diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2015-04-10 11:50:22 +0200 |
|---|---|---|
| committer | Anders Roxell <anders.roxell@linaro.org> | 2015-06-26 22:31:47 +0200 |
| commit | 39aa1f605fe43be8a38c6574bb4d4873b29f8741 (patch) | |
| tree | 34ca59d227da2406aace6eddfee47ab05db4c3aa /arch/x86 | |
| parent | 9740ebf283a198f2a72f34fbd5104600e2656ca9 (diff) | |
kernel/irq_work: fix no_hz deadlock
Invoking NO_HZ's irq_work callback from timer irq is not working very
well if the callback decides to invoke hrtimer_cancel():
|hrtimer_try_to_cancel+0x55/0x5f
|hrtimer_cancel+0x16/0x28
|tick_nohz_restart+0x17/0x72
|__tick_nohz_full_check+0x8e/0x93
|nohz_full_kick_work_func+0xe/0x10
|irq_work_run_list+0x39/0x57
|irq_work_tick+0x60/0x67
|update_process_times+0x57/0x67
|tick_sched_handle+0x4a/0x59
|tick_sched_timer+0x3b/0x64
|__run_hrtimer+0x7a/0x149
|hrtimer_interrupt+0x1cc/0x2c5
and here we deadlock while waiting for the lock which we are holding.
To fix this I'm doing the same thing that upstream is doing: is the
irq_work dedicated IRQ and use it only for what is marked as "hirq"
which should only be the FULL_NO_HZ related work.
Cc: stable-rt@vger.kernel.org
Reported-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ Added back in_irq() check for non PREEMPT_RT configs ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/irq_work.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/arch/x86/kernel/irq_work.c b/arch/x86/kernel/irq_work.c index 3d21f7bd7b42..1de84e3ab4e0 100644 --- a/arch/x86/kernel/irq_work.c +++ b/arch/x86/kernel/irq_work.c @@ -38,7 +38,6 @@ __visible void smp_trace_irq_work_interrupt(struct pt_regs *regs) exiting_irq(); } -#ifndef CONFIG_PREEMPT_RT_FULL void arch_irq_work_raise(void) { #ifdef CONFIG_X86_LOCAL_APIC @@ -49,4 +48,3 @@ void arch_irq_work_raise(void) apic_wait_icr_idle(); #endif } -#endif |