KVM: vmx: speed up TPR below threshold vmexits

Since we're already in VCPU context, all we have to do here is recompute
the PPR value.  That will in turn generate a KVM_REQ_EVENT if necessary.

Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 7e9ac46..6b1d3a7 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -595,6 +595,12 @@
 	}
 }
 
+void kvm_apic_update_ppr(struct kvm_vcpu *vcpu)
+{
+	apic_update_ppr(vcpu->arch.apic);
+}
+EXPORT_SYMBOL_GPL(kvm_apic_update_ppr);
+
 static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
 {
 	kvm_lapic_set_reg(apic, APIC_TASKPRI, tpr);