From:   Kemeng Shi <shikemeng@huaweicloud.com>
To:     tytso@mit.edu, adilger.kernel@dilger.ca, jack@suse.cz,
        ojaswin@linux.ibm.com, ritesh.list@gmail.com
Cc:     linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
        shikemeng@huaweicloud.com
Subject: [PATCH v2 18/20] ext4: remove repeat assignment to ac_f_ex
Date:   Tue, 28 Feb 2023 19:43:04 +0800
Message-Id: <20230228114306.3328235-19-shikemeng@huaweicloud.com>
In-Reply-To: <20230228114306.3328235-1-shikemeng@huaweicloud.com>
References: <20230228114306.3328235-1-shikemeng@huaweicloud.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Call trace to assign ac_f_ex:
ext4_mb_use_best_found
	ac->ac_f_ex = ac->ac_b_ex;
	ext4_mb_new_preallocation
		ext4_mb_new_group_pa
			ac->ac_f_ex = ac->ac_b_ex;
		ext4_mb_new_inode_pa
			ac->ac_f_ex = ac->ac_b_ex;

Actually allocated blocks is already stored in ac_f_ex in
ext4_mb_use_best_found, so there is no need to assign ac_f_ex
in ext4_mb_new_group_pa and ext4_mb_new_inode_pa.
Just remove repeat assignment to ac_f_ex in ext4_mb_new_group_pa
and ext4_mb_new_inode_pa.

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
---
 fs/ext4/mballoc.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index f7fa081bece9..8c5ad44f71f4 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4632,10 +4632,6 @@ ext4_mb_new_inode_pa(struct ext4_allocation_context *ac)
 		BUG_ON(ac->ac_o_ex.fe_len > ac->ac_b_ex.fe_len);
 	}
 
-	/* preallocation can change ac_b_ex, thus we store actually
-	 * allocated blocks for history */
-	ac->ac_f_ex = ac->ac_b_ex;
-
 	pa->pa_lstart = ac->ac_b_ex.fe_logical;
 	pa->pa_pstart = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
 	pa->pa_len = ac->ac_b_ex.fe_len;
@@ -4686,10 +4682,6 @@ ext4_mb_new_group_pa(struct ext4_allocation_context *ac)
 
 	pa = ac->ac_pa;
 
-	/* preallocation can change ac_b_ex, thus we store actually
-	 * allocated blocks for history */
-	ac->ac_f_ex = ac->ac_b_ex;
-
 	pa->pa_pstart = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
 	pa->pa_lstart = pa->pa_pstart;
 	pa->pa_len = ac->ac_b_ex.fe_len;
-- 
2.30.0