linux-kernel - [PATCH] ext4: remove unnecessary code in __mb_check

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Date:   Mon,  4 Apr 2022 23:22:43 +0800
From:   Jinke Han <hanjinke.666@...edance.com>
To:     tytso@....edu, adilger.kernel@...ger.ca
Cc:     linux-ext4@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jinke Han <hanjinke.666@...edance.com>
Subject: [PATCH] ext4: remove unnecessary code in __mb_check_buddy

From: Jinke Han <hanjinke.666@...edance.com>

When enter elseif branch, the the MB_CHECK_ASSERT will never fail.
In addtion, the only illegal combination is 0/0, which can be caught
by the first if branch.

Signed-off-by: Jinke Han <hanjinke.666@...edance.com>
---
 fs/ext4/mballoc.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index e5d43d2ee474..eba650b31870 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -576,13 +576,10 @@ static int __mb_check_buddy(struct ext4_buddy *e4b, char *file,
 		for (i = 0; i < max; i++) {
 
 			if (mb_test_bit(i, buddy)) {
-				/* only single bit in buddy2 may be 1 */
+				/* only single bit in buddy2 may be 0 */
 				if (!mb_test_bit(i << 1, buddy2)) {
 					MB_CHECK_ASSERT(
 						mb_test_bit((i<<1)+1, buddy2));
-				} else if (!mb_test_bit((i << 1) + 1, buddy2)) {
-					MB_CHECK_ASSERT(
-						mb_test_bit(i << 1, buddy2));
 				}
 				continue;
 			}
-- 
2.20.1