[mirror_edk2.git] / MdeModulePkg / Universal / Network / DpcDxe / Dpc.c

/** @file\r
\r
Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
Module Name:\r
\r
  Dpc.c\r
\r
Abstract:\r
\r
\r
**/\r
\r
#include "Dpc.h"\r
\r
//\r
// Handle for the EFI_DPC_PROTOCOL instance\r
//\r
EFI_HANDLE  mDpcHandle = NULL;\r
\r
//\r
// The EFI_DPC_PROTOCOL instances that is installed onto mDpcHandle\r
//\r
EFI_DPC_PROTOCOL mDpc = {\r
  DpcQueueDpc,\r
  DpcDispatchDpc\r
};\r
\r
//\r
// Global variables used to meaasure the DPC Queue Depths\r
//\r
UINTN  mDpcQueueDepth = 0;\r
UINTN  mMaxDpcQueueDepth = 0;\r
\r
//\r
// Free list of DPC entries.  As DPCs are queued, entries are removed from this\r
// free list.  As DPC entries are dispatched, DPC entries are added to the free list.\r
// If the free list is empty and a DPC is queued, the free list is grown by allocating\r
// an additional set of DPC entries.\r
//\r
LIST_ENTRY      mDpcEntryFreeList = INITIALIZE_LIST_HEAD_VARIABLE(mDpcEntryFreeList);\r
\r
//\r
// An array of DPC queues.  A DPC queue is allocated for every leval EFI_TPL value.\r
// As DPCs are queued, they are added to the end of the linked list.\r
// As DPCs are dispatched, they are removed from the beginning of the linked list.\r
//\r
LIST_ENTRY      mDpcQueue[TPL_HIGH_LEVEL + 1];\r
\r
/**\r
  Add a Deferred Procedure Call to the end of the DPC queue.\r
\r
  @param  This          Protocol instance pointer.\r
  @param  DpcTpl        The EFI_TPL that the DPC should be invoked.\r
  @param  DpcProcedure  Pointer to the DPC's function.\r
  @param  DpcContext    Pointer to the DPC's context.  Passed to DpcProcedure\r
                        when DpcProcedure is invoked.\r
\r
  @retval EFI_SUCCESS            The DPC was queued.\r
  @retval EFI_INVALID_PARAMETER  DpcTpl is not a valid EFI_TPL.\r
  @retval EFI_INVALID_PARAMETER  DpcProcedure is NULL.\r
  @retval EFI_OUT_OF_RESOURCES   There are not enough resources available to\r
                                 add the DPC to the queue.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
DpcQueueDpc (\r
  IN EFI_DPC_PROTOCOL   *This,\r
  IN EFI_TPL            DpcTpl,\r
  IN EFI_DPC_PROCEDURE  DpcProcedure,\r
  IN VOID               *DpcContext    OPTIONAL\r
  )\r
{\r
  EFI_STATUS  ReturnStatus;\r
  EFI_TPL     OriginalTpl;\r
  DPC_ENTRY   *DpcEntry;\r
  UINTN       Index;\r
\r
  //\r
  // Make sure DpcTpl is valid\r
  //\r
  if (DpcTpl < TPL_APPLICATION || DpcTpl > TPL_HIGH_LEVEL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Make sure DpcProcedure is valid\r
  //\r
  if (DpcProcedure == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Assume this function will succeed\r
  //\r
  ReturnStatus = EFI_SUCCESS;\r
\r
  //\r
  // Raise the TPL level to TPL_HIGH_LEVEL for DPC list operation and save the\r
  // current TPL value so it can be restored when this function returns.\r
  //\r
  OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
\r
  //\r
  // Check to see if there are any entries in the DPC free list\r
  //\r
  if (IsListEmpty (&mDpcEntryFreeList)) {\r
    //\r
    // If the current TPL is greater than TPL_NOTIFY, then memory allocations\r
    // can not be performed, so the free list can not be expanded.  In this case\r
