mirror of
https://github.com/FreeRTOS/FreeRTOS-Kernel.git
synced 2025-08-13 14:48:33 -04:00
Add volatile qualifier to loop counters used to detect stalled tasks.
This commit is contained in:
Richard Barry
parent
bea704342a
commit
b19ede773a
5 changed files with 1967 additions and 1967 deletions
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@ -1,414 +1,414 @@
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/*
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FreeRTOS.org V5.0.0 - Copyright (C) 2003-2008 Richard Barry.
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This file is part of the FreeRTOS.org distribution.
|
||||
|
||||
FreeRTOS.org is free software; you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation; either version 2 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
FreeRTOS.org 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. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with FreeRTOS.org; if not, write to the Free Software
|
||||
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
|
||||
A special exception to the GPL can be applied should you wish to distribute
|
||||
a combined work that includes FreeRTOS.org, without being obliged to provide
|
||||
the source code for any proprietary components. See the licensing section
|
||||
of http://www.FreeRTOS.org for full details of how and when the exception
|
||||
can be applied.
|
||||
|
||||
***************************************************************************
|
||||
***************************************************************************
|
||||
* *
|
||||
* SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, *
|
||||
* and even write all or part of your application on your behalf. *
|
||||
* See http://www.OpenRTOS.com for details of the services we provide to *
|
||||
* expedite your project. *
|
||||
* *
|
||||
***************************************************************************
|
||||
***************************************************************************
|
||||
|
||||
Please ensure to read the configuration and relevant port sections of the
|
||||
online documentation.
|
||||
|
||||
http://www.FreeRTOS.org - Documentation, latest information, license and
|
||||
contact details.
|
||||
|
||||
http://www.SafeRTOS.com - A version that is certified for use in safety
|
||||
critical systems.
|
||||
|
||||
http://www.OpenRTOS.com - Commercial support, development, porting,
|
||||
licensing and training services.
|
||||
*/
|
||||
|
||||
/*
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* The first test creates three tasks - two counter tasks (one continuous count
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* and one limited count) and one controller. A "count" variable is shared
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* between all three tasks. The two counter tasks should never be in a "ready"
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* state at the same time. The controller task runs at the same priority as
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* the continuous count task, and at a lower priority than the limited count
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* task.
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*
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* One counter task loops indefinitely, incrementing the shared count variable
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* on each iteration. To ensure it has exclusive access to the variable it
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* raises it's priority above that of the controller task before each
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* increment, lowering it again to it's original priority before starting the
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* next iteration.
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*
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* The other counter task increments the shared count variable on each
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* iteration of it's loop until the count has reached a limit of 0xff - at
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* which point it suspends itself. It will not start a new loop until the
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* controller task has made it "ready" again by calling vTaskResume ().
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* This second counter task operates at a higher priority than controller
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* task so does not need to worry about mutual exclusion of the counter
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* variable.
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*
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* The controller task is in two sections. The first section controls and
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* monitors the continuous count task. When this section is operational the
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* limited count task is suspended. Likewise, the second section controls
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* and monitors the limited count task. When this section is operational the
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* continuous count task is suspended.
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*
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* In the first section the controller task first takes a copy of the shared
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* count variable. To ensure mutual exclusion on the count variable it
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* suspends the continuous count task, resuming it again when the copy has been
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* taken. The controller task then sleeps for a fixed period - during which
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* the continuous count task will execute and increment the shared variable.
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* When the controller task wakes it checks that the continuous count task
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* has executed by comparing the copy of the shared variable with its current
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* value. This time, to ensure mutual exclusion, the scheduler itself is
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* suspended with a call to vTaskSuspendAll (). This is for demonstration
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* purposes only and is not a recommended technique due to its inefficiency.
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*
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* After a fixed number of iterations the controller task suspends the
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* continuous count task, and moves on to its second section.
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*
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* At the start of the second section the shared variable is cleared to zero.
