KeQueryActiveProcessorAffinity

NTSTATUS __fastcall KeQueryActiveProcessorAffinity(INT64 a1){
  KeCopyAffinityEx((_KAFFINITY_EX *)a1, &KeActiveProcessors);
  return KeNumberProcessors_0;
}

Referenced by:

EtwpGetMicroarchitecturalPmcAffinity
PpmCheckInitProcessors
PpmInstallPlatformIdleStates
PpmRegisterPerfStates