static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	int r;

	r = vmx_deliver_nested_posted_interrupt(vcpu, vector);
	if (!r)
		return 0;

	if (!vcpu->arch.apicv_active)
		return -1;

	if (pi_test_and_set_pir(vector, &vmx->pi_desc))
		return 0;

	/* If a previous notification has sent the IPI, nothing to do.  */
	if (pi_test_and_set_on(&vmx->pi_desc))
		return 0;

	/*
	 * The implied barrier in pi_test_and_set_on() pairs with the smp_mb_*()
	 * after setting vcpu->mode in vcpu_enter_guest(), thus the vCPU is
	 * guaranteed to see PID.ON=1 and sync the PIR to IRR if triggering a
	 * posted interrupt "fails" because vcpu->mode != IN_GUEST_MODE.
	 */
	kvm_vcpu_trigger_posted_interrupt(vcpu, POSTED_INTR_VECTOR);
	return 0;
}
static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	int r;

	r = vmx_deliver_nested_posted_interrupt(vcpu, vector);
	if (!r)
		return 0;

	if (!vcpu->arch.apicv_active)
		return -1;

	if (pi_test_and_set_pir(vector, &vmx->pi_desc))
		return 0;

	 
	if (pi_test_and_set_on(&vmx->pi_desc))
		return 0;

	 
	kvm_vcpu_trigger_posted_interrupt(vcpu, POSTED_INTR_VECTOR);
	return 0;
}