Messages in this thread Patch in this message | | | From | "Fenghua Yu" <> | Subject | [PATCH 1/8] x86, apic.c: Disable irq0 if CPU enables ARAT for local apic timer | Date | Wed, 5 Oct 2011 09:39:12 -0700 |
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From: Fenghua Yu <fenghua.yu@intel.com>
irq0 won't generate any interrupt after local apic timers is enabled and ARAT is enabled. Disable irq0 in this case. Thus irq0 won't block BSP offline.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> --- arch/x86/kernel/apic/apic.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 52fa563..8813acf 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -506,6 +506,7 @@ static DEFINE_PER_CPU(struct clock_event_device, lapic_events); static void __cpuinit setup_APIC_timer(void) { struct clock_event_device *levt = &__get_cpu_var(lapic_events); + int cpu = smp_processor_id(); if (this_cpu_has(X86_FEATURE_ARAT)) { lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP; @@ -517,6 +518,10 @@ static void __cpuinit setup_APIC_timer(void) levt->cpumask = cpumask_of(smp_processor_id()); clockevents_register_device(levt); + + /* irq0 won't be used any more if CPU supports ARAT feature. */ + if (cpu == 0 && this_cpu_has(X86_FEATURE_ARAT)) + disable_irq(0); } /* -- 1.6.0.3
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