处理异步驱动程序通知

当操作系统调用已注册的回调函数时，它会将指针传递到 NotificationStructure 参数中的DEVICE_INTERFACE_CHANGE_NOTIFICATION结构。

下面的代码示例演示了一个回调函数的实现，该函数处理处理器的异步驱动程序通知：

// Asynchronous processor notification callback function
NTSTATUS
  AsyncProcessorCallback(
    IN PVOID NotificationStructure,
    IN PVOID Context
    )
{
  PDEVICE_INTERFACE_CHANGE_NOTIFICATION Notification;
  ULONG ProcessorCount;
  KAFFINITY ActiveProcessors;

  Notification = 
    (PDEVICE_INTERFACE_CHANGE_NOTIFICATION)
      NotificationStructure;

  // Verify that this notification is about a processor
  // that is being added to the hardware partition.
  if (IsEqualGUID(
        &Notification->Event,
        &GUID_DEVICE_INTERFACE_ARRIVAL
        ))
  {
    // Get the current processor count and affinity
    ProcessorCount =
      KeQueryActiveProcessorCount(
        &ActiveProcessors
        );

    // Adjust any resource allocations that are based
    // on the number of processors.
    ...

    // Adjust the assignment of resources that are
    // assigned to specific processors.
    ...

    // Begin scheduling any per processor threads
    // on the new processor.
    ...

    // Adjust the scheduling of DPCs and other threads
    ...

    // Adjust any load balancing algorithms
    ...
  }

  // Always return success status
 return STATUS_SUCCESS;
}

下面的代码示例演示回调函数的实现，该函数处理内存的异步驱动程序通知：

// Asynchronous memory notification callback function
NTSTATUS
  AsyncMemoryCallback(
    IN PVOID NotificationStructure,
    IN PVOID Context
    )
{
  PDEVICE_INTERFACE_CHANGE_NOTIFICATION Notification;

  Notification = 
    (PDEVICE_INTERFACE_CHANGE_NOTIFICATION)
      NotificationStructure;

  // Verify that this notification is about memory
  // that is being added to the hardware partition.
  if (IsEqualGUID(
        &Notification->Event,
        &GUID_DEVICE_INTERFACE_ARRIVAL
        ))
  {
    // Increase the size of any memory buffers
    // for optimal performance of the driver.
    ...
  }

  // Always return success status
  return STATUS_SUCCESS;
}