| Message ID | 20171207105418.22428-6-christoffer.dall@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Christoffer, On 07/12/17 11:54, Christoffer Dall wrote: > The GIC sometimes need to sample the physical line of a mapped > interrupt. As we know this to be notoriously slow, provide a callback > function for devices (such as the timer) which can do this much faster > than talking to the distributor, for example by comparing a few > in-memory values. Fall back to the good old method of poking the > physical GIC if no callback is provided. > > Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> > Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> > --- > include/kvm/arm_vgic.h | 13 ++++++++++++- > virt/kvm/arm/arch_timer.c | 3 ++- > virt/kvm/arm/vgic/vgic.c | 12 +++++++++--- > 3 files changed, 23 insertions(+), 5 deletions(-) > > diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h > index 8c896540a72c..cdbd142ca7f2 100644 > --- a/include/kvm/arm_vgic.h > +++ b/include/kvm/arm_vgic.h > @@ -130,6 +130,17 @@ struct vgic_irq { > u8 priority; > enum vgic_irq_config config; /* Level or edge */ > > + /* > + * Callback function pointer to in-kernel devices that can tell us the > + * state of the input level of mapped level-triggered IRQ faster than > + * peaking into the physical GIC. > + * > + * Always called in non-preemptible section and the functions can use > + * kvm_arm_get_running_vcpu() to get the vcpu pointer for private > + * IRQs. > + */ > + bool (*get_input_level)(int vintid); > + > void *owner; /* Opaque pointer to reserve an interrupt > for in-kernel devices. */ > }; > @@ -331,7 +342,7 @@ void kvm_vgic_init_cpu_hardware(void); > int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid, > bool level, void *owner); > int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, > - u32 vintid); > + u32 vintid, bool (*get_input_level)(int vindid)); > int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid); > bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid); > > diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c > index dd5aca05c500..e78ba5e20f74 100644 > --- a/virt/kvm/arm/arch_timer.c > +++ b/virt/kvm/arm/arch_timer.c > @@ -840,7 +840,8 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu) > return -EINVAL; > } > > - ret = kvm_vgic_map_phys_irq(vcpu, host_vtimer_irq, vtimer->irq.irq); > + ret = kvm_vgic_map_phys_irq(vcpu, host_vtimer_irq, vtimer->irq.irq, > + NULL); > if (ret) > return ret; > > diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c > index 607cbbc27a1c..eadabb249d2a 100644 > --- a/virt/kvm/arm/vgic/vgic.c > +++ b/virt/kvm/arm/vgic/vgic.c Nit: the comment "Get the input level of a mapped IRQ directly from the physical GIC" is not strictly correct anymore > @@ -151,6 +151,9 @@ bool vgic_get_phys_line_level(struct vgic_irq *irq) > > BUG_ON(!irq->hw); > > + if (irq->get_input_level) > + return irq->get_input_level(irq->intid); > + > WARN_ON(irq_get_irqchip_state(irq->host_irq, > IRQCHIP_STATE_PENDING, > &line_level)); > @@ -436,7 +439,8 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid, > > /* @irq->irq_lock must be held */ > static int kvm_vgic_map_irq(struct kvm_vcpu *vcpu, struct vgic_irq *irq, > - unsigned int host_irq) > + unsigned int host_irq, > + bool (*get_input_level)(int vindid)) > { > struct irq_desc *desc; > struct irq_data *data; > @@ -456,6 +460,7 @@ static int kvm_vgic_map_irq(struct kvm_vcpu *vcpu, struct vgic_irq *irq, > irq->hw = true; > irq->host_irq = host_irq; > irq->hwintid = data->hwirq; > + irq->get_input_level = get_input_level; > return 0; > } > > @@ -464,10 +469,11 @@ static inline void kvm_vgic_unmap_irq(struct vgic_irq *irq) > { > irq->hw = false; > irq->hwintid = 0; > + irq->get_input_level = NULL; > } > > int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, > - u32 vintid) > + u32 vintid, bool (*get_input_level)(int vindid)) > { > struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid); > unsigned long flags; > @@ -476,7 +482,7 @@ int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, > BUG_ON(!irq); > > spin_lock_irqsave(&irq->irq_lock, flags); > - ret = kvm_vgic_map_irq(vcpu, irq, host_irq); > + ret = kvm_vgic_map_irq(vcpu, irq, host_irq, get_input_level); > spin_unlock_irqrestore(&irq->irq_lock, flags); > vgic_put_irq(vcpu->kvm, irq); > > Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks Eric
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 8c896540a72c..cdbd142ca7f2 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -130,6 +130,17 @@ struct vgic_irq { u8 priority; enum vgic_irq_config config; /* Level or edge */ + /* + * Callback function pointer to in-kernel devices that can tell us the + * state of the input level of mapped level-triggered IRQ faster than + * peaking into the physical GIC. + * + * Always called in non-preemptible section and the functions can use + * kvm_arm_get_running_vcpu() to get the vcpu pointer for private + * IRQs. + */ + bool (*get_input_level)(int vintid); + void *owner; /* Opaque pointer to reserve an interrupt for in-kernel devices. */ }; @@ -331,7 +342,7 @@ void kvm_vgic_init_cpu_hardware(void); int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid, bool level, void *owner); int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, - u32 vintid); + u32 vintid, bool (*get_input_level)(int vindid)); int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid); bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid); diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index dd5aca05c500..e78ba5e20f74 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -840,7 +840,8 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu) return -EINVAL; } - ret = kvm_vgic_map_phys_irq(vcpu, host_vtimer_irq, vtimer->irq.irq); + ret = kvm_vgic_map_phys_irq(vcpu, host_vtimer_irq, vtimer->irq.irq, + NULL); if (ret) return ret; diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c index 607cbbc27a1c..eadabb249d2a 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -151,6 +151,9 @@ bool vgic_get_phys_line_level(struct vgic_irq *irq) BUG_ON(!irq->hw); + if (irq->get_input_level) + return irq->get_input_level(irq->intid); + WARN_ON(irq_get_irqchip_state(irq->host_irq, IRQCHIP_STATE_PENDING, &line_level)); @@ -436,7 +439,8 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid, /* @irq->irq_lock must be held */ static int kvm_vgic_map_irq(struct kvm_vcpu *vcpu, struct vgic_irq *irq, - unsigned int host_irq) + unsigned int host_irq, + bool (*get_input_level)(int vindid)) { struct irq_desc *desc; struct irq_data *data; @@ -456,6 +460,7 @@ static int kvm_vgic_map_irq(struct kvm_vcpu *vcpu, struct vgic_irq *irq, irq->hw = true; irq->host_irq = host_irq; irq->hwintid = data->hwirq; + irq->get_input_level = get_input_level; return 0; } @@ -464,10 +469,11 @@ static inline void kvm_vgic_unmap_irq(struct vgic_irq *irq) { irq->hw = false; irq->hwintid = 0; + irq->get_input_level = NULL; } int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, - u32 vintid) + u32 vintid, bool (*get_input_level)(int vindid)) { struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid); unsigned long flags; @@ -476,7 +482,7 @@ int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, BUG_ON(!irq); spin_lock_irqsave(&irq->irq_lock, flags); - ret = kvm_vgic_map_irq(vcpu, irq, host_irq); + ret = kvm_vgic_map_irq(vcpu, irq, host_irq, get_input_level); spin_unlock_irqrestore(&irq->irq_lock, flags); vgic_put_irq(vcpu->kvm, irq);