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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 D41A2C433ED for ; Tue, 27 Apr 2021 14:25:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7272601FC for ; Tue, 27 Apr 2021 14:25:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236365AbhD0O0Y (ORCPT ); Tue, 27 Apr 2021 10:26:24 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:38041 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236358AbhD0O0V (ORCPT ); Tue, 27 Apr 2021 10:26:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619533537; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VV1vs7m19WfPvDHvy3Gut/vp9pL2IlMno2ml4UlBI+c=; b=fKzVJ+Zff/IfULlLsQg99JMswAFkPeKliWMSa8D4657VQK0MqTDiDXACuSusQh0hWAhayR yVXz6EvHWGQS/wr0eBMVmX1VfcKffavwVVk+8WqNeig8Zf99bfNPUtZSClpf7K2DGghMrj pftIoqCmUeZlm/Q9wZw3kPuE0P4CVew= Received: from mail-qv1-f70.google.com (mail-qv1-f70.google.com [209.85.219.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-53-oq10KsTvPM-udhN_Ixilug-1; Tue, 27 Apr 2021 10:25:34 -0400 X-MC-Unique: oq10KsTvPM-udhN_Ixilug-1 Received: by mail-qv1-f70.google.com with SMTP id x15-20020a0ce0cf0000b029019cb3e75c62so26000477qvk.15 for ; Tue, 27 Apr 2021 07:25:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=VV1vs7m19WfPvDHvy3Gut/vp9pL2IlMno2ml4UlBI+c=; b=a1yj5VLURl1+WHO4AN3+Ucn+cqfiA0bT9md5vy0nbYmU0vfHS6I/1w+9++JkG+lafK RSo2pyH4S77ST96gDqE8VfNx5WzFurC6yY02BlgJ5Zm0QiDuTIRYz0T6cFJwHCgGOj21 5FdRif0blhdfN2idv6BlE14mUajg90O9YUr2dkq9eH/XCDlK0Wen0n5fUZUmQquH/1DH 9GiGqr7y40Yy5OeAwo/YhREgsoZJix4Dt3kcydXugcvyo5gETyJoywS6Wr2rGZ+tf86V jlvm6tqp0bmbcbwvjnK+nqAllOYalOB27HIvyoalxpVQEMxO327dfw845yTEbSINHbgN vMKA== X-Gm-Message-State: AOAM533FfRRkqW4fHU5/UinLKMkgmYG0ahfHU4eWsy3Z/8VcICT4pc4p +mDovxiP80KHSNz/MM1zlvZTzsjvg2IJykyAwDJuLcbf14VXFV3gl4366RSnGblXsutoqF/VhxW o1Qyy79IFor/aAoEOOagv X-Received: by 2002:ac8:470e:: with SMTP id f14mr22091567qtp.54.1619533534254; Tue, 27 Apr 2021 07:25:34 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzokPEczqMiAwkJKmSH1B6JswSwmExeMatbYDCbNW3s7WGAH6TdIGDE5Z21uunqQyPtF88p6Q== X-Received: by 2002:ac8:470e:: with SMTP id f14mr22091546qtp.54.1619533533991; Tue, 27 Apr 2021 07:25:33 -0700 (PDT) Received: from bfoster ([98.216.211.229]) by smtp.gmail.com with ESMTPSA id l16sm2958905qkg.91.2021.04.27.07.25.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Apr 2021 07:25:33 -0700 (PDT) Date: Tue, 27 Apr 2021 10:25:31 -0400 From: Brian Foster To: Gao Xiang Cc: linux-xfs@vger.kernel.org, "Darrick J. Wong" , Dave Chinner , Zorro Lang Subject: Re: [PATCH] xfs: update superblock counters correctly for !lazysbcount Message-ID: References: <20210427011201.4175506-1-hsiangkao@redhat.com> <20210427131318.GA103178@xiangao.remote.csb> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210427131318.GA103178@xiangao.remote.csb> Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Apr 27, 2021 at 09:13:18PM +0800, Gao Xiang wrote: > On Tue, Apr 27, 2021 at 08:46:25AM -0400, Brian Foster wrote: > > On Tue, Apr 27, 2021 at 09:12:01AM +0800, Gao Xiang wrote: > > > From: Dave Chinner > > > > > > Keep the mount superblock counters up to date for !lazysbcount > > > filesystems so that when we log the superblock they do not need > > > updating in any way because they are already correct. > > > > > > It's found by what Zorro reported: > > > 1. mkfs.xfs -f -l lazy-count=0 -m crc=0 $dev > > > 2. mount $dev $mnt > > > 3. fsstress -d $mnt -p 100 -n 1000 (maybe need more or less io load) > > > 4. umount $mnt > > > 5. xfs_repair -n $dev > > > and I've seen no problem with this patch. > > > > > > Signed-off-by: Dave Chinner > > > Reported-by: Zorro Lang > > > Reviewed-by: Gao Xiang > > > Signed-off-by: Gao Xiang > > > --- > > > > Could you provide a bit more detail on the problem in the commit log? > > From the description and code change, it seems like there is some > > problem with doing the percpu aggregation in xfs_log_sb() on > > !lazysbcount filesystems. Therefore this patch reserves