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* The limited count task is then woken from it's suspension by a call to
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* vTaskResume (). As this counter task operates at a higher priority than
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* the controller task the controller task should not run again until the
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* shared variable has been counted up to the limited value causing the counter
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* task to suspend itself. The next line after vTaskResume () is therefore
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* a check on the shared variable to ensure everything is as expected.
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*
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*
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* The second test consists of a couple of very simple tasks that post onto a
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* queue while the scheduler is suspended. This test was added to test parts
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* of the scheduler not exercised by the first test.
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*
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*/
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#include <stdlib.h>
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/* Scheduler include files. */
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#include "FreeRTOS.h"
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#include "task.h"
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#include "semphr.h"
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/* Demo app include files. */
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#include "dynamic.h"
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/* Function that implements the "limited count" task as described above. */
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static portTASK_FUNCTION_PROTO( vLimitedIncrementTask, pvParameters );
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/* Function that implements the "continuous count" task as described above. */
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static portTASK_FUNCTION_PROTO( vContinuousIncrementTask, pvParameters );
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/* Function that implements the controller task as described above. */
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static portTASK_FUNCTION_PROTO( vCounterControlTask, pvParameters );
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static portTASK_FUNCTION_PROTO( vQueueReceiveWhenSuspendedTask, pvParameters );
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static portTASK_FUNCTION_PROTO( vQueueSendWhenSuspendedTask, pvParameters );
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/* Demo task specific constants. */
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#define priSTACK_SIZE ( configMINIMAL_STACK_SIZE )
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#define priSLEEP_TIME ( ( portTickType ) 128 / portTICK_RATE_MS )
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#define priLOOPS ( 5 )
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#define priMAX_COUNT ( ( unsigned portLONG ) 0xff )
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#define priNO_BLOCK ( ( portTickType ) 0 )
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#define priSUSPENDED_QUEUE_LENGTH ( 1 )
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/*-----------------------------------------------------------*/
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/* Handles to the two counter tasks. These could be passed in as parameters
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to the controller task to prevent them having to be file scope. */
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static xTaskHandle xContinousIncrementHandle, xLimitedIncrementHandle;
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/* The shared counter variable. This is passed in as a parameter to the two
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counter variables for demonstration purposes. */
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static unsigned portLONG ulCounter;
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/* Variables used to check that the tasks are still operating without error.
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Each complete iteration of the controller task increments this variable
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provided no errors have been found. The variable maintaining the same value
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is therefore indication of an error. */
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static unsigned portSHORT usCheckVariable = ( unsigned portSHORT ) 0;
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static portBASE_TYPE xSuspendedQueueSendError = pdFALSE;
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static portBASE_TYPE xSuspendedQueueReceiveError = pdFALSE;
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/* Queue used by the second test. */
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xQueueHandle xSuspendedTestQueue;
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/*-----------------------------------------------------------*/
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/*
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* Start the three tasks as described at the top of the file.
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* Note that the limited count task is given a higher priority.
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*/
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void vStartDynamicPriorityTasks( void )
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{
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xSuspendedTestQueue = xQueueCreate( priSUSPENDED_QUEUE_LENGTH, sizeof( unsigned portLONG ) );
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xTaskCreate( vContinuousIncrementTask, ( signed portCHAR * ) "CNT_INC", priSTACK_SIZE, ( void * ) &ulCounter, tskIDLE_PRIORITY, &xContinousIncrementHandle );
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xTaskCreate( vLimitedIncrementTask, ( signed portCHAR * ) "LIM_INC", priSTACK_SIZE, ( void * ) &ulCounter, tskIDLE_PRIORITY + 1, &xLimitedIncrementHandle );
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xTaskCreate( vCounterControlTask, ( signed portCHAR * ) "C_CTRL", priSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
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xTaskCreate( vQueueSendWhenSuspendedTask, ( signed portCHAR * ) "SUSP_TX", priSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
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xTaskCreate( vQueueReceiveWhenSuspendedTask, ( signed portCHAR * ) "SUSP_RX", priSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
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}
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/*-----------------------------------------------------------*/
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/*
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* Just loops around incrementing the shared variable until the limit has been
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* reached. Once the limit has been reached it suspends itself.
