lkml.org 
[lkml]   [2009]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: next-20090310: ext4 hangs
> 2009/3/10 Theodore Tso <tytso@mit.edu>:
> > On Tue, Mar 10, 2009 at 05:18:55PM +0300, Alexander Beregalov wrote:
> >> > Thanks for reporting this; does it show up on stock 2.6.29-rc7?
> >> No, I can not reproduce it.
> >> It is a slow system, I would not like to bisect it, only if it is the
> >> last possibility.
> >
> > Just to be clear; you weren't able to reproduce it on stock 2.6.29-rc7
> > ---- does it reproduce easily on linux-next?
> Right.
> But now I am not sure 2.6.29-rc7 is not affected, I will try to
> reproduce it again.
>
> >
> > Next question --- does the system hang completely, or just the dbench
> > process (and probably any process that tries touching the filesystem
> System is responsible.
> > that's hung up)?  Do you have a serial console, or someone of
> > recording all of the dumps coming from sysrq-t?  The two stack traces
> I can read dmesg.
> > you gave weren't the ones causing the problem, but rather the ones
> > waiting for the journal lock.
>
> SysRq : Show State
>
> <..>
>
> kjournald2 D 0000000000557a0c 0 1547 2
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [0000000000557a0c] jbd2_journal_commit_transaction+0x208/0x1718
> [000000000055d758] kjournald2+0x14c/0x318
> [0000000000465d34] kthread+0x48/0x7c
> [000000000042b364] kernel_thread+0x3c/0x54
> [0000000000465c88] kthreadd+0xc8/0x12c
> pdflush D 000000000055716c 0 2021 2
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052dd84] ext4_da_writepages+0x1a8/0x404
> [0000000000490ec0] do_writepages+0x40/0x78
> [00000000004d0ff8] __writeback_single_inode+0x198/0x330
> [00000000004d15d8] generic_sync_sb_inodes+0x238/0x3c4
> [00000000004d1984] writeback_inodes+0xb0/0x114
> [00000000004915c0] background_writeout+0xc8/0x114
> [0000000000492004] pdflush+0x128/0x1e0
> [0000000000465d34] kthread+0x48/0x7c
> [000000000042b364] kernel_thread+0x3c/0x54
> [0000000000465c88] kthreadd+0xc8/0x12c
> dbench D 000000000055716c 0 2024 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052a9b8] ext4_dirty_inode+0xd4/0xf0
> [00000000004d1a14] __mark_inode_dirty+0x2c/0x188
> [00000000004c7714] touch_atime+0x160/0x178
> [00000000004c2a3c] vfs_readdir+0x88/0xb0
> [00000000004eab90] compat_sys_getdents+0x3c/0x8c
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2025 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052a9b8] ext4_dirty_inode+0xd4/0xf0
> [00000000004d1a14] __mark_inode_dirty+0x2c/0x188
> [00000000004c7714] touch_atime+0x160/0x178
> [00000000004c2a3c] vfs_readdir+0x88/0xb0
> [00000000004eab90] compat_sys_getdents+0x3c/0x8c
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2026 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052a9b8] ext4_dirty_inode+0xd4/0xf0
> [00000000004d1a14] __mark_inode_dirty+0x2c/0x188
> [00000000004c7714] touch_atime+0x160/0x178
> [000000000048b56c] generic_file_aio_read+0x578/0x620
> [00000000004b5254] do_sync_read+0x90/0xe0
> [00000000004b5c40] vfs_read+0x7c/0x11c
> [00000000004b5d30] SyS_pread64+0x50/0x7c
> [000000000043f778] sys32_pread64+0x20/0x34
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2027 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052a9b8] ext4_dirty_inode+0xd4/0xf0
> [00000000004d1a14] __mark_inode_dirty+0x2c/0x188
> [00000000004c757c] file_update_time+0xe0/0x118
> [000000000048aef4] __generic_file_aio_write_nolock+0x280/0x380
> [000000000048b930] generic_file_aio_write+0x58/0xc8
> [0000000000526274] ext4_file_write+0xa8/0x15c
> [00000000004b5174] do_sync_write+0x90/0xe0
> [00000000004b5a40] vfs_write+0x7c/0x11c
> [00000000004b5b30] SyS_pwrite64+0x50/0x7c
> [000000000043f744] sys32_pwrite64+0x20/0x34
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2028 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052b958] ext4_da_write_begin+0x98/0x1a0
> [000000000048a8dc] generic_file_buffered_write+0xe4/0x2b8
> [000000000048afd0] __generic_file_aio_write_nolock+0x35c/0x380
> [000000000048b930] generic_file_aio_write+0x58/0xc8
> [0000000000526274] ext4_file_write+0xa8/0x15c
> [00000000004b5174] do_sync_write+0x90/0xe0
> [00000000004b5a40] vfs_write+0x7c/0x11c
> [00000000004b5b30] SyS_pwrite64+0x50/0x7c
