kvm: x86: Move last_cpu into kvm_vcpu_arch as last_vmentry_cpu

Both the vcpu_vmx structure and the vcpu_svm structure have a
'last_cpu' field. Move the common field into the kvm_vcpu_arch
structure. For clarity, rename it to 'last_vmentry_cpu.'
Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Message-Id: <20200603235623.245638-6-jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -827,6 +827,9 @@ struct kvm_vcpu_arch {
 	/* Flush the L1 Data cache for L1TF mitigation on VMENTER */
 	bool l1tf_flush_l1d;
 
+	/* Host CPU on which VM-entry was most recently attempted */
+	unsigned int last_vmentry_cpu;
+
 	/* AMD MSRC001_0015 Hardware Configuration */
 	u64 msr_hwcr;
 };

arch/x86/kvm/svm/sev.c

@@ -1186,7 +1186,7 @@ void pre_sev_run(struct vcpu_svm *svm, int cpu)
 	 * 2) or this VMCB was executed on different host CPU in previous VMRUNs.
 	 */
 	if (sd->sev_vmcbs[asid] == svm->vmcb &&
-	    svm->last_cpu == cpu)
+	    svm->vcpu.arch.last_vmentry_cpu == cpu)
 		return;
 
 	sd->sev_vmcbs[asid] = svm->vmcb;

arch/x86/kvm/svm/svm.c

@@ -2947,7 +2947,7 @@ static int handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 		kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;
 		kvm_run->fail_entry.hardware_entry_failure_reason
 			= svm->vmcb->control.exit_code;
-		kvm_run->fail_entry.cpu = svm->last_cpu;
+		kvm_run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
 		dump_vmcb(vcpu);
 		return 0;
 	}
@@ -2973,7 +2973,7 @@ static int handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 			KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
 		vcpu->run->internal.ndata = 2;
 		vcpu->run->internal.data[0] = exit_code;
-		vcpu->run->internal.data[1] = svm->last_cpu;
+		vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
 		return 0;
 	}
 
@@ -3398,7 +3398,7 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
 	 */
 	x86_spec_ctrl_set_guest(svm->spec_ctrl, svm->virt_spec_ctrl);
 
-	svm->last_cpu = vcpu->cpu;
+	vcpu->arch.last_vmentry_cpu = vcpu->cpu;
 	__svm_vcpu_run(svm->vmcb_pa, (unsigned long *)&svm->vcpu.arch.regs);
 
 #ifdef CONFIG_X86_64

arch/x86/kvm/svm/svm.h

@@ -158,9 +158,6 @@ struct vcpu_svm {
 	 */
 	struct list_head ir_list;
 	spinlock_t ir_list_lock;
-
-	/* which host CPU was used for running this vcpu */
-	unsigned int last_cpu;
 };
 
 struct svm_cpu_data {

arch/x86/kvm/vmx/vmx.c

@@ -4785,7 +4785,7 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
 		vcpu->run->internal.data[0] = vect_info;
 		vcpu->run->internal.data[1] = intr_info;
 		vcpu->run->internal.data[2] = error_code;
-		vcpu->run->internal.data[3] = vmx->last_cpu;
+		vcpu->run->internal.data[3] = vcpu->arch.last_vmentry_cpu;
 		return 0;
 	}
 
@@ -6007,7 +6007,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
 		vcpu->run->fail_entry.hardware_entry_failure_reason
 			= exit_reason;
-		vcpu->run->fail_entry.cpu = vmx->last_cpu;
+		vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
 		return 0;
 	}
 
@@ -6016,7 +6016,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
 		vcpu->run->fail_entry.hardware_entry_failure_reason
 			= vmcs_read32(VM_INSTRUCTION_ERROR);
-		vcpu->run->fail_entry.cpu = vmx->last_cpu;
+		vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
 		return 0;
 	}
 
@@ -6044,7 +6044,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 				vmcs_read64(GUEST_PHYSICAL_ADDRESS);
 		}
 		vcpu->run->internal.data[vcpu->run->internal.ndata++] =
-			vmx->last_cpu;
+			vcpu->arch.last_vmentry_cpu;
 		return 0;
 	}
 
@@ -6102,7 +6102,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 			KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
 	vcpu->run->internal.ndata = 2;
 	vcpu->run->internal.data[0] = exit_reason;
-	vcpu->run->internal.data[1] = vmx->last_cpu;
+	vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
 	return 0;
 }
 
@@ -6740,7 +6740,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
 	if (vcpu->arch.cr2 != read_cr2())
 		write_cr2(vcpu->arch.cr2);
 
-	vmx->last_cpu = vcpu->cpu;
+	vcpu->arch.last_vmentry_cpu = vcpu->cpu;
 	vmx->fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs,
 				   vmx->loaded_vmcs->launched);
 

arch/x86/kvm/vmx/vmx.h

@@ -300,9 +300,6 @@ struct vcpu_vmx {
 	u64 ept_pointer;
 
 	struct pt_desc pt_desc;
-
-	/* which host CPU was used for running this vcpu */
-	unsigned int last_cpu;
 };
 
 enum ept_pointers_status {