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,USER_AGENT_SANE_1 autolearn=ham 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 746CFC3F2CD for ; Tue, 3 Mar 2020 14:06:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3AC782073D for ; Tue, 3 Mar 2020 14:06:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="dbmNbOqb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729422AbgCCOGd (ORCPT ); Tue, 3 Mar 2020 09:06:33 -0500 Received: from mail26.static.mailgun.info ([104.130.122.26]:24795 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728901AbgCCOGc (ORCPT ); Tue, 3 Mar 2020 09:06:32 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1583244392; h=In-Reply-To: Content-Type: MIME-Version: References: Message-ID: Subject: Cc: To: From: Date: Sender; bh=F8RBcxUmZe2rqyQIpBMVD6tFlkNTS1F7x44l6S2dx0k=; b=dbmNbOqboe74L7U9XnOcTIgxTo51W2eunAkSpFzkGhoKuKZpwph5FU9XIcid1+746OkfsaPU fmP8XjGDRFLbt2Mi7vPs3/d5UY2yEkeffmwah1mWZSKn/zqVWqngMviLPHWK9cjm05RNZaVl J6VLB/ZKCvlgws3AUgt1byPQ5AQ= X-Mailgun-Sending-Ip: 104.130.122.26 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5e5e645e.7f1eea896ab0-smtp-out-n03; Tue, 03 Mar 2020 14:06:22 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 888E8C4479C; Tue, 3 Mar 2020 14:06:22 +0000 (UTC) Received: from codeaurora.org (blr-c-bdr-fw-01_GlobalNAT_AllZones-Outside.qualcomm.com [103.229.19.19]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: stummala) by smtp.codeaurora.org (Postfix) with ESMTPSA id 35924C43383; Tue, 3 Mar 2020 14:06:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 35924C43383 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=stummala@codeaurora.org Date: Tue, 3 Mar 2020 19:36:16 +0530 From: Sahitya Tummala To: Chao Yu Cc: Jaegeuk Kim , linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] f2fs: Fix mount failure due to SPO after a successful online resize FS Message-ID: <20200303140616.GF20234@codeaurora.org> References: <1582799978-22277-1-git-send-email-stummala@codeaurora.org> <20200302043948.GE20234@codeaurora.org> <4d228adb-7038-1c03-e877-93221b920104@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4d228adb-7038-1c03-e877-93221b920104@huawei.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Chao, On Tue, Mar 03, 2020 at 08:06:21PM +0800, Chao Yu wrote: > Hi Sahitya, > > On 2020/3/2 12:39, Sahitya Tummala wrote: > > Hi Chao, > > > > On Fri, Feb 28, 2020 at 04:35:37PM +0800, Chao Yu wrote: > >> Hi Sahitya, > >> > >> Good catch. > >> > >> On 2020/2/27 18:39, Sahitya Tummala wrote: > >>> Even though online resize is successfully done, a SPO immediately > >>> after resize, still causes below error in the next mount. > >>> > >>> [ 11.294650] F2FS-fs (sda8): Wrong user_block_count: 2233856 > >>> [ 11.300272] F2FS-fs (sda8): Failed to get valid F2FS checkpoint > >>> > >>> This is because after FS metadata is updated in update_fs_metadata() > >>> if the SBI_IS_DIRTY is not dirty, then CP will not be done to reflect > >>> the new user_block_count. > >>> > >>> Signed-off-by: Sahitya Tummala > >>> --- > >>> fs/f2fs/gc.c | 1 + > >>> 1 file changed, 1 insertion(+) > >>> > >>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > >>> index a92fa49..a14a75f 100644 > >>> --- a/fs/f2fs/gc.c > >>> +++ b/fs/f2fs/gc.c > >>> @@ -1577,6 +1577,7 @@ int f2fs_resize_fs(struct f2fs_sb_info *sbi, __u64 block_count) > >>> > >>> update_fs_metadata(sbi, -secs); > >>> clear_sbi_flag(sbi, SBI_IS_RESIZEFS); > >> > >> Need a barrier here to keep order in between above code and set_sbi_flag(DIRTY)? > > > > I don't think a barrier will help here. Let us say there is a another context > > doing CP already, then it races with update_fs_metadata(), so it may or may not > > see the resize updates and it will also clear the SBI_IS_DIRTY flag set by resize > > (even with a barrier). > > I agreed, actually, we didn't consider race condition in between CP and > update_fs_metadata(), it should be fixed. > > > > > I think we need to synchronize this with CP context, so that these resize changes > > will be reflected properly. Please see the new diff below and help with the review. > > > > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > > index a14a75f..5554af8 100644 > > --- a/fs/f2fs/gc.c > > +++ b/fs/f2fs/gc.c > > @@ -1467,6 +1467,7 @@ static void update_fs_metadata(struct f2fs_sb_info *sbi, int secs) > > long long user_block_count = > > le64_to_cpu(F2FS_CKPT(sbi)->user_block_count); > > > > + clear_sbi_flag(sbi, SBI_IS_DIRTY); > > Why clear dirty flag here? Yes, it is not required. I will remove it. > > And why not use cp_mutex to protect update_fs_metadata() in error path of > f2fs_sync_fs() below? Yes, will add a lock there too. Thanks, > > > SM_I(sbi)->segment_count = (int)SM_I(sbi)->segment_count + segs; > > MAIN_SEGS(sbi) = (int)MAIN_SEGS(sbi) + segs; > > FREE_I(sbi)->free_sections = (int)FREE_I(sbi)->free_sections + secs; > > @@ -1575,9 +1576,12 @@ int f2fs_resize_fs(struct f2fs_sb_info *sbi, __u64 block_count) > > goto out; > > } > > > > + mutex_lock(&sbi->cp_mutex); > > update_fs_metadata(sbi, -secs); > > clear_sbi_flag(sbi, SBI_IS_RESIZEFS); > > set_sbi_flag(sbi, SBI_IS_DIRTY); > > + mutex_unlock(&sbi->cp_mutex); > > + > > err = f2fs_sync_fs(sbi->sb, 1); > > if (err) { > > update_fs_metadata(sbi, secs); > > ^^^^^^^^^^^^^^ > > In addition, I found that we missed to use sb_lock to protect f2fs_super_block > fields update, will submit a patch for that. > > Thanks, > > > > > thanks, > > > >> > >>> + set_sbi_flag(sbi, SBI_IS_DIRTY); > >>> err = f2fs_sync_fs(sbi->sb, 1); > >>> if (err) { > >>> update_fs_metadata(sbi, secs); > >> > >> Do we need to add clear_sbi_flag(, SBI_IS_DIRTY) into update_fs_metadata(), so above > >> path can be covered as well? > >> > >> Thanks, > >> > >>> > > -- -- Sent by a consultant of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.