MdeModulePkg: document workaround for EFI_RUNTIME_EVENT_ENTRY PI spec bug

[mirror_edk2.git] / MdeModulePkg / Core / Dxe / Event / Event.c

/** @file\r
  UEFI Event support functions implemented in this file.\r
\r
Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>\r
(C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
\r
#include "DxeMain.h"\r
#include "Event.h"\r
\r
///\r
/// gEfiCurrentTpl - Current Task priority level\r
///\r
EFI_TPL  gEfiCurrentTpl = TPL_APPLICATION;\r
\r
///\r
/// gEventQueueLock - Protects the event queues\r
///\r
EFI_LOCK gEventQueueLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_HIGH_LEVEL);\r
\r
///\r
/// gEventQueue - A list of event's to notify for each priority level\r
///\r
LIST_ENTRY      gEventQueue[TPL_HIGH_LEVEL + 1];\r
\r
///\r
/// gEventPending - A bitmask of the EventQueues that are pending\r
///\r
UINTN           gEventPending = 0;\r
\r
///\r
/// gEventSignalQueue - A list of events to signal based on EventGroup type\r
///\r
LIST_ENTRY      gEventSignalQueue = INITIALIZE_LIST_HEAD_VARIABLE (gEventSignalQueue);\r
\r
///\r
/// Enumerate the valid types\r
///\r
UINT32 mEventTable[] = {\r
  ///\r
  /// 0x80000200       Timer event with a notification function that is\r
  /// queue when the event is signaled with SignalEvent()\r
  ///\r
  EVT_TIMER | EVT_NOTIFY_SIGNAL,\r
  ///\r
  /// 0x80000000       Timer event without a notification function. It can be\r
  /// signaled with SignalEvent() and checked with CheckEvent() or WaitForEvent().\r
  ///\r
  EVT_TIMER,\r
  ///\r
  /// 0x00000100       Generic event with a notification function that\r
  /// can be waited on with CheckEvent() or WaitForEvent()\r
  ///\r
  EVT_NOTIFY_WAIT,\r
  ///\r
  /// 0x00000200       Generic event with a notification function that\r
  /// is queue when the event is signaled with SignalEvent()\r
  ///\r
  EVT_NOTIFY_SIGNAL,\r
  ///\r
  /// 0x00000201       ExitBootServicesEvent.\r
  ///\r
  EVT_SIGNAL_EXIT_BOOT_SERVICES,\r
  ///\r
  /// 0x60000202       SetVirtualAddressMapEvent.\r
  ///\r
  EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE,\r
\r
  ///\r
  /// 0x00000000       Generic event without a notification function.\r
  /// It can be signaled with SignalEvent() and checked with CheckEvent()\r
  /// or WaitForEvent().\r
  ///\r
  0x00000000,\r
  ///\r
  /// 0x80000100       Timer event with a notification function that can be\r
  /// waited on with CheckEvent() or WaitForEvent()\r
  ///\r
  EVT_TIMER | EVT_NOTIFY_WAIT,\r
};\r
\r
///\r
/// gIdleLoopEvent - Event which is signalled when the core is idle\r
///\r
EFI_EVENT       gIdleLoopEvent = NULL;\r
\r
\r
/**\r
  Enter critical section by acquiring the lock on gEventQueueLock.\r
\r
**/\r
VOID\r
CoreAcquireEventLock (\r
  VOID\r
  )\r
{\r
  CoreAcquireLock (&gEventQueueLock);\r
}\r
\r
\r
/**\r
  Exit critical section by releasing the lock on gEventQueueLock.\r
\r
**/\r
VOID\r
CoreReleaseEventLock (\r
  VOID\r
  )\r
{\r
  CoreReleaseLock (&gEventQueueLock);\r
}\r
\r
\r
\r
/**\r
  Initializes "event" support.\r
\r
  @retval EFI_SUCCESS            Always return success\r
\r
**/\r
EFI_STATUS\r
CoreInitializeEventServices (\r
  VOID\r
  )\r
{\r
  UINTN        Index;\r
\r
  for (Index=0; Index <= TPL_HIGH_LEVEL; Index++) {\r
    InitializeListHead (&gEventQueue[Index]);\r
  }\r
\r
  CoreInitializeTimer ();\r
\r
  CoreCreateEventEx (\r
    EVT_NOTIFY_SIGNAL,\r
    TPL_NOTIFY,\r
    EfiEventEmptyFunction,\r
    NULL,\r
    &gIdleLoopEventGuid,\r
    &gIdleLoopEvent\r