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*/
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static portTASK_FUNCTION( vLimitedIncrementTask, pvParameters )
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{
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unsigned portLONG *pulCounter;
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/* Take a pointer to the shared variable from the parameters passed into
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the task. */
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pulCounter = ( unsigned portLONG * ) pvParameters;
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/* This will run before the control task, so the first thing it does is
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suspend - the control task will resume it when ready. */
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vTaskSuspend( NULL );
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for( ;; )
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{
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/* Just count up to a value then suspend. */
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( *pulCounter )++;
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if( *pulCounter >= priMAX_COUNT )
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{
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vTaskSuspend( NULL );
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}
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}
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}
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/*-----------------------------------------------------------*/
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/*
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* Just keep counting the shared variable up. The control task will suspend
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* this task when it wants.
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*/
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static portTASK_FUNCTION( vContinuousIncrementTask, pvParameters )
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{
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unsigned portLONG *pulCounter;
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unsigned portBASE_TYPE uxOurPriority;
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/* Take a pointer to the shared variable from the parameters passed into
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the task. */
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pulCounter = ( unsigned portLONG * ) pvParameters;
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/* Query our priority so we can raise it when exclusive access to the
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shared variable is required. */
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uxOurPriority = uxTaskPriorityGet( NULL );
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for( ;; )
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{
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/* Raise our priority above the controller task to ensure a context
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switch does not occur while we are accessing this variable. */
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vTaskPrioritySet( NULL, uxOurPriority + 1 );
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( *pulCounter )++;
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vTaskPrioritySet( NULL, uxOurPriority );
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}
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}
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/*-----------------------------------------------------------*/
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/*
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* Controller task as described above.
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*/
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static portTASK_FUNCTION( vCounterControlTask, pvParameters )
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{
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unsigned portLONG ulLastCounter;
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portSHORT sLoops;
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portSHORT sError = pdFALSE;
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/* Just to stop warning messages. */
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( void ) pvParameters;
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for( ;; )
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{
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/* Start with the counter at zero. */
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ulCounter = ( unsigned portLONG ) 0;
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/* First section : */
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/* Check the continuous count task is running. */
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for( sLoops = 0; sLoops < priLOOPS; sLoops++ )
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{
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/* Suspend the continuous count task so we can take a mirror of the
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shared variable without risk of corruption. */
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vTaskSuspend( xContinousIncrementHandle );
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ulLastCounter = ulCounter;
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vTaskResume( xContinousIncrementHandle );
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/* Now delay to ensure the other task has processor time. */
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vTaskDelay( priSLEEP_TIME );
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/* Check the shared variable again. This time to ensure mutual
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exclusion the whole scheduler will be locked. This is just for
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demo purposes! */
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vTaskSuspendAll();
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{
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if( ulLastCounter == ulCounter )
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{
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/* The shared variable has not changed. There is a problem
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with the continuous count task so flag an error. */
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sError = pdTRUE;
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}
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}
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xTaskResumeAll();
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}
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/* Second section: */
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/* Suspend the continuous counter task so it stops accessing the shared variable. */
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vTaskSuspend( xContinousIncrementHandle );
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/* Reset the variable. */
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ulCounter = ( unsigned portLONG ) 0;
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/* Resume the limited count task which has a higher priority than us.
