typedef struct _ERESOURCE
{
     LIST_ENTRY SystemResourcesList;
     POWNER_ENTRY OwnerTable;
     SHORT ActiveCount;
     WORD Flag;
     PKSEMAPHORE SharedWaiters;
     PKEVENT ExclusiveWaiters;
     OWNER_ENTRY OwnerEntry;
     ULONG ActiveEntries;
     ULONG ContentionCount;
     ULONG NumberOfSharedWaiters;
     ULONG NumberOfExclusiveWaiters;
     union
     {
          PVOID Address;
          ULONG CreatorBackTraceIndex;
     };
     ULONG SpinLock;
} ERESOURCE, *PERESOURCE;

Windows Vista Kernel Structures