Пример #1
0
static void prvUnlockQueue( xQueueHandle pxQueue )
{
	/* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */

	/* The lock counts contains the number of extra data items placed or
	removed from the queue while the queue was locked.  When a queue is
	locked items can be added or removed, but the event lists cannot be
	updated. */
	taskENTER_CRITICAL();
	{
		--( pxQueue->xTxLock );

		/* See if data was added to the queue while it was locked. */
		if( pxQueue->xTxLock > queueUNLOCKED )
		{
			pxQueue->xTxLock = queueUNLOCKED;

			/* Data was posted while the queue was locked.  Are any tasks
			blocked waiting for data to become available? */
			if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
			{
				/* Tasks that are removed from the event list will get added to
				the pending ready list as the scheduler is still suspended. */
				if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
				{
					/* The task waiting has a higher priority so record that a
					context	switch is required. */
					vTaskMissedYield();
				}
			}			
		}
	}
	taskEXIT_CRITICAL();

	/* Do the same for the Rx lock. */
	taskENTER_CRITICAL();
	{
		--( pxQueue->xRxLock );

		if( pxQueue->xRxLock > queueUNLOCKED )
		{
			pxQueue->xRxLock = queueUNLOCKED;

			if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
			{
				if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
				{
					vTaskMissedYield();
				}
			}			
		}
	}
	taskEXIT_CRITICAL();
}
Пример #2
0
	static void vDNSDoCallback( TickType_t xIdentifier, const char *pcName, uint32_t ulIPAddress )
	{
		const ListItem_t *pxIterator;
		const MiniListItem_t* xEnd = ( const MiniListItem_t* )listGET_END_MARKER( &xCallbackList );

		vTaskSuspendAll();
		{
			for( pxIterator  = ( const ListItem_t * ) listGET_NEXT( xEnd );
				 pxIterator != ( const ListItem_t * ) xEnd;
				 pxIterator  = ( const ListItem_t * ) listGET_NEXT( pxIterator ) )
			{
				if( listGET_LIST_ITEM_VALUE( pxIterator ) == xIdentifier )
				{
					DNSCallback_t *pxCallback = ( DNSCallback_t * ) listGET_LIST_ITEM_OWNER( pxIterator );
					pxCallback->pCallbackFunction( pcName, pxCallback->pvSearchID, ulIPAddress );
					uxListRemove( &pxCallback->xListItem );
					vPortFree( pxCallback );
					if( listLIST_IS_EMPTY( &xCallbackList ) )
					{
						vIPSetDnsTimerEnableState( pdFALSE );
					}
					break;
				}
			}
		}
		xTaskResumeAll();
	}
void vCoRoutineSchedule( void )
{
	/* See if any co-routines readied by events need moving to the ready lists. */
	prvCheckPendingReadyList();

	/* See if any delayed co-routines have timed out. */
	prvCheckDelayedList();

	/* Find the highest priority queue that contains ready co-routines. */
	while( listLIST_IS_EMPTY( &( pxReadyCoRoutineLists[ uxTopCoRoutineReadyPriority ] ) ) )
	{
		if( uxTopCoRoutineReadyPriority == 0 )
		{
			/* No more co-routines to check. */
			return;
		}
		--uxTopCoRoutineReadyPriority;
	}

	/* listGET_OWNER_OF_NEXT_ENTRY walks through the list, so the co-routines
	 of the	same priority get an equal share of the processor time. */
	listGET_OWNER_OF_NEXT_ENTRY( pxCurrentCoRoutine, &( pxReadyCoRoutineLists[ uxTopCoRoutineReadyPriority ] ) );

	/* Call the co-routine. */
	( pxCurrentCoRoutine->pxCoRoutineFunction )( pxCurrentCoRoutine, pxCurrentCoRoutine->uxIndex );

	return;
}
Пример #4
0
	void vDNSCheckCallBack( void *pvSearchID )
	{
	const ListItem_t *pxIterator;
	const MiniListItem_t* xEnd = ( const MiniListItem_t* )listGET_END_MARKER( &xCallbackList );

		vTaskSuspendAll();
		{
			for( pxIterator  = ( const ListItem_t * ) listGET_NEXT( xEnd );
				 pxIterator != ( const ListItem_t * ) xEnd;
				  )
			{
				DNSCallback_t *pxCallback = ( DNSCallback_t * ) listGET_LIST_ITEM_OWNER( pxIterator );
				/* Move to the next item because we might remove this item */
				pxIterator  = ( const ListItem_t * ) listGET_NEXT( pxIterator );
				if( ( pvSearchID != NULL ) && ( pvSearchID == pxCallback->pvSearchID ) )
				{
					uxListRemove( &pxCallback->xListItem );
					vPortFree( pxCallback );
				}
				else if( xTaskCheckForTimeOut( &pxCallback->xTimeoutState, &pxCallback->xRemaningTime ) != pdFALSE )
				{
					pxCallback->pCallbackFunction( pxCallback->pcName, pxCallback->pvSearchID, 0 );
					uxListRemove( &pxCallback->xListItem );
					vPortFree( ( void * ) pxCallback );
				}
			}
		}
		xTaskResumeAll();

		if( listLIST_IS_EMPTY( &xCallbackList ) )
		{
			vIPSetDnsTimerEnableState( pdFALSE );
		}
	}
Пример #5
0
	static void vDNSSetCallBack( const char *pcHostName, void *pvSearchID, FOnDNSEvent pCallbackFunction, TickType_t xTimeout, TickType_t xIdentifier )
	{
		size_t lLength = strlen( pcHostName );
		DNSCallback_t *pxCallback = ( DNSCallback_t * )pvPortMalloc( sizeof( *pxCallback ) + lLength );

