ke_x.h

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    ASSERT(KeGetCurrentIrql() >= DISPATCH_LEVEL);

    /* Nothing to do on UP */
    UNREFERENCED_PARAMETER(LockQueue);
}

#else

//
// Spinlock Acquisition at IRQL >= DISPATCH_LEVEL
//
FORCEINLINE
VOID
KxAcquireSpinLock(IN PKSPIN_LOCK SpinLock)
{
    for (;;)
    {
        /* Try to acquire it */
        if (InterlockedBitTestAndSet((PLONG)SpinLock, 0))
        {
            /* Value changed... wait until it's locked */
            while (*(volatile KSPIN_LOCK *)SpinLock == 1)
            {
#ifdef DBG
                /* On debug builds, we use a much slower but useful routine */
                Kii386SpinOnSpinLock(SpinLock, 5);
#else
                /* Otherwise, just yield and keep looping */
                YieldProcessor();
#endif
            }
        }
        else
        {
#ifdef DBG
            /* On debug builds, we OR in the KTHREAD */
            *SpinLock = KeGetCurrentThread() | 1;
#endif
            /* All is well, break out */
            break;
        }
    }
}

//
// Spinlock Release at IRQL >= DISPATCH_LEVEL
//
FORCEINLINE
VOID
KxReleaseSpinLock(IN PKSPIN_LOCK SpinLock)
{
#ifdef DBG
    /* Make sure that the threads match */
    if ((KeGetCurrentThread() | 1) != *SpinLock)
    {
        /* They don't, bugcheck */
        KeBugCheckEx(SPIN_LOCK_NOT_OWNED, SpinLock, 0, 0, 0);
    }
#endif
    /* Clear the lock */
    InterlockedAnd(SpinLock, 0);
}

KIRQL
FORCEINLINE
KiAcquireDispatcherObject(IN DISPATCHER_HEADER* Object)
{
    LONG OldValue, NewValue;

    /* Make sure we're at a safe level to touch the lock */
    ASSERT(KeGetCurrentIrql() >= DISPATCH_LEVEL);

    /* Start acquire loop */
    do
    {
        /* Loop until the other CPU releases it */
        while ((UCHAR)Object->Lock & KOBJECT_LOCK_BIT)
        {
            /* Let the CPU know that this is a loop */
            YieldProcessor();
        };

        /* Try acquiring the lock now */
        NewValue = InterlockedCompareExchange(&Object->Lock,
                                              OldValue | KOBJECT_LOCK_BIT,
                                              OldValue);
    } while (NewValue != OldValue);
}

KIRQL
FORCEINLINE
KiReleaseDispatcherObject(IN DISPATCHER_HEADER* Object)
{
    /* Make sure we're at a safe level to touch the lock */
    ASSERT(KeGetCurrentIrql() >= DISPATCH_LEVEL);

    /* Release it */
    InterlockedAnd(&Object->Lock, ~KOBJECT_LOCK_BIT);
}

KIRQL
FORCEINLINE
KiAcquireDispatcherLock(VOID)
{
    /* Raise to synchronization level and acquire the dispatcher lock */
    return KeAcquireQueuedSpinLockRaiseToSynch(LockQueueDispatcherLock);
}

VOID
FORCEINLINE
KiReleaseDispatcherLock(IN KIRQL OldIrql)
{
    /* First release the lock */
    KeReleaseQueuedSpinLockFromDpcLevel(&KeGetCurrentPrcb()->
                                        LockQueue[LockQueueDispatcherLock]);

    /* Then exit the dispatcher */
    KiExitDispatcher(OldIrql);
}

//
// This routine inserts a thread into the deferred ready list of the given CPU
//
FORCEINLINE
VOID
KiInsertDeferredReadyList(IN PKTHREAD Thread)
{
    PKPRCB Prcb = KeGetCurrentPrcb();

    /* Set the thread to deferred state and CPU */
    Thread->State = DeferredReady;
    Thread->DeferredProcessor = Prcb->Number;

    /* Add it on the list */
    PushEntryList(&Prcb->DeferredReadyListHead, &Thread->SwapListEntry);
}

FORCEINLINE
VOID
KiRescheduleThread(IN BOOLEAN NewThread,
                   IN ULONG Cpu)
{
    /* Check if a new thread needs to be scheduled on a different CPU */
    if ((NewThread) && !(KeGetPcr()->Number == Cpu))
    {
        /* Send an IPI to request delivery */
        KiIpiSendRequest(AFFINITY_MASK(Cpu), IPI_DPC);
    }
}

//
// This routine sets the current thread in a swap busy state, which ensure that
// nobody else tries to swap it concurrently.
//
FORCEINLINE
VOID
KiSetThreadSwapBusy(IN PKTHREAD Thread)
{
    /* Make sure nobody already set it */
    ASSERT(Thread->SwapBusy == FALSE);

    /* Set it ourselves */
    Thread->SwapBusy = TRUE;
}

//
// This routine acquires the PRCB lock so that only one caller can touch
// volatile PRCB data.
//
// Since this is a simple optimized spin-lock, it must be be only acquired
// at dispatcher level or higher!
//
FORCEINLINE
VOID
KiAcquirePrcbLock(IN PKPRCB Prcb)
{
    /* Make sure we're at a safe level to touch the PRCB lock */
    ASSERT(KeGetCurrentIrql() >= DISPATCH_LEVEL);

    /* Start acquire loop */
    for (;;)
    {
        /* Acquire the lock and break out if we acquired it first */
        if (!InterlockedExchange(&Prcb->PrcbLock, 1)) break;

