From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
RT-users <linux-rt-users@vger.kernel.org>,
Carsten Emde <cbe@osadl.org>, Yong Zhang <yong.zhang0@gmail.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [patch RT 7/7] perf: Make swevent hrtimer run in irq instead of softirq
Date: Wed, 11 Jul 2012 22:05:21 -0000 [thread overview]
Message-ID: <20120711215612.277149292@linutronix.de> (raw)
In-Reply-To: 20120711214552.036760674@linutronix.de
[-- Attachment #1: perf-make-swevent-hrtimer-run-in-irq-instead-of-softirq.patch --]
[-- Type: text/plain, Size: 3571 bytes --]
From: Yong Zhang <yong.zhang@windriver.com>
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>
---
kernel/events/core.c | 1 +
1 file changed, 1 insertion(+)
Index: linux-stable-rt/kernel/events/core.c
===================================================================
--- linux-stable-rt.orig/kernel/events/core.c
+++ linux-stable-rt/kernel/events/core.c
@@ -5403,6 +5403,7 @@ 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
next prev parent reply other threads:[~2012-07-11 22:05 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-11 22:05 [patch RT 0/7] Various fixes for the stable RT series - part I Thomas Gleixner
2012-07-11 22:05 ` [patch RT 1/7] Latency histogramms: Cope with backwards running local trace clock Thomas Gleixner
2012-07-11 22:05 ` [patch RT 3/7] Disable RT_GROUP_SCHED in PREEMPT_RT_FULL Thomas Gleixner
2012-07-12 2:36 ` Mike Galbraith
2012-07-11 22:05 ` [patch RT 2/7] Latency histograms: Adjust timer, if already elapsed when programmed Thomas Gleixner
2012-07-11 22:05 ` [patch RT 4/7] Latency histograms: Detect another yet overlooked sharedprio condition Thomas Gleixner
2012-07-11 22:05 ` [patch RT 5/7] slab: Prevent local lock deadlock Thomas Gleixner
2012-07-11 22:05 ` [patch RT 6/7] fs, jbd: pull your plug when waiting for space Thomas Gleixner
2012-07-11 22:05 ` Thomas Gleixner [this message]
2012-07-11 23:31 ` [patch RT 0/7] Various fixes for the stable RT series - part I Steven Rostedt
2012-07-12 8:49 ` Thomas Gleixner
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