[PATCH 02/14] repair: reduce byte swap operations in scanfunc_allocbt

Christoph Hellwig
2009-09-02T17:57:59Z

[-- Attachment #1: repair-scan.c-reduce-byteswaps --]
[-- Type: text/plain, Size: 2514 bytes --]

Store native endian version of the extent startblock and length in
local variables instead of converting them over and over again.

Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: xfsprogs-dev/repair/scan.c
===================================================================
--- xfsprogs-dev.orig/repair/scan.c 2009-08-21 18:48:01.000000000 +0000
+++ xfsprogs-dev/repair/scan.c 2009-08-21 18:54:29.000000000 +0000
@@ -449,7 +449,6 @@ scanfunc_allocbt(
__uint32_t magic)
{
const char *name;
- xfs_agblock_t b, e;
int i;
xfs_alloc_ptr_t *pp;
xfs_alloc_rec_t *rp;
@@ -509,20 +508,21 @@ _("%s freespace btree block claimed (sta

rp = XFS_ALLOC_REC_ADDR(mp, block, 1);
for (i = 0; i < numrecs; i++) {
- if (be32_to_cpu(rp[i].ar_blockcount) == 0 ||
- be32_to_cpu(rp[i].ar_startblock) == 0 ||
- !verify_agbno(mp, agno,
- be32_to_cpu(rp[i].ar_startblock)) ||
- be32_to_cpu(rp[i].ar_blockcount) >
- MAXEXTLEN)
- continue;
+ xfs_agblock_t b, end;
+ xfs_extlen_t len;
+
+ b = be32_to_cpu(rp[i].ar_startblock);
+ len = be32_to_cpu(rp[i].ar_blockcount);
+ end = b + len;

- e = be32_to_cpu(rp[i].ar_startblock) +
- be32_to_cpu(rp[i].ar_blockcount);
- if (!verify_agbno(mp, agno, e - 1))
+ if (b == 0 || !verify_agbno(mp, agno, b))
+ continue;
+ if (len == 0 || len > MAXEXTLEN)
continue;
- for (b = be32_to_cpu(rp[i].ar_startblock);
- b < e; b++) {
+ if (!verify_agbno(mp, agno, end - 1))
+ continue;
+
+ for ( ; b < end; b++) {
state = get_agbno_state(mp, agno, b);
switch (state) {
case XR_E_UNKNOWN:
@@ -579,6 +579,8 @@ _("%s freespace btree block claimed (sta
}

for (i = 0; i < numrecs; i++) {
+ xfs_agblock_t bno = be32_to_cpu(pp[i]);
+
/*
* XXX - put sibling detection right here.
* we know our sibling chain is good. So as we go,
@@ -588,11 +590,11 @@ _("%s freespace btree block claimed (sta
* pointer mismatch, try and extract as much data
* as possible.
*/
- if (be32_to_cpu(pp[i]) != 0 && verify_agbno(mp, agno,
- be32_to_cpu(pp[i])))
- scan_sbtree(be32_to_cpu(pp[i]), level, agno, suspect,
+ if (bno != 0 && verify_agbno(mp, agno, bno)) {
+ scan_sbtree(bno, level, agno, suspect,
(magic == XFS_ABTB_MAGIC) ?
scanfunc_bno : scanfunc_cnt, 0);
+ }
}
}