Windows Internals, Part 1: System architecture, processes, threads, memory management, and more, Seventh Edition

Applying boosts

Back in KiExitDispatcher, you saw that KiProcessThreadWaitList is called to process any threads in the deferred ready list. It is here that the boost information passed by the caller is processed. This is done by looping through each DeferredReady thread, unlinking its wait blocks (only Active and Bypassed blocks are unlinked), and setting two key values in the kernel’s thread control block: Adjust-Reason and AdjustIncrement. The reason is one of the two Adjust possibilities seen earlier, and the increment corresponds to the boost value. KiDeferredReadyThread is then called. This makes the thread ready for execution by running two algorithms: the quantum and priority selection algorithm (which you are about to see in two parts) ...