From nobody Wed Dec 17 00:15:54 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 237ADC7618E for ; Mon, 24 Apr 2023 03:39:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230413AbjDXDjs (ORCPT ); Sun, 23 Apr 2023 23:39:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35330 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230020AbjDXDjn (ORCPT ); Sun, 23 Apr 2023 23:39:43 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E87A2136; Sun, 23 Apr 2023 20:39:42 -0700 (PDT) Received: from dggpeml500021.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Q4W4R4LZTz17VvH; Mon, 24 Apr 2023 11:35:51 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500021.china.huawei.com (7.185.36.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Mon, 24 Apr 2023 11:39:40 +0800 From: Baokun Li To: CC: , , , , , , , , Subject: [PATCH v4 02/12] ext4: add a new helper to check if es must be kept Date: Mon, 24 Apr 2023 11:38:36 +0800 Message-ID: <20230424033846.4732-3-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230424033846.4732-1-libaokun1@huawei.com> References: <20230424033846.4732-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpeml500021.china.huawei.com (7.185.36.21) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In the extent status tree, we have extents which we can just drop without issues and extents we must not drop - this depends on the extent's status - currently ext4_es_is_delayed() extents must stay, others may be dropped. A helper function is added to help determine if the current extent can be dropped, although only ext4_es_is_delayed() extents cannot be dropped currently. Suggested-by: Jan Kara Signed-off-by: Baokun Li Reviewed-by: Jan Kara --- fs/ext4/extents_status.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c index 7bc221038c6c..573723b23d19 100644 --- a/fs/ext4/extents_status.c +++ b/fs/ext4/extents_status.c @@ -448,6 +448,19 @@ static void ext4_es_list_del(struct inode *inode) spin_unlock(&sbi->s_es_lock); } =20 +/* + * Returns true if we cannot fail to allocate memory for this extent_status + * entry and cannot reclaim it until its status changes. + */ +static inline bool ext4_es_must_keep(struct extent_status *es) +{ + /* fiemap, bigalloc, and seek_data/hole need to use it. */ + if (ext4_es_is_delayed(es)) + return true; + + return false; +} + static struct extent_status * ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t le= n, ext4_fsblk_t pblk) @@ -460,10 +473,8 @@ ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t = lblk, ext4_lblk_t len, es->es_len =3D len; es->es_pblk =3D pblk; =20 - /* - * We don't count delayed extent because we never try to reclaim them - */ - if (!ext4_es_is_delayed(es)) { + /* We never try to reclaim a must kept extent, so we don't count it. */ + if (!ext4_es_must_keep(es)) { if (!EXT4_I(inode)->i_es_shk_nr++) ext4_es_list_add(inode); percpu_counter_inc(&EXT4_SB(inode->i_sb)-> @@ -481,8 +492,8 @@ static void ext4_es_free_extent(struct inode *inode, st= ruct extent_status *es) EXT4_I(inode)->i_es_all_nr--; percpu_counter_dec(&EXT4_SB(inode->i_sb)->s_es_stats.es_stats_all_cnt); =20 - /* Decrease the shrink counter when this es is not delayed */ - if (!ext4_es_is_delayed(es)) { + /* Decrease the shrink counter when we can reclaim the extent. */ + if (!ext4_es_must_keep(es)) { BUG_ON(EXT4_I(inode)->i_es_shk_nr =3D=3D 0); if (!--EXT4_I(inode)->i_es_shk_nr) ext4_es_list_del(inode); @@ -853,7 +864,7 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lbl= k_t lblk, if (err =3D=3D -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb), 128, EXT4_I(inode))) goto retry; - if (err =3D=3D -ENOMEM && !ext4_es_is_delayed(&newes)) + if (err =3D=3D -ENOMEM && !ext4_es_must_keep(&newes)) err =3D 0; =20 if (sbi->s_cluster_ratio > 1 && test_opt(inode->i_sb, DELALLOC) && @@ -1706,11 +1717,8 @@ static int es_do_reclaim_extents(struct ext4_inode_i= nfo *ei, ext4_lblk_t end, =20 (*nr_to_scan)--; node =3D rb_next(&es->rb_node); - /* - * We can't reclaim delayed extent from status tree because - * fiemap, bigallic, and seek_data/hole need to use it. - */ - if (ext4_es_is_delayed(es)) + + if (ext4_es_must_keep(es)) goto next; if (ext4_es_is_referenced(es)) { ext4_es_clear_referenced(es); @@ -1774,7 +1782,7 @@ void ext4_clear_inode_es(struct inode *inode) while (node) { es =3D rb_entry(node, struct extent_status, rb_node); node =3D rb_next(node); - if (!ext4_es_is_delayed(es)) { + if (!ext4_es_must_keep(es)) { rb_erase(&es->rb_node, &tree->root); ext4_es_free_extent(inode, es); } --=20 2.31.1