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We should therefore not return from this call until the limited count
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task has suspended itself with a known value in the counter variable. */
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vTaskResume( xLimitedIncrementHandle );
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/* Does the counter variable have the expected value? */
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if( ulCounter != priMAX_COUNT )
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{
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sError = pdTRUE;
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}
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if( sError == pdFALSE )
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{
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/* If no errors have occurred then increment the check variable. */
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portENTER_CRITICAL();
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usCheckVariable++;
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portEXIT_CRITICAL();
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}
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/* Resume the continuous count task and do it all again. */
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vTaskResume( xContinousIncrementHandle );
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}
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}
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/*-----------------------------------------------------------*/
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static portTASK_FUNCTION( vQueueSendWhenSuspendedTask, pvParameters )
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{
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static unsigned portLONG ulValueToSend = ( unsigned portLONG ) 0;
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/* Just to stop warning messages. */
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( void ) pvParameters;
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for( ;; )
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{
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vTaskSuspendAll();
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{
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/* We must not block while the scheduler is suspended! */
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if( xQueueSend( xSuspendedTestQueue, ( void * ) &ulValueToSend, priNO_BLOCK ) != pdTRUE )
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{
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xSuspendedQueueSendError = pdTRUE;
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}
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}
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xTaskResumeAll();
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vTaskDelay( priSLEEP_TIME );
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++ulValueToSend;
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}
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}
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/*-----------------------------------------------------------*/
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static portTASK_FUNCTION( vQueueReceiveWhenSuspendedTask, pvParameters )
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{
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static unsigned portLONG ulExpectedValue = ( unsigned portLONG ) 0, ulReceivedValue;
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portBASE_TYPE xGotValue;
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/* Just to stop warning messages. */
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( void ) pvParameters;
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for( ;; )
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{
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do
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{
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/* Suspending the scheduler here is fairly pointless and
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undesirable for a normal application. It is done here purely
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to test the scheduler. The inner xTaskResumeAll() should
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never return pdTRUE as the scheduler is still locked by the
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outer call. */
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vTaskSuspendAll();
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{
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vTaskSuspendAll();
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{
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xGotValue = xQueueReceive( xSuspendedTestQueue, ( void * ) &ulReceivedValue, priNO_BLOCK );
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}
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if( xTaskResumeAll() )
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{
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xSuspendedQueueReceiveError = pdTRUE;
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}
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}
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xTaskResumeAll();
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#if configUSE_PREEMPTION == 0
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{
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taskYIELD();
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}
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#endif
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} while( xGotValue == pdFALSE );
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if( ulReceivedValue != ulExpectedValue )
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{
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xSuspendedQueueReceiveError = pdTRUE;
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}
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++ulExpectedValue;
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}
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}
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/*-----------------------------------------------------------*/
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/* Called to check that all the created tasks are still running without error. */
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portBASE_TYPE xAreDynamicPriorityTasksStillRunning( void )
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{
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/* Keep a history of the check variables so we know if it has been incremented
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since the last call. */
|
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static unsigned portSHORT usLastTaskCheck = ( unsigned portSHORT ) 0;
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portBASE_TYPE xReturn = pdTRUE;
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/* Check the tasks are still running by ensuring the check variable
|
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is still incrementing. */
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if( usCheckVariable == usLastTaskCheck )
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{
|
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/* The check has not incremented so an error exists. */
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xReturn = pdFALSE;
|
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}
|
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|
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if( xSuspendedQueueSendError == pdTRUE )
|
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{
|
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xReturn = pdFALSE;
|
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}
|
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|
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if( xSuspendedQueueReceiveError == pdTRUE )
|
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{
|
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xReturn = pdFALSE;
|
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}
|
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|
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usLastTaskCheck = usCheckVariable;
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return xReturn;
|
||||
}
|
||||
/*
|
||||
FreeRTOS.org V5.0.0 - Copyright (C) 2003-2008 Richard Barry.
|
||||
|
||||
This file is part of the FreeRTOS.org distribution.
