| Message ID | 63ADC13FD55D6546B7DECE290D39E37342E73E73@H3CMLB12-EX.srv.huawei-3com.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
The patch is malformed...
BTW, I'd like ML_ERROR level log rather ML_KTHREAD, because journal
abort at least should alert filesystem administrator, also this will discard
some transactions.
So how about:
if (status < 0) {
mlog(ML_ERROR, "journal is already abort and cannot be "
"flushed any more. So ignore the pending "
" transactions to avoid blocking ocfs2 unmount.\n");
atomic_set(&journal->j_num_trans, 0);
}
Thanks,
Joseph
On 17/1/11 10:16, Gechangwei wrote:
> Hi,
>
> As prior e-mail described, umount would hang after journal flushing failure.
>
> When journal flushing in ocfs2_commit_cache() fails, following umount
> procedure at stage of shutting journal may be blocked due to non-zero
> transactions number.
>
> Once jbd2_journal_flush() fails, the journal will be marked as ABORT
> state within JBD2. There is no way to come back afterwards.
>
> So there is no chance to set transactions number to zero, thus, shutting
> journal may be blocked .
>
> ocfs2_commit_thread()
>
> ocfs2_commit_cache()
>
> jbd2_journal_flush() -> failure takes journal into ABORT state,
> thus, transaction number will never set to zero
>
>
>
> The back trace is cited blow:
>
> [<ffffffff8109de0c>] kthread_stop+0x4c/0x150
> [<ffffffffc056a887>] ocfs2_journal_shutdown+0xa7/0x400 [ocfs2]
> [<ffffffffc059fbde>] ocfs2_dismount_volume+0xbe/0x4a0 [ocfs2]
> [<ffffffffc059fff7>] ocfs2_put_super+0x37/0xb0 [ocfs2]
> [<ffffffff8120534e>] generic_shutdown_super+0x7e/0x110
> [<ffffffff81205410>] kill_block_super+0x30/0x80
> [<ffffffff81205669>] deactivate_locked_super+0x59/0x90
> [<ffffffff812062ee>] deactivate_super+0x4e/0x70
> [<ffffffff81222423>] cleanup_mnt+0x43/0x90
> [<ffffffff812224c2>] __cleanup_mnt+0x12/0x20
> [<ffffffff8109c247>] task_work_run+0xb7/0xf0
> [<ffffffff81016f7c>] do_notify_resume+0x8c/0xa0
> [<ffffffff817f8384>] int_signal+0x12/0x17
> [<ffffffffffffffff>] 0xffffffffffffffff
>
>
> To solve this issue, I propose an improved version of patch referring to
> Andrew's and Joseph's comments.
>
> Any more comments is welcomed as always.
>
>
> From f3315307dd2a30da138383340689a81708134a44 Mon Sep 17 00:00:00 2001
> From: Changwei Ge <ge.changwei@h3c.com>
> Date: Wed, 11 Jan 2017 09:05:35 +0800
> Subject: [PATCH v2] fix umount hang after journal flushing failure
>
> Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
> ---
> fs/ocfs2/journal.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
> index a244f14..9a6b234 100644
> --- a/fs/ocfs2/journal.c
> +++ b/fs/ocfs2/journal.c
> @@ -2315,6 +2315,24 @@ static int ocfs2_commit_thread(void *arg)
> "commit_thread: %u transactions pending on "
> "shutdown\n",
> atomic_read(&journal->j_num_trans));
> +
> + if (status < 0) {
> + mlog(ML_KTHREAD,
> + "Although %u transactions left,
> journal must be shut down right now.\n",
> + atomic_read(&journal->j_num_trans));
> + /*
> + * This may a litte hacky, however, no
> chance
> + * for ocfs2/journal to decrease this
> variable
> + * thourgh commit-thread. I have to do so to
> + * avoid umount hang after journal flushing
> + * failure. Since jounral has been
> marked ABORT
> + * within jbd2_journal_flush, commit
> cache will
> + * never do any real work to flush
> journal to
> + * disk.Set t to ZERO so that umount will
> + * continue during shutting downjournal
> + */
> + atomic_set(&journal->j_num_trans, 0);
> + }
> }
> }
>
> --
> 1.7.9.5
>
>
> Thanks.
