From a5e74b841930bec78a4684ab9f208b2ddfe7c736 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Mon, 26 Oct 2009 14:24:34 -0800 Subject: [PATCH] x86: Force irq complete move during cpu offline When a cpu goes offline, fixup_irqs() try to move irq's currently destined to the offline cpu to a new cpu. But this attempt will fail if the irq is recently moved to this cpu and the irq still hasn't arrived at this cpu (for non intr-remapping platforms this is when we free the vector allocation at the previous destination) that is about to go offline. This will endup with the interrupt subsystem still pointing the irq to the offline cpu, causing that irq to not work any more. Fix this by forcing the irq to complete its move (its been a long time we moved the irq to this cpu which we are offlining now) and then move this irq to a new cpu before this cpu goes offline. Signed-off-by: Suresh Siddha Acked-by: Gary Hade Cc: Eric W. Biederman LKML-Reference: <20091026230001.848830905@sbs-t61.sc.intel.com> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/irq.h | 1 + arch/x86/kernel/apic/io_apic.c | 18 +++++++++++++++--- arch/x86/kernel/irq.c | 7 +++++++ 3 files changed, 23 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h index ddda6cbed6f4..ffd700ff5dcb 100644 --- a/arch/x86/include/asm/irq.h +++ b/arch/x86/include/asm/irq.h @@ -34,6 +34,7 @@ static inline int irq_canonicalize(int irq) #ifdef CONFIG_HOTPLUG_CPU #include extern void fixup_irqs(void); +extern void irq_force_complete_move(int); #endif extern void (*generic_interrupt_extension)(void); diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index e9e5b02c3af2..4e886efd9a15 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2450,21 +2450,33 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void) irq_exit(); } -static void irq_complete_move(struct irq_desc **descp) +static void __irq_complete_move(struct irq_desc **descp, unsigned vector) { struct irq_desc *desc = *descp; struct irq_cfg *cfg = desc->chip_data; - unsigned vector, me; + unsigned me; if (likely(!cfg->move_in_progress)) return; - vector = ~get_irq_regs()->orig_ax; me = smp_processor_id(); if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain)) send_cleanup_vector(cfg); } + +static void irq_complete_move(struct irq_desc **descp) +{ + __irq_complete_move(descp, ~get_irq_regs()->orig_ax); +} + +void irq_force_complete_move(int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + struct irq_cfg *cfg = desc->chip_data; + + __irq_complete_move(&desc, cfg->vector); +} #else static inline void irq_complete_move(struct irq_desc **descp) {} #endif diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c index 342bcbca19b4..b10a5e1da06c 100644 --- a/arch/x86/kernel/irq.c +++ b/arch/x86/kernel/irq.c @@ -305,6 +305,13 @@ void fixup_irqs(void) continue; } + /* + * Complete the irq move. This cpu is going down and for + * non intr-remapping case, we can't wait till this interrupt + * arrives at this cpu before completing the irq move. + */ + irq_force_complete_move(irq); + if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) { break_affinity = 1; affinity = cpu_all_mask; -- GitLab