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/*
FreeRTOS V9.0.1 - Copyright (C) 2017 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
This file is part of the FreeRTOS distribution.
FreeRTOS is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License (version 2) as published by the
Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception.
***************************************************************************
>>! NOTE: The modification to the GPL is included to allow you to !<<
>>! distribute a combined work that includes FreeRTOS without being !<<
>>! obliged to provide the source code for proprietary components !<<
>>! outside of the FreeRTOS kernel. !<<
***************************************************************************
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. Full license text is available on the following
link: http://www.freertos.org/a00114.html
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that is more than just the market leader, it *
* is the industry's de facto standard. *
* *
* Help yourself get started quickly while simultaneously helping *
* to support the FreeRTOS project by purchasing a FreeRTOS *
* tutorial book, reference manual, or both: *
* http://www.FreeRTOS.org/Documentation *
* *
***************************************************************************
http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading
the FAQ page "My application does not run, what could be wrong?". Have you
defined configASSERT()?
http://www.FreeRTOS.org/support - In return for receiving this top quality
embedded software for free we request you assist our global community by
participating in the support forum.
http://www.FreeRTOS.org/training - Investing in training allows your team to
be as productive as possible as early as possible. Now you can receive
FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
Ltd, and the world's leading authority on the world's leading RTOS.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.
http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and commercial middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
/*
* Creates six tasks that operate on three queues as follows:
*
* The first two tasks send and receive an incrementing number to/from a queue.
* One task acts as a producer and the other as the consumer. The consumer is a
* higher priority than the producer and is set to block on queue reads. The queue
* only has space for one item - as soon as the producer posts a message on the
* queue the consumer will unblock, pre-empt the producer, and remove the item.
*
* The second two tasks work the other way around. Again the queue used only has
* enough space for one item. This time the consumer has a lower priority than the
* producer. The producer will try to post on the queue blocking when the queue is
* full. When the consumer wakes it will remove the item from the queue, causing
* the producer to unblock, pre-empt the consumer, and immediately re-fill the
* queue.
*
* The last two tasks use the same queue producer and consumer functions. This time the queue has
* enough space for lots of items and the tasks operate at the same priority. The
* producer will execute, placing items into the queue. The consumer will start
* executing when either the queue becomes full (causing the producer to block) or
* a context switch occurs (tasks of the same priority will time slice).
*
*/
#include <stdlib.h>
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
/* Demo program include files. */
#include "BlockQ.h"
#define blckqSTACK_SIZE configMINIMAL_STACK_SIZE
#define blckqNUM_TASK_SETS ( 3 )
#if( configSUPPORT_DYNAMIC_ALLOCATION == 0 )
#error This example cannot be used if dynamic allocation is not allowed.
#endif
/* Structure used to pass parameters to the blocking queue tasks. */
typedef struct BLOCKING_QUEUE_PARAMETERS
{
QueueHandle_t xQueue; /*< The queue to be used by the task. */
TickType_t xBlockTime; /*< The block time to use on queue reads/writes. */
volatile short *psCheckVariable; /*< Incremented on each successful cycle to check the task is still running. */
} xBlockingQueueParameters;
/* Task function that creates an incrementing number and posts it on a queue. */
static portTASK_FUNCTION_PROTO( vBlockingQueueProducer, pvParameters );
/* Task function that removes the incrementing number from a queue and checks that
it is the expected number. */
static portTASK_FUNCTION_PROTO( vBlockingQueueConsumer, pvParameters );
/* Variables which are incremented each time an item is removed from a queue, and
found to be the expected value.
