linux-ext4 - [PATCH] ext4: make mb_check

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Date:   Mon, 28 Sep 2020 19:36:35 +0800
From:   Chunguang Xu <brookxu.cn@...il.com>
To:     adilger.kernel@...ger.ca, tytso@....edu
Cc:     linux-ext4@...r.kernel.org
Subject: [PATCH] ext4: make mb_check_counter per group

From: Chunguang Xu <brookxu@...cent.com>

Make bb_check_counter per group, so each group has the same chance
to be checked, which can expose errors more easily.

Signed-off-by: Chunguang Xu <brookxu@...cent.com>
---
 fs/ext4/ext4.h    | 3 +++
 fs/ext4/mballoc.c | 7 ++-----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 523e00d..b883a78 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3153,6 +3153,9 @@ int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
 
 struct ext4_group_info {
 	unsigned long   bb_state;
+#ifdef AGGRESSIVE_CHECK
+	unsigned long	bb_check_counter;
+#endif
 	struct rb_root  bb_free_root;
 	ext4_grpblk_t	bb_first_free;	/* first free block */
 	ext4_grpblk_t	bb_free;	/* total free blocks */
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 6487d5c..2705a4c 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -619,11 +619,8 @@ static int __mb_check_buddy(struct ext4_buddy *e4b, char *file,
 	void *buddy;
 	void *buddy2;
 
-	{
-		static int mb_check_counter;
-		if (mb_check_counter++ % 100 != 0)
-			return 0;
-	}
+	if (e4b->bd_info->bb_check_counter++ % 10)
+		return 0;
 
 	while (order > 1) {
 		buddy = mb_find_buddy(e4b, order, &max);
-- 
1.8.3.1