    // return EFI_OUT_OF_RESOURCES.\r
    //\r
    if (OriginalTpl > TPL_NOTIFY) {\r
      ReturnStatus = EFI_OUT_OF_RESOURCES;\r
      goto Done;\r
    }\r
\r
    //\r
    // Add 64 DPC entries to the free list\r
    //\r
    for (Index = 0; Index < 64; Index++) {\r
      //\r
      // Lower the TPL level to perform a memory allocation\r
      //\r
      gBS->RestoreTPL (OriginalTpl);\r
\r
      //\r
      // Allocate a new DPC entry\r
      //\r
      DpcEntry = AllocatePool (sizeof (DPC_ENTRY));\r
\r
      //\r
      // Raise the TPL level back to TPL_HIGH_LEVEL for DPC list operations\r
      //\r
      gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
\r
      //\r
      // If the allocation of a DPC entry fails, and the free list is empty,\r
      // then return EFI_OUT_OF_RESOURCES.\r
      //\r
      if (DpcEntry == NULL) {\r
        if (IsListEmpty (&mDpcEntryFreeList)) {\r
          ReturnStatus = EFI_OUT_OF_RESOURCES;\r
          goto Done;\r
        }\r
      }\r
\r
      //\r
      // Add the newly allocated DPC entry to the DPC free list\r
      //\r
      InsertTailList (&mDpcEntryFreeList, &DpcEntry->ListEntry);\r
    }\r
  }\r
\r
  //\r
  // Retrieve the first node from the free list of DPCs\r
  //\r
  DpcEntry = (DPC_ENTRY *)(GetFirstNode (&mDpcEntryFreeList));\r
\r
  //\r
  // Remove the first node from the free list of DPCs\r
  //\r
  RemoveEntryList (&DpcEntry->ListEntry);\r
\r
  //\r
  // Fill in the DPC entry with the DpcProcedure and DpcContext\r
  //\r
  DpcEntry->DpcProcedure = DpcProcedure;\r
  DpcEntry->DpcContext   = DpcContext;\r
\r
  //\r
  // Add the DPC entry to the end of the list for the specified DplTpl.\r
  //\r
  InsertTailList (&mDpcQueue[DpcTpl], &DpcEntry->ListEntry);\r
\r
  //\r
  // Increment the measured DPC queue depth across all TPLs\r
  //\r
  mDpcQueueDepth++;\r
\r
  //\r
  // Measure the maximum DPC queue depth across all TPLs\r
  //\r
  if (mDpcQueueDepth > mMaxDpcQueueDepth) {\r
    mMaxDpcQueueDepth = mDpcQueueDepth;\r
  }\r
\r
Done:\r
  //\r
  // Restore the original TPL level when this function was called\r
  //\r
  gBS->RestoreTPL (OriginalTpl);\r
\r
  return ReturnStatus;\r
}\r
\r
/**\r
  Dispatch the queue of DPCs.  ALL DPCs that have been queued with a DpcTpl\r
  value greater than or equal to the current TPL are invoked in the order that\r
  they were queued.  DPCs with higher DpcTpl values are invoked before DPCs with\r
  lower DpcTpl values.\r
\r
  @param  This  Protocol instance pointer.\r
\r
  @retval EFI_SUCCESS    One or more DPCs were invoked.\r
  @retval EFI_NOT_FOUND  No DPCs were invoked.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
DpcDispatchDpc (\r
  IN EFI_DPC_PROTOCOL  *This\r
  )\r
{\r
  EFI_STATUS  ReturnStatus;\r
  EFI_TPL     OriginalTpl;\r
  EFI_TPL     Tpl;\r
  DPC_ENTRY   *DpcEntry;\r
\r
  //\r
  // Assume that no DPCs will be invoked\r
  //\r
  ReturnStatus = EFI_NOT_FOUND;\r
\r
  //\r
  // Raise the TPL level to TPL_HIGH_LEVEL for DPC list operation and save the\r
  // current TPL value so it can be restored when this function returns.\r
  //\r
  OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
\r
  //\r
  // Check to see if there are 1 or more DPCs currently queued\r
