From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cn.fujitsu.com ([59.151.112.132]:15178 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S932797AbcFNCia (ORCPT ); Mon, 13 Jun 2016 22:38:30 -0400 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id A7DBA409257A for ; Tue, 14 Jun 2016 10:38:26 +0800 (CST) Subject: Re: [PATCH] fstests: ext4: regression test for fsync transaction ids initialization References: <1465354945-11307-1-git-send-email-wangxg.fnst@cn.fujitsu.com> <20160608085546.GP5140@eguan.usersys.redhat.com> From: Wang Xiaoguang Message-ID: <575F6DDC.9050000@cn.fujitsu.com> Date: Tue, 14 Jun 2016 10:37:16 +0800 MIME-Version: 1.0 In-Reply-To: <20160608085546.GP5140@eguan.usersys.redhat.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Sender: fstests-owner@vger.kernel.org To: fstests@vger.kernel.org List-ID: Hello, Thanks for reviewing. On 06/08/2016 04:55 PM, Eryu Guan wrote: > On Wed, Jun 08, 2016 at 11:02:25AM +0800, Wang Xiaoguang wrote: >> Commit 688f869 fixed this bug: >> ext4: ext4: Initialize fsync transaction ids in ext4_new_inode() > Double "ext4: " here :) > > And the "fstests: " prefix in summary can be dropped, "ext4: " prefix is > Okay. > >> We manually modify jbd2 journal_superblock_s.s_sequence to be a very large >> number, which will greatly reduce the time taken to trigger this bug, though >> it seems some too hacked. >> >> Signed-off-by: Wang Xiaoguang >> --- >> tests/ext4/021 | 117 +++++++++++++++++++++++++++++++++++++++++++++++++++++ >> tests/ext4/021.out | 2 + >> tests/ext4/group | 1 + >> 3 files changed, 120 insertions(+) >> create mode 100755 tests/ext4/021 >> create mode 100644 tests/ext4/021.out >> >> diff --git a/tests/ext4/021 b/tests/ext4/021 >> new file mode 100755 >> index 0000000..cdc1524 >> --- /dev/null >> +++ b/tests/ext4/021 >> @@ -0,0 +1,117 @@ >> +#! /bin/bash >> +# FS QA Test 021 >> +# >> +# Regression test for commit: >> +# 688f869 ext4: Initialize fsync transaction ids in ext4_new_inode() >> +# >> +#----------------------------------------------------------------------- >> +# Copyright (c) 2016 Fujitsu. All Rights Reserved. >> +# >> +# This program is free software; you can redistribute it and/or >> +# modify it under the terms of the GNU General Public License as >> +# published by the Free Software Foundation. >> +# >> +# This program is distributed in the hope that it would be useful, >> +# but WITHOUT ANY WARRANTY; without even the implied warranty of >> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> +# GNU General Public License for more details. >> +# >> +# You should have received a copy of the GNU General Public License >> +# along with this program; if not, write the Free Software Foundation, >> +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA >> +#----------------------------------------------------------------------- >> +# >> + >> +seq=`basename $0` >> +seqres=$RESULT_DIR/$seq >> +echo "QA output created by $seq" >> + >> +here=`pwd` >> +tmp=/tmp/$$ >> +status=1 # failure is the default! >> +trap "_cleanup; exit \$status" 0 1 2 3 15 >> + >> +_cleanup() >> +{ >> + cd / >> + rm -f $tmp.* >> + $UMOUNT_PROG $loop_mnt >> + _destroy_loop_device $loop_dev1 >> + _destroy_loop_device $loop_dev2 >> + rm -rf $loop_mnt >> + rm -f $fs_img1 $fs_img2 >> +} >> + >> +# get standard environment, filters and checks >> +. ./common/rc >> + >> +# remove previous $seqres.full before test >> +rm -f $seqres.full >> + >> +# real QA test starts here >> +_supported_fs ext4 >> +_supported_os Linux >> +_require_test >> +_require_loop >> + >> +BLOCKSIZE=1024 >> +loop_mnt=$TEST_DIR/$seq.$$.mnt >> +fs_img1=$TEST_DIR/$seq.$$.img1 >> +fs_img2=$TEST_DIR/$seq.$$.img2 >> +mkdir $loop_mnt >> +$XFS_IO_PROG -f -c "truncate 128m" $fs_img1 >>$seqres.full 2>&1 >> +$XFS_IO_PROG -f -c "truncate 16m" $fs_img2 >>$seqres.full 2>&1 >> + >> +loop_dev1=`_create_loop_device $fs_img1` >> +loop_dev2=`_create_loop_device $fs_img2` > You're using two loop devices and one is used as external journal > device, I think test on SCRATCH_DEV should be fine, e.g. > > _scratch_mkfs_sized a 8M ext4 filesystem, then use a script to find the > journal superblock on disk, then modify the journal.s_sequence according > to the location of journal superblock and the offset of s_sequence to > it. I use the following script to do all this: > > #/bin/bash > dev=$1 > mkfs -t ext4 $dev 8M > blocksize=`dumpe2fs -h $dev 2>/dev/null | grep "Block size" | awk '{print $3}'` > offset=0 > found=0 > # this is the jbd2 journal superblock magic number on disk, in big endian > magic="c0 3b 39 98" > > # 8M in bytes > filesize=$((8 * 1024 * 1024)) > while [ $offset -lt $filesize ]; do > if | grep -i "$magic";then > echo "Found journal: $offset" > found=1 > break > fi > offset=$((offset + blocksize)) > done Thanks for your script, but I wonder whether there will be some other metadata which would have the same magic number "c0 3b 39 98", such as ext4 super_block or block_group_description. Regards, Xiaoguang Wang > > # Overwrite journal.s_squence to 0x 81d1a480 > # 0x81d1a480 is hex form of 2178000000, and jbd2 journal is big endian on > # disk, the s_squence offset to the beginning of journal superblock is 24 > xfs_io -c "pwrite -S 0x81 $((offset+24)) 1" \ > -c "pwrite -S 0xd1 $((offset+25)) 1" \ > -c "pwrite -S 0xa4 $((offset+26)) 1" \ > -c "pwrite -S 0x80 $((offset+27)) 1" $dev > > > This way, we don't have to use loop device nor external journal device, > and don't have to test on fixed block size ext4, SCRATCH_DEV just works. > >> + >> +_mkfs_dev -b $BLOCKSIZE -O journal_dev $loop_dev2 >>$seqres.full 2>&1 >> +_mkfs_dev -b $BLOCKSIZE -J device=$loop_dev2 $loop_dev1 >>$seqres.full 2>&1 >> + >> +# Below command will modify jbd2 journal transaction id to be 2178000000, >> +# which will reduce the time taken to trigger this bug. When ext4 fs block >> +# size is 1024, journal superblock will start at offset 2048, and >> +# journal_superblock_s.s_sequence will start at offset 2072. After this >> +# modification, jbd2 will will start to run with a initial transaction id >> +# 2178000000. >> +echo 81d1a480 | xxd -r -ps | dd of=$loop_dev2 bs=4 count=1 seek=518 >/dev/null 2>&1 >> + >> +trans_id=$(dumpe2fs $loop_dev2 2>/dev/null | grep "Journal sequence" | \ >> + awk -F ":" '{print $2}') >> +trans_id=$((trans_id)) > I think this is unnecessary, just print the hex form. > >> +if [ $trans_id -ne 2178000000 ]; then >> + echo "fail to set initial transaction id to 2178000000" >> + exit >> +fi > This is not needed, because.. > >> +echo "Initial transaction id is $trans_id" > You have this in golden output, when trans_id goes wrong, it will be > caught by golden image. > >> + >> +_mount $loop_dev1 $loop_mnt >> +cd $loop_mnt >> + >> +cat >do_fdatasync.c <> +#include >> +#include >> +#include >> +#include >> + >> +void main(void) >> +{ >> + int fd; >> + >> + fd = open("testfile", O_RDWR | O_CREAT | O_EXCL); >> + while (1) >> + fdatasync(fd); >> +} >> +EOF >> +gcc -o do_fdatasync do_fdatasync.c >> $seqres.full 2>&1 || \ >> + _notrun "Could not compile test program (see end of $seqres.full)" >> + >> +./do_fdatasync & >> +child_process=$! > No need to write a temporary c program, calling xfs_io -c "fdatasync" in > a loop is good enough. > >> + >> +sleep 60 >> +kill $child_process >/dev/null 2>&1 > In my test, the test triggers WARNINGs (seems not panic every time) > almost as soon as the fdatasync loop runs. I think 10s is long enough. > >> + >> +# success, all done >> +status=0 >> +exit >> diff --git a/tests/ext4/021.out b/tests/ext4/021.out >> new file mode 100644 >> index 0000000..ee3e81d >> --- /dev/null >> +++ b/tests/ext4/021.out >> @@ -0,0 +1,2 @@ >> +QA output created by 021 >> +Initial transaction id is 2178000000 >> diff --git a/tests/ext4/group b/tests/ext4/group >> index 9e28159..7736da1 100644 >> --- a/tests/ext4/group >> +++ b/tests/ext4/group >> @@ -23,6 +23,7 @@ >> 018 fuzzers >> 019 fuzzers >> 020 auto quick ioctl rw >> +021 auto > If it runs for 10s, quick group can be added. > > Thanks, > Eryu > >> 271 auto rw quick >> 301 aio auto ioctl rw stress >> 302 aio auto ioctl rw stress >> -- >> 2.5.0 >> >> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe fstests" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >