[PATCH 6.1 172/232] ext4: use optimized mballoc scanning regardless of inode format

Sasha Levin
2026-02-28T18:13:55Z

From: Jan Kara <jack@suse.cz>

commit 3574c322b1d0eb32dbd76b469cb08f9a67641599 upstream.

Currently we don't used mballoc optimized scanning (using max free
extent order and avg free extent order group lists) for inodes with
indirect block based format. This is confusing for users and I don't see
a good reason for that. Even with indirect block based inode format we
can spend big amount of time searching for free blocks for large
filesystems with fragmented free space. To add to the confusion before
commit 077d0c2c78df ("ext4: make mb_optimize_scan performance mount
option work with extents") optimized scanning was applied *only* to
indirect block based inodes so that commit appears as a performance
regression to some users. Just use optimized scanning whenever it is
enabled by mount options.

Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Link: https://patch.msgid.link/20260114182836.14120-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ext4/mballoc.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index da0c63897190b..71e15007ffdf4 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -974,8 +974,6 @@ static inline int should_optimize_scan(struct ext4_allocation_context *ac)
return 0;
if (ac->ac_criteria >= 2)
return 0;
- if (!ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS))
- return 0;
return 1;
}

--
2.51.0