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=-17.3 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, 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 57086C2BB48 for ; Mon, 14 Dec 2020 15:53:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2163B2251D for ; Mon, 14 Dec 2020 15:53:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729628AbgLNPxS (ORCPT ); Mon, 14 Dec 2020 10:53:18 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:37262 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729704AbgLNPxJ (ORCPT ); Mon, 14 Dec 2020 10:53:09 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607961103; 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=FsO2x/GY53EIHToPBwftYAHKZYVK/jtXYf+Hn5qasZU=; b=CdfLPQEEWRJf5AU2bhEbO/Bna2Tc4vKrstZ1hjGgJzUa7UtP1W4eXNTMn6fgwC/C99ajwO bXj1tehtcFi7VYQAlUu6tZW3vCLmoRSd5MsYCJuW9U5UYPBvMtDoa3DpFrW1K14gSLXYOG G6OYXJxRIwpuuGwhEQeXFT/bFQWuFtU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-289-8VMt_lveObmHvZDSabLszA-1; Mon, 14 Dec 2020 10:51:41 -0500 X-MC-Unique: 8VMt_lveObmHvZDSabLszA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 706386D521 for ; Mon, 14 Dec 2020 15:51:40 +0000 (UTC) Received: from localhost (unknown [10.66.61.36]) by smtp.corp.redhat.com (Postfix) with ESMTP id DEBDE10016FE; Mon, 14 Dec 2020 15:51:39 +0000 (UTC) Date: Tue, 15 Dec 2020 00:07:01 +0800 From: Zorro Lang To: Brian Foster Cc: fstests@vger.kernel.org Subject: Re: [PATCH] generic/563: use a loop device to avoid partition incompatibility Message-ID: <20201214160701.GA14354@localhost.localdomain> Mail-Followup-To: Brian Foster , fstests@vger.kernel.org References: <20201210161426.1927144-1-bfoster@redhat.com> <20201211084508.GY14354@localhost.localdomain> <20201211152140.GD2032335@bfoster> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201211152140.GD2032335@bfoster> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: fstests@vger.kernel.org On Fri, Dec 11, 2020 at 10:21:40AM -0500, Brian Foster wrote: > On Fri, Dec 11, 2020 at 04:45:08PM +0800, Zorro Lang wrote: > > On Thu, Dec 10, 2020 at 11:14:26AM -0500, Brian Foster wrote: > > > cgroup writeback accounting does not track partition level > > > statistics. Instead, I/O is accounted against the parent device. As > > > a result, the test fails if the scratch device happens to be a > > > device partition. Since parent level stats are potentially polluted > > > by factors external to the test, wrap the scratch device in a > > > loopback device to guarantee the test always runs on a top-level > > > block device. > > > > > > Reported-by: Boyang Xue > > > Signed-off-by: Brian Foster > > > --- > > > tests/generic/563 | 21 ++++++++++++++------- > > > 1 file changed, 14 insertions(+), 7 deletions(-) > > > > > > diff --git a/tests/generic/563 b/tests/generic/563 > > > index 51deaa2f..9292dece 100755 > > > --- a/tests/generic/563 > > > +++ b/tests/generic/563 > > > @@ -2,7 +2,7 @@ > > > # SPDX-License-Identifier: GPL-2.0 > > > # Copyright (c) 2019 Red Hat, Inc. All Rights Reserved. > > > # > > > -# FS QA Test No. 011 > > > +# FS QA Test No. 563 > > > # > > > # This test verifies that cgroup aware writeback properly accounts I/Os in > > > # various scenarios. We perform reads/writes from different combinations of > > > @@ -26,6 +26,8 @@ _cleanup() > > > > > > echo $$ > $cgdir/cgroup.procs > > > rmdir $cgdir/$seq-cg* > /dev/null 