Thanks - the hints are much appreciated. -----Original Message----- From: Thomas Gleixner [mailto:tglx@xxxxxxxxxxxxx] Sent: Wednesday, February 13, 2013 7:34 AM To: Staffan Tjernstrom Cc: linux-rt-users@xxxxxxxxxxxxxxx Subject: Re: How to decode output from sysrq - t On Mon, 11 Feb 2013, Staffan Tjernstrom wrote: > I'm trying to plow through the output from sysrq - t on a system where > I think we may have a rouge high-priority call to the file system from > userspace causing a priority inversion issue. Abby hangs in a futex_wait() which has nothing to do with file systems. > For the particular instance I'm looking at, it would appear that the > "other" half of the hang is the auditd daemon. Well, there is no indication that auditd blocks on the same futex as Abby and I really would wonder if that's the case. > My question is this - is the format of the output between the task > name and the call trace documented anywhere? Or where in the code > should I look for it? > auditd S ffff880418b967c0 0 2998 1 0x00000000 sched_show_task() > ffff880418479bf8 0000000000000086 00000000000000d0 ffff880418478000 > ffff880418478010 ffff880418478010 ffff880418479fd8 ffff880418478000 > ffff880418478000 ffff880418478000 ffff88041e3380c0 ffff880418b96400 show_stack() > Call Trace: > [<ffffffff814e1aae>] schedule+0x2e/0xa0 [<ffffffff810898dc>] > futex_wait_queue_me+0xcc/0x110 [<ffffffff81089ba5>] > futex_wait+0x195/0x290 [<ffffffff8104b4fb>] ? > migrate_enable+0xdb/0x1d0 [<ffffffff810892a6>] ? > futex_wake+0x126/0x140 [<ffffffff8108ab34>] do_futex+0x124/0xaf0 > [<ffffffff8104b4fb>] ? migrate_enable+0xdb/0x1d0 [<ffffffffa019463f>] > ? ext2_statfs+0xef/0x180 [ext2] [<ffffffff8117c388>] ? > do_statfs_native+0x98/0xb0 [<ffffffff8108b57b>] sys_futex+0x7b/0x170 > [<ffffffff814eab2b>] system_call_fastpath+0x16/0x1b > > Abby S ffff8804181849c0 0 30761 30740 0x00000080 > ffff880418ac9bf8 0000000000000086 ffff880400000000 ffff880418ac8000 > ffff880418ac8010 ffff880418ac8010 ffff880418ac9fd8 ffff880418ac8000 > ffff880418ac8000 ffff880418ac8000 ffffffff81a10020 ffff880418184600 > Call Trace: > [<ffffffff814e1aae>] schedule+0x2e/0xa0 [<ffffffff810898dc>] > futex_wait_queue_me+0xcc/0x110 [<ffffffff81089ba5>] > futex_wait+0x195/0x290 [<ffffffff81079410>] ? update_rmtp+0x80/0x80 > [<ffffffff8108ab34>] do_futex+0x124/0xaf0 [<ffffffff8114b5ca>] ? > do_sync_write+0xea/0x130 [<ffffffff8114cc57>] ? fget_light+0x97/0xf0 > [<ffffffff8118a7ea>] ? fsnotify+0x1ea/0x320 [<ffffffff8108b57b>] > sys_futex+0x7b/0x170 [<ffffffff814eab2b>] > system_call_fastpath+0x16/0x1b -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