that behavior > > for lazysbcount, and instead enables per-transaction updates in the > > !lazysbcount specific cleanup path. Am I following that correctly? > > This patch inherited from Dave's patch [1] (and I added reproduable > steps), > https://lore.kernel.org/r/20210422014446.GZ63242@dread.disaster.area > > More details see my original patch v2: > https://lore.kernel.org/r/20210420110855.2961626-1-hsiangkao@redhat.com > Ok, thanks. So the bit about xfs_log_sb() is to avoid an incorrect overwrite of the in-core sb counters from the percpu counters on !lazysbcount. The xfs_trans_apply_sb_deltas() function already applies the transaction deltas to the on-disk superblock buffer, so the change to xfs_trans_unreserve_and_mod_sb() is basically to apply those same deltas to the in-core superblock so they are consistent in the !lazysbcount case... yes? If I'm following that correctly, this looks good to me: Reviewed-by: Brian Foster > Thanks, > Gao Xiang > > > > > Brian > > > > > > > > As per discussion earilier [1], use the way Dave suggested instead. > > > Also update the line to > > > mp->m_sb.sb_fdblocks += tp->t_fdblocks_delta + tp->t_res_fdblocks_delta; > > > so it can fix the case above. > > > > > > with XFS debug off, xfstests auto testcases fail on my loop-device-based > > > testbed with this patch and Darrick's [2]: > > > > > > generic/095 generic/300 generic/600 generic/607 xfs/073 xfs/148 xfs/273 > > > xfs/293 xfs/491 xfs/492 xfs/495 xfs/503 xfs/505 xfs/506 xfs/514 xfs/515 > > > > > > MKFS_OPTIONS="-mcrc=0 -llazy-count=0" > > > > > > and these testcases above still fail without these patches or with > > > XFS debug on, so I've seen no regression due to this patch. > > > > > > [1] https://lore.kernel.org/r/20210422030102.GA63242@dread.disaster.area/ > > > [2] https://lore.kernel.org/r/20210425154634.GZ3122264@magnolia/ > > > > > > fs/xfs/libxfs/xfs_sb.c | 16 +++++++++++++--- > > > fs/xfs/xfs_trans.c | 3 +++ > > > 2 files changed, 16 insertions(+), 3 deletions(-) > > > > > > diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c > > > index 60e6d255e5e2..dfbbcbd448c1 100644 > > > --- a/fs/xfs/libxfs/xfs_sb.c > > > +++ b/fs/xfs/libxfs/xfs_sb.c > > > @@ -926,9 +926,19 @@ xfs_log_sb( > > > struct xfs_mount *mp = tp->t_mountp; > > > struct xfs_buf *bp = xfs_trans_getsb(tp); > > > > > > - mp->m_sb.sb_icount = percpu_counter_sum(&mp->m_icount); > > > - mp->m_sb.sb_ifree = percpu_counter_sum(&mp->m_ifree); > > > - mp->m_sb.sb_fdblocks = percpu_counter_sum(&mp->m_fdblocks); > > > + /* > > > + * Lazy sb counters don't update the in-core superblock so do that now. > > > + * If this is at unmount, the counters will be exactly correct, but at > > > + * any other time they will only be ballpark correct because of > > > + * reservations that have been taken out percpu counters. If we have an > > > + * unclean shutdown, this will be corrected by log recovery rebuilding > > > + * the counters from the AGF block counts. > > > + */ > > > + if (xfs_sb_version_haslazysbcount(&mp->m_sb)) { > > > + mp->m_sb.sb_icount = percpu_counter_sum(&mp->m_icount); > > > + mp->m_sb.sb_ifree = percpu_counter_sum(&mp->m_ifree); > > > + mp->m_sb.sb_fdblocks = percpu_counter_sum(&mp->m_fdblocks); > > > + } > > > > > > xfs_sb_to_disk(bp->b_addr, &mp->m_sb); > > > xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF); > > > diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c > > > index bcc978011869..1e37aa8eca5a 100644 > > > --- a/fs/xfs/xfs_trans.c > > > +++ b/fs/xfs/xfs_trans.c > > > @@ -629,6 +629,9 @@ xfs_trans_unreserve_and_mod_sb( > > > > > > /* apply remaining deltas */ > > > spin_lock(&mp->m_sb_lock); > > > + mp->m_sb.sb_fdblocks += tp->t_fdblocks_delta + tp->t_res_fdblocks_delta; > > > + mp->m_sb.sb_icount += idelta; > > > + mp->m_sb.sb_ifree += ifreedelta; > > > mp->m_sb.sb_frextents += rtxdelta; > > > mp->m_sb.sb_dblocks += tp->t_dblocks_delta; > > > mp->m_sb.sb_agcount += tp->t_agcount_delta; > > > -- > > > 2.27.0 > > > > > >