typedef struct _INTERLOCK_SEQ
{
    union
    {
        struct
        {
            unsigned short Depth;
            unsigned short FreeEntryOffset;
        };
        struct
        {
            volatile unsigned long OffsetAndDepth;
            volatile unsigned long Sequence;
        };
        volatile __int64 Exchg;
    };
} INTERLOCK_SEQ, *PINTERLOCK_SEQ;