From: Barry Naujok <bnaujok@sgi.com>
Date: Tue, 13 Oct 2009 22:29:23 +0000 (+0200)
Subject: repair: reduce byte swap operations in scanfunc_allocbt
X-Git-Tag: v3.0.5~11^2~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=08382cf4b83133dd602c83daf8bbd50740bca4ac;p=thirdparty%2Fxfsprogs-dev.git

repair: reduce byte swap operations in scanfunc_allocbt

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>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
---

diff --git a/repair/scan.c b/repair/scan.c
index f9915bb8e..2196f8152 100644
--- a/repair/scan.c
+++ b/repair/scan.c
@@ -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;
@@ -511,20 +510,21 @@ _("%s freespace btree block claimed (state %d), agno %d, bno %d, suspect %d\n"),
 
 		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:
@@ -581,6 +581,8 @@ _("%s freespace btree block claimed (state %d), agno %d, bno %d, suspect %d\n"),
 	}
 
 	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,
@@ -590,11 +592,11 @@ _("%s freespace btree block claimed (state %d), agno %d, bno %d, suspect %d\n"),
 		 * 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);
+		}
 	}
 }