typedef enum _ARBITER_ACTION
{
         ArbiterActionTestAllocation = 0,
         ArbiterActionRetestAllocation = 1,
         ArbiterActionCommitAllocation = 2,
         ArbiterActionRollbackAllocation = 3,
         ArbiterActionQueryAllocatedResources = 4,
         ArbiterActionWriteReservedResources = 5,
         ArbiterActionQueryConflict = 6,
         ArbiterActionQueryArbitrate = 7,
         ArbiterActionAddReserved = 8,
         ArbiterActionBootAllocation = 9
} ARBITER_ACTION;

Windows Vista Kernel Structures