|
||||
|
||||
FreeRTOS.org is free software; you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation; either version 2 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
FreeRTOS.org 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. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with FreeRTOS.org; if not, write to the Free Software
|
||||
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
|
||||
A special exception to the GPL can be applied should you wish to distribute
|
||||
a combined work that includes FreeRTOS.org, without being obliged to provide
|
||||
the source code for any proprietary components. See the licensing section
|
||||
of http://www.FreeRTOS.org for full details of how and when the exception
|
||||
can be applied.
|
||||
|
||||
***************************************************************************
|
||||
***************************************************************************
|
||||
* *
|
||||
* SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, *
|
||||
* and even write all or part of your application on your behalf. *
|
||||
* See http://www.OpenRTOS.com for details of the services we provide to *
|
||||
* expedite your project. *
|
||||
* *
|
||||
***************************************************************************
|
||||
***************************************************************************
|
||||
|
||||
Please ensure to read the configuration and relevant port sections of the
|
||||
online documentation.
|
||||
|
||||
http://www.FreeRTOS.org - Documentation, latest information, license and
|
||||
contact details.
|
||||
|
||||
http://www.SafeRTOS.com - A version that is certified for use in safety
|
||||
critical systems.
|
||||
|
||||
http://www.OpenRTOS.com - Commercial support, development, porting,
|
||||
licensing and training services.
|
||||
*/
|
||||
|
||||
/*
|
||||
* The first test creates three tasks - two counter tasks (one continuous count
|
||||
* and one limited count) and one controller. A "count" variable is shared
|
||||
* between all three tasks. The two counter tasks should never be in a "ready"
|
||||
* state at the same time. The controller task runs at the same priority as
|
||||
* the continuous count task, and at a lower priority than the limited count
|
||||
* task.
|
||||
*
|
||||
* One counter task loops indefinitely, incrementing the shared count variable
|
||||
* on each iteration. To ensure it has exclusive access to the variable it
|
||||
* raises it's priority above that of the controller task before each
|
||||
* increment, lowering it again to it's original priority before starting the
|
||||
* next iteration.
|
||||
*
|
||||
* The other counter task increments the shared count variable on each
|
||||
* iteration of it's loop until the count has reached a limit of 0xff - at
|
||||
* which point it suspends itself. It will not start a new loop until the
|
||||
* controller task has made it "ready" again by calling vTaskResume ().
|
||||
* This second counter task operates at a higher priority than controller
|
||||
* task so does not need to worry about mutual exclusion of the counter
|
||||
* variable.
|
||||
*
|
||||
* The controller task is in two sections. The first section controls and
|
||||
* monitors the continuous count task. When this section is operational the
|
||||
* limited count task is suspended. Likewise, the second section controls
|
||||
* and monitors the limited count task. When this section is operational the
|
||||
* continuous count task is suspended.
|
||||
*
|
||||
* In the first section the controller task first takes a copy of the shared
|
||||
* count variable. To ensure mutual exclusion on the count variable it
|
||||
* suspends the continuous count task, resuming it again when the copy has been
|
||||
* taken. The controller task then sleeps for a fixed period - during which
|
||||
* the continuous count task will execute and increment the shared variable.
|
||||
* When the controller task wakes it checks that the continuous count task
|
||||
* has executed by comparing the copy of the shared variable with its current
|
||||
* value. This time, to ensure mutual exclusion, the scheduler itself is
|
||||
* suspended with a call to vTaskSuspendAll (). This is for demonstration
|
||||
* purposes only and is not a recommended technique due to its inefficiency.
|
||||
*
|
||||
* After a fixed number of iterations the controller task suspends the
|
||||
* continuous count task, and moves on to its second section.
|
||||
*
|
||||
* At the start of the second section the shared variable is cleared to zero.
|
||||
* The limited count task is then woken from it's suspension by a call to
|
||||
* vTaskResume (). As this counter task operates at a higher priority than
|
||||
* the controller task the controller task should not run again until the
|
||||
* shared variable has been counted up to the limited value causing the counter
|
||||
* task to suspend itself. The next line after vTaskResume () is therefore
|
||||
* a check on the shared variable to ensure everything is as expected.