These are used to check that the tasks are still running. */
static volatile short sBlockingConsumerCount[ blckqNUM_TASK_SETS ] = { ( uint16_t ) 0, ( uint16_t ) 0, ( uint16_t ) 0 };
/* Variable which are incremented each time an item is posted on a queue. These
are used to check that the tasks are still running. */
static volatile short sBlockingProducerCount[ blckqNUM_TASK_SETS ] = { ( uint16_t ) 0, ( uint16_t ) 0, ( uint16_t ) 0 };
/*-----------------------------------------------------------*/
void vStartBlockingQueueTasks( UBaseType_t uxPriority )
{
xBlockingQueueParameters *pxQueueParameters1, *pxQueueParameters2;
xBlockingQueueParameters *pxQueueParameters3, *pxQueueParameters4;
xBlockingQueueParameters *pxQueueParameters5, *pxQueueParameters6;
const UBaseType_t uxQueueSize1 = 1, uxQueueSize5 = 5;
const TickType_t xBlockTime = pdMS_TO_TICKS( ( TickType_t ) 1000 );
const TickType_t xDontBlock = ( TickType_t ) 0;
/* Create the first two tasks as described at the top of the file. */
/* First create the structure used to pass parameters to the consumer tasks. */
pxQueueParameters1 = ( xBlockingQueueParameters * ) pvPortMalloc( sizeof( xBlockingQueueParameters ) );
/* Create the queue used by the first two tasks to pass the incrementing number.
Pass a pointer to the queue in the parameter structure. */
pxQueueParameters1->xQueue = xQueueCreate( uxQueueSize1, ( UBaseType_t ) sizeof( uint16_t ) );
/* The consumer is created first so gets a block time as described above. */
pxQueueParameters1->xBlockTime = xBlockTime;
/* Pass in the variable that this task is going to increment so we can check it
is still running. */
pxQueueParameters1->psCheckVariable = &( sBlockingConsumerCount[ 0 ] );
/* Create the structure used to pass parameters to the producer task. */
pxQueueParameters2 = ( xBlockingQueueParameters * ) pvPortMalloc( sizeof( xBlockingQueueParameters ) );
/* Pass the queue to this task also, using the parameter structure. */
pxQueueParameters2->xQueue = pxQueueParameters1->xQueue;
/* The producer is not going to block - as soon as it posts the consumer will
wake and remove the item so the producer should always have room to post. */
pxQueueParameters2->xBlockTime = xDontBlock;
/* Pass in the variable that this task is going to increment so we can check
it is still running. */
pxQueueParameters2->psCheckVariable = &( sBlockingProducerCount[ 0 ] );
/* Note the producer has a lower priority than the consumer when the tasks are
spawned. */
xTaskCreate( vBlockingQueueConsumer, "QConsB1", blckqSTACK_SIZE, ( void * ) pxQueueParameters1, uxPriority, NULL );
xTaskCreate( vBlockingQueueProducer, "QProdB2", blckqSTACK_SIZE, ( void * ) pxQueueParameters2, tskIDLE_PRIORITY, NULL );
/* Create the second two tasks as described at the top of the file. This uses
the same mechanism but reverses the task priorities. */
pxQueueParameters3 = ( xBlockingQueueParameters * ) pvPortMalloc( sizeof( xBlockingQueueParameters ) );
pxQueueParameters3->xQueue = xQueueCreate( uxQueueSize1, ( UBaseType_t ) sizeof( uint16_t ) );
pxQueueParameters3->xBlockTime = xDontBlock;
pxQueueParameters3->psCheckVariable = &( sBlockingProducerCount[ 1 ] );
pxQueueParameters4 = ( xBlockingQueueParameters * ) pvPortMalloc( sizeof( xBlockingQueueParameters ) );
pxQueueParameters4->xQueue = pxQueueParameters3->xQueue;
pxQueueParameters4->xBlockTime = xBlockTime;
pxQueueParameters4->psCheckVariable = &( sBlockingConsumerCount[ 1 ] );
xTaskCreate( vBlockingQueueConsumer, "QConsB3", blckqSTACK_SIZE, ( void * ) pxQueueParameters3, tskIDLE_PRIORITY, NULL );
xTaskCreate( vBlockingQueueProducer, "QProdB4", blckqSTACK_SIZE, ( void * ) pxQueueParameters4, uxPriority, NULL );
/* Create the last two tasks as described above. The mechanism is again just
the same. This time both parameter structures are given a block time. */
