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authorMarc Zyngier <marc.zyngier@arm.com>2017-10-27 15:28:49 +0100
committerChristoffer Dall <christoffer.dall@linaro.org>2017-11-10 09:43:22 +0100
commitdf9ba95993b9d59e077aa4613f7a4edd20a4064c (patch)
tree8713bc9daf8417cd984eea21872094fee01a8102
parentbdb2d2ccac65dfee0db8fa4a8247df788a942439 (diff)
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KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking source
The doorbell interrupt is only useful if the vcpu is blocked on WFI. In all other cases, recieving a doorbell interrupt is just a waste of cycles. So let's only enable the doorbell if a vcpu is getting blocked, and disable it when it is unblocked. This is very similar to what we're doing for the background timer. Reviewed-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
-rw-r--r--include/kvm/arm_vgic.h3
-rw-r--r--virt/kvm/arm/arm.c2
-rw-r--r--virt/kvm/arm/vgic/vgic-v4.c18
3 files changed, 23 insertions, 0 deletions
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 2f750c770bf2..8c896540a72c 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -381,4 +381,7 @@ int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int irq,
int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
struct kvm_kernel_irq_routing_entry *irq_entry);
+void kvm_vgic_v4_enable_doorbell(struct kvm_vcpu *vcpu);
+void kvm_vgic_v4_disable_doorbell(struct kvm_vcpu *vcpu);
+
#endif /* __KVM_ARM_VGIC_H */
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 34a15c0c65ab..01e575b9f78b 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -315,11 +315,13 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
{
kvm_timer_schedule(vcpu);
+ kvm_vgic_v4_enable_doorbell(vcpu);
}
void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
kvm_timer_unschedule(vcpu);
+ kvm_vgic_v4_disable_doorbell(vcpu);
}
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 796e00c77903..1375a53054b9 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -233,3 +233,21 @@ out:
mutex_unlock(&its->its_lock);
return ret;
}
+
+void kvm_vgic_v4_enable_doorbell(struct kvm_vcpu *vcpu)
+{
+ if (vgic_supports_direct_msis(vcpu->kvm)) {
+ int irq = vcpu->arch.vgic_cpu.vgic_v3.its_vpe.irq;
+ if (irq)
+ enable_irq(irq);
+ }
+}
+
+void kvm_vgic_v4_disable_doorbell(struct kvm_vcpu *vcpu)
+{
+ if (vgic_supports_direct_msis(vcpu->kvm)) {
+ int irq = vcpu->arch.vgic_cpu.vgic_v3.its_vpe.irq;
+ if (irq)
+ disable_irq(irq);
+ }
+}