From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: [PATCH v9 5/9] KVM: arm/arm64: Support a vgic interrupt line level sample function Date: Wed, 20 Dec 2017 12:36:02 +0100 Message-ID: <20171220113606.7030-6-christoffer.dall@linaro.org> References: <20171220113606.7030-1-christoffer.dall@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Marc Zyngier , Andre Przywara , kvm@vger.kernel.org To: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Return-path: In-Reply-To: <20171220113606.7030-1-christoffer.dall@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org 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 Reviewed-by: Eric Auger Signed-off-by: Christoffer Dall --- include/kvm/arm_vgic.h | 13 ++++++++++++- virt/kvm/arm/arch_timer.c | 3 ++- virt/kvm/arm/vgic/vgic.c | 13 +++++++++---- 3 files changed, 23 insertions(+), 6 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 9376fe03bf2e..fb0533ed903d 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -834,7 +834,8 @@ 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 4318e9edd075..d57b3bf8eb36 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -144,13 +144,15 @@ void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq) kfree(irq); } -/* Get the input level of a mapped IRQ directly from the physical GIC */ bool vgic_get_phys_line_level(struct vgic_irq *irq) { bool line_level; 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 +438,8 @@ 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 +459,7 @@ 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 +468,11 @@ 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 +481,7 @@ 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); -- 2.14.2 From mboxrd@z Thu Jan 1 00:00:00 1970 From: christoffer.dall@linaro.org (Christoffer Dall) Date: Wed, 20 Dec 2017 12:36:02 +0100 Subject: [PATCH v9 5/9] KVM: arm/arm64: Support a vgic interrupt line level sample function In-Reply-To: <20171220113606.7030-1-christoffer.dall@linaro.org> References: <20171220113606.7030-1-christoffer.dall@linaro.org> Message-ID: <20171220113606.7030-6-christoffer.dall@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Reviewed-by: Eric Auger Signed-off-by: Christoffer Dall --- include/kvm/arm_vgic.h | 13 ++++++++++++- virt/kvm/arm/arch_timer.c | 3 ++- virt/kvm/arm/vgic/vgic.c | 13 +++++++++---- 3 files changed, 23 insertions(+), 6 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 9376fe03bf2e..fb0533ed903d 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -834,7 +834,8 @@ 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 4318e9edd075..d57b3bf8eb36 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -144,13 +144,15 @@ void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq) kfree(irq); } -/* Get the input level of a mapped IRQ directly from the physical GIC */ bool vgic_get_phys_line_level(struct vgic_irq *irq) { bool line_level; 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 +438,8 @@ 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 +459,7 @@ 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 +468,11 @@ 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 +481,7 @@ 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); -- 2.14.2