    );\r
\r
  return EFI_SUCCESS;\r
}\r
\r
\r
\r
/**\r
  Dispatches all pending events.\r
\r
  @param  Priority               The task priority level of event notifications\r
                                 to dispatch\r
\r
**/\r
VOID\r
CoreDispatchEventNotifies (\r
  IN EFI_TPL      Priority\r
  )\r
{\r
  IEVENT          *Event;\r
  LIST_ENTRY      *Head;\r
\r
  CoreAcquireEventLock ();\r
  ASSERT (gEventQueueLock.OwnerTpl == Priority);\r
  Head = &gEventQueue[Priority];\r
\r
  //\r
  // Dispatch all the pending notifications\r
  //\r
  while (!IsListEmpty (Head)) {\r
\r
    Event = CR (Head->ForwardLink, IEVENT, NotifyLink, EVENT_SIGNATURE);\r
    RemoveEntryList (&Event->NotifyLink);\r
\r
    Event->NotifyLink.ForwardLink = NULL;\r
\r
    //\r
    // Only clear the SIGNAL status if it is a SIGNAL type event.\r
    // WAIT type events are only cleared in CheckEvent()\r
    //\r
    if ((Event->Type & EVT_NOTIFY_SIGNAL) != 0) {\r
      Event->SignalCount = 0;\r
    }\r
\r
    CoreReleaseEventLock ();\r
\r
    //\r
    // Notify this event\r
    //\r
    ASSERT (Event->NotifyFunction != NULL);\r
    Event->NotifyFunction (Event, Event->NotifyContext);\r
\r
    //\r
    // Check for next pending event\r
    //\r
    CoreAcquireEventLock ();\r
  }\r
\r
  gEventPending &= ~(UINTN)(1 << Priority);\r
  CoreReleaseEventLock ();\r
}\r
\r
\r
\r
/**\r
  Queues the event's notification function to fire.\r
\r
  @param  Event                  The Event to notify\r
\r
**/\r
VOID\r
CoreNotifyEvent (\r
  IN  IEVENT      *Event\r
  )\r
{\r
\r
  //\r
  // Event database must be locked\r
  //\r
  ASSERT_LOCKED (&gEventQueueLock);\r
\r
  //\r
  // If the event is queued somewhere, remove it\r
  //\r
\r
  if (Event->NotifyLink.ForwardLink != NULL) {\r
    RemoveEntryList (&Event->NotifyLink);\r
    Event->NotifyLink.ForwardLink = NULL;\r
  }\r
\r
  //\r
  // Queue the event to the pending notification list\r
  //\r
\r
  InsertTailList (&gEventQueue[Event->NotifyTpl], &Event->NotifyLink);\r
  gEventPending |= (UINTN)(1 << Event->NotifyTpl);\r
}\r
\r
\r
\r
\r
/**\r
  Signals all events in the EventGroup.\r
\r
  @param  EventGroup             The list to signal\r
\r
**/\r
VOID\r
CoreNotifySignalList (\r
  IN EFI_GUID     *EventGroup\r
  )\r
{\r
  LIST_ENTRY              *Link;\r
  LIST_ENTRY              *Head;\r
  IEVENT                  *Event;\r
\r
  CoreAcquireEventLock ();\r
\r
  Head = &gEventSignalQueue;\r
  for (Link = Head->ForwardLink; Link != Head; Link = Link->ForwardLink) {\r
    Event = CR (Link, IEVENT, SignalLink, EVENT_SIGNATURE);\r
    if (CompareGuid (&Event->EventGroup, EventGroup)) {\r
      CoreNotifyEvent (Event);\r
    }\r
  }\r
\r
  CoreReleaseEventLock ();\r
}\r
\r
\r
/**\r
  Creates an event.\r
\r
  @param  Type                   The type of event to create and its mode and\r
                                 attributes\r
  @param  NotifyTpl              The task priority level of event notifications\r
  @param  NotifyFunction         Pointer to the events notification function\r
  @param  NotifyContext          Pointer to the notification functions context;\r
                                 corresponds to parameter "Context" in the\r
                                 notification function\r
  @param  Event                  Pointer to the newly created event if the call\r
                                 succeeds; undefined otherwise\r
\r
  @retval EFI_SUCCESS            The event structure was created\r