		/* Translate from ms to number of clock ticks. */
		xTimeout /= portTICK_PERIOD_MS;
		if( pxCallback != NULL )
		{
			if( listLIST_IS_EMPTY( &xCallbackList ) )
			{
				/* This is the first one, start the DNS timer to check for timeouts */
				vIPReloadDNSTimer( FreeRTOS_min_uint32( 1000U, xTimeout ) );
			}
			strcpy( pxCallback->pcName, pcHostName );
			pxCallback->pCallbackFunction = pCallbackFunction;
			pxCallback->pvSearchID = pvSearchID;
			pxCallback->xRemaningTime = xTimeout;
			vTaskSetTimeOutState( &pxCallback->xTimeoutState );
			listSET_LIST_ITEM_OWNER( &( pxCallback->xListItem ), ( void* ) pxCallback );
			listSET_LIST_ITEM_VALUE( &( pxCallback->xListItem ), xIdentifier );
			vTaskSuspendAll();
			{
				vListInsertEnd( &xCallbackList, &pxCallback->xListItem );
			}
			xTaskResumeAll();
		}
	}
Пример #6
0
static void prvProcessTimerOrBlockTask( const TickType_t xNextExpireTime, BaseType_t xListWasEmpty )
{
TickType_t xTimeNow;
BaseType_t xTimerListsWereSwitched;

	vTaskSuspendAll();
	{
		/* Obtain the time now to make an assessment as to whether the timer
		has expired or not.  If obtaining the time causes the lists to switch
		then don't process this timer as any timers that remained in the list
		when the lists were switched will have been processed within the
		prvSampleTimeNow() function. */
		xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
		if( xTimerListsWereSwitched == pdFALSE )
		{
			/* The tick count has not overflowed, has the timer expired? */
			if( ( xListWasEmpty == pdFALSE ) && ( xNextExpireTime <= xTimeNow ) )
			{
				( void ) xTaskResumeAll();
				prvProcessExpiredTimer( xNextExpireTime, xTimeNow );
			}
			else
			{
				/* The tick count has not overflowed, and the next expire
				time has not been reached yet.  This task should therefore
				block to wait for the next expire time or a command to be
				received - whichever comes first.  The following line cannot
				be reached unless xNextExpireTime > xTimeNow, except in the
				case when the current timer list is empty. */
				if( xListWasEmpty != pdFALSE )
				{
					/* The current timer list is empty - is the overflow list
					also empty? */
					xListWasEmpty = listLIST_IS_EMPTY( pxOverflowTimerList );
				}

				vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ), xListWasEmpty );

				if( xTaskResumeAll() == pdFALSE )
				{
					/* Yield to wait for either a command to arrive, or the
					block time to expire.  If a command arrived between the
					critical section being exited and this yield then the yield
					will not cause the task to block. */
					portYIELD_WITHIN_API();
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
		}
		else
		{
			( void ) xTaskResumeAll();
		}
	}
}
Пример #7
0
static void prvCheckDelayedList( void )
{
corCRCB *pxCRCB;

	xPassedTicks = xTaskGetTickCount() - xLastTickCount;
	while( xPassedTicks )
	{
		xCoRoutineTickCount++;
		xPassedTicks--;

		/* If the tick count has overflowed we need to swap the ready lists. */
		if( xCoRoutineTickCount == 0 )
		{
			xList * pxTemp;

			/* Tick count has overflowed so we need to swap the delay lists.  If there are
			any items in pxDelayedCoRoutineList here then there is an error! */
			pxTemp = pxDelayedCoRoutineList;
			pxDelayedCoRoutineList = pxOverflowDelayedCoRoutineList;
			pxOverflowDelayedCoRoutineList = pxTemp;
		}

		/* See if this tick has made a timeout expire. */
		while( listLIST_IS_EMPTY( pxDelayedCoRoutineList ) == pdFALSE )
		{
			pxCRCB = ( corCRCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxDelayedCoRoutineList );

			if( xCoRoutineTickCount < listGET_LIST_ITEM_VALUE( &( pxCRCB->xGenericListItem ) ) )
			{
				/* Timeout not yet expired. */
				break;
			}

			//portDISABLE_INTERRUPTS();
PortDisableInt_NoNest();
			{
				/* The event could have occurred just before this critical
				section.  If this is the case then the generic list item will
				have been moved to the pending ready list and the following
				line is still valid.  Also the pvContainer parameter will have
				been set to NULL so the following lines are also valid. */
				uxListRemove( &( pxCRCB->xGenericListItem ) );