|
||||
*
|
||||
*
|
||||
* The second test consists of a couple of very simple tasks that post onto a
|
||||
* queue while the scheduler is suspended. This test was added to test parts
|
||||
* of the scheduler not exercised by the first test.
|
||||
*
|
||||
*/
|
||||
|
||||
#include <stdlib.h>
|
||||
|
||||
/* Scheduler include files. */
|
||||
#include "FreeRTOS.h"
|
||||
#include "task.h"
|
||||
#include "semphr.h"
|
||||
|
||||
/* Demo app include files. */
|
||||
#include "dynamic.h"
|
||||
|
||||
/* Function that implements the "limited count" task as described above. */
|
||||
static portTASK_FUNCTION_PROTO( vLimitedIncrementTask, pvParameters );
|
||||
|
||||
/* Function that implements the "continuous count" task as described above. */
|
||||
static portTASK_FUNCTION_PROTO( vContinuousIncrementTask, pvParameters );
|
||||
|
||||
/* Function that implements the controller task as described above. */
|
||||
static portTASK_FUNCTION_PROTO( vCounterControlTask, pvParameters );
|
||||
|
||||
static portTASK_FUNCTION_PROTO( vQueueReceiveWhenSuspendedTask, pvParameters );
|
||||
static portTASK_FUNCTION_PROTO( vQueueSendWhenSuspendedTask, pvParameters );
|
||||
|
||||
/* Demo task specific constants. */
|
||||
#define priSTACK_SIZE ( configMINIMAL_STACK_SIZE )
|
||||
#define priSLEEP_TIME ( ( portTickType ) 128 / portTICK_RATE_MS )
|
||||
#define priLOOPS ( 5 )
|
||||
#define priMAX_COUNT ( ( unsigned portLONG ) 0xff )
|
||||
#define priNO_BLOCK ( ( portTickType ) 0 )
|
||||
#define priSUSPENDED_QUEUE_LENGTH ( 1 )
|
||||
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/* Handles to the two counter tasks. These could be passed in as parameters
|
||||
to the controller task to prevent them having to be file scope. */
|
||||
static xTaskHandle xContinousIncrementHandle, xLimitedIncrementHandle;
|
||||
|
||||
/* The shared counter variable. This is passed in as a parameter to the two
|
||||
counter variables for demonstration purposes. */
|
||||
static unsigned portLONG ulCounter;
|
||||
|
||||
/* Variables used to check that the tasks are still operating without error.
|
||||
Each complete iteration of the controller task increments this variable
|
||||
provided no errors have been found. The variable maintaining the same value
|
||||
is therefore indication of an error. */
|
||||
static volatile unsigned portSHORT usCheckVariable = ( unsigned portSHORT ) 0;
|
||||
static volatile portBASE_TYPE xSuspendedQueueSendError = pdFALSE;
|
||||
static volatile portBASE_TYPE xSuspendedQueueReceiveError = pdFALSE;
|
||||
|
||||
/* Queue used by the second test. */
|
||||
xQueueHandle xSuspendedTestQueue;
|
||||
|
||||
/*-----------------------------------------------------------*/
|
||||
/*
|
||||
* Start the three tasks as described at the top of the file.
|
||||
* Note that the limited count task is given a higher priority.
