On 2011.04.30 at 16:18 +0200, Bruno Prémont wrote: > On Fri, 29 April 2011 Bruno Prémont wrote: > > On Fri, 29 April 2011 Markus Trippelsdorf wrote: > > > On 2011.04.29 at 11:19 +1000, Dave Chinner wrote: > > > > OK, so the common elements here appears to be root filesystems > > > > with small log sizes, which means they are tail pushing all the > > > > time metadata operations are in progress. Definitely seems like a > > > > race in the AIL workqueue trigger mechanism. I'll see if I can > > > > reproduce this and cook up a patch to fix it. > > > > > > Hmm, I'm wondering if this issue is somehow related to the hrtimer bug, > > > that Thomas Gleixner fixed yesterday: > > > http://git.us.kernel.org/?p=linux/kernel/git/tip/linux-2.6-tip.git;a=commit;h=ce31332d3c77532d6ea97ddcb475a2b02dd358b4 > > > http://thread.gmane.org/gmane.linux.kernel.mm/61909/ > > > > > > It also looks similar to the issue that James Bottomley reported > > > earlier: http://thread.gmane.org/gmane.linux.kernel.mm/62185/ > > > > I'm going to see, I've applied Thomas' fix on the box seeing XFS freeze (without > > other changes to kernel). > > Going to run that kernel for the week-end and beyond if it survives to see what > > happens. > > Happened again (after a few hours of uptime), so it definitely is not > caused by hrtimer bug that Thomas Gleixner fixed. I've enabled lock debugging and this is what happened after a few hours uptime. (I can't tell if this is a false positive): ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.39-rc5-00130-g3fd9952 #10 ------------------------------------------------------- kio_file/7364 is trying to acquire lock: (&sb->s_type->i_mutex_key#5/2){+.+...}, at: [<ffffffff81151e4e>] generic_file_splice_write+0xce/0x180 but task is already holding lock: (xfs_iolock_active){++++++}, at: [<ffffffff811d7d05>] xfs_ilock+0x125/0x1f0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (xfs_iolock_active){++++++}: [<ffffffff810ae8a2>] lock_acquire+0x92/0x1f0 [<ffffffff8109d9bf>] down_write_nested+0x2f/0x60 [<ffffffff811d7d05>] xfs_ilock+0x125/0x1f0 [<ffffffff812061d6>] xfs_file_buffered_aio_write+0x66/0x290 [<ffffffff81206561>] xfs_file_aio_write+0x161/0x300 [<ffffffff811261f2>] do_sync_write+0xd2/0x110 [<ffffffff811262df>] vfs_write+0xaf/0x160 [<ffffffff8112646a>] sys_write+0x4a/0x90 [<ffffffff8154cc6b>] system_call_fastpath+0x16/0x1b -> #1 (&sb->s_type->i_mutex_key#5){+.+.+.}: [<ffffffff810ae8a2>] lock_acquire+0x92/0x1f0 [<ffffffff81549981>] mutex_lock_nested+0x51/0x370 [<ffffffff81135afd>] vfs_rename+0xed/0x420 [<ffffffff81136037>] sys_renameat+0x207/0x230 [<ffffffff8113607b>] sys_rename+0x1b/0x20 [<ffffffff8154cc6b>] system_call_fastpath+0x16/0x1b -> #0 (&sb->s_type->i_mutex_key#5/2){+.+...}: [<ffffffff810ac21f>] __lock_acquire+0x169f/0x1b90 [<ffffffff810ae8a2>] lock_acquire+0x92/0x1f0 [<ffffffff81549981>] mutex_lock_nested+0x51/0x370 [<ffffffff81151e4e>] generic_file_splice_write+0xce/0x180 [<ffffffff81205334>] xfs_file_splice_write+0xf4/0x250 [<ffffffff8115024e>] do_splice_from+0x7e/0xb0 [<ffffffff811502a0>] direct_splice_actor+0x20/0x30 [<ffffffff81151fde>] splice_direct_to_actor+0xbe/0x1c0 [<ffffffff81152158>] do_splice_direct+0x78/0x90 [<ffffffff81125f72>] do_sendfile+0x182/0x1d0 [<ffffffff81126f1a>] sys_sendfile64+0x5a/0xb0 [<ffffffff8154cc6b>] system_call_fastpath+0x16/0x1b other info that might help us debug this: 1 lock held by kio_file/7364: #0: (xfs_iolock_active){++++++}, at: [<ffffffff811d7d05>] xfs_ilock+0x125/0x1f0 stack backtrace: Pid: 7364, comm: kio_file Not tainted 2.6.39-rc5-00130-g3fd9952 #10 Call Trace: [<ffffffff81543f4c>] print_circular_bug+0xb8/0xc7 [<ffffffff810ac21f>] __lock_acquire+0x169f/0x1b90 [<ffffffff8115153d>] ? __generic_file_splice_read+0x1cd/0x5c0 [<ffffffff810ae8a2>] lock_acquire+0x92/0x1f0 [<ffffffff81151e4e>] ? generic_file_splice_write+0xce/0x180 [<ffffffff8148de90>] ? sock_def_write_space+0x140/0x140 [<ffffffff81549981>] mutex_lock_nested+0x51/0x370 [<ffffffff81151e4e>] ? generic_file_splice_write+0xce/0x180 [<ffffffff81151e4e>] generic_file_splice_write+0xce/0x180 [<ffffffff81205334>] xfs_file_splice_write+0xf4/0x250 [<ffffffff8120510f>] ? xfs_file_splice_read+0xef/0x220 [<ffffffff8115024e>] do_splice_from+0x7e/0xb0 [<ffffffff811502a0>] direct_splice_actor+0x20/0x30 [<ffffffff81151fde>] splice_direct_to_actor+0xbe/0x1c0 [<ffffffff81150280>] ? do_splice_from+0xb0/0xb0 [<ffffffff81152158>] do_splice_direct+0x78/0x90 [<ffffffff81125f72>] do_sendfile+0x182/0x1d0 [<ffffffff81126f1a>] sys_sendfile64+0x5a/0xb0 [<ffffffff8154cc6b>] system_call_fastpath+0x16/0x1b -- Markus _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