> [000000000043f744] sys32_pwrite64+0x20/0x34
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055c010 0 2029 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055c010] jbd2_journal_release_jbd_inode+0x94/0xd8
> [0000000000535bb4] ext4_clear_inode+0x2c/0x3c
> [00000000004c7b1c] clear_inode+0xac/0x124
> [0000000000527e48] ext4_free_inode+0x7c/0x3d4
> [000000000052f884] ext4_delete_inode+0x218/0x29c
> [00000000004c86b4] generic_delete_inode+0x8c/0x124
> [00000000004c876c] generic_drop_inode+0x20/0x19c
> [00000000004c77a4] iput+0x78/0x88
> [00000000004c0200] do_unlinkat+0xf8/0x154
> [00000000004c0270] SyS_unlink+0x14/0x24
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055cf84 0 2030 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055cf84] jbd2_log_wait_commit+0x144/0x1a8
> [0000000000555cdc] jbd2_journal_stop+0x32c/0x37c
> [0000000000557594] jbd2_journal_force_commit+0x34/0x48
> [0000000000536d14] ext4_force_commit+0x30/0x50
> [00000000005296b8] ext4_write_inode+0x80/0xa0
> [00000000004d1044] __writeback_single_inode+0x1e4/0x330
> [00000000004d11b0] sync_inode+0x20/0x40
> [00000000005263ec] ext4_sync_file+0xc4/0x118
> [00000000004d46f0] vfs_fsync+0x6c/0xa0
> [00000000004d474c] do_fsync+0x28/0x44
> [00000000004d47a4] SyS_fsync+0x14/0x28
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2031 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052b958] ext4_da_write_begin+0x98/0x1a0
> [000000000048a8dc] generic_file_buffered_write+0xe4/0x2b8
> [000000000048afd0] __generic_file_aio_write_nolock+0x35c/0x380
> [000000000048b930] generic_file_aio_write+0x58/0xc8
> [0000000000526274] ext4_file_write+0xa8/0x15c
> [00000000004b5174] do_sync_write+0x90/0xe0
> [00000000004b5a40] vfs_write+0x7c/0x11c
> [00000000004b5b30] SyS_pwrite64+0x50/0x7c
> [000000000043f744] sys32_pwrite64+0x20/0x34
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2032 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052a9b8] ext4_dirty_inode+0xd4/0xf0
> [00000000004d1a14] __mark_inode_dirty+0x2c/0x188
> [00000000004c7714] touch_atime+0x160/0x178
> [00000000004c2a3c] vfs_readdir+0x88/0xb0
> [00000000004eab90] compat_sys_getdents+0x3c/0x8c
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
> dbench D 000000000055716c 0 2033 1
> Call Trace:
> [0000000000768bcc] schedule+0x18/0x40
> [000000000055716c] start_this_handle+0x374/0x508
> [0000000000557500] jbd2_journal_start+0xbc/0x11c
> [000000000053a438] ext4_journal_start_sb+0x5c/0x84
> [000000000052a9b8] ext4_dirty_inode+0xd4/0xf0
> [00000000004d1a14] __mark_inode_dirty+0x2c/0x188
> [00000000004c7714] touch_atime+0x160/0x178
> [000000000048b56c] generic_file_aio_read+0x578/0x620
> [00000000004b5254] do_sync_read+0x90/0xe0
> [00000000004b5c40] vfs_read+0x7c/0x11c
> [00000000004b5d30] SyS_pread64+0x50/0x7c
> [000000000043f778] sys32_pread64+0x20/0x34
> [0000000000406154] linux_sparc_syscall32+0x34/0x40
>
>
> >
> > I don't think is related to BZ #12579, although some of the symptoms
> > look superficially the same.
> >
> >                                                        - Ted
> >
> > P.S.  What are your dbench parameters, and how big is your filesystem,
> > so I can try to reproduce it on my side?  And how long do you
> > typically need to run before this triggers?  Thanks!
>
> It is 2G filesystem, I run
> `dbench -c /usr/share/dbench/client.txt 10` or 5 clients.
>
> Yesterday it happened when I run it for the first time, but today I
> run it 10 times before I got the deadlock.
>
> So, I think I need to try it on 2.6.29-rc7 again.
I've looked into this. Obviously, what's happenning is that we delete
an inode and jbd2_journal_release_jbd_inode() finds inode is just under
writeout in transaction commit and thus it waits. But it gets never woken
up and because it has a handle from the transaction, every one eventually
blocks on waiting for a transaction to finish.
But I don't really see how that can happen. The code is really
straightforward and everything happens under j_list_lock... Strange.

Honza
--
Jan Kara <jack@suse.cz>
SuSE CR Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2009-03-25 16:15    [W:3.646 / U:0.632 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site