diff --git a/hypervisor/arch/x86/guest/vlapic.c b/hypervisor/arch/x86/guest/vlapic.c
index eab9a538c..2095a93c6 100644
--- a/hypervisor/arch/x86/guest/vlapic.c
+++ b/hypervisor/arch/x86/guest/vlapic.c
@@ -134,23 +134,6 @@ static uint16_t vm_apicid2vcpu_id(struct acrn_vm *vm, uint32_t lapicid)
 
 }
 
-/*
- * @pre vlapic != NULL
- */
-static uint64_t
-vm_active_cpus(const struct acrn_vm *vm)
-{
-	uint64_t dmask = 0UL;
-	uint16_t i;
-	const struct acrn_vcpu *vcpu;
-
-	foreach_vcpu(i, vm, vcpu) {
-		bitmap_set_nolock(vcpu->vcpu_id, &dmask);
-	}
-
-	return dmask;
-}
-
 /*
  * @pre vlapic != NULL
  */
diff --git a/hypervisor/include/arch/x86/guest/vm.h b/hypervisor/include/arch/x86/guest/vm.h
index c6054ad3b..5e9be235f 100644
--- a/hypervisor/include/arch/x86/guest/vm.h
+++ b/hypervisor/include/arch/x86/guest/vm.h
@@ -14,6 +14,7 @@
 #ifndef ASSEMBLER
 
 #include <types.h>
+#include <bits.h>
 #include <spinlock.h>
 #include <acrn_common.h>
 #include <bsp_extern.h>
@@ -211,6 +212,22 @@ struct acrn_vm_config {
 
 } __aligned(8);
 
+/*
+ * @pre vlapic != NULL
+ */
+static inline uint64_t vm_active_cpus(const struct acrn_vm *vm)
+{
+	uint64_t dmask = 0UL;
+	uint16_t i;
+	const struct acrn_vcpu *vcpu;
+
+	foreach_vcpu(i, vm, vcpu) {
+		bitmap_set_nolock(vcpu->vcpu_id, &dmask);
+	}
+
+	return dmask;
+}
+
 /*
  * @pre vcpu_id < CONFIG_MAX_VCPUS_PER_VM
  */