				/* Is the co-routine waiting on an event also? */
				if( pxCRCB->xEventListItem.pvContainer )
				{
					( void ) uxListRemove( &( pxCRCB->xEventListItem ) );
				}
			}
//			portENABLE_INTERRUPTS();
PortEnableInt_NoNest();

			prvAddCoRoutineToReadyQueue( pxCRCB );
		}
	}

	xLastTickCount = xCoRoutineTickCount;
}
Пример #8
0
static void prvSwitchTimerLists( void )
{
TickType_t xNextExpireTime, xReloadTime;
List_t *pxTemp;
Timer_t *pxTimer;
BaseType_t xResult;

	/* The tick count has overflowed.  The timer lists must be switched.
	If there are any timers still referenced from the current timer list
	then they must have expired and should be processed before the lists
	are switched. */
	while( listLIST_IS_EMPTY( pxCurrentTimerList ) == pdFALSE )
	{
		xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );

		/* Remove the timer from the list. */
		pxTimer = ( Timer_t * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );
		( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
		traceTIMER_EXPIRED( pxTimer );

		/* Execute its callback, then send a command to restart the timer if
		it is an auto-reload timer.  It cannot be restarted here as the lists
		have not yet been switched. */
		pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );

		if( pxTimer->uxAutoReload == ( UBaseType_t ) pdTRUE )
		{
			/* Calculate the reload value, and if the reload value results in
			the timer going into the same timer list then it has already expired
			and the timer should be re-inserted into the current list so it is
			processed again within this loop.  Otherwise a command should be sent
			to restart the timer to ensure it is only inserted into a list after
			the lists have been swapped. */
			xReloadTime = ( xNextExpireTime + pxTimer->xTimerPeriodInTicks );
			if( xReloadTime > xNextExpireTime )
			{
				listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xReloadTime );
				listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
				vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
			}
			else
			{
				xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START_DONT_TRACE, xNextExpireTime, NULL, tmrNO_DELAY );
				configASSERT( xResult );
				( void ) xResult;
			}
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}
	}

	pxTemp = pxCurrentTimerList;
	pxCurrentTimerList = pxOverflowTimerList;
	pxOverflowTimerList = pxTemp;
}
Пример #9
0
signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxTaskWoken )
{
signed portBASE_TYPE xReturn;

	/* We cannot block from an ISR, so check there is data available. */
	if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
	{
		/* Copy the data from the queue. */
		pxQueue->pcReadFrom += pxQueue->uxItemSize;
		if( pxQueue->pcReadFrom >= pxQueue->pcTail )
		{
			pxQueue->pcReadFrom = pxQueue->pcHead;
		}
		--( pxQueue->uxMessagesWaiting );
		
		if(pvBuffer != (void*)0UL)
		{
			memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
		}

		/* If the queue is locked we will not modify the event list.  Instead
		we update the lock count so the task that unlocks the queue will know
		that an ISR has removed data while the queue was locked. */
		if( pxQueue->xRxLock == queueUNLOCKED )
		{
			/* We only want to wake one task per ISR, so check that a task has
			not already been woken. */
			if( !( *pxTaskWoken ) )
			{
				if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
					{
						/* The task waiting has a higher priority than us so
						force a context switch. */
						*pxTaskWoken = pdTRUE;
					}
				}
			}
		}
		else
		{
			/* Increment the lock count so the task that unlocks the queue
			knows that data was removed while it was locked. */
			++( pxQueue->xRxLock );
		}

		xReturn = pdPASS;
	}
	else
	{
		xReturn = pdFAIL;
	}

	return xReturn;
}
void IBN_GetTaskList (void)
{
	u32 Queue_u32;

	IBN_TasklistCounter_u8 = 0;

// Scan all running queues
	portENTER_CRITICAL();

// Scan ready lists
	Queue_u32 = uxTopUsedPriority + 1;
	do
	{
		Queue_u32--;
		if( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ Queue_u32 ] ) ) )
		{
			IBN_GetTaskListEntrys ( &(pxReadyTasksLists[ Queue_u32 ]),IBN_TASK_STATE_RUNNING);
		}
	} while( Queue_u32 > ( unsigned short ) tskIDLE_PRIORITY );


	if( !listLIST_IS_EMPTY( pxDelayedTaskList ) )
	{
		IBN_GetTaskListEntrys (pxDelayedTaskList,IBN_TASK_STATE_DELAYED);
	}

	if( !listLIST_IS_EMPTY( pxOverflowDelayedTaskList ) )
	{
		IBN_GetTaskListEntrys (pxOverflowDelayedTaskList,IBN_TASK_STATE_DELAYED_OVER);
	}

	if( !listLIST_IS_EMPTY( &xSuspendedTaskList ) )
	{
		IBN_GetTaskListEntrys (&xSuspendedTaskList,IBN_TASK_STATE_SUSPEND);
	}

	portEXIT_CRITICAL();

}
Пример #11
0
signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition )
{
signed portBASE_TYPE xReturn;
unsigned portBASE_TYPE uxSavedInterruptStatus;

	/* Similar to xQueueGenericSend, except we don't block if there is no room
	in the queue.  Also we don't directly wake a task that was blocked on a
	queue read, instead we return a flag to say whether a context switch is
	required or not (i.e. has a task with a higher priority than us been woken
	by this	post). */
	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
	{
		if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
		{
			traceQUEUE_SEND_FROM_ISR( pxQueue );

			prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );

