On Monday, 3 of December 2007, Andrew Morton wrote: > On Mon, 3 Dec 2007 15:19:25 +0100 > Ingo Molnar <[EMAIL PROTECTED]> wrote: > > > this patch extends the soft-lockup detector to automatically > > detect hung TASK_UNINTERRUPTIBLE tasks. Such hung tasks are > > printed the following way: > > > > ------------------> > > INFO: task prctl:3042 blocked for more than 120 seconds. > > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message > > prctl D fd5e3793 0 3042 2997 > > f6050f38 00000046 00000001 fd5e3793 00000009 c06d8264 c06dae80 > > 00000286 > > f6050f40 f6050f00 f7d34d90 f7d34fc8 c1e1be80 00000001 f6050000 > > 00000000 > > f7e92d00 00000286 f6050f18 c0489d1a f6050f40 00006605 00000000 > > c0133a5b > > Call Trace: > > [<c04883a5>] schedule_timeout+0x6d/0x8b > > [<c04883d8>] schedule_timeout_uninterruptible+0x15/0x17 > > [<c0133a76>] msleep+0x10/0x16 > > [<c0138974>] sys_prctl+0x30/0x1e2 > > [<c0104c52>] sysenter_past_esp+0x5f/0xa5 > > ======================= > > 2 locks held by prctl/3042: > > #0: (&sb->s_type->i_mutex_key#5){--..}, at: [<c0197d11>] > > do_fsync+0x38/0x7a > > #1: (jbd_handle){--..}, at: [<c01ca3d2>] journal_start+0xc7/0xe9 > > <------------------ > > > > the current default timeout is 120 seconds. Such messages are printed > > up to 10 times per bootup. If the system has crashed already then the > > messages are not printed. > > > > if lockdep is enabled then all held locks are printed as well. > > > > this feature is a natural extension to the softlockup-detector (kernel > > locked up without scheduling) and to the NMI watchdog (kernel locked up > > with IRQs disabled). > > This feature will save one full reporter-developer round-trip during > investigation of a significant number of bug reports. > > It might be more practical if it were to dump the traces for _all_ > D-state processes when it fires - basically an auto-triggered sysrq-W.
Er, it won't play well if that happen when tasks are frozen for suspend. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/