  //\r
  if (mDpcQueueDepth > 0) {\r
    //\r
    // Loop from TPL_HIGH_LEVEL down to the current TPL value\r
    //\r
    for (Tpl = TPL_HIGH_LEVEL; Tpl >= OriginalTpl; Tpl--) {\r
      //\r
      // Check to see if the DPC queue is empty\r
      //\r
      while (!IsListEmpty (&mDpcQueue[Tpl])) {\r
        //\r
        // Retrieve the first DPC entry from the DPC queue specified by Tpl\r
        //\r
        DpcEntry = (DPC_ENTRY *)(GetFirstNode (&mDpcQueue[Tpl]));\r
\r
        //\r
        // Remove the first DPC entry from the DPC queue specified by Tpl\r
        //\r
        RemoveEntryList (&DpcEntry->ListEntry);\r
\r
        //\r
        // Decrement the measured DPC Queue Depth across all TPLs\r
        //\r
        mDpcQueueDepth--;\r
\r
        //\r
        // Lower the TPL to TPL value of the current DPC queue\r
        //\r
        gBS->RestoreTPL (Tpl);\r
\r
        //\r
        // Invoke the DPC passing in its context\r
        //\r
        (DpcEntry->DpcProcedure) (DpcEntry->DpcContext);\r
\r
        //\r
        // At least one DPC has been invoked, so set the return status to EFI_SUCCESS\r
        //\r
        ReturnStatus = EFI_SUCCESS;\r
\r
        //\r
        // Raise the TPL level back to TPL_HIGH_LEVEL for DPC list operations\r
        //\r
        gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
\r
        //\r
        // Add the invoked DPC entry to the DPC free list\r
        //\r
        InsertTailList (&mDpcEntryFreeList, &DpcEntry->ListEntry);\r
      }\r
    }\r
  }\r
\r
  //\r
  // Restore the original TPL level when this function was called\r
  //\r
  gBS->RestoreTPL (OriginalTpl);\r
\r
  return ReturnStatus;\r
}\r
\r
/**\r
  The entry point for DPC driver which installs the EFI_DPC_PROTOCOL onto a new handle.\r
\r
  @param  ImageHandle            The image handle of the driver.\r
  @param  SystemTable            The system table.\r
\r
  @retval EFI_SUCCES             The DPC queues were initialized and the EFI_DPC_PROTOCOL was\r
                                 installed onto a new handle.\r
  @retval Others                 Failed to install EFI_DPC_PROTOCOL.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
DpcDriverEntryPoint (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
{\r
  EFI_STATUS  Status;\r
  UINTN       Index;\r
\r
  //\r
  // ASSERT() if the EFI_DPC_PROTOCOL is already present in the handle database\r
  //\r
  ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiDpcProtocolGuid);\r
\r
  //\r
  // Initialize the DPC queue for all possible TPL values\r
  //\r
  for (Index = 0; Index <= TPL_HIGH_LEVEL; Index++) {\r
    InitializeListHead (&mDpcQueue[Index]);\r
  }\r
\r
  //\r
  // Install the EFI_DPC_PROTOCOL instance onto a new handle\r
  //\r
  Status = gBS->InstallMultipleProtocolInterfaces (\r
                  &mDpcHandle,\r
                  &gEfiDpcProtocolGuid,\r
                  &mDpc,\r
                  NULL\r
                  );\r
  ASSERT_EFI_ERROR (Status);\r
\r
  return Status;\r
}\r
Commit	Line	Data
36ee91ca	1	/** @file\r
36ee91ca	2	\r
d1102dba	3	Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>\r
9d510e61	4	SPDX-License-Identifier: BSD-2-Clause-Patent\r
