From: Theodore Ts'o <tytso@mit.edu>
Date: Sun, 11 Mar 2012 18:15:19 +0000 (-0400)
Subject: e2fsck: optimize CPU usage in check_{block,inode}_bitmaps()
X-Git-Tag: v1.42.2~36
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d2c9c42a0b1c0776afe47c9bfbddbc170d8aa036;p=thirdparty%2Fe2fsprogs.git

e2fsck: optimize CPU usage in check_{block,inode}_bitmaps()

The boolean expression (!skip_group || csum_flag) is always true,
since if csum_flag is FALSE, skip_group must also be FALSE.  Hence, we
can just remove the expression from the conditional altogether, thus
simplifying the code and making it easier to read/understand.

Also, in the case where the bit is set in the bitmap, there's no point
repeatedly setting first_free to be ext2fs_block_count(fs->super).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/e2fsck/pass5.c b/e2fsck/pass5.c
index e25f0804e..c121d92b1 100644
--- a/e2fsck/pass5.c
+++ b/e2fsck/pass5.c
@@ -372,15 +372,14 @@ redo_counts:
 		ctx->options &= ~E2F_OPT_DISCARD;
 
 	do_counts:
-		if (!bitmap && (!skip_group || csum_flag)) {
+		if (!bitmap) {
 			group_free++;
 			free_blocks++;
 			if (first_free > i)
 				first_free = i;
-		} else {
-			if (i > first_free)
-				e2fsck_discard_blocks(ctx, first_free,
-						      (i - first_free));
+		} else if (i > first_free) {
+			e2fsck_discard_blocks(ctx, first_free,
+					      (i - first_free));
 			first_free = ext2fs_blocks_count(fs->super);
 		}
 		blocks ++;
@@ -627,7 +626,7 @@ do_counts:
 						      inodes - first_free);
 				first_free = fs->super->s_inodes_per_group + 1;
 			}
-		} else if (!skip_group || csum_flag) {
+		} else {
 			group_free++;
 			free_inodes++;
 			if (first_free > inodes)