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 371A2C433F5 for ; Fri, 11 Mar 2022 05:22:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346318AbiCKFXU (ORCPT ); Fri, 11 Mar 2022 00:23:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239861AbiCKFXS (ORCPT ); Fri, 11 Mar 2022 00:23:18 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 928571ACA36 for ; Thu, 10 Mar 2022 21:22:12 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 0450B61ABC for ; Fri, 11 Mar 2022 05:22:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C949C340EC; Fri, 11 Mar 2022 05:22:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646976131; bh=8gqE6SNCXYrxBQ43gUi43oisXrMLQipGnGqrX9t1jAg=; h=Date:From:To:Subject:References:In-Reply-To:From; b=inNNV5r+0gxtvwo+9FvyS2LZxm1WpUr72oCgH87pOCQpqcSm5wZehU93QOG2Zfa0o TxHFZSqxo5HIg38GU+5pjWilylKLLgx0lDCAETphdnVFPRYAfZbPIBDSlqOJ3RVcEC NoRYTSkqf9aXephGUXBWSobaX+Tx23pyvwk6VvmhuTmGkef5AsfryR42WGPDuRS6vt mRKvS0GjvRi8En4Bvx6SUKA6Rh3wQSKtPKTpIGwTIJW8uWrcaILEvAIrQJMphCDSXt q0YsxCWHZ+HpwC3blY+kA5dPFHVgljXol5kGQ1LfGAg3uMaFRTnEnA4eTpVRLngih0 FsBI6Q0smfrIw== Date: Thu, 10 Mar 2022 21:22:09 -0800 From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [PATCH 1/2 v2] f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs Message-ID: References: <20220309214834.3408741-1-jaegeuk@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220309214834.3408741-1-jaegeuk@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Let's purge inode cache in order to avoid the below deadlock. [freeze test] shrinkder freeze_super - pwercpu_down_write(SB_FREEZE_FS) - super_cache_scan - down_read(&sb->s_umount) - prune_icache_sb - dispose_list - evict - f2fs_evict_inode thaw_super - down_write(&sb->s_umount); - __percpu_down_read(SB_FREEZE_FS) Signed-off-by: Jaegeuk Kim --- Change log from v1: - add doc Documentation/ABI/testing/sysfs-fs-f2fs | 1 + fs/f2fs/debug.c | 1 + fs/f2fs/f2fs.h | 1 + fs/f2fs/inode.c | 6 ++++-- fs/f2fs/super.c | 4 ++++ 5 files changed, 11 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs index 58bf0dc83712..5a5f3c5445f6 100644 --- a/Documentation/ABI/testing/sysfs-fs-f2fs +++ b/Documentation/ABI/testing/sysfs-fs-f2fs @@ -458,6 +458,7 @@ Description: Show status of f2fs superblock in real time. 0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP 0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted 0x2000 SBI_IS_RESIZEFS resizefs is in process + 0x4000 SBI_IS_FREEZING freefs is in process ====== ===================== ================================= What: /sys/fs/f2fs//ckpt_thread_ioprio diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c index 9a13902c7702..cba5eab24595 100644 --- a/fs/f2fs/debug.c +++ b/fs/f2fs/debug.c @@ -338,6 +338,7 @@ static char *s_flag[] = { [SBI_QUOTA_SKIP_FLUSH] = " quota_skip_flush", [SBI_QUOTA_NEED_REPAIR] = " quota_need_repair", [SBI_IS_RESIZEFS] = " resizefs", + [SBI_IS_FREEZING] = " freezefs", }; static int stat_show(struct seq_file *s, void *v) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 68d791ec8b27..da729f53daa8 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1293,6 +1293,7 @@ enum { SBI_QUOTA_SKIP_FLUSH, /* skip flushing quota in current CP */ SBI_QUOTA_NEED_REPAIR, /* quota file may be corrupted */ SBI_IS_RESIZEFS, /* resizefs is in process */ + SBI_IS_FREEZING, /* freezefs is in process */ }; enum { diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index ab8e0c06c78c..71f232dcf3c2 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -778,7 +778,8 @@ void f2fs_evict_inode(struct inode *inode) f2fs_remove_ino_entry(sbi, inode->i_ino, UPDATE_INO); f2fs_remove_ino_entry(sbi, inode->i_ino, FLUSH_INO); - sb_start_intwrite(inode->i_sb); + if (!is_sbi_flag_set(sbi, SBI_IS_FREEZING)) + sb_start_intwrite(inode->i_sb); set_inode_flag(inode, FI_NO_ALLOC); i_size_write(inode, 0); retry: @@ -809,7 +810,8 @@ void f2fs_evict_inode(struct inode *inode) if (dquot_initialize_needed(inode)) set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR); } - sb_end_intwrite(inode->i_sb); + if (!is_sbi_flag_set(sbi, SBI_IS_FREEZING)) + sb_end_intwrite(inode->i_sb); no_delete: dquot_drop(inode); diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 8e3840973077..4b570b5c2674 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1663,11 +1663,15 @@ static int f2fs_freeze(struct super_block *sb) /* ensure no checkpoint required */ if (!llist_empty(&F2FS_SB(sb)->cprc_info.issue_list)) return -EINVAL; + + /* to avoid deadlock on f2fs_evict_inode->SB_FREEZE_FS */ + set_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING); return 0; } static int f2fs_unfreeze(struct super_block *sb) { + clear_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING); return 0; } -- 2.35.1.723.g4982287a31-goog