36ee91ca	5	\r
	6	Module Name:\r
	7	\r
	8	Dpc.c\r
	9	\r
	10	Abstract:\r
	11	\r
	12	\r
	13	**/\r
	14	\r
	15	#include "Dpc.h"\r
	16	\r
	17	//\r
	18	// Handle for the EFI_DPC_PROTOCOL instance\r
	19	//\r
	20	EFI_HANDLE mDpcHandle = NULL;\r
	21	\r
	22	//\r
	23	// The EFI_DPC_PROTOCOL instances that is installed onto mDpcHandle\r
	24	//\r
	25	EFI_DPC_PROTOCOL mDpc = {\r
	26	DpcQueueDpc,\r
	27	DpcDispatchDpc\r
	28	};\r
	29	\r
	30	//\r
	31	// Global variables used to meaasure the DPC Queue Depths\r
	32	//\r
	33	UINTN mDpcQueueDepth = 0;\r
	34	UINTN mMaxDpcQueueDepth = 0;\r
	35	\r
	36	//\r
	37	// Free list of DPC entries. As DPCs are queued, entries are removed from this\r
	38	// free list. As DPC entries are dispatched, DPC entries are added to the free list.\r
	39	// If the free list is empty and a DPC is queued, the free list is grown by allocating\r
	40	// an additional set of DPC entries.\r
	41	//\r
e48e37fc	42	LIST_ENTRY mDpcEntryFreeList = INITIALIZE_LIST_HEAD_VARIABLE(mDpcEntryFreeList);\r
36ee91ca	43	\r
	44	//\r
	45	// An array of DPC queues. A DPC queue is allocated for every leval EFI_TPL value.\r
	46	// As DPCs are queued, they are added to the end of the linked list.\r
	47	// As DPCs are dispatched, they are removed from the beginning of the linked list.\r
	48	//\r
e48e37fc	49	LIST_ENTRY mDpcQueue[TPL_HIGH_LEVEL + 1];\r
36ee91ca	50	\r
	51	/**\r
	52	Add a Deferred Procedure Call to the end of the DPC queue.\r
	53	\r
	54	@param This Protocol instance pointer.\r
	55	@param DpcTpl The EFI_TPL that the DPC should be invoked.\r
	56	@param DpcProcedure Pointer to the DPC's function.\r
	57	@param DpcContext Pointer to the DPC's context. Passed to DpcProcedure\r
	58	when DpcProcedure is invoked.\r
	59	\r
	60	@retval EFI_SUCCESS The DPC was queued.\r
	61	@retval EFI_INVALID_PARAMETER DpcTpl is not a valid EFI_TPL.\r
	62	@retval EFI_INVALID_PARAMETER DpcProcedure is NULL.\r
	63	@retval EFI_OUT_OF_RESOURCES There are not enough resources available to\r
	64	add the DPC to the queue.\r
	65	\r
	66	**/\r
	67	EFI_STATUS\r
	68	EFIAPI\r
	69	DpcQueueDpc (\r
	70	IN EFI_DPC_PROTOCOL *This,\r
	71	IN EFI_TPL DpcTpl,\r
	72	IN EFI_DPC_PROCEDURE DpcProcedure,\r
	73	IN VOID *DpcContext OPTIONAL\r
	74	)\r
	75	{\r
	76	EFI_STATUS ReturnStatus;\r
	77	EFI_TPL OriginalTpl;\r
	78	DPC_ENTRY *DpcEntry;\r
	79	UINTN Index;\r
	80	\r
	81	//\r
	82	// Make sure DpcTpl is valid\r
	83	//\r
	84	if (DpcTpl < TPL_APPLICATION \|\| DpcTpl > TPL_HIGH_LEVEL) {\r
	85	return EFI_INVALID_PARAMETER;\r
	86	}\r
	87	\r
	88	//\r
	89	// Make sure DpcProcedure is valid\r
	90	//\r
	91	if (DpcProcedure == NULL) {\r
	92	return EFI_INVALID_PARAMETER;\r
	93	}\r
	94	\r
	95	//\r
	96	// Assume this function will succeed\r
	97	//\r
	98	ReturnStatus = EFI_SUCCESS;\r
	99	\r
	100	//\r
	101	// Raise the TPL level to TPL_HIGH_LEVEL for DPC list operation and save the\r
	102	// current TPL value so it can be restored when this function returns.\r
	103	//\r
	104	OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
	105	\r
	106	//\r
	107	// Check to see if there are any entries in the DPC free list\r
	108	//\r
	109	if (IsListEmpty (&mDpcEntryFreeList)) {\r
	110	//\r
	111	// If the current TPL is greater than TPL_NOTIFY, then memory allocations\r