  @retval EFI_INVALID_PARAMETER  One of the parameters has an invalid value\r
  @retval EFI_OUT_OF_RESOURCES   The event could not be allocated\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreCreateEvent (\r
  IN UINT32                   Type,\r
  IN EFI_TPL                  NotifyTpl,\r
  IN EFI_EVENT_NOTIFY         NotifyFunction, OPTIONAL\r
  IN VOID                     *NotifyContext, OPTIONAL\r
  OUT EFI_EVENT               *Event\r
  )\r
{\r
  return CoreCreateEventEx (Type, NotifyTpl, NotifyFunction, NotifyContext, NULL, Event);\r
}\r
\r
\r
\r
/**\r
  Creates an event in a group.\r
\r
  @param  Type                   The type of event to create and its mode and\r
                                 attributes\r
  @param  NotifyTpl              The task priority level of event notifications\r
  @param  NotifyFunction         Pointer to the events notification function\r
  @param  NotifyContext          Pointer to the notification functions context;\r
                                 corresponds to parameter "Context" in the\r
                                 notification function\r
  @param  EventGroup             GUID for EventGroup if NULL act the same as\r
                                 gBS->CreateEvent().\r
  @param  Event                  Pointer to the newly created event if the call\r
                                 succeeds; undefined otherwise\r
\r
  @retval EFI_SUCCESS            The event structure was created\r
  @retval EFI_INVALID_PARAMETER  One of the parameters has an invalid value\r
  @retval EFI_OUT_OF_RESOURCES   The event could not be allocated\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreCreateEventEx (\r
  IN UINT32                   Type,\r
  IN EFI_TPL                  NotifyTpl,\r
  IN EFI_EVENT_NOTIFY         NotifyFunction, OPTIONAL\r
  IN CONST VOID               *NotifyContext, OPTIONAL\r
  IN CONST EFI_GUID           *EventGroup,    OPTIONAL\r
  OUT EFI_EVENT               *Event\r
  )\r
{\r
  //\r
  // If it's a notify type of event, check for invalid NotifyTpl\r
  //\r
  if ((Type & (EVT_NOTIFY_WAIT | EVT_NOTIFY_SIGNAL)) != 0) {\r
    if (NotifyTpl != TPL_APPLICATION &&\r
        NotifyTpl != TPL_CALLBACK &&\r
        NotifyTpl != TPL_NOTIFY) {\r
      return EFI_INVALID_PARAMETER;\r
    }\r
  }\r
\r
  return CoreCreateEventInternal (Type, NotifyTpl, NotifyFunction, NotifyContext, EventGroup, Event);\r
}\r
\r
/**\r
  Creates a general-purpose event structure\r
\r
  @param  Type                   The type of event to create and its mode and\r
                                 attributes\r
  @param  NotifyTpl              The task priority level of event notifications\r
  @param  NotifyFunction         Pointer to the events notification function\r
  @param  NotifyContext          Pointer to the notification functions context;\r
                                 corresponds to parameter "Context" in the\r
                                 notification function\r
  @param  EventGroup             GUID for EventGroup if NULL act the same as\r
                                 gBS->CreateEvent().\r
  @param  Event                  Pointer to the newly created event if the call\r
                                 succeeds; undefined otherwise\r
\r
  @retval EFI_SUCCESS            The event structure was created\r
  @retval EFI_INVALID_PARAMETER  One of the parameters has an invalid value\r
  @retval EFI_OUT_OF_RESOURCES   The event could not be allocated\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreCreateEventInternal (\r