>
> Br.
>
> Changwei
>
>
>
> -------------------------------------------------------------------------------------------------------------------------------------
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diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c index a244f14..9a6b234 100644 --- a/fs/ocfs2/journal.c +++ b/fs/ocfs2/journal.c @@ -2315,6 +2315,24 @@ static int ocfs2_commit_thread(void *arg) "commit_thread: %u transactions pending on " "shutdown\n", atomic_read(&journal->j_num_trans)); + + if (status < 0) { + mlog(ML_KTHREAD, + "Although %u transactions left, journal must be shut down right now.\n", + atomic_read(&journal->j_num_trans)); + /* + * This may a litte hacky, however, no chance + * for ocfs2/journal to decrease this variable + * thourgh commit-thread. I have to do so to + * avoid umount hang after journal flushing + * failure. Since jounral has been marked ABORT + * within jbd2_journal_flush, commit cache will + * never do any real work to flush journal to + * disk.Set t to ZERO so that umount will + * continue during shutting downjournal
Hi, As prior e-mail described, umount would hang after journal flushing failure. When journal flushing in ocfs2_commit_cache() fails, following umount procedure at stage of shutting journal may be blocked due to non-zero transactions number. Once jbd2_journal_flush() fails, the journal will be marked as ABORT state within JBD2. There is no way to come back afterwards. So there is no chance to set transactions number to zero, thus, shutting journal may be blocked . ocfs2_commit_thread() ocfs2_commit_cache() jbd2_journal_flush() -> failure takes journal into ABORT state, thus, transaction number will never set to zero The back trace is cited blow: [<ffffffff8109de0c>] kthread_stop+0x4c/0x150 [<ffffffffc056a887>] ocfs2_journal_shutdown+0xa7/0x400 [ocfs2] [<ffffffffc059fbde>] ocfs2_dismount_volume+0xbe/0x4a0 [ocfs2] [<ffffffffc059fff7>] ocfs2_put_super+0x37/0xb0 [ocfs2] [<ffffffff8120534e>] generic_shutdown_super+0x7e/0x110 [<ffffffff81205410>] kill_block_super+0x30/0x80 [<ffffffff81205669>] deactivate_locked_super+0x59/0x90 [<ffffffff812062ee>] deactivate_super+0x4e/0x70 [<ffffffff81222423>] cleanup_mnt+0x43/0x90 [<ffffffff812224c2>] __cleanup_mnt+0x12/0x20 [<ffffffff8109c247>] task_work_run+0xb7/0xf0 [<ffffffff81016f7c>] do_notify_resume+0x8c/0xa0 [<ffffffff817f8384>] int_signal+0x12/0x17 [<ffffffffffffffff>] 0xffffffffffffffff To solve this issue, I propose an improved version of patch referring to Andrew's and Joseph's comments. Any more comments is welcomed as always. From f3315307dd2a30da138383340689a81708134a44 Mon Sep 17 00:00:00 2001 From: Changwei Ge <ge.changwei@h3c.com> Date: Wed, 11 Jan 2017 09:05:35 +0800 Subject: [PATCH v2] fix umount hang after journal flushing failure Signed-off-by: Changwei Ge <ge.changwei@h3c.com> --- fs/ocfs2/journal.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) + */ + atomic_set(&journal->j_num_trans, 0); + } } } -- 1.7.9.5 Thanks. Br. Changwei ------------------------------------------------------------------------------------------------------------------------------------- 本邮件及其附件含有杭州华三通信技术有限公司的保密信息，仅限于发送给上面地址中列出 的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、 或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本 邮件！ This e-mail and its attachments contain confidential information from H3C, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it!