From: Stefano Stabellini Date: Wed, 13 Aug 2014 16:29:39 +0000 (+0100) Subject: xen/arm: physical irq follow virtual irq X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~4478 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=5bd62a757b9e39abc62dcb2a8c0cd2ab429c7c4c;p=xen.git xen/arm: physical irq follow virtual irq Migrate physical irqs to the same physical cpu that is running the vcpu expected to receive the irqs. That is done when enabling irqs, when the guest writes to GICD_ITARGETSR and when Xen migrates a vcpu to a different pcpu. In case of virq migration, if the virq is inflight and in a GICH_LR register already, delay migrating the corresponding physical irq until the virq is EOIed by the guest and the MIGRATING flag has been cleared. This way we make sure that the pcpu running the old vcpu gets interrupted with a new irq of the same kind, clearing the GICH_LR sooner. Introduce a new arch specific function, arch_move_irqs, that is empty on x86 and implements the vgic irq migration code on ARM. arch_move_irqs is going to be called by from sched.c. Signed-off-by: Stefano Stabellini Acked-by: Jan Beulich Acked-by: Julien Grall --- diff --git a/xen/arch/arm/gic-v2.c b/xen/arch/arm/gic-v2.c index 130554206e..da60a41aef 100644 --- a/xen/arch/arm/gic-v2.c +++ b/xen/arch/arm/gic-v2.c @@ -569,9 +569,20 @@ static void gicv2_guest_irq_end(struct irq_desc *desc) /* Deactivation happens in maintenance interrupt / via GICV */ } -static void gicv2_irq_set_affinity(struct irq_desc *desc, const cpumask_t *mask) +static void gicv2_irq_set_affinity(struct irq_desc *desc, const cpumask_t *cpu_mask) { - BUG(); + unsigned int mask; + + ASSERT(!cpumask_empty(cpu_mask)); + + spin_lock(&gicv2.lock); + + mask = gicv2_cpu_mask(cpu_mask); + + /* Set target CPU mask (RAZ/WI on uniprocessor) */ + writeb_gicd(mask, GICD_ITARGETSR + desc->irq); + + spin_unlock(&gicv2.lock); } /* XXX different for level vs edge */ diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c index f5c7c9145e..2aa95005e3 100644 --- a/xen/arch/arm/gic.c +++ b/xen/arch/arm/gic.c @@ -382,7 +382,11 @@ static void gic_update_one_lr(struct vcpu *v, int i) gic_raise_guest_irq(v, irq, p->priority); else { list_del_init(&p->inflight); - clear_bit(GIC_IRQ_GUEST_MIGRATING, &p->status); + if ( test_and_clear_bit(GIC_IRQ_GUEST_MIGRATING, &p->status) ) + { + struct vcpu *v_target = vgic_get_target_vcpu(v, irq); + irq_set_affinity(p->desc, cpumask_of(v_target->processor)); + } } } } diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c index 49ca467841..7150c7ace2 100644 --- a/xen/arch/arm/irq.c +++ b/xen/arch/arm/irq.c @@ -134,6 +134,12 @@ static inline struct domain *irq_get_domain(struct irq_desc *desc) return desc->action->dev_id; } +void irq_set_affinity(struct irq_desc *desc, const cpumask_t *cpu_mask) +{ + if ( desc != NULL ) + desc->handler->set_affinity(desc, cpu_mask); +} + int request_irq(unsigned int irq, unsigned int irqflags, void (*handler)(int, void *, struct cpu_user_regs *), const char *devname, void *dev_id) diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c index ed7108eab2..2319d714a2 100644 --- a/xen/arch/arm/vgic.c +++ b/xen/arch/arm/vgic.c @@ -182,6 +182,7 @@ void vgic_migrate_irq(struct vcpu *old, struct vcpu *new, unsigned int irq) if ( list_empty(&p->inflight) ) { + irq_set_affinity(p->desc, cpumask_of(new->processor)); spin_unlock_irqrestore(&old->arch.vgic.lock, flags); return; } @@ -191,6 +192,7 @@ void vgic_migrate_irq(struct vcpu *old, struct vcpu *new, unsigned int irq) clear_bit(GIC_IRQ_GUEST_QUEUED, &p->status); list_del_init(&p->lr_queue); list_del_init(&p->inflight); + irq_set_affinity(p->desc, cpumask_of(new->processor)); spin_unlock_irqrestore(&old->arch.vgic.lock, flags); vgic_vcpu_inject_irq(new, irq); return; @@ -203,6 +205,24 @@ void vgic_migrate_irq(struct vcpu *old, struct vcpu *new, unsigned int irq) spin_unlock_irqrestore(&old->arch.vgic.lock, flags); } +void arch_move_irqs(struct vcpu *v) +{ + const cpumask_t *cpu_mask = cpumask_of(v->processor); + struct domain *d = v->domain; + struct pending_irq *p; + struct vcpu *v_target; + int i; + + for ( i = 32; i < (d->arch.vgic.nr_lines + 32); i++ ) + { + v_target = vgic_get_target_vcpu(v, i); + p = irq_to_pending(v_target, i); + + if ( v_target == v && !test_bit(GIC_IRQ_GUEST_MIGRATING, &p->status) ) + irq_set_affinity(p->desc, cpu_mask); + } +} + void vgic_disable_irqs(struct vcpu *v, uint32_t r, int n) { struct domain *d = v->domain; @@ -260,6 +280,7 @@ void vgic_enable_irqs(struct vcpu *v, uint32_t r, int n) } if ( p->desc != NULL ) { + irq_set_affinity(p->desc, cpumask_of(v_target->processor)); spin_lock_irqsave(&p->desc->lock, flags); p->desc->handler->enable(p->desc); spin_unlock_irqrestore(&p->desc->lock, flags); diff --git a/xen/include/asm-arm/irq.h b/xen/include/asm-arm/irq.h index e567f712ec..e877334c08 100644 --- a/xen/include/asm-arm/irq.h +++ b/xen/include/asm-arm/irq.h @@ -42,12 +42,15 @@ void init_secondary_IRQ(void); int route_irq_to_guest(struct domain *d, unsigned int irq, const char *devname); +void arch_move_irqs(struct vcpu *v); /* Set IRQ type for an SPI */ int irq_set_spi_type(unsigned int spi, unsigned int type); int platform_get_irq(const struct dt_device_node *device, int index); +void irq_set_affinity(struct irq_desc *desc, const cpumask_t *cpu_mask); + #endif /* _ASM_HW_IRQ_H */ /* * Local variables: diff --git a/xen/include/asm-x86/irq.h b/xen/include/asm-x86/irq.h index 9066d3892c..d3c55f362f 100644 --- a/xen/include/asm-x86/irq.h +++ b/xen/include/asm-x86/irq.h @@ -197,4 +197,6 @@ void cleanup_domain_irq_mapping(struct domain *); bool_t cpu_has_pending_apic_eoi(void); +static inline void arch_move_irqs(struct vcpu *v) { } + #endif /* _ASM_HW_IRQ_H */