	112	// can not be performed, so the free list can not be expanded. In this case\r
	113	// return EFI_OUT_OF_RESOURCES.\r
114	//\r
115	if (OriginalTpl > TPL_NOTIFY) {\r
116	ReturnStatus = EFI_OUT_OF_RESOURCES;\r
117	goto Done;\r
118	}\r
119	\r
120	//\r
121	// Add 64 DPC entries to the free list\r
122	//\r
123	for (Index = 0; Index < 64; Index++) {\r
124	//\r
125	// Lower the TPL level to perform a memory allocation\r
126	//\r
127	gBS->RestoreTPL (OriginalTpl);\r
128	\r
129	//\r
130	// Allocate a new DPC entry\r
131	//\r
132	DpcEntry = AllocatePool (sizeof (DPC_ENTRY));\r
133	\r
134	//\r
135	// Raise the TPL level back to TPL_HIGH_LEVEL for DPC list operations\r
136	//\r
137	gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
138	\r
139	//\r
140	// If the allocation of a DPC entry fails, and the free list is empty,\r
141	// then return EFI_OUT_OF_RESOURCES.\r
142	//\r
143	if (DpcEntry == NULL) {\r
144	if (IsListEmpty (&mDpcEntryFreeList)) {\r
145	ReturnStatus = EFI_OUT_OF_RESOURCES;\r
146	goto Done;\r
147	}\r
148	}\r
149	\r
150	//\r
151	// Add the newly allocated DPC entry to the DPC free list\r
152	//\r
153	InsertTailList (&mDpcEntryFreeList, &DpcEntry->ListEntry);\r
154	}\r
155	}\r
156	\r
157	//\r
158	// Retrieve the first node from the free list of DPCs\r
159	//\r
160	DpcEntry = (DPC_ENTRY *)(GetFirstNode (&mDpcEntryFreeList));\r
161	\r
162	//\r
163	// Remove the first node from the free list of DPCs\r
164	//\r
165	RemoveEntryList (&DpcEntry->ListEntry);\r
166	\r
167	//\r
168	// Fill in the DPC entry with the DpcProcedure and DpcContext\r
169	//\r
170	DpcEntry->DpcProcedure = DpcProcedure;\r
171	DpcEntry->DpcContext = DpcContext;\r
172	\r
173	//\r
174	// Add the DPC entry to the end of the list for the specified DplTpl.\r
175	//\r
176	InsertTailList (&mDpcQueue[DpcTpl], &DpcEntry->ListEntry);\r
177	\r
178	//\r
179	// Increment the measured DPC queue depth across all TPLs\r
180	//\r
181	mDpcQueueDepth++;\r
182	\r
183	//\r
184	// Measure the maximum DPC queue depth across all TPLs\r
185	//\r
186	if (mDpcQueueDepth > mMaxDpcQueueDepth) {\r
187	mMaxDpcQueueDepth = mDpcQueueDepth;\r
188	}\r
189	\r
190	Done:\r
191	//\r
192	// Restore the original TPL level when this function was called\r
193	//\r
194	gBS->RestoreTPL (OriginalTpl);\r
195	\r
196	return ReturnStatus;\r
197	}\r
198	\r
199	/**\r
200	Dispatch the queue of DPCs. ALL DPCs that have been queued with a DpcTpl\r
201	value greater than or equal to the current TPL are invoked in the order that\r
202	they were queued. DPCs with higher DpcTpl values are invoked before DPCs with\r
203	lower DpcTpl values.\r
204	\r
205	@param This Protocol instance pointer.\r
206	\r
207	@retval EFI_SUCCESS One or more DPCs were invoked.\r
208	@retval EFI_NOT_FOUND No DPCs were invoked.\r
209	\r
210	**/\r
211	EFI_STATUS\r
212	EFIAPI\r
213	DpcDispatchDpc (\r
214	IN EFI_DPC_PROTOCOL *This\r
215	)\r
216	{\r
217	EFI_STATUS ReturnStatus;\r
218	EFI_TPL OriginalTpl;\r
219	EFI_TPL Tpl;\r
220	DPC_ENTRY *DpcEntry;\r
221	\r
222	//\r
223	// Assume that no DPCs will be invoked\r
224	//\r
225	ReturnStatus = EFI_NOT_FOUND;\r
226	\r
227	//\r
228	// Raise the TPL level to TPL_HIGH_LEVEL for DPC list operation and save the\r