			/* If the queue is locked we do not alter the event list.  This will
			be done when the queue is unlocked later. */
			if( pxQueue->xTxLock == queueUNLOCKED )
			{
				if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
					{
						/* The task waiting has a higher priority so record that a
						context	switch is required. */
						*pxHigherPriorityTaskWoken = pdTRUE;
					}
				}
			}
			else
			{
				/* Increment the lock count so the task that unlocks the queue
				knows that data was posted while it was locked. */
				++( pxQueue->xTxLock );
			}

			xReturn = pdPASS;
		}
		else
		{
			traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
			xReturn = errQUEUE_FULL;
		}
	}
	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

	return xReturn;
}
Пример #12
0
signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxTaskWoken )
{
signed portBASE_TYPE xReturn;
unsigned portBASE_TYPE uxSavedInterruptStatus;

	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
	{
		/* We cannot block from an ISR, so check there is data available. */
		if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
		{
			traceQUEUE_RECEIVE_FROM_ISR( pxQueue );

			prvCopyDataFromQueue( pxQueue, pvBuffer );
			--( pxQueue->uxMessagesWaiting );

			/* If the queue is locked we will not modify the event list.  Instead
			we update the lock count so the task that unlocks the queue will know
			that an ISR has removed data while the queue was locked. */
			if( pxQueue->xRxLock == queueUNLOCKED )
			{
				if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
					{
						/* The task waiting has a higher priority than us so
						force a context switch. */
						*pxTaskWoken = pdTRUE;
					}
				}
			}
			else
			{
				/* Increment the lock count so the task that unlocks the queue
				knows that data was removed while it was locked. */
				++( pxQueue->xRxLock );
			}

			xReturn = pdPASS;
		}
		else
		{
			xReturn = pdFAIL;
			traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue );
		}
	}
	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

	return xReturn;
}
Пример #13
0
static Void callback_ToHost(VirtQueue_Handle vq)
{
	UInt16 avail;
	int    i;
	Bool   doSwitch[portNUM_PROCESSORS];
	unsigned portBASE_TYPE curCpu =  portGetCurrentCPU();
	
	taskENTER_CRITICAL_NOT_RECURSIVE_FROM_ISR(&virtQueLock);

	if(listLIST_IS_EMPTY(&availBufList) != pdFALSE){
		taskEXIT_CRITICAL_NOT_RECURSIVE_FROM_ISR(&virtQueLock);
		return;
	}

	if((avail = GET_AVAIL_COUNT(vq)) == 0){
		taskEXIT_CRITICAL_NOT_RECURSIVE_FROM_ISR(&virtQueLock);
		return;
	}

	memset(doSwitch, FALSE, sizeof(doSwitch));

	do{
		signed portBASE_TYPE ret;

		/* Because this function is not an application code,             */
		/* there is not the problem with using xTaskRemoveFromEventList. */
		ret = xTaskRemoveFromEventList(&availBufList, pdFALSE);
		if(ret >= 0){
			doSwitch[ret] = TRUE;
		}			
	}
	while(--avail > 0);

	taskEXIT_CRITICAL_NOT_RECURSIVE_FROM_ISR(&virtQueLock);

	for(i = 0; i < portNUM_PROCESSORS; i++){
		if(doSwitch[i]){
			if(i == (int)curCpu){
				vPortYieldFromISR();
			}
			else{
				portINTERRUPT_CORE(i);
			}
		}
	}
}
Пример #14
0
static void prvCheckPendingReadyList( void )
{
    /* Are there any co-routines waiting to get moved to the ready list?  These
    are co-routines that have been readied by an ISR.  The ISR cannot access
    the	ready lists itself. */
    while ( listLIST_IS_EMPTY( &xPendingReadyCoRoutineList ) == pdFALSE ) {
        corCRCB *pxUnblockedCRCB;

        /* The pending ready list can be accessed by an ISR. */
        portDISABLE_INTERRUPTS();
        {
            pxUnblockedCRCB = ( corCRCB * ) listGET_OWNER_OF_HEAD_ENTRY( (&xPendingReadyCoRoutineList) );
            ( void ) uxListRemove( &( pxUnblockedCRCB->xEventListItem ) );
        }
        portENABLE_INTERRUPTS();

        ( void ) uxListRemove( &( pxUnblockedCRCB->xGenericListItem ) );
        prvAddCoRoutineToReadyQueue( pxUnblockedCRCB );
    }
}
Пример #15
0
signed portBASE_TYPE xQueueSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xTaskPreviouslyWoken )
{
	/* Similar to xQueueSend, except we don't block if there is no room in the
	queue.  Also we don't directly wake a task that was blocked on a queue
	read, instead we return a flag to say whether a context switch is required
	or not (i.e. has a task with a higher priority than us been woken by this
	post). */
	if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
	{
		prvCopyQueueData( pxQueue, pvItemToQueue );

