[PATCH v3 51/59] KVM: arm/arm64: GICv4: Add doorbell interrupt handling
From: Christoffer Dall <hidden>
Date: 2017-08-28 18:19:03
Also in:
kvm, kvmarm, lkml
On Mon, Jul 31, 2017 at 06:26:29PM +0100, Marc Zyngier wrote:
quoted hunk ↗ jump to hunk
When a vPE is not running, a VLPI being made pending results in a doorbell interrupt being delivered. Let's handle this interrupt and update the pending_last flag that indicates that VLPIs are pending. The corresponding vcpu is also kicked into action. Signed-off-by: Marc Zyngier <redacted> --- virt/kvm/arm/vgic/vgic-v4.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c index 534d3051a078..6af3cde6d7d4 100644 --- a/virt/kvm/arm/vgic/vgic-v4.c +++ b/virt/kvm/arm/vgic/vgic-v4.c@@ -21,6 +21,19 @@ #include "vgic.h" +static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info) +{ + struct kvm_vcpu *vcpu = info; + + if (!kvm_vgic_vcpu_pending_irq(vcpu)) { + vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last = true; + kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); + kvm_vcpu_kick(vcpu); + }
Can this ever fire while vgic_v4_init() is running and before te rest of the system has been properly initialized with some entertaining results to follow? (I'm not sure if spurious doorbell non-resident vPE interrupts is a thing or not).
quoted hunk ↗ jump to hunk
+ + return IRQ_HANDLED; +} + int vgic_v4_init(struct kvm *kvm) { struct vgic_dist *dist = &kvm->arch.vgic;@@ -57,16 +70,37 @@ int vgic_v4_init(struct kvm *kvm) return ret; } + kvm_for_each_vcpu(i, vcpu, kvm) { + int irq = dist->its_vm.vpes[i]->irq; + + ret = request_irq(irq, vgic_v4_doorbell_handler, + 0, "vcpu", vcpu); + if (ret) { + kvm_err("failed to allocate vcpu IRQ%d\n", irq); + dist->its_vm.nr_vpes = i;
That's a neat trick for the error handling. Might deserve a tiny comment.
+ break;
+ }
+ }
+
+ if (ret)
+ vgic_v4_teardown(kvm);
+
return ret;
}
void vgic_v4_teardown(struct kvm *kvm)
{
struct its_vm *its_vm = &kvm->arch.vgic.its_vm;
+ int i;
if (!its_vm->vpes)
return;
+ for (i = 0; i < its_vm->nr_vpes; i++) {
+ struct kvm_vcpu *vcpu = kvm_get_vcpu(kvm, i);
+ free_irq(its_vm->vpes[i]->irq, vcpu);
+ }
+
its_free_vcpu_irqs(its_vm);
kfree(its_vm->vpes);
its_vm->nr_vpes = 0;
--
2.11.0Thanks, -Christoffer