229	// current TPL value so it can be restored when this function returns.\r
230	//\r
231	OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
232	\r
233	//\r
234	// Check to see if there are 1 or more DPCs currently queued\r
235	//\r
236	if (mDpcQueueDepth > 0) {\r
237	//\r
238	// Loop from TPL_HIGH_LEVEL down to the current TPL value\r
239	//\r
240	for (Tpl = TPL_HIGH_LEVEL; Tpl >= OriginalTpl; Tpl--) {\r
241	//\r
242	// Check to see if the DPC queue is empty\r
243	//\r
244	while (!IsListEmpty (&mDpcQueue[Tpl])) {\r
245	//\r
246	// Retrieve the first DPC entry from the DPC queue specified by Tpl\r
247	//\r
248	DpcEntry = (DPC_ENTRY *)(GetFirstNode (&mDpcQueue[Tpl]));\r
249	\r
250	//\r
251	// Remove the first DPC entry from the DPC queue specified by Tpl\r
252	//\r
253	RemoveEntryList (&DpcEntry->ListEntry);\r
254	\r
255	//\r
256	// Decrement the measured DPC Queue Depth across all TPLs\r
257	//\r
258	mDpcQueueDepth--;\r
259	\r
260	//\r
261	// Lower the TPL to TPL value of the current DPC queue\r
262	//\r
263	gBS->RestoreTPL (Tpl);\r
264	\r
265	//\r
266	// Invoke the DPC passing in its context\r
267	//\r
268	(DpcEntry->DpcProcedure) (DpcEntry->DpcContext);\r
269	\r
270	//\r
271	// At least one DPC has been invoked, so set the return status to EFI_SUCCESS\r
272	//\r
273	ReturnStatus = EFI_SUCCESS;\r
274	\r
275	//\r
276	// Raise the TPL level back to TPL_HIGH_LEVEL for DPC list operations\r
277	//\r
278	gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
279	\r
280	//\r
281	// Add the invoked DPC entry to the DPC free list\r
282	//\r
283	InsertTailList (&mDpcEntryFreeList, &DpcEntry->ListEntry);\r
284	}\r
285	}\r
286	}\r
287	\r
288	//\r
289	// Restore the original TPL level when this function was called\r
290	//\r
291	gBS->RestoreTPL (OriginalTpl);\r
292	\r
293	return ReturnStatus;\r
294	}\r
295	\r
7bce0c5a	296	/**\r
	297	The entry point for DPC driver which installs the EFI_DPC_PROTOCOL onto a new handle.\r
	298	\r
	299	@param ImageHandle The image handle of the driver.\r
	300	@param SystemTable The system table.\r
	301	\r
	302	@retval EFI_SUCCES The DPC queues were initialized and the EFI_DPC_PROTOCOL was\r
	303	installed onto a new handle.\r
	304	@retval Others Failed to install EFI_DPC_PROTOCOL.\r
	305	\r
	306	**/\r
36ee91ca	307	EFI_STATUS\r
	308	EFIAPI\r
	309	DpcDriverEntryPoint (\r
	310	IN EFI_HANDLE ImageHandle,\r
	311	IN EFI_SYSTEM_TABLE *SystemTable\r
	312	)\r
36ee91ca	313	{\r
	314	EFI_STATUS Status;\r
	315	UINTN Index;\r
	316	\r
	317	//\r
	318	// ASSERT() if the EFI_DPC_PROTOCOL is already present in the handle database\r
	319	//\r
	320	ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiDpcProtocolGuid);\r
	321	\r
	322	//\r
	323	// Initialize the DPC queue for all possible TPL values\r
	324	//\r
	325	for (Index = 0; Index <= TPL_HIGH_LEVEL; Index++) {\r
	326	InitializeListHead (&mDpcQueue[Index]);\r
	327	}\r
	328	\r
	329	//\r
	330	// Install the EFI_DPC_PROTOCOL instance onto a new handle\r
	331	//\r
	332	Status = gBS->InstallMultipleProtocolInterfaces (\r
	333	&mDpcHandle,\r
d1102dba	334	&gEfiDpcProtocolGuid,\r
c4a62a12	335	&mDpc,\r
36ee91ca	336	NULL\r
	337	);\r
	338	ASSERT_EFI_ERROR (Status);\r
	339	\r
	340	return Status;\r
	341	}\r