KVM: VMX: Introduce pi_is_pir_empty() helper

Streamline the PID.PIR check and change its call sites to use
the newly added helper.
Suggested-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/vmx.c

@@ -1305,7 +1305,7 @@ static void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu)
 	 */
 	smp_mb__after_atomic();
 
-	if (!bitmap_empty((unsigned long *)pi_desc->pir, NR_VECTORS))
+	if (!pi_is_pir_empty(pi_desc))
 		pi_set_on(pi_desc);
 }
 
@@ -6184,8 +6184,7 @@ static bool vmx_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu)
 	struct pi_desc *pi_desc = vcpu_to_pi_desc(vcpu);
 
 	return pi_test_on(pi_desc) ||
-		(pi_test_sn(pi_desc) &&
-		!bitmap_empty((unsigned long *)pi_desc->pir, NR_VECTORS));
+		(pi_test_sn(pi_desc) && !pi_is_pir_empty(pi_desc));
 }
 
 static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)

arch/x86/kvm/vmx/vmx.h

@@ -355,6 +355,11 @@ static inline int pi_test_and_set_pir(int vector, struct pi_desc *pi_desc)
 	return test_and_set_bit(vector, (unsigned long *)pi_desc->pir);
 }
 
+static inline bool pi_is_pir_empty(struct pi_desc *pi_desc)
+{
+	return bitmap_empty((unsigned long *)pi_desc->pir, NR_VECTORS);
+}
+
 static inline void pi_set_sn(struct pi_desc *pi_desc)
 {
 	set_bit(POSTED_INTR_SN,