linux-ext4 - [PATCH 2/2] ext4: use optimized mballoc scanning regardless of inode format

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Message-ID: <20260114182836.14120-4-jack@suse.cz>
Date: Wed, 14 Jan 2026 19:28:19 +0100
From: Jan Kara <jack@...e.cz>
To: Ted Tso <tytso@....edu>
Cc: <linux-ext4@...r.kernel.org>,
	Baokun Li <libaokun1@...wei.com>,
	Pedro Falcato <pfalcato@...e.de>,
	Jan Kara <jack@...e.cz>,
	Zhang Yi <yi.zhang@...wei.com>
Subject: [PATCH 2/2] ext4: use optimized mballoc scanning regardless of inode format

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@...wei.com>
Reviewed-by: Zhang Yi <yi.zhang@...wei.com>
Signed-off-by: Jan Kara <jack@...e.cz>
---
 fs/ext4/mballoc.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a88fbaa4f5f4..bca62cc2be1c 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1148,8 +1148,6 @@ static inline int should_optimize_scan(struct ext4_allocation_context *ac)
 		return 0;
 	if (ac->ac_criteria >= CR_GOAL_LEN_SLOW)
 		return 0;
-	if (!ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS))
-		return 0;
 	return 1;
 }

-- 
2.51.0