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 X-Spam-Level: X-Spam-Status: No, score=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CBBA8C83004 for ; Thu, 30 Apr 2020 01:12:03 +0000 (UTC) Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 90B342082E; Thu, 30 Apr 2020 01:12:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sourceforge.net header.i=@sourceforge.net header.b="gg7Fpb7H"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sf.net header.i=@sf.net header.b="mzSAvQ8n" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 90B342082E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-f2fs-devel-bounces@lists.sourceforge.net Received: from [127.0.0.1] (helo=sfs-ml-1.v29.lw.sourceforge.com) by sfs-ml-1.v29.lw.sourceforge.com with esmtp (Exim 4.90_1) (envelope-from ) id 1jTxk9-0007nT-Tv; Thu, 30 Apr 2020 01:12:01 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-1.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jTxk8-0007n6-KV for linux-f2fs-devel@lists.sourceforge.net; Thu, 30 Apr 2020 01:12:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:CC:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=hRVJIZ1kt9O+HHoRrxtFm2LZsBppIzxxdoss52JVem4=; b=gg7Fpb7H97jQL1LC+lih/la88S 8S3jFX2ufuyeR8ceMwEdemzw9dopf/SS/wbcjPYrvI8f41mAYCU3xRDyxIjh9HwwNv1+IfyPdd+78 2JNmrt+vFzPYKFeiKQDUqEH2z5x6Z6lZ6A1Bnm/SgSbPCZfX4xUnRZNevMBebDjkJ0Uo=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:MIME-Version:Date: Message-ID:From:References:CC:To:Subject:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=hRVJIZ1kt9O+HHoRrxtFm2LZsBppIzxxdoss52JVem4=; b=mzSAvQ8nqk0harSIfY1Dx9nnY2 GdijB0S4+85WA1LzHx8DW2IC+eY+IWcYD01twUNhysZELBq7osoknOLrFXbbGvxm7+1Rub93FwPUg 0VjdtUny9gdUTNF329ygSJdqyCLFsYEKgJtdVjjr8762BqYLOZn8Z0anu5WIy5UfcGEE=; Received: from szxga06-in.huawei.com ([45.249.212.32] helo=huawei.com) by sfi-mx-4.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.2) id 1jTxk5-002pya-M1 for linux-f2fs-devel@lists.sourceforge.net; Thu, 30 Apr 2020 01:11:59 +0000 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 4C278CF36F6CE4FD2A34; Thu, 30 Apr 2020 09:11:48 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.204) with Microsoft SMTP Server (TLS) id 14.3.487.0; Thu, 30 Apr 2020 09:11:45 +0800 To: Sayali Lokhande , , References: <1588179630-22819-1-git-send-email-sayalil@codeaurora.org> From: Chao Yu Message-ID: <7c68cd6d-d858-f80c-f258-e5e1340b9aa3@huawei.com> Date: Thu, 30 Apr 2020 09:11:43 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1588179630-22819-1-git-send-email-sayalil@codeaurora.org> Content-Language: en-US X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected X-Headers-End: 1jTxk5-002pya-M1 Subject: Re: [f2fs-dev] [PATCH V3] f2fs: Avoid double lock for cp_rwsem during checkpoint X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On 2020/4/30 1:00, Sayali Lokhande wrote: > There could be a scenario where f2fs_sync_node_pages gets > called during checkpoint, which in turn tries to flush > inline data and calls iput(). This results in deadlock as > iput() tries to hold cp_rwsem, which is already held at the > beginning by checkpoint->block_operations(). > > Call stack : > > Thread A Thread B > f2fs_write_checkpoint() > - block_operations(sbi) > - f2fs_lock_all(sbi); > - down_write(&sbi->cp_rwsem); > > - open() > - igrab() > - write() write inline data > - unlink() > - f2fs_sync_node_pages() > - if (is_inline_node(page)) > - flush_inline_data() > - ilookup() > page = f2fs_pagecache_get_page() > if (!page) > goto iput_out; > iput_out: > -close() > -iput() > iput(inode); > - f2fs_evict_inode() > - f2fs_truncate_blocks() > - f2fs_lock_op() > - down_read(&sbi->cp_rwsem); > > Fixes: 399368372ed9 ("f2fs: introduce a new global lock scheme") IMO, it should be 2049d4fcb057 ("f2fs: avoid multiple node page writes due to inline_data") It brings iput() to checkpoint process for the first time. Thanks, > Signed-off-by: Sayali Lokhande > --- > fs/f2fs/checkpoint.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c > index 5ba649e..97b6378 100644 > --- a/fs/f2fs/checkpoint.c > +++ b/fs/f2fs/checkpoint.c > @@ -1219,21 +1219,19 @@ static int block_operations(struct f2fs_sb_info *sbi) > goto retry_flush_quotas; > } > > -retry_flush_nodes: > down_write(&sbi->node_write); > > if (get_pages(sbi, F2FS_DIRTY_NODES)) { > up_write(&sbi->node_write); > + up_write(&sbi->node_change); > + f2fs_unlock_all(sbi); > atomic_inc(&sbi->wb_sync_req[NODE]); > err = f2fs_sync_node_pages(sbi, &wbc, false, FS_CP_NODE_IO); > atomic_dec(&sbi->wb_sync_req[NODE]); > - if (err) { > - up_write(&sbi->node_change); > - f2fs_unlock_all(sbi); > + if (err) > goto out; > - } > cond_resched(); > - goto retry_flush_nodes; > + goto retry_flush_quotas; > } > > /* > _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel