{
    PKDPC_DATA DpcData;
    PLIST_ENTRY ListHead, DpcEntry;
    PKDPC Dpc;
    PKDEFERRED_ROUTINE DeferredRoutine;
    PVOID DeferredContext, SystemArgument1, SystemArgument2;
    ULONG_PTR TimerHand;
#ifdef CONFIG_SMP
    KIRQL OldIrql;
#endif

    /* Get data and list variables before starting anything else */
    DpcData = &Prcb->DpcData[DPC_NORMAL];
    ListHead = &DpcData->DpcListHead;

    /* Main outer loop */
    do
    {
        /* Set us as active */
        Prcb->DpcRoutineActive = TRUE;

        /* Check if this is a timer expiration request */
        if (Prcb->TimerRequest)
        {
            /* It is, get the timer hand and disable timer request */
            TimerHand = Prcb->TimerHand;
            Prcb->TimerRequest = 0;

            /* Expire timers with interrups enabled */
            _enable();
            KiTimerExpiration(NULL, NULL, (PVOID)TimerHand, NULL);
            _disable();
        }

        /* Loop while we have entries in the queue */
        while (DpcData->DpcQueueDepth != 0)
        {
            /* Lock the DPC data and get the DPC entry*/
            KeAcquireSpinLockAtDpcLevel(&DpcData->DpcLock);
            DpcEntry = ListHead->Flink;

            /* Make sure we have an entry */
            if (DpcEntry != ListHead)
            {
                /* Remove the DPC from the list */
                RemoveEntryList(DpcEntry);
                Dpc = CONTAINING_RECORD(DpcEntry, KDPC, DpcListEntry);

                /* Clear its DPC data and save its parameters */
                Dpc->DpcData = NULL;
                DeferredRoutine = Dpc->DeferredRoutine;
                DeferredContext = Dpc->DeferredContext;
                SystemArgument1 = Dpc->SystemArgument1;
                SystemArgument2 = Dpc->SystemArgument2;

                /* Decrease the queue depth */
                DpcData->DpcQueueDepth--;

                /* Clear DPC Time */
                Prcb->DebugDpcTime = 0;

                /* Release the lock */
                KeReleaseSpinLockFromDpcLevel(&DpcData->DpcLock);

                /* Re-enable interrupts */
                _enable();

                /* Call the DPC */
                DeferredRoutine(Dpc,
                                DeferredContext,
                                SystemArgument1,
                                SystemArgument2);
                ASSERT(KeGetCurrentIrql() == DISPATCH_LEVEL);

                /* Disable interrupts and keep looping */
                _disable();
            }
            else
            {
                /* The queue should be flushed now */
                ASSERT(DpcData->DpcQueueDepth == 0);

                /* Release DPC Lock */
                KeReleaseSpinLockFromDpcLevel(&DpcData->DpcLock);
            }
        }

        /* Clear DPC Flags */
        Prcb->DpcRoutineActive = FALSE;
        Prcb->DpcInterruptRequested = FALSE;

#ifdef CONFIG_SMP
        /* Check if we have deferred threads */
        if (Prcb->DeferredReadyListHead.Next)
        {

            /* Re-enable interrupts and raise to synch */
            _enable();
            OldIrql = KeRaiseIrqlToSynchLevel();

            /* Process deferred threads */
            KiProcessDeferredReadyList(Prcb);

            /* Lower IRQL back and disable interrupts */
            KeLowerIrql(OldIrql);
            _disable();
        }
#endif
    } while (DpcData->DpcQueueDepth != 0);
}

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