  IN UINT32                   Type,\r
  IN EFI_TPL                  NotifyTpl,\r
  IN EFI_EVENT_NOTIFY         NotifyFunction, OPTIONAL\r
  IN CONST VOID               *NotifyContext, OPTIONAL\r
  IN CONST EFI_GUID           *EventGroup,    OPTIONAL\r
  OUT EFI_EVENT               *Event\r
  )\r
{\r
  EFI_STATUS      Status;\r
  IEVENT          *IEvent;\r
  INTN            Index;\r
\r
\r
  if (Event == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Check to make sure no reserved flags are set\r
  //\r
  Status = EFI_INVALID_PARAMETER;\r
  for (Index = 0; Index < (sizeof (mEventTable) / sizeof (UINT32)); Index++) {\r
     if (Type == mEventTable[Index]) {\r
       Status = EFI_SUCCESS;\r
       break;\r
     }\r
  }\r
  if(EFI_ERROR (Status)) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Convert Event type for pre-defined Event groups\r
  //\r
  if (EventGroup != NULL) {\r
    //\r
    // For event group, type EVT_SIGNAL_EXIT_BOOT_SERVICES and EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE\r
    // are not valid\r
    //\r
    if ((Type == EVT_SIGNAL_EXIT_BOOT_SERVICES) || (Type == EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE)) {\r
      return EFI_INVALID_PARAMETER;\r
    }\r
    if (CompareGuid (EventGroup, &gEfiEventExitBootServicesGuid)) {\r
      Type = EVT_SIGNAL_EXIT_BOOT_SERVICES;\r
    } else if (CompareGuid (EventGroup, &gEfiEventVirtualAddressChangeGuid)) {\r
      Type = EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE;\r
    }\r
  } else {\r
    //\r
    // Convert EFI 1.10 Events to their UEFI 2.0 CreateEventEx mapping\r
    //\r
    if (Type == EVT_SIGNAL_EXIT_BOOT_SERVICES) {\r
      EventGroup = &gEfiEventExitBootServicesGuid;\r
    } else if (Type == EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE) {\r
      EventGroup = &gEfiEventVirtualAddressChangeGuid;\r
    }\r
  }\r
\r
  //\r
  // If it's a notify type of event, check its parameters\r
  //\r
  if ((Type & (EVT_NOTIFY_WAIT | EVT_NOTIFY_SIGNAL)) != 0) {\r
    //\r
    // Check for an invalid NotifyFunction or NotifyTpl\r
    //\r
    if ((NotifyFunction == NULL) ||\r
        (NotifyTpl <= TPL_APPLICATION) ||\r
       (NotifyTpl >= TPL_HIGH_LEVEL)) {\r
      return EFI_INVALID_PARAMETER;\r
    }\r
\r
  } else {\r
    //\r
    // No notification needed, zero ignored values\r
    //\r
    NotifyTpl = 0;\r
    NotifyFunction = NULL;\r
    NotifyContext = NULL;\r
  }\r
\r
  //\r
  // Allocate and initialize a new event structure.\r
  //\r
  if ((Type & EVT_RUNTIME) != 0) {\r
    IEvent = AllocateRuntimeZeroPool (sizeof (IEVENT));\r
  } else {\r
    IEvent = AllocateZeroPool (sizeof (IEVENT));\r
  }\r
  if (IEvent == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  IEvent->Signature = EVENT_SIGNATURE;\r
  IEvent->Type = Type;\r
\r
  IEvent->NotifyTpl      = NotifyTpl;\r
  IEvent->NotifyFunction = NotifyFunction;\r
  IEvent->NotifyContext  = (VOID *)NotifyContext;\r
  if (EventGroup != NULL) {\r
    CopyGuid (&IEvent->EventGroup, EventGroup);\r
    IEvent->ExFlag |= EVT_EXFLAG_EVENT_GROUP;\r
  }\r
\r
  *Event = IEvent;\r
\r
  if ((Type & EVT_RUNTIME) != 0) {\r
    //\r
    // Keep a list of all RT events so we can tell the RT AP.\r
    //\r
    IEvent->RuntimeData.Type           = Type;\r
    IEvent->RuntimeData.NotifyTpl      = NotifyTpl;\r
    IEvent->RuntimeData.NotifyFunction = NotifyFunction;\r
    IEvent->RuntimeData.NotifyContext  = (VOID *) NotifyContext;\r
    //\r
