KVM: VMX: Add the deliver posted interrupt algorithm
Only deliver the posted interrupt when target vcpu is running
and there is no previous interrupt pending in pir.
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 8535519..3a14d8a 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -375,6 +375,23 @@
u32 rsvd[7];
} __aligned(64);
+static bool pi_test_and_set_on(struct pi_desc *pi_desc)
+{
+ return test_and_set_bit(POSTED_INTR_ON,
+ (unsigned long *)&pi_desc->control);
+}
+
+static bool pi_test_and_clear_on(struct pi_desc *pi_desc)
+{
+ return test_and_clear_bit(POSTED_INTR_ON,
+ (unsigned long *)&pi_desc->control);
+}
+
+static int pi_test_and_set_pir(int vector, struct pi_desc *pi_desc)
+{
+ return test_and_set_bit(vector, (unsigned long *)pi_desc->pir);
+}
+
struct vcpu_vmx {
struct kvm_vcpu vcpu;
unsigned long host_rsp;
@@ -639,6 +656,7 @@
struct kvm_segment *var, int seg);
static bool guest_state_valid(struct kvm_vcpu *vcpu);
static u32 vmx_segment_access_rights(struct kvm_segment *var);
+static void vmx_sync_pir_to_irr_dummy(struct kvm_vcpu *vcpu);
static DEFINE_PER_CPU(struct vmcs *, vmxarea);
static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
@@ -2846,8 +2864,11 @@
if (enable_apicv)
kvm_x86_ops->update_cr8_intercept = NULL;
- else
+ else {
kvm_x86_ops->hwapic_irr_update = NULL;
+ kvm_x86_ops->deliver_posted_interrupt = NULL;
+ kvm_x86_ops->sync_pir_to_irr = vmx_sync_pir_to_irr_dummy;
+ }
if (nested)
nested_vmx_setup_ctls_msrs();
@@ -3909,6 +3930,45 @@
}
/*
+ * Send interrupt to vcpu via posted interrupt way.
+ * 1. If target vcpu is running(non-root mode), send posted interrupt
+ * notification to vcpu and hardware will sync PIR to vIRR atomically.
+ * 2. If target vcpu isn't running(root mode), kick it to pick up the
+ * interrupt from PIR in next vmentry.
+ */
+static void vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
+{
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
+ int r;
+
+ if (pi_test_and_set_pir(vector, &vmx->pi_desc))
+ return;
+
+ r = pi_test_and_set_on(&vmx->pi_desc);
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+ if (!r && (vcpu->mode == IN_GUEST_MODE))
+ apic->send_IPI_mask(get_cpu_mask(vcpu->cpu),
+ POSTED_INTR_VECTOR);
+ else
+ kvm_vcpu_kick(vcpu);
+}
+
+static void vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+ if (!pi_test_and_clear_on(&vmx->pi_desc))
+ return;
+
+ kvm_apic_update_irr(vcpu, vmx->pi_desc.pir);
+}
+
+static void vmx_sync_pir_to_irr_dummy(struct kvm_vcpu *vcpu)
+{
+ return;
+}
+
+/*
* Set up the vmcs's constant host-state fields, i.e., host-state fields that
* will not change in the lifetime of the guest.
* Note that host-state that does change is set elsewhere. E.g., host-state
@@ -7784,6 +7844,8 @@
.load_eoi_exitmap = vmx_load_eoi_exitmap,
.hwapic_irr_update = vmx_hwapic_irr_update,
.hwapic_isr_update = vmx_hwapic_isr_update,
+ .sync_pir_to_irr = vmx_sync_pir_to_irr,
+ .deliver_posted_interrupt = vmx_deliver_posted_interrupt,
.set_tss_addr = vmx_set_tss_addr,
.get_tdp_level = get_ept_level,