|
||||
*/
|
||||
void vStartDynamicPriorityTasks( void )
|
||||
{
|
||||
xSuspendedTestQueue = xQueueCreate( priSUSPENDED_QUEUE_LENGTH, sizeof( unsigned portLONG ) );
|
||||
xTaskCreate( vContinuousIncrementTask, ( signed portCHAR * ) "CNT_INC", priSTACK_SIZE, ( void * ) &ulCounter, tskIDLE_PRIORITY, &xContinousIncrementHandle );
|
||||
xTaskCreate( vLimitedIncrementTask, ( signed portCHAR * ) "LIM_INC", priSTACK_SIZE, ( void * ) &ulCounter, tskIDLE_PRIORITY + 1, &xLimitedIncrementHandle );
|
||||
xTaskCreate( vCounterControlTask, ( signed portCHAR * ) "C_CTRL", priSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
|
||||
xTaskCreate( vQueueSendWhenSuspendedTask, ( signed portCHAR * ) "SUSP_TX", priSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
|
||||
xTaskCreate( vQueueReceiveWhenSuspendedTask, ( signed portCHAR * ) "SUSP_RX", priSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Just loops around incrementing the shared variable until the limit has been
|
||||
* reached. Once the limit has been reached it suspends itself.
|
||||
*/
|
||||
static portTASK_FUNCTION( vLimitedIncrementTask, pvParameters )
|
||||
{
|
||||
unsigned portLONG *pulCounter;
|
||||
|
||||
/* Take a pointer to the shared variable from the parameters passed into
|
||||
the task. */
|
||||
pulCounter = ( unsigned portLONG * ) pvParameters;
|
||||
|
||||
/* This will run before the control task, so the first thing it does is
|
||||
suspend - the control task will resume it when ready. */
|
||||
vTaskSuspend( NULL );
|
||||
|
||||
for( ;; )
|
||||
{
|
||||
/* Just count up to a value then suspend. */
|
||||
( *pulCounter )++;
|
||||
|
||||
if( *pulCounter >= priMAX_COUNT )
|
||||
{
|
||||
vTaskSuspend( NULL );
|
||||
}
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Just keep counting the shared variable up. The control task will suspend
|
||||
* this task when it wants.
|
||||
*/
|
||||
static portTASK_FUNCTION( vContinuousIncrementTask, pvParameters )
|
||||
{
|
||||
unsigned portLONG *pulCounter;
|
||||
unsigned portBASE_TYPE uxOurPriority;
|
||||
|
||||
/* Take a pointer to the shared variable from the parameters passed into
|
||||
the task. */
|
||||
pulCounter = ( unsigned portLONG * ) pvParameters;
|
||||
|
||||
/* Query our priority so we can raise it when exclusive access to the
|
||||
shared variable is required. */
|
||||
uxOurPriority = uxTaskPriorityGet( NULL );
|
||||
|
||||
for( ;; )
|
||||
{
|
||||
/* Raise our priority above the controller task to ensure a context
|
||||
switch does not occur while we are accessing this variable. */
|
||||
vTaskPrioritySet( NULL, uxOurPriority + 1 );
|
||||
( *pulCounter )++;
|
||||
vTaskPrioritySet( NULL, uxOurPriority );
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Controller task as described above.
|
||||
*/
|
||||
static portTASK_FUNCTION( vCounterControlTask, pvParameters )
|
||||
{
|
||||
unsigned portLONG ulLastCounter;
|
||||
portSHORT sLoops;
|
||||
portSHORT sError = pdFALSE;
|
||||
|
||||
/* Just to stop warning messages. */
|
||||
( void ) pvParameters;
|
||||
|
||||
for( ;; )
|
||||
{
|
||||
/* Start with the counter at zero. */
|
||||
ulCounter = ( unsigned portLONG ) 0;
|
||||
|
||||
/* First section : */
|
||||
|
||||
/* Check the continuous count task is running. */
|
||||
for( sLoops = 0; sLoops < priLOOPS; sLoops++ )
|
||||
{
|
||||
/* Suspend the continuous count task so we can take a mirror of the
|
||||
shared variable without risk of corruption. */
|
||||
vTaskSuspend( xContinousIncrementHandle );
|
||||
ulLastCounter = ulCounter;
|
||||
vTaskResume( xContinousIncrementHandle );
|
||||
|
||||
/* Now delay to ensure the other task has processor time. */
|
||||
vTaskDelay( priSLEEP_TIME );
|
||||
|
||||
/* Check the shared variable again. This time to ensure mutual
|
||||
exclusion the whole scheduler will be locked. This is just for
|
||||
demo purposes! */
|
||||
vTaskSuspendAll();
|
||||
{
|
||||
if( ulLastCounter == ulCounter )
|
||||
{
|
||||
/* The shared variable has not changed. There is a problem
|
||||
with the continuous count task so flag an error. */
|
||||
sError = pdTRUE;
|
||||
}
|
||||
}
|
||||
xTaskResumeAll();
|
||||
}
|
||||
|
||||
|
||||
/* Second section: */
|
||||
|
||||
/* Suspend the continuous counter task so it stops accessing the shared variable. */
|
||||
vTaskSuspend( xContinousIncrementHandle );
|
||||
|
||||
/* Reset the variable. */
|
||||
ulCounter = ( unsigned portLONG ) 0;
|
||||
|
||||
/* Resume the limited count task which has a higher priority than us.