    // Work around the bug in the Platform Init specification (v1.7), reported\r
    // as Mantis#2017: "EFI_RUNTIME_EVENT_ENTRY.Event" should have type\r
    // EFI_EVENT, not (EFI_EVENT*). The PI spec documents the field correctly\r
    // as "The EFI_EVENT returned by CreateEvent()", but the type of the field\r
    // doesn't match the natural language description. Therefore we need an\r
    // explicit cast here.\r
    //\r
    IEvent->RuntimeData.Event          = (EFI_EVENT *) IEvent;\r
    InsertTailList (&gRuntime->EventHead, &IEvent->RuntimeData.Link);\r
  }\r
\r
  CoreAcquireEventLock ();\r
\r
  if ((Type & EVT_NOTIFY_SIGNAL) != 0x00000000) {\r
    //\r
    // The Event's NotifyFunction must be queued whenever the event is signaled\r
    //\r
    InsertHeadList (&gEventSignalQueue, &IEvent->SignalLink);\r
  }\r
\r
  CoreReleaseEventLock ();\r
\r
  //\r
  // Done\r
  //\r
  return EFI_SUCCESS;\r
}\r
\r
\r
\r
\r
/**\r
  Signals the event.  Queues the event to be notified if needed.\r
\r
  @param  UserEvent              The event to signal .\r
\r
  @retval EFI_INVALID_PARAMETER  Parameters are not valid.\r
  @retval EFI_SUCCESS            The event was signaled.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreSignalEvent (\r
  IN EFI_EVENT    UserEvent\r
  )\r
{\r
  IEVENT          *Event;\r
\r
  Event = UserEvent;\r
\r
  if (Event == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if (Event->Signature != EVENT_SIGNATURE) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  CoreAcquireEventLock ();\r
\r
  //\r
  // If the event is not already signalled, do so\r
  //\r
\r
  if (Event->SignalCount == 0x00000000) {\r
    Event->SignalCount++;\r
\r
    //\r
    // If signalling type is a notify function, queue it\r
    //\r
    if ((Event->Type & EVT_NOTIFY_SIGNAL) != 0) {\r
      if ((Event->ExFlag & EVT_EXFLAG_EVENT_GROUP) != 0) {\r
        //\r
        // The CreateEventEx() style requires all members of the Event Group\r
        //  to be signaled.\r
        //\r
        CoreReleaseEventLock ();\r
        CoreNotifySignalList (&Event->EventGroup);\r
        CoreAcquireEventLock ();\r
       } else {\r
        CoreNotifyEvent (Event);\r
      }\r
    }\r
  }\r
\r
  CoreReleaseEventLock ();\r
  return EFI_SUCCESS;\r
}\r
\r
\r
\r
/**\r
  Check the status of an event.\r
\r
  @param  UserEvent              The event to check\r
\r
  @retval EFI_SUCCESS            The event is in the signaled state\r
  @retval EFI_NOT_READY          The event is not in the signaled state\r
  @retval EFI_INVALID_PARAMETER  Event is of type EVT_NOTIFY_SIGNAL\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreCheckEvent (\r
  IN EFI_EVENT        UserEvent\r
  )\r
{\r
  IEVENT      *Event;\r
  EFI_STATUS  Status;\r
\r
  Event = UserEvent;\r
\r
  if (Event == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if (Event->Signature != EVENT_SIGNATURE) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if ((Event->Type & EVT_NOTIFY_SIGNAL) != 0) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  Status = EFI_NOT_READY;\r
\r
  if ((Event->SignalCount == 0) && ((Event->Type & EVT_NOTIFY_WAIT) != 0)) {\r
\r
    //\r
    // Queue the wait notify function\r
    //\r
    CoreAcquireEventLock ();\r
    if (Event->SignalCount == 0) {\r
      CoreNotifyEvent (Event);\r
    }\r
    CoreReleaseEventLock ();\r
  }\r
\r
  //\r
  // If the even looks signalled, get the lock and clear it\r
  //\r
\r
  if (Event->SignalCount != 0) {\r
    CoreAcquireEventLock ();\r
\r
    if (Event->SignalCount != 0) {\r