		/* If the queue is locked we do not alter the event list.  This will
		be done when the queue is unlocked later. */
		if( pxQueue->xTxLock == queueUNLOCKED )
		{
			/* We only want to wake one task per ISR, so check that a task has
			not already been woken. */
			if( !xTaskPreviouslyWoken )		
			{
				if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
					{
						/* The task waiting has a higher priority so record that a
						context	switch is required. */
						return pdTRUE;
					}
				}
			}
		}
		else
		{
			/* Increment the lock count so the task that unlocks the queue
			knows that data was posted while it was locked. */
			++( pxQueue->xTxLock );
		}
	}

	return xTaskPreviouslyWoken;
}
Пример #16
0
signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxCoRoutineWoken )
{
signed portBASE_TYPE xReturn;

	/* We cannot block from an ISR, so check there is data available. If
	not then just leave without doing anything. */
	if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
	{
		/* Copy the data from the queue. */
		pxQueue->pcReadFrom += pxQueue->uxItemSize;
		if( pxQueue->pcReadFrom >= pxQueue->pcTail )
		{
			pxQueue->pcReadFrom = pxQueue->pcHead;
		}
		--( pxQueue->uxMessagesWaiting );
		memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize );

		if( !( *pxCoRoutineWoken ) )
		{
			if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
			{
				if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
				{
					*pxCoRoutineWoken = pdTRUE;
				}
			}
		}

		xReturn = pdPASS;
	}
	else
	{
		xReturn = pdFAIL;
	}

	return xReturn;
}
Пример #17
0
signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken )
{
	/* Cannot block within an ISR so if there is no space on the queue then
	exit without doing anything. */
	if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
	{
		prvCopyQueueData( pxQueue, pvItemToQueue );

		/* We only want to wake one co-routine per ISR, so check that a 
		co-routine has not already been woken. */
		if( !xCoRoutinePreviouslyWoken )		
		{
			if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
			{
				if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
				{
					return pdTRUE;
				}
			}
		}
	}

	return xCoRoutinePreviouslyWoken;
}
Пример #18
0
static TickType_t prvGetNextExpireTime( BaseType_t * const pxListWasEmpty )
{
TickType_t xNextExpireTime;

	/* Timers are listed in expiry time order, with the head of the list
	referencing the task that will expire first.  Obtain the time at which
	the timer with the nearest expiry time will expire.  If there are no
	active timers then just set the next expire time to 0.  That will cause
	this task to unblock when the tick count overflows, at which point the
	timer lists will be switched and the next expiry time can be
	re-assessed.  */
	*pxListWasEmpty = listLIST_IS_EMPTY( pxCurrentTimerList );
	if( *pxListWasEmpty == pdFALSE )
	{
		xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
	}
	else
	{
		/* Ensure the task unblocks when the tick count rolls over. */
		xNextExpireTime = ( TickType_t ) 0U;
	}

	return xNextExpireTime;
}
Пример #19
0
signed portBASE_TYPE xMutexGive( xMutexHandle pxMutex, portBASE_TYPE Release )
{
    portENTER_CRITICAL( );
    if ( pxMutex->pxOwner != xTaskGetCurrentTaskHandle( ) )
    {
        portEXIT_CRITICAL( );
        return pdFALSE;
    }

    if ( Release )
        pxMutex->uxCount = 0;
    else
    {
        if ( --pxMutex->uxCount != 0 )
        {
            portEXIT_CRITICAL( );
            return pdFALSE;
        }
    }

    if( !listLIST_IS_EMPTY( &pxMutex->xTasksWaitingToTake ) )
    {
        pxMutex->pxOwner = (xTaskHandle) listGET_OWNER_OF_HEAD_ENTRY( ( &pxMutex->xTasksWaitingToTake ) );
        pxMutex->uxCount = 1;

        if( xTaskRemoveFromEventList( &pxMutex->xTasksWaitingToTake ) == pdTRUE )
            taskYIELD( );
    }
    else
    {
        pxMutex->pxOwner = NULL;
    }

    portEXIT_CRITICAL( );
    return pdTRUE;
}
Пример #20
0
signed portBASE_TYPE xQueueGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition )
{
signed portBASE_TYPE xReturn = pdTRUE;
xTimeOutType xTimeOut;

	do
	{
    	/* If xTicksToWait is zero then we are not going to block even
    	if there is no room in the queue to post. */
		if( xTicksToWait > ( portTickType ) 0 )
		{
			vTaskSuspendAll();
			prvLockQueue( pxQueue );

			if( xReturn == pdTRUE )
			{
				/* This is the first time through - we need to capture the
				time while the scheduler is locked to ensure we attempt to
				block at least once. */
				vTaskSetTimeOutState( &xTimeOut );
			}

			if( prvIsQueueFull( pxQueue ) )
			{
	    		/* Need to call xTaskCheckForTimeout again as time could
	    		have passed since it was last called if this is not the
	    		first time around this loop.  */
				if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
				{
					traceBLOCKING_ON_QUEUE_SEND( pxQueue );
					vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );

					/* Unlocking the queue means queue events can effect the
					event list.  It is possible	that interrupts occurring now
					remove this task from the event	list again - but as the
					scheduler is suspended the task will go onto the pending
					ready last instead of the actual ready list. */
					prvUnlockQueue( pxQueue );

