| From: Yong Zhang <yong.zhang@windriver.com> |
| Date: Wed, 11 Jul 2012 22:05:21 +0000 |
| Subject: perf: Make swevent hrtimer run in irq instead of softirq |
| |
| Otherwise we get a deadlock like below: |
| |
| [ 1044.042749] BUG: scheduling while atomic: ksoftirqd/21/141/0x00010003 |
| [ 1044.042752] INFO: lockdep is turned off. |
| [ 1044.042754] Modules linked in: |
| [ 1044.042757] Pid: 141, comm: ksoftirqd/21 Tainted: G W 3.4.0-rc2-rt3-23676-ga723175-dirty #29 |
| [ 1044.042759] Call Trace: |
| [ 1044.042761] <IRQ> [<ffffffff8107d8e5>] __schedule_bug+0x65/0x80 |
| [ 1044.042770] [<ffffffff8168978c>] __schedule+0x83c/0xa70 |
| [ 1044.042775] [<ffffffff8106bdd2>] ? prepare_to_wait+0x32/0xb0 |
| [ 1044.042779] [<ffffffff81689a5e>] schedule+0x2e/0xa0 |
| [ 1044.042782] [<ffffffff81071ebd>] hrtimer_wait_for_timer+0x6d/0xb0 |
| [ 1044.042786] [<ffffffff8106bb30>] ? wake_up_bit+0x40/0x40 |
| [ 1044.042790] [<ffffffff81071f20>] hrtimer_cancel+0x20/0x40 |
| [ 1044.042794] [<ffffffff8111da0c>] perf_swevent_cancel_hrtimer+0x3c/0x50 |
| [ 1044.042798] [<ffffffff8111da31>] task_clock_event_stop+0x11/0x40 |
| [ 1044.042802] [<ffffffff8111da6e>] task_clock_event_del+0xe/0x10 |
| [ 1044.042805] [<ffffffff8111c568>] event_sched_out+0x118/0x1d0 |
| [ 1044.042809] [<ffffffff8111c649>] group_sched_out+0x29/0x90 |
| [ 1044.042813] [<ffffffff8111ed7e>] __perf_event_disable+0x18e/0x200 |
| [ 1044.042817] [<ffffffff8111c343>] remote_function+0x63/0x70 |
| [ 1044.042821] [<ffffffff810b0aae>] generic_smp_call_function_single_interrupt+0xce/0x120 |
| [ 1044.042826] [<ffffffff81022bc7>] smp_call_function_single_interrupt+0x27/0x40 |
| [ 1044.042831] [<ffffffff8168d50c>] call_function_single_interrupt+0x6c/0x80 |
| [ 1044.042833] <EOI> [<ffffffff811275b0>] ? perf_event_overflow+0x20/0x20 |
| [ 1044.042840] [<ffffffff8168b970>] ? _raw_spin_unlock_irq+0x30/0x70 |
| [ 1044.042844] [<ffffffff8168b976>] ? _raw_spin_unlock_irq+0x36/0x70 |
| [ 1044.042848] [<ffffffff810702e2>] run_hrtimer_softirq+0xc2/0x200 |
| [ 1044.042853] [<ffffffff811275b0>] ? perf_event_overflow+0x20/0x20 |
| [ 1044.042857] [<ffffffff81045265>] __do_softirq_common+0xf5/0x3a0 |
| [ 1044.042862] [<ffffffff81045c3d>] __thread_do_softirq+0x15d/0x200 |
| [ 1044.042865] [<ffffffff81045dda>] run_ksoftirqd+0xfa/0x210 |
| [ 1044.042869] [<ffffffff81045ce0>] ? __thread_do_softirq+0x200/0x200 |
| [ 1044.042873] [<ffffffff81045ce0>] ? __thread_do_softirq+0x200/0x200 |
| [ 1044.042877] [<ffffffff8106b596>] kthread+0xb6/0xc0 |
| [ 1044.042881] [<ffffffff8168b97b>] ? _raw_spin_unlock_irq+0x3b/0x70 |
| [ 1044.042886] [<ffffffff8168d994>] kernel_thread_helper+0x4/0x10 |
| [ 1044.042889] [<ffffffff8107d98c>] ? finish_task_switch+0x8c/0x110 |
| [ 1044.042894] [<ffffffff8168b97b>] ? _raw_spin_unlock_irq+0x3b/0x70 |
| [ 1044.042897] [<ffffffff8168bd5d>] ? retint_restore_args+0xe/0xe |
| [ 1044.042900] [<ffffffff8106b4e0>] ? kthreadd+0x1e0/0x1e0 |
| [ 1044.042902] [<ffffffff8168d990>] ? gs_change+0xb/0xb |
| |
| Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> |
| Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> |
| Cc: Steven Rostedt <rostedt@goodmis.org> |
| Link: http://lkml.kernel.org/r/1341476476-5666-1-git-send-email-yong.zhang0@gmail.com |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| Signed-off-by: Steven Rostedt <rostedt@goodmis.org> |
| |
| --- |
| kernel/events/core.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| --- a/kernel/events/core.c |
| +++ b/kernel/events/core.c |
| @@ -7261,6 +7261,7 @@ static void perf_swevent_init_hrtimer(st |
| |
| hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); |
| hwc->hrtimer.function = perf_swevent_hrtimer; |
| + hwc->hrtimer.irqsafe = 1; |
| |
| /* |
| * Since hrtimers have a fixed rate, we can do a static freq->period |
