From mboxrd@z Thu Jan 1 00:00:00 1970 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 0EC4EC433F5 for ; Mon, 14 Feb 2022 23:27:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232127AbiBNX13 (ORCPT ); Mon, 14 Feb 2022 18:27:29 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:50092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229449AbiBNX12 (ORCPT ); Mon, 14 Feb 2022 18:27:28 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9222DE02E8 for ; Mon, 14 Feb 2022 15:27:19 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3F0C2B80DCF for ; Mon, 14 Feb 2022 23:27:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA8FEC340E9; Mon, 14 Feb 2022 23:27:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1644881236; bh=1rUwvY875LcPgPbddOenVKZ0pqUKLLYVQWdprK8vuL4=; h=Date:From:To:Subject:References:In-Reply-To:From; b=sg5q9SmFqYCq11rnUvanZEhYF70xWXNghcej86iEvOPdn/vYIFSdX+F6od7INs+Gq 8yCRumER+hZcvhojrZdS4vcXR3dY5YpuK92+RCfHXcC2XtqAToa9lg67NjItD+Bbh4 ZZ6FeRyXnVykXry3LI0jGIo4j1vw35m5888XL11OicovXysXJUyqkYttapcRRKQZ2B GNaW3VI0NCQmoPYvQArKiJ7GZbbpHi0i/tFJFnI03PEYDjfO37Uw/AwBNtfNcYNjuw /oHTirlYJ+lLOxohfuZYSpjds1bRqH6oYxHDHglCz7sESUEMCtTDYwBEubm28X4nUT fFRE7svXBU6Dw== Date: Mon, 14 Feb 2022 15:27:15 -0800 From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [PATCH 2/2 v2] f2fs: avoid an infinite loop in f2fs_sync_dirty_inodes Message-ID: References: <20220212142023.2508247-1-jaegeuk@kernel.org> <20220212142023.2508247-2-jaegeuk@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220212142023.2508247-2-jaegeuk@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If one read IO is always failing, we can fall into an infinite loop in f2fs_sync_dirty_inodes. This happens during xfstests/generic/475. [ 142.803335] Buffer I/O error on dev dm-1, logical block 8388592, async page read ... [ 382.887210] submit_bio_noacct+0xdd/0x2a0 [ 382.887213] submit_bio+0x80/0x110 [ 382.887223] __submit_bio+0x4d/0x300 [f2fs] [ 382.887282] f2fs_submit_page_bio+0x125/0x200 [f2fs] [ 382.887299] __get_meta_page+0xc9/0x280 [f2fs] [ 382.887315] f2fs_get_meta_page+0x13/0x20 [f2fs] [ 382.887331] f2fs_get_node_info+0x317/0x3c0 [f2fs] [ 382.887350] f2fs_do_write_data_page+0x327/0x6f0 [f2fs] [ 382.887367] f2fs_write_single_data_page+0x5b7/0x960 [f2fs] [ 382.887386] f2fs_write_cache_pages+0x302/0x890 [f2fs] [ 382.887405] ? preempt_count_add+0x7a/0xc0 [ 382.887408] f2fs_write_data_pages+0xfd/0x320 [f2fs] [ 382.887425] ? _raw_spin_unlock+0x1a/0x30 [ 382.887428] do_writepages+0xd3/0x1d0 [ 382.887432] filemap_fdatawrite_wbc+0x69/0x90 [ 382.887434] filemap_fdatawrite+0x50/0x70 [ 382.887437] f2fs_sync_dirty_inodes+0xa4/0x270 [f2fs] [ 382.887453] f2fs_write_checkpoint+0x189/0x1640 [f2fs] [ 382.887469] ? schedule_timeout+0x114/0x150 [ 382.887471] ? ttwu_do_activate+0x6d/0xb0 [ 382.887473] ? preempt_count_add+0x7a/0xc0 [ 382.887476] kill_f2fs_super+0xca/0x100 [f2fs] [ 382.887491] deactivate_locked_super+0x35/0xa0 [ 382.887494] deactivate_super+0x40/0x50 [ 382.887497] cleanup_mnt+0x139/0x190 [ 382.887499] __cleanup_mnt+0x12/0x20 [ 382.887501] task_work_run+0x64/0xa0 [ 382.887505] exit_to_user_mode_prepare+0x1b7/0x1c0 [ 382.887508] syscall_exit_to_user_mode+0x27/0x50 [ 382.887510] do_syscall_64+0x48/0xc0 [ 382.887513] entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: Jaegeuk Kim --- Change log from v1: - fix a regression to report EIO too early fs/f2fs/checkpoint.c | 13 ++++++++----- fs/f2fs/f2fs.h | 3 +++ 2 files changed, 11 insertions(+), 5 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 203a1577942d..56c81c68ef71 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -1059,13 +1059,13 @@ int f2fs_sync_dirty_inodes(struct f2fs_sb_info *sbi, enum inode_type type) struct inode *inode; struct f2fs_inode_info *fi; bool is_dir = (type == DIR_INODE); - unsigned long ino = 0; + unsigned long ino = 0, retry_count = DEFAULT_RETRY_SYNC_DIR_COUNT; trace_f2fs_sync_dirty_inodes_enter(sbi->sb, is_dir, get_pages(sbi, is_dir ? F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA)); retry: - if (unlikely(f2fs_cp_error(sbi))) { + if (unlikely(f2fs_cp_error(sbi) || (is_dir && !retry_count))) { trace_f2fs_sync_dirty_inodes_exit(sbi->sb, is_dir, get_pages(sbi, is_dir ? F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA)); @@ -1096,10 +1096,13 @@ int f2fs_sync_dirty_inodes(struct f2fs_sb_info *sbi, enum inode_type type) iput(inode); /* We need to give cpu to another writers. */ - if (ino == cur_ino) - cond_resched(); - else + if (ino == cur_ino) { + retry_count--; + io_schedule_timeout(DEFAULT_IO_TIMEOUT); + } else { + retry_count = DEFAULT_RETRY_SYNC_DIR_COUNT; ino = cur_ino; + } } else { /* * We should submit bio, since it exists several diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index c9515c3c54fd..f40ef7b61965 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -577,6 +577,9 @@ enum { /* maximum retry quota flush count */ #define DEFAULT_RETRY_QUOTA_FLUSH_COUNT 8 +/* maximum retry sync dirty inodes */ +#define DEFAULT_RETRY_SYNC_DIR_COUNT 3000 + #define F2FS_LINK_MAX 0xffffffff /* maximum link count per file */ #define MAX_DIR_RA_PAGES 4 /* maximum ra pages of dir */ -- 2.35.1.265.g69c8d7142f-goog