From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AA98718B47C for ; Mon, 25 Nov 2024 11:13:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732533232; cv=none; b=B95cg/VX7lbyeLIHpaCHNi7ZW0V6bzARyEBMX6Q84Z236owxJuDNYivFsij/KGieQ0ecUU/wozuqAzFChXl8sK6HGB18YqmRnxza16ulW49BlrTJMiyLIyT8uJSJ3NbKfHAZpVJdpfgwf6TviUBy3592XtFEZh/NApSw/j5CaHM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732533232; c=relaxed/simple; bh=em2+R4u2wEQPpLl6eVmHSeE2ZgN4ooDYI6iFZ92Y+sI=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=k8SqM+SS3mQgFHuhMCgB2Afh2V5czKDhzkdLq++IHGSd7D+SlLJVRCxALiM9TQN0MeX8s5yXngppCe4xTvGMbq5icQGsdI5N7trE38Z6XK39Z8ENhDQe35cTVuBpQtZAcj/e+9O56Untcbt2R1IcM1CvqQM78wtK3GO1xseTEKg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FJPmdiQe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="FJPmdiQe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF722C4CECE; Mon, 25 Nov 2024 11:13:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1732533232; bh=em2+R4u2wEQPpLl6eVmHSeE2ZgN4ooDYI6iFZ92Y+sI=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=FJPmdiQekWqfdMgE1/OmJyFKt6+URYxapD+gGJI5GzAwba32anEEa4xmEB+xMYiC2 Ft1UT90zHjBBJhwlrBNDhxHdIfUrabWdhpXMjaQB1XUITtrdnA7D2quZlrxoG2naAU gtpk+BJNv97q+8Gj5MTbf+wiGuFZ6q7lcck45aQpbMTVJW7Yfy9aa3RewgNdpAqb1A sT3K6KT7Pxt/r+ieMZkP9FpPwKCfRBSWsWFK1e1BrO/5duCkkU+ICdKYpSh/7qr8G7 zOODtTV3aotqEcjUx5tuYQ/FUjhxdzFgGb4KukBcr09Thx4e9sEjJCRjuuAgoBbjgO koo9L7fp/OBGA== Message-ID: <0b9efdbb-e897-45d2-8005-bd3d6f6fa2db@kernel.org> Date: Mon, 25 Nov 2024 19:13:48 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: Chao Yu , "linux-f2fs-devel@lists.sourceforge.net" , "linux-kernel@vger.kernel.org" , =?UTF-8?B?54mb5b+X5Zu9IChaaGlndW8gTml1KQ==?= Subject: =?UTF-8?B?UmU6IOetlOWkjTogW1BBVENIIHYyIDEvMl0gZjJmczogZml4IHRvIHNo?= =?UTF-8?Q?rink_read_extent_node_in_batches?= To: =?UTF-8?B?546L56eA57qiIChYaXVob25nIFdhbmcp?= , "jaegeuk@kernel.org" References: <20241122065005.3772987-1-chao@kernel.org> <6ddf779148f44295acfbe547d9ec3aab@BJMBX02.spreadtrum.com> Content-Language: en-US From: Chao Yu In-Reply-To: <6ddf779148f44295acfbe547d9ec3aab@BJMBX02.spreadtrum.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2024/11/25 11:11, 王秀红 (Xiuhong Wang) wrote: > Hi Chao, > > after tested in this weekend with these patch base on the orginal case, no issue reproduced, so > Tested-by: Xiuhong Wang Hi Xiuhong, Thanks for helping to test. Thanks, > > thanks! > > -----邮件原件----- > 发件人: Chao Yu > 发送时间: 2024年11月22日 14:50 > 收件人: jaegeuk@kernel.org > 抄送: linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org; Chao Yu ; 王秀红 (Xiuhong Wang) ; 牛志国 (Zhiguo Niu) > 主题: [PATCH v2 1/2] f2fs: fix to shrink read extent node in batches > > > 注意: 这封邮件来自于外部。除非你确定邮件内容安全，否则不要点击任何链接和附件。 > CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. > > > > We use rwlock to protect core structure data of extent tree during its shrink, however, if there is a huge number of extent nodes in extent tree, during shrink of extent tree, it may hold rwlock for a very long time, which may trigger kernel hang issue. > > This patch fixes to shrink read extent node in batches, so that, critical region of the rwlock can be shrunk to avoid its extreme long time hold. > > Reported-by: Xiuhong Wang > Closes: https://lore.kernel.org/linux-f2fs-devel/20241112110627.1314632-1-xiuhong.wang@unisoc.com/ > Signed-off-by: Xiuhong Wang > Signed-off-by: Zhiguo Niu > Signed-off-by: Chao Yu > --- > v2: > - no updates. > fs/f2fs/extent_cache.c | 69 +++++++++++++++++++++++++----------------- > 1 file changed, 41 insertions(+), 28 deletions(-) > > diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c index 019c1f7b7fa5..b7a6817b44b0 100644 > --- a/fs/f2fs/extent_cache.c > +++ b/fs/f2fs/extent_cache.c > @@ -379,21 +379,22 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode, } > > static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi, > - struct extent_tree *et) > + struct extent_tree *et, unsigned int > + nr_shrink) > { > struct rb_node *node, *next; > struct extent_node *en; > - unsigned int count = atomic_read(&et->node_cnt); > + unsigned int count; > > node = rb_first_cached(&et->root); > - while (node) { > + > + for (count = 0; node && count < nr_shrink; count++) { > next = rb_next(node); > en = rb_entry(node, struct extent_node, rb_node); > __release_extent_node(sbi, et, en); > node = next; > } > > - return count - atomic_read(&et->node_cnt); > + return count; > } > > static void __drop_largest_extent(struct extent_tree *et, @@ -622,6 +623,30 @@ static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi, > return en; > } > > +static unsigned int __destroy_extent_node(struct inode *inode, > + enum extent_type type) { > + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > + struct extent_tree *et = F2FS_I(inode)->extent_tree[type]; > + unsigned int nr_shrink = type == EX_READ ? > + READ_EXTENT_CACHE_SHRINK_NUMBER : > + AGE_EXTENT_CACHE_SHRINK_NUMBER; > + unsigned int node_cnt = 0; > + > + if (!et || !atomic_read(&et->node_cnt)) > + return 0; > + > + while (atomic_read(&et->node_cnt)) { > + write_lock(&et->lock); > + node_cnt += __free_extent_tree(sbi, et, nr_shrink); > + write_unlock(&et->lock); > + } > + > + f2fs_bug_on(sbi, atomic_read(&et->node_cnt)); > + > + return node_cnt; > +} > + > static void __update_extent_tree_range(struct inode *inode, > struct extent_info *tei, enum extent_type type) { @@ -760,9 +785,6 @@ static void __update_extent_tree_range(struct inode *inode, > } > } > > - if (is_inode_flag_set(inode, FI_NO_EXTENT)) > - __free_extent_tree(sbi, et); > - > if (et->largest_updated) { > et->largest_updated = false; > updated = true; > @@ -780,6 +802,9 @@ static void __update_extent_tree_range(struct inode *inode, > out_read_extent_cache: > write_unlock(&et->lock); > > + if (is_inode_flag_set(inode, FI_NO_EXTENT)) > + __destroy_extent_node(inode, EX_READ); > + > if (updated) > f2fs_mark_inode_dirty_sync(inode, true); } @@ -942,10 +967,14 @@ static unsigned int __shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink > list_for_each_entry_safe(et, next, &eti->zombie_list, list) { > if (atomic_read(&et->node_cnt)) { > write_lock(&et->lock); > - node_cnt += __free_extent_tree(sbi, et); > + node_cnt += __free_extent_tree(sbi, et, > + nr_shrink - node_cnt - > + tree_cnt); > write_unlock(&et->lock); > } > - f2fs_bug_on(sbi, atomic_read(&et->node_cnt)); > + > + if (atomic_read(&et->node_cnt)) > + goto unlock_out; > + > list_del_init(&et->list); > radix_tree_delete(&eti->extent_tree_root, et->ino); > kmem_cache_free(extent_tree_slab, et); @@ -1084,23 +1113,6 @@ unsigned int f2fs_shrink_age_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink > return __shrink_extent_tree(sbi, nr_shrink, EX_BLOCK_AGE); } > > -static unsigned int __destroy_extent_node(struct inode *inode, > - enum extent_type type) > -{ > - struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > - struct extent_tree *et = F2FS_I(inode)->extent_tree[type]; > - unsigned int node_cnt = 0; > - > - if (!et || !atomic_read(&et->node_cnt)) > - return 0; > - > - write_lock(&et->lock); > - node_cnt = __free_extent_tree(sbi, et); > - write_unlock(&et->lock); > - > - return node_cnt; > -} > - > void f2fs_destroy_extent_node(struct inode *inode) { > __destroy_extent_node(inode, EX_READ); @@ -1109,7 +1121,6 @@ void f2fs_destroy_extent_node(struct inode *inode) > > static void __drop_extent_tree(struct inode *inode, enum extent_type type) { > - struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > struct extent_tree *et = F2FS_I(inode)->extent_tree[type]; > bool updated = false; > > @@ -1117,7 +1128,6 @@ static void __drop_extent_tree(struct inode *inode, enum extent_type type) > return; > > write_lock(&et->lock); > - __free_extent_tree(sbi, et); > if (type == EX_READ) { > set_inode_flag(inode, FI_NO_EXTENT); > if (et->largest.len) { > @@ -1126,6 +1136,9 @@ static void __drop_extent_tree(struct inode *inode, enum extent_type type) > } > } > write_unlock(&et->lock); > + > + __destroy_extent_node(inode, type); > + > if (updated) > f2fs_mark_inode_dirty_sync(inode, true); } > -- > 2.40.1 >