add hypercall hc_sos_offline_cpu support

SOS boot with all physicall cpus, before running UOS, it should free
CPU resource by offline not used cpus
- first do standard cpu offline flow
- then call hcall_sos_offline_cpu hypercall to release cpu resource really

Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

Author: JasonChenCJ

hypervisor/arch/x86/guest/vmcall.c

@@ -38,6 +38,9 @@ int vmcall_vmexit_handler(struct vcpu *vcpu)
 
 	/* Dispatch the hypercall handler */
 	switch (hypcall_id) {
+	case HC_SOS_OFFLINE_CPU:
+		ret = hcall_sos_offline_cpu(vm, param1);
+		break;
 	case HC_GET_API_VERSION:
 #ifdef CONFIG_VM0_DESC
 		/* vm0 will call HC_GET_API_VERSION as first hypercall, fixup

hypervisor/common/hypercall.c

@@ -25,6 +25,30 @@ bool is_hypercall_from_ring0(void)
 	return false;
 }
 
+int32_t hcall_sos_offline_cpu(struct vm *vm, uint64_t lapicid)
+{
+	struct vcpu *vcpu;
+	int i;
+
+	if (!is_vm0(vm))
+		return -1;
+
+	pr_info("sos offline cpu with lapicid %lld", lapicid);
+
+	foreach_vcpu(i, vm, vcpu) {
+		if (vlapic_get_apicid(vcpu->arch_vcpu.vlapic) == lapicid) {
+			/* should not offline BSP */
+			if (vcpu->vcpu_id == 0)
+				return -1;
+			pause_vcpu(vcpu, VCPU_ZOMBIE);
+			reset_vcpu(vcpu);
+			destroy_vcpu(vcpu);
+		}
+	}
+
+	return 0;
+}
+
 int32_t hcall_get_api_version(struct vm *vm, uint64_t param)
 {
 	struct hc_api_version version;

hypervisor/include/common/hypercall.h

@@ -24,6 +24,18 @@ bool is_hypercall_from_ring0(void);
  * @{
  */
 
+/**
+ * @brief offline vcpu from SOS
+ *
+ * The function offline specific vcpu from SOS.
+ *
+ * @param vm Pointer to VM data structure
+ * @param lapicid lapic id of the vcpu which wants to offline
+ *
+ * @return 0 on success, non-zero on error.
+ */
+int32_t hcall_sos_offline_cpu(struct vm *vm, uint64_t lapicid);
+
 /**
  * @brief Get hypervisor api version
  *

hypervisor/include/public/acrn_hv_defs.h

@@ -26,6 +26,7 @@
 /* general */
 #define HC_ID_GEN_BASE               0x0UL
 #define HC_GET_API_VERSION          _HC_ID(HC_ID, HC_ID_GEN_BASE + 0x00UL)
+#define HC_SOS_OFFLINE_CPU          _HC_ID(HC_ID, HC_ID_GEN_BASE + 0x01UL)
 
 /* VM management */
 #define HC_ID_VM_BASE               0x10UL