KVM: x86: Avoid double CPUID lookup when updating MWAIT at runtime

Move the handling of X86_FEATURE_MWAIT during CPUID runtime updates to
utilize the lookup done for other CPUID.0x1 features.

No functional change intended.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-46-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/kvm/cpuid.c

@@ -304,6 +304,11 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
 
 		cpuid_entry_change(best, X86_FEATURE_APIC,
 			   vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE);
+
+		if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT))
+			cpuid_entry_change(best, X86_FEATURE_MWAIT,
+					   vcpu->arch.ia32_misc_enable_msr &
+					   MSR_IA32_MISC_ENABLE_MWAIT);
 	}
 
 	best = kvm_find_cpuid_entry_index(vcpu, 7, 0);
@@ -319,14 +324,6 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
 	if (best && (cpuid_entry_has(best, X86_FEATURE_XSAVES) ||
 		     cpuid_entry_has(best, X86_FEATURE_XSAVEC)))
 		best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
-
-	if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) {
-		best = kvm_find_cpuid_entry(vcpu, 0x1);
-		if (best)
-			cpuid_entry_change(best, X86_FEATURE_MWAIT,
-					   vcpu->arch.ia32_misc_enable_msr &
-					   MSR_IA32_MISC_ENABLE_MWAIT);
-	}
 }
 EXPORT_SYMBOL_GPL(kvm_update_cpuid_runtime);