2>&1 > > > + umount $SCRATCH_MNT > /dev/null 2>&1 > > > + _destroy_loop_device $LOOP_DEV > /dev/null 2>&1 > > > } > > > > > > # get standard environment, filters and checks > > > @@ -42,14 +44,12 @@ rm -f $seqres.full > > > _supported_fs generic > > > _require_scratch > > > _require_cgroup2 io > > > +_require_loop > > > > > > # cgroup v2 writeback is only support on block devices so far > > > _require_block_device $SCRATCH_DEV > > > > > > -smajor=$((0x`stat -L -c %t $SCRATCH_DEV`)) > > > -sminor=$((0x`stat -L -c %T $SCRATCH_DEV`)) > > > cgdir=$CGROUP2_PATH > > > - > > > iosize=$((1024 * 1024 * 8)) > > > > > > # Check cgroup read/write charges against expected values. Allow for some > > > @@ -89,12 +89,19 @@ reset() > > > rmdir $cgdir/$seq-cg* > /dev/null 2>&1 > > > $XFS_IO_PROG -fc "pwrite 0 $iosize" $SCRATCH_MNT/file \ > > > >> $seqres.full 2>&1 > > > - _scratch_cycle_mount || _fail "mount failed" > > > + umount $SCRATCH_MNT || _fail "umount failed" > > > + _mount $LOOP_DEV $SCRATCH_MNT || _fail "mount failed" > > > stat $SCRATCH_MNT/file > /dev/null > > > } > > > > > > -_scratch_mkfs >> $seqres.full 2>&1 > > > -_scratch_mount > > > +# cgroup I/O accounting doesn't work on partitions. Use a loop device to rule > > > +# that out. > > > +LOOP_DEV=$(_create_loop_device $SCRATCH_DEV) > > > > I recommend using a file to create loop device. If you'd like to use SCRATCH_DEV > > to create loop device directly, you'd better to change the "_require_scratch" > > to "_require_scratch_nocheck". Or I think it might be failed, e.g. if SCRATCH_DEV > > is a 4k sector size device. > > > > What's the error that occurs with a 4k device, out of curiosity? I > suppose if it's just a repair thing then using _nocheck probably makes > sense (or technically might make sense regardless since we're not > formatting the scratch device directly). I don't mind creating a file > and using loop on that, but would like to make sure I understand if/why > it's necessary. The XFS on underlying device will cause fsck fail, likes this: # modprobe scsi_debug sector_size=4096 physblk_exp=0 dev_size_mb=1024 # losetup -f --show /dev/sdc /dev/loop0 # # mkfs.xfs -f /dev/loop0 meta-data=/dev/loop0 isize=512 agcount=4, agsize=65536 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=1, sparse=1, rmapbt=0 = reflink=1 data = bsize=4096 blocks=262144, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0, ftype=1 log =internal log bsize=4096 blocks=2560, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 Discarding blocks...Done. # xfs_repair -n /dev/loop0 [passed] # losetup -d /dev/loop0 # xfs_repair -n /dev/sdc Phase 1 - find and verify superblock... xfs_repair: read failed: Invalid argument xfs_repair: data size check failed xfs_repair: cannot repair this filesystem. Sorry. The xfstests always do fsck on SCRATCH_DEV except you use _require_scratch_nocheck at the beginning of a sub-case, to skip the fsck. Thanks, Zorro > > > Others look good to me. > > > > Thanks for the feedback. > > Brian > > > Thanks, > > Zorro > > > > > +smajor=$((0x`stat -L -c %t $LOOP_DEV`)) > > > +sminor=$((0x`stat -L -c %T $LOOP_DEV`)) > > > + > > > +_mkfs_dev $LOOP_DEV >> $seqres.full 2>&1 > > > +_mount $LOOP_DEV $SCRATCH_MNT || _fail "mount failed" > > > > > > echo "+io" > $cgdir/cgroup.subtree_control || _fail "subtree control" > > > > > > -- > > > 2.26.2 > > > > > >