,8 @@ xfs_dir2_leaf_find_entry(
             (highstale == be16_to_cpu(leaf->hdr.count) ||
              index - lowstale - 1 < highstale - index)) {
                 ASSERT(index - lowstale - 1 >= 0);
-                ASSERT(be32_to_cpu(leaf->ents[lowstale].address) ==
-                       XFS_DIR2_NULL_DATAPTR);
+                ASSERT(leaf->ents[lowstale].address ==
+                       cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 
                 /*
                  * Copy entries up to cover the stale entry and make room
@@ -251,8 +251,8 @@ xfs_dir2_leaf_find_entry(
          * The high one is better, so use that one.
          */
         ASSERT(highstale - index >= 0);
-        ASSERT(be32_to_cpu(leaf->ents[highstale].address) ==
-               XFS_DIR2_NULL_DATAPTR);
+        ASSERT(leaf->ents[highstale].address ==
+               cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 
         /*
          * Copy entries down to cover the stale entry and make room for the
@@ -342,7 +342,7 @@ xfs_dir2_leaf_addname(
                         continue;
                 i = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
                 ASSERT(i < be32_to_cpu(ltp->bestcount));
-                ASSERT(be16_to_cpu(bestsp[i]) != NULLDATAOFF);
+                ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
                 if (be16_to_cpu(bestsp[i]) >= length) {
                         use_block = i;
                         break;
@@ -356,7 +356,8 @@ xfs_dir2_leaf_addname(
                         /*
                          * Remember a block we see that's missing.
                          */
-                        if (be16_to_cpu(bestsp[i]) == NULLDATAOFF && use_block == -1)
+                        if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
+                            use_block == -1)
                                 use_block = i;
                         else if (be16_to_cpu(bestsp[i]) >= length) {
                                 use_block = i;
@@ -377,7 +378,7 @@ xfs_dir2_leaf_addname(
          * Now kill use_block if it refers to a missing block, so we
          * can use it as an indication of allocation needed.
          */
-        if (use_block != -1 && be16_to_cpu(bestsp[use_block]) == NULLDATAOFF)
+        if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
                 use_block = -1;
         /*
          * If we don't have enough free bytes but we can make enough
@@ -590,7 +591,7 @@ xfs_dir2_leaf_check(
 
         leaf = bp->data;
         mp = dp->i_mount;
-        ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
+        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
         /*
          * This value is not restrictive enough.
          * Should factor in the size of the bests table as well.
@@ -610,7 +611,7 @@ xfs_dir2_leaf_check(
                 if (i + 1 < be16_to_cpu(leaf->hdr.count))
                         ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
                                be32_to_cpu(leaf->ents[i + 1].hashval));
-                if (be32_to_cpu(leaf->ents[i].address) == XFS_DIR2_NULL_DATAPTR)
+                if (leaf->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
                         stale++;
         }
         ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
@@ -639,7 +640,8 @@ xfs_dir2_leaf_compact(
          * Compress out the stale entries in place.
          */
         for (from = to = 0, loglow = -1; from < be16_to_cpu(leaf->hdr.count); from++) {
-                if (be32_to_cpu(leaf->ents[from].address) == XFS_DIR2_NULL_DATAPTR)
+                if (leaf->ents[from].address ==
+                    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
                         continue;
                 /*
                  * Only actually copy the entries that are different.
@@ -696,7 +698,8 @@ xfs_dir2_leaf_compact_x1(
          */
         for (lowstale = index - 1;
              lowstale >= 0 &&
-                be32_to_cpu(leaf->ents[lowstale].address) != XFS_DIR2_NULL_DATAPTR;
+                leaf->ents[lowstale].address !=
+                cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
              lowstale--)
                 continue;
         /*
@@ -705,7 +708,8 @@ xfs_dir2_leaf_compact_x1(
          */
         for (highstale = index;
              highstale < be16_to_cpu(leaf->hdr.count) &&
-                be32_to_cpu(leaf->ents[highstale].address) != XFS_DIR2_NULL_DATAPTR &&
+                leaf->ents[highstale].address !=
+                cpu_to_be32(XFS_DIR2_NULL_DATAPTR) &&
                 (lowstale < 0 || index - lowstale > highstale - index);
              highstale++)
                 continue;
@@ -729,7 +733,8 @@ xfs_dir2_leaf_compact_x1(
                 if (index == from)
                         newindex = to;
                 if (from != keepstale &&
-                    be32_to_cpu(leaf->ents[from].address) == XFS_DIR2_NULL_DATAPTR) {
+                    leaf->ents[from].address ==
+                    cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
                         if (from == to)
                                 *lowlogp = to;
                         continue;
@@ -1207,7 +1212,7 @@ xfs_dir2_leaf_log_bests(
         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 
         leaf = bp->data;
-        ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
+        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
         ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
@@ -1230,8 +1235,8 @@ xfs_dir2_leaf_log_ents(
         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 
         leaf = bp->data;
-        ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC ||
-               be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
+        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
+               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
         firstlep = &leaf->ents[first];
         lastlep = &leaf->ents[last];
         xfs_da_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
@@ -1249,8 +1254,8 @@ xfs_dir2_leaf_log_header(
         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 
         leaf = bp->data;
-        ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC ||
-               be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
+        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
+               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
         xfs_da_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
                 (uint)(sizeof(leaf->hdr) - 1));
 }
@@ -1269,7 +1274,7 @@ xfs_dir2_leaf_log_tail(
 
         mp = tp->t_mountp;
         leaf = bp->data;
-        ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
+        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
         xfs_da_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
                 (uint)(mp->m_dirblksize - 1));
@@ -1570,7 +1575,7 @@ xfs_dir2_leaf_removename(
                          * Look for the last active entry (i).
                          */
                         for (i = db - 1; i > 0; i--) {
-                                if (be16_to_cpu(bestsp[i]) != NULLDATAOFF)
+                                if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
                                         break;
                         }
                         /*
@@ -1740,7 +1745,7 @@ xfs_dir2_leaf_trim_data(
 {
         struct xfs_dir2_data_hdr *hdr = dbp->data;
 
-        ASSERT(be32_to_cpu(hdr->magic) == XFS_DIR2_DATA_MAGIC);
+        ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
         ASSERT(be16_to_cpu(hdr->bestfree[0].length) ==
                mp->m_dirblksize - (uint)sizeof(*hdr));
         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
@@ -1850,7 +1855,7 @@ xfs_dir2_node_to_leaf(
                 return 0;
         lbp = state->path.blk[0].bp;
         leaf = lbp->data;
-        ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
+        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
         /*
          * Read the freespace block.
          */
@@ -1859,7 +1864,7 @@ xfs_dir2_node_to_leaf(
                 return error;
         }
         free = fbp->data;
-        ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
+        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
         ASSERT(!free->hdr.firstdb);
 
         /*