        /* Loop until the other CPU releases it */
        do
        {
            /* Let the CPU know that this is a loop */
            YieldProcessor();
        } while (Prcb->PrcbLock);
    }
}

//
// This routine releases the PRCB lock so that other callers can touch
// volatile PRCB data.
//
// Since this is a simple optimized spin-lock, it must be be only acquired
// at dispatcher level or higher!
//
FORCEINLINE
VOID
KiReleasePrcbLock(IN PKPRCB Prcb)
{
    /* Make sure it's acquired! */
    ASSERT(Prcb->PrcbLock != 0);

    /* Release it */
    InterlockedAnd(&Prcb->PrcbLock, 0);
}

//
// This routine acquires the thread lock so that only one caller can touch
// volatile thread data.
//
// Since this is a simple optimized spin-lock, it must be be only acquired
// at dispatcher level or higher!
//
FORCEINLINE
VOID
KiAcquireThreadLock(IN PKTHREAD Thread)
{
    /* Make sure we're at a safe level to touch the thread lock */
    ASSERT(KeGetCurrentIrql() >= DISPATCH_LEVEL);

    /* Start acquire loop */
    for (;;)
    {
        /* Acquire the lock and break out if we acquired it first */
        if (!InterlockedExchange(&Thread->ThreadLock, 1)) break;

        /* Loop until the other CPU releases it */
        do
        {
            /* Let the CPU know that this is a loop */
            YieldProcessor();
        } while (Thread->ThreadLock);
    }
}

//
// This routine releases the thread lock so that other callers can touch
// volatile thread data.
//
// Since this is a simple optimized spin-lock, it must be be only acquired
// at dispatcher level or higher!
//
FORCEINLINE
VOID
KiReleaseThreadLock(IN PKTHREAD Thread)
{
    /* Release it */
    InterlockedAnd(&Thread->ThreadLock, 0);
}

FORCEINLINE
BOOLEAN
KiTryThreadLock(IN PKTHREAD Thread)
{
    LONG Value;

    /* If the lock isn't acquired, return false */
    if (!Thread->ThreadLock) return FALSE;

    /* Otherwise, try to acquire it and check the result */
    Value = 1;
    Value = InterlockedExchange(&Thread->ThreadLock, &Value);

    /* Return the lock state */
    return (Value == TRUE);
}

FORCEINLINE
VOID
KiCheckDeferredReadyList(IN PKPRCB Prcb)
{
    /* Scan the deferred ready lists if required */
    if (Prcb->DeferredReadyListHead.Next) KiProcessDeferredReadyList(Prcb);
}

FORCEINLINE
VOID
KiRequestApcInterrupt(IN BOOLEAN NeedApc,
                      IN UCHAR Processor)
{
    /* Check if we need to request APC delivery */
    if (NeedApc)
    {
        /* Check if it's on another CPU */
        if (KeGetPcr()->Number != Cpu)
        {
            /* Send an IPI to request delivery */
            KiIpiSendRequest(AFFINITY_MASK(Cpu), IPI_DPC);
        }
        else
        {
            /* Request a software interrupt */
            HalRequestSoftwareInterrupt(APC_LEVEL);
        }
    }
}

#endif

FORCEINLINE
VOID
KiAcquireApcLock(IN PKTHREAD Thread,
                 IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Acquire the lock and raise to synchronization level */
    KeAcquireInStackQueuedSpinLockRaiseToSynch(&Thread->ApcQueueLock, Handle);
}

FORCEINLINE
VOID
KiAcquireApcLockAtDpcLevel(IN PKTHREAD Thread,
                           IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Acquire the lock */
    KeAcquireInStackQueuedSpinLockAtDpcLevel(&Thread->ApcQueueLock, Handle);
}

FORCEINLINE
VOID
KiAcquireApcLockAtApcLevel(IN PKTHREAD Thread,
                           IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Acquire the lock */
    KeAcquireInStackQueuedSpinLock(&Thread->ApcQueueLock, Handle);
}

FORCEINLINE
VOID
KiReleaseApcLock(IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Release the lock */
    KeReleaseInStackQueuedSpinLock(Handle);
}

FORCEINLINE
VOID
KiReleaseApcLockFromDpcLevel(IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Release the lock */
    KeReleaseInStackQueuedSpinLockFromDpcLevel(Handle);
}

FORCEINLINE
VOID
KiAcquireProcessLock(IN PKPROCESS Process,
                     IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Acquire the lock and raise to synchronization level */
    KeAcquireInStackQueuedSpinLockRaiseToSynch(&Process->ProcessLock, Handle);
}

FORCEINLINE
VOID
KiReleaseProcessLock(IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Release the lock */
    KeReleaseInStackQueuedSpinLock(Handle);
}

FORCEINLINE
VOID
KiReleaseProcessLockFromDpcLevel(IN PKLOCK_QUEUE_HANDLE Handle)
{
    /* Release the lock */
    KeReleaseInStackQueuedSpinLockFromDpcLevel(Handle);
}

FORCEINLINE
VOID
KiAcquireDeviceQueueLock(IN PKDEVICE_QUEUE DeviceQueue,
                         IN PKLOCK_QUEUE_HANDLE DeviceLock)
{
    /* Check if we were called from a threaded DPC */
    if (KeGetCurrentPrcb()->DpcThreadActive)
    {
        /* Lock the Queue, we're not at DPC level */
        KeAcquireInStackQueuedSpinLock(&DeviceQueue->Lock, DeviceLock);
    }
    else
    {