					/* Resuming the scheduler will move tasks from the pending
					ready list into the ready list - so it is feasible that this
					task is already in a ready list before it yields - in which
					case the yield will not cause a context switch unless there
					is also a higher priority task in the pending ready list. */
					if( !xTaskResumeAll() )
					{
						taskYIELD();
					}
				}
				else
				{
					prvUnlockQueue( pxQueue );
					( void ) xTaskResumeAll();
				}
			}
			else
			{
    			/* The queue was not full so we can just unlock the
    			scheduler and queue again before carrying on. */
				prvUnlockQueue( pxQueue );
				( void ) xTaskResumeAll();
			}
		}

  		/* Higher priority tasks and interrupts can execute during
  		this time and could possible refill the queue - even if we
  		unblocked because space became available. */

		taskENTER_CRITICAL();
		{
  			/* Is there room on the queue now?  To be running we must be
  			the highest priority task wanting to access the queue. */
			if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
			{
				traceQUEUE_SEND( pxQueue );
				prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
				xReturn = pdPASS;

				/* If there was a task waiting for data to arrive on the
				queue then unblock it now. */
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
					{
					    /* The unblocked task has a priority higher than
					    our own so yield immediately. */
					    taskYIELD();
					}
				}
			}
			else
			{
  				/* Setting xReturn to errQUEUE_FULL will force its timeout
  				to be re-evaluated.  This is necessary in case interrupts
  				and higher priority tasks accessed the queue between this
  				task being unblocked and subsequently attempting to write
  				to the queue. */
				xReturn = errQUEUE_FULL;
			}
		}
		taskEXIT_CRITICAL();

		if( xReturn == errQUEUE_FULL )
		{
			if( xTicksToWait > ( portTickType ) 0 )
			{
				if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
				{
					xReturn = queueERRONEOUS_UNBLOCK;
				}
				else
				{
					traceQUEUE_SEND_FAILED( pxQueue );
				}
			}
			else
			{
				traceQUEUE_SEND_FAILED( pxQueue );
			}
		}
	}
	while( xReturn == queueERRONEOUS_UNBLOCK );

	return xReturn;
}
Пример #21
0
signed portBASE_TYPE xQueueCRReceive( xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait )
{
signed portBASE_TYPE xReturn;

	/* If the queue is already empty we may have to block.  A critical section
	is required to prevent an interrupt adding something to the queue 
	between the check to see if the queue is empty and blocking on the queue. */
	portDISABLE_INTERRUPTS();
	{
		if( prvIsQueueEmpty( pxQueue ) )
		{
			/* There are no messages in the queue, do we want to block or just
			leave with nothing? */			
			if( xTicksToWait > ( portTickType ) 0 )
			{
				/* As this is a co-routine we cannot block directly, but return
				indicating that we need to block. */
				vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) );
				portENABLE_INTERRUPTS();
				return errQUEUE_BLOCKED;
			}
			else
			{
				portENABLE_INTERRUPTS();
				return errQUEUE_FULL;
			}
		}
	}
	portENABLE_INTERRUPTS();

	portNOP();

	portDISABLE_INTERRUPTS();
	{
		if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
		{
			/* Data is available from the queue. */
			pxQueue->pcReadFrom += pxQueue->uxItemSize;
			if( pxQueue->pcReadFrom >= pxQueue->pcTail )
			{
				pxQueue->pcReadFrom = pxQueue->pcHead;
			}
			--( pxQueue->uxMessagesWaiting );
			memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize );

			xReturn = pdPASS;

			/* Were any co-routines waiting for space to become available? */
			if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
			{
				/* In this instance the co-routine could be placed directly 
				into the ready list as we are within a critical section.  
				Instead the same pending ready list mechansim is used as if
				the event were caused from within an interrupt. */
				if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
				{
					xReturn = errQUEUE_YIELD;
				}
			}	
		}
		else
		{
			xReturn = pdFAIL;
		}
	}
	portENABLE_INTERRUPTS();

	return xReturn;
}
Пример #22
0
signed portBASE_TYPE xQueueCRSend( xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait )
{
signed portBASE_TYPE xReturn;
		
	/* If the queue is already full we may have to block.  A critical section
	is required to prevent an interrupt removing something from the queue 
	between the check to see if the queue is full and blocking on the queue. */
	portDISABLE_INTERRUPTS();
	{
		if( prvIsQueueFull( pxQueue ) )
		{
			/* The queue is full - do we want to block or just leave without
			posting? */
			if( xTicksToWait > ( portTickType ) 0 )
			{
				/* As this is called from a coroutine we cannot block directly, but
				return indicating that we need to block. */
				vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) );				
				portENABLE_INTERRUPTS();
				return errQUEUE_BLOCKED;
			}
			else
			{
				portENABLE_INTERRUPTS();
				return errQUEUE_FULL;
			}
		}
	}
	portENABLE_INTERRUPTS();
		
	portNOP();

	portDISABLE_INTERRUPTS();
	{
		if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
		{
			/* There is room in the queue, copy the data into the queue. */			
			prvCopyQueueData( pxQueue, pvItemToQueue );		
			xReturn = pdPASS;