pxQueueParameters5 = ( xBlockingQueueParameters * ) pvPortMalloc( sizeof( xBlockingQueueParameters ) );
pxQueueParameters5->xQueue = xQueueCreate( uxQueueSize5, ( UBaseType_t ) sizeof( uint16_t ) );
pxQueueParameters5->xBlockTime = xBlockTime;
pxQueueParameters5->psCheckVariable = &( sBlockingProducerCount[ 2 ] );
pxQueueParameters6 = ( xBlockingQueueParameters * ) pvPortMalloc( sizeof( xBlockingQueueParameters ) );
pxQueueParameters6->xQueue = pxQueueParameters5->xQueue;
pxQueueParameters6->xBlockTime = xBlockTime;
pxQueueParameters6->psCheckVariable = &( sBlockingConsumerCount[ 2 ] );
xTaskCreate( vBlockingQueueProducer, "QProdB5", blckqSTACK_SIZE, ( void * ) pxQueueParameters5, tskIDLE_PRIORITY, NULL );
xTaskCreate( vBlockingQueueConsumer, "QConsB6", blckqSTACK_SIZE, ( void * ) pxQueueParameters6, tskIDLE_PRIORITY, NULL );
}
/*-----------------------------------------------------------*/
static portTASK_FUNCTION( vBlockingQueueProducer, pvParameters )
{
uint16_t usValue = 0;
xBlockingQueueParameters *pxQueueParameters;
short sErrorEverOccurred = pdFALSE;
pxQueueParameters = ( xBlockingQueueParameters * ) pvParameters;
for( ;; )
{
if( xQueueSend( pxQueueParameters->xQueue, ( void * ) &usValue, pxQueueParameters->xBlockTime ) != pdPASS )
{
sErrorEverOccurred = pdTRUE;
}
else
{
/* We have successfully posted a message, so increment the variable
used to check we are still running. */
if( sErrorEverOccurred == pdFALSE )
{
( *pxQueueParameters->psCheckVariable )++;
}
/* Increment the variable we are going to post next time round. The
consumer will expect the numbers to follow in numerical order. */
++usValue;
#if configUSE_PREEMPTION == 0
taskYIELD();
#endif
}
}
}
/*-----------------------------------------------------------*/
static portTASK_FUNCTION( vBlockingQueueConsumer, pvParameters )
{
uint16_t usData, usExpectedValue = 0;
xBlockingQueueParameters *pxQueueParameters;
short sErrorEverOccurred = pdFALSE;
pxQueueParameters = ( xBlockingQueueParameters * ) pvParameters;
for( ;; )
{
if( xQueueReceive( pxQueueParameters->xQueue, &usData, pxQueueParameters->xBlockTime ) == pdPASS )
{
if( usData != usExpectedValue )
{
/* Catch-up. */
usExpectedValue = usData;
sErrorEverOccurred = pdTRUE;
}
else
{
/* We have successfully received a message, so increment the
variable used to check we are still running. */
if( sErrorEverOccurred == pdFALSE )
{
( *pxQueueParameters->psCheckVariable )++;
}
/* Increment the value we expect to remove from the queue next time
round. */
++usExpectedValue;
}
#if configUSE_PREEMPTION == 0
{
if( pxQueueParameters->xBlockTime == 0 )
{
taskYIELD();
}
}
#endif
}
}
}
/*-----------------------------------------------------------*/
/* This is called to check that all the created tasks are still running. */
BaseType_t xAreBlockingQueuesStillRunning( void )
{
static short sLastBlockingConsumerCount[ blckqNUM_TASK_SETS ] = { ( uint16_t ) 0, ( uint16_t ) 0, ( uint16_t ) 0 };
static short sLastBlockingProducerCount[ blckqNUM_TASK_SETS ] = { ( uint16_t ) 0, ( uint16_t ) 0, ( uint16_t ) 0 };
BaseType_t xReturn = pdPASS, xTasks;
/* Not too worried about mutual exclusion on these variables as they are 16
bits and we are only reading them. We also only care to see if they have
changed or not.
Loop through each check variable to and return pdFALSE if any are found not
to have changed since the last call. */
for( xTasks = 0; xTasks < blckqNUM_TASK_SETS; xTasks++ )
{
if( sBlockingConsumerCount[ xTasks ] == sLastBlockingConsumerCount[ xTasks ] )
{
xReturn = pdFALSE;
}
sLastBlockingConsumerCount[ xTasks ] = sBlockingConsumerCount[ xTasks ];
if( sBlockingProducerCount[ xTasks ] == sLastBlockingProducerCount[ xTasks ] )
{
xReturn = pdFALSE;
}
sLastBlockingProducerCount[ xTasks ] = sBlockingProducerCount[ xTasks ];
}
return xReturn;
}
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