      Event->SignalCount = 0;\r
      Status = EFI_SUCCESS;\r
    }\r
\r
    CoreReleaseEventLock ();\r
  }\r
\r
  return Status;\r
}\r
\r
\r
\r
/**\r
  Stops execution until an event is signaled.\r
\r
  @param  NumberOfEvents         The number of events in the UserEvents array\r
  @param  UserEvents             An array of EFI_EVENT\r
  @param  UserIndex              Pointer to the index of the event which\r
                                 satisfied the wait condition\r
\r
  @retval EFI_SUCCESS            The event indicated by Index was signaled.\r
  @retval EFI_INVALID_PARAMETER  The event indicated by Index has a notification\r
                                 function or Event was not a valid type\r
  @retval EFI_UNSUPPORTED        The current TPL is not TPL_APPLICATION\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreWaitForEvent (\r
  IN UINTN        NumberOfEvents,\r
  IN EFI_EVENT    *UserEvents,\r
  OUT UINTN       *UserIndex\r
  )\r
{\r
  EFI_STATUS      Status;\r
  UINTN           Index;\r
\r
  //\r
  // Can only WaitForEvent at TPL_APPLICATION\r
  //\r
  if (gEfiCurrentTpl != TPL_APPLICATION) {\r
    return EFI_UNSUPPORTED;\r
  }\r
\r
  if (NumberOfEvents == 0) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if (UserEvents == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  for(;;) {\r
\r
    for(Index = 0; Index < NumberOfEvents; Index++) {\r
\r
      Status = CoreCheckEvent (UserEvents[Index]);\r
\r
      //\r
      // provide index of event that caused problem\r
      //\r
      if (Status != EFI_NOT_READY) {\r
        if (UserIndex != NULL) {\r
          *UserIndex = Index;\r
        }\r
        return Status;\r
      }\r
    }\r
\r
    //\r
    // Signal the Idle event\r
    //\r
    CoreSignalEvent (gIdleLoopEvent);\r
  }\r
}\r
\r
\r
/**\r
  Closes an event and frees the event structure.\r
\r
  @param  UserEvent              Event to close\r
\r
  @retval EFI_INVALID_PARAMETER  Parameters are not valid.\r
  @retval EFI_SUCCESS            The event has been closed\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreCloseEvent (\r
  IN EFI_EVENT    UserEvent\r
  )\r
{\r
  EFI_STATUS  Status;\r
  IEVENT      *Event;\r
\r
  Event = UserEvent;\r
\r
  if (Event == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if (Event->Signature != EVENT_SIGNATURE) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // If it's a timer event, make sure it's not pending\r
  //\r
  if ((Event->Type & EVT_TIMER) != 0) {\r
    CoreSetTimer (Event, TimerCancel, 0);\r
  }\r
\r
  CoreAcquireEventLock ();\r
\r
  //\r
  // If the event is queued somewhere, remove it\r
  //\r
\r
  if (Event->RuntimeData.Link.ForwardLink != NULL) {\r
    RemoveEntryList (&Event->RuntimeData.Link);\r
  }\r
\r
  if (Event->NotifyLink.ForwardLink != NULL) {\r
    RemoveEntryList (&Event->NotifyLink);\r
  }\r
\r
  if (Event->SignalLink.ForwardLink != NULL) {\r
    RemoveEntryList (&Event->SignalLink);\r
  }\r
\r
  CoreReleaseEventLock ();\r
\r
  //\r
  // If the event is registered on a protocol notify, then remove it from the protocol database\r
  //\r
  if ((Event->ExFlag & EVT_EXFLAG_EVENT_PROTOCOL_NOTIFICATION) != 0) {\r
    CoreUnregisterProtocolNotify (Event);\r
  }\r
\r
  //\r
  // To avoid the Event to be signalled wrongly after closed,\r
  // clear the Signature of Event before free pool.\r
  //\r
  Event->Signature = 0;\r
  Status = CoreFreePool (Event);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  return Status;\r
}\r
\r