			/* Were any co-routines waiting for data to become available? */
			if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
			{
				/* In this instance the co-routine could be placed directly 
				into the ready list as we are within a critical section.  
				Instead the same pending ready list mechansim is used as if
				the event were caused from within an interrupt. */
				if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
				{
					/* The co-routine waiting has a higher priority so record 
					that a yield might be appropriate. */
					xReturn = errQUEUE_YIELD;
				}
			}
		}
		else
		{
			xReturn = errQUEUE_FULL;
		}
	}
	portENABLE_INTERRUPTS();

	return xReturn;
}
Пример #23
0
signed portBASE_TYPE xQueueGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking )
{
signed portBASE_TYPE xReturn = pdTRUE;
xTimeOutType xTimeOut;
signed portCHAR *pcOriginalReadPosition;

	do
	{
		/* If there are no messages in the queue we may have to block. */
		if( xTicksToWait > ( portTickType ) 0 )
		{
			vTaskSuspendAll();
			prvLockQueue( pxQueue );

			if( xReturn == pdTRUE )
			{
				/* This is the first time through - we need to capture the
				time while the scheduler is locked to ensure we attempt to
				block at least once. */
				vTaskSetTimeOutState( &xTimeOut );
			}

			if( prvIsQueueEmpty( pxQueue ) )
			{
	    		/* Need to call xTaskCheckForTimeout again as time could
	    		have passed since it was last called if this is not the
	    		first time around this loop. */
				if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
				{
					traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );

					#if ( configUSE_MUTEXES == 1 )
					{
						if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
						{
							portENTER_CRITICAL();
								vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );
							portEXIT_CRITICAL();
						}
					}
					#endif

					vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
					prvUnlockQueue( pxQueue );
					if( !xTaskResumeAll() )
					{
						taskYIELD();
					}
				}
				else
				{
					prvUnlockQueue( pxQueue );
					( void ) xTaskResumeAll();
				}
			}
			else
			{
				prvUnlockQueue( pxQueue );
				( void ) xTaskResumeAll();
			}
		}

/* The two tasks are blocked on the queue, the low priority task is polling/running. */

/* An interrupt occurs here - which unblocks the HP tasks, but they do not run. */
		taskENTER_CRITICAL();
		{
/* Because the interrupt occurred the LP task manages to grab the data as the other two tasks are not yet running. */
			if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
			{
				/* Remember our read position in case we are just peeking. */
				pcOriginalReadPosition = pxQueue->pcReadFrom;

				prvCopyDataFromQueue( pxQueue, pvBuffer );

				if( xJustPeeking == pdFALSE )
				{
					traceQUEUE_RECEIVE( pxQueue );

					/* We are actually removing data. */
					--( pxQueue->uxMessagesWaiting );

					#if ( configUSE_MUTEXES == 1 )
					{
						if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
						{
							/* Record the information required to implement
							priority inheritance should it become necessary. */
							pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle();
						}
					}
					#endif

					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
						{
							taskYIELD();
						}
					}
				}
				else
				{
					traceQUEUE_PEEK( pxQueue );

					/* We are not removing the data, so reset our read
					pointer. */
					pxQueue->pcReadFrom = pcOriginalReadPosition;

					/* The data is being left in the queue, so see if there are
					any other tasks waiting for the data. */
					if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
					{
						/* Tasks that are removed from the event list will get added to
						the pending ready list as the scheduler is still suspended. */
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
						{
							/* The task waiting has a higher priority than this task. */
							taskYIELD();
						}
					}

				}

				xReturn = pdPASS;
			}
			else
			{
				xReturn = errQUEUE_EMPTY;
			}
		}
		taskEXIT_CRITICAL();

		if( xReturn == errQUEUE_EMPTY )
		{
			if( xTicksToWait > ( portTickType ) 0 )
			{
				if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
				{
					xReturn = queueERRONEOUS_UNBLOCK;
				}
				else
				{
					traceQUEUE_RECEIVE_FAILED( pxQueue );
				}
			}
			else
			{
				traceQUEUE_RECEIVE_FAILED( pxQueue );
			}
		}

	} while( xReturn == queueERRONEOUS_UNBLOCK );

	return xReturn;
}
Пример #24
0
	signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking )
	{
	signed portBASE_TYPE xReturn = pdTRUE;
	xTimeOutType xTimeOut;
	signed portCHAR *pcOriginalReadPosition;

		/* The source code that implements the alternative (Alt) API is
		simpler	because it makes more use of critical sections.  This is
		the approach taken by many other RTOSes, but FreeRTOS.org has the
		preferred fully featured API too.  The fully featured API has more
		complex	code that takes longer to execute, but makes less use of
		critical sections.  */

		do
		{
			/* If there are no messages in the queue we may have to block. */
			if( xTicksToWait > ( portTickType ) 0 )
			{
				portENTER_CRITICAL();
				{
					if( xReturn == pdPASS )
					{
						/* This is the first time through - capture the time
						inside the critical section to ensure we attempt to
						block at least once. */
						vTaskSetTimeOutState( &xTimeOut );
					}

					if( prvIsQueueEmpty( pxQueue ) )
					{
	    				/* Need to call xTaskCheckForTimeout again as time could
	    				have passed since it was last called if this is not the
	    				first time around this loop. */
						if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
						{
							traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );

							#if ( configUSE_MUTEXES == 1 )
							{
								if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
								{
									vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );
								}
							}
							#endif

							vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
							taskYIELD();
						}
					}
				}
				portEXIT_CRITICAL();
			}

			taskENTER_CRITICAL();
			{
				if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
				{
					/* Remember our read position in case we are just peeking. */
					pcOriginalReadPosition = pxQueue->pcReadFrom;

					prvCopyDataFromQueue( pxQueue, pvBuffer );

					if( xJustPeeking == pdFALSE )
					{
						traceQUEUE_RECEIVE( pxQueue );

						/* We are actually removing data. */
						--( pxQueue->uxMessagesWaiting );

						#if ( configUSE_MUTEXES == 1 )
						{
							if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
							{
								/* Record the information required to implement
								priority inheritance should it become necessary. */
								pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle();
							}
						}
						#endif

						if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
						{
							if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
							{
								taskYIELD();
							}
						}
					}
					else
					{
						traceQUEUE_PEEK( pxQueue );

						/* We are not removing the data, so reset our read
						pointer. */
						pxQueue->pcReadFrom = pcOriginalReadPosition;

						/* The data is being left in the queue, so see if there are
						any other tasks waiting for the data. */
						if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
						{
							/* Tasks that are removed from the event list will get added to
							the pending ready list as the scheduler is still suspended. */
							if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
							{
								/* The task waiting has a higher priority that this task. */
								taskYIELD();
							}
						}

					}

					xReturn = pdPASS;
				}
				else
				{
					xReturn = errQUEUE_EMPTY;
				}
			}
			taskEXIT_CRITICAL();

			if( xReturn == errQUEUE_EMPTY )
			{
				if( xTicksToWait > ( portTickType ) 0 )
				{
					if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
					{
						xReturn = queueERRONEOUS_UNBLOCK;
					}
					else
					{
						traceQUEUE_RECEIVE_FAILED( pxQueue );
					}
				}
				else
				{
					traceQUEUE_RECEIVE_FAILED( pxQueue );
				}
			}
		} while( xReturn == queueERRONEOUS_UNBLOCK );

		return xReturn;
	}
Пример #25
0
	signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition )
	{
	signed portBASE_TYPE xReturn = pdPASS;
	xTimeOutType xTimeOut;

		/* The source code that implements the alternative (Alt) API is
		simpler	because it makes more use of critical sections.  This is
		the approach taken by many other RTOSes, but FreeRTOS.org has the
		preferred fully featured API too.  The fully featured API has more
		complex	code that takes longer to execute, but makes less use of
		critical sections.  */

		do
		{
    		/* If xTicksToWait is zero then we are not going to block even
    		if there is no room in the queue to post. */
			if( xTicksToWait > ( portTickType ) 0 )
			{
				portENTER_CRITICAL();
				{
					if( xReturn == pdPASS )
					{
						/* This is the first time through - capture the time
						inside the critical section to ensure we attempt to
						block at least once. */
						vTaskSetTimeOutState( &xTimeOut );
					}

					if( prvIsQueueFull( pxQueue ) )
					{
	    				/* Need to call xTaskCheckForTimeout again as time could
	    				have passed since it was last called if this is not the
	    				first time around this loop.  */
						if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
						{
							traceBLOCKING_ON_QUEUE_SEND( pxQueue );
							vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );

							/* This will exit the critical section, then re-enter when
							the task next runs. */
							taskYIELD();
						}
					}
				}
				portEXIT_CRITICAL();
			}

   			/* Higher priority tasks and interrupts can execute during
   			this time and could possible refill the queue - even if we
   			unblocked because space became available. */

			taskENTER_CRITICAL();
			{
   				/* Is there room on the queue now?  To be running we must be
   				the highest priority task wanting to access the queue. */
				if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
				{
					traceQUEUE_SEND( pxQueue );
					prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
					xReturn = pdPASS;

					/* If there was a task waiting for data to arrive on the
					queue then unblock it now. */
					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
						{
							/* The unblocked task has a priority higher than
							our own so yield immediately. */
							taskYIELD();
						}
					}
				}
				else
				{
   					/* Setting xReturn to errQUEUE_FULL will force its timeout
   					to be re-evaluated.  This is necessary in case interrupts
   					and higher priority tasks accessed the queue between this
   					task being unblocked and subsequently attempting to write
   					to the queue. */
					xReturn = errQUEUE_FULL;
				}
			}
			taskEXIT_CRITICAL();

			if( xReturn == errQUEUE_FULL )
			{
				if( xTicksToWait > ( portTickType ) 0 )
				{
					if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
					{
						xReturn = queueERRONEOUS_UNBLOCK;
					}
					else
					{
						traceQUEUE_SEND_FAILED( pxQueue );
					}
				}
				else
				{
					traceQUEUE_SEND_FAILED( pxQueue );
				}
			}
		}
		while( xReturn == queueERRONEOUS_UNBLOCK );

		return xReturn;
	}