struct PPM_PERF_STATE

typedef struct 
{
     ULONG Frequency;
     ULONG Power;
     UCHAR PercentFrequency;
     UCHAR IncreaseLevel;
     UCHAR DecreaseLevel;
     UCHAR Type;
     UINT64 Control;
     UINT64 Status;
     ULONG TotalHitCount;
     ULONG DesiredCount;
} PPM_PERF_STATE, *PPPM_PERF_STATE;

Windows Vista Kernel Structures