|
||||
We should therefore not return from this call until the limited count
|
||||
task has suspended itself with a known value in the counter variable. */
|
||||
vTaskResume( xLimitedIncrementHandle );
|
||||
|
||||
/* Does the counter variable have the expected value? */
|
||||
if( ulCounter != priMAX_COUNT )
|
||||
{
|
||||
sError = pdTRUE;
|
||||
}
|
||||
|
||||
if( sError == pdFALSE )
|
||||
{
|
||||
/* If no errors have occurred then increment the check variable. */
|
||||
portENTER_CRITICAL();
|
||||
usCheckVariable++;
|
||||
portEXIT_CRITICAL();
|
||||
}
|
||||
|
||||
/* Resume the continuous count task and do it all again. */
|
||||
vTaskResume( xContinousIncrementHandle );
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static portTASK_FUNCTION( vQueueSendWhenSuspendedTask, pvParameters )
|
||||
{
|
||||
static unsigned portLONG ulValueToSend = ( unsigned portLONG ) 0;
|
||||
|
||||
/* Just to stop warning messages. */
|
||||
( void ) pvParameters;
|
||||
|
||||
for( ;; )
|
||||
{
|
||||
vTaskSuspendAll();
|
||||
{
|
||||
/* We must not block while the scheduler is suspended! */
|
||||
if( xQueueSend( xSuspendedTestQueue, ( void * ) &ulValueToSend, priNO_BLOCK ) != pdTRUE )
|
||||
{
|
||||
xSuspendedQueueSendError = pdTRUE;
|
||||
}
|
||||
}
|
||||
xTaskResumeAll();
|
||||
|
||||
vTaskDelay( priSLEEP_TIME );
|
||||
|
||||
++ulValueToSend;
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static portTASK_FUNCTION( vQueueReceiveWhenSuspendedTask, pvParameters )
|
||||
{
|
||||
static unsigned portLONG ulExpectedValue = ( unsigned portLONG ) 0, ulReceivedValue;
|
||||
portBASE_TYPE xGotValue;
|
||||
|
||||
/* Just to stop warning messages. */
|
||||
( void ) pvParameters;
|
||||
|
||||
for( ;; )
|
||||
{
|
||||
do
|
||||
{
|
||||
/* Suspending the scheduler here is fairly pointless and
|
||||
undesirable for a normal application. It is done here purely
|
||||
to test the scheduler. The inner xTaskResumeAll() should
|
||||
never return pdTRUE as the scheduler is still locked by the
|
||||
outer call. */
|
||||
vTaskSuspendAll();
|
||||
{
|
||||
vTaskSuspendAll();
|
||||
{
|
||||
xGotValue = xQueueReceive( xSuspendedTestQueue, ( void * ) &ulReceivedValue, priNO_BLOCK );
|
||||
}
|
||||
if( xTaskResumeAll() )
|
||||
{
|
||||
xSuspendedQueueReceiveError = pdTRUE;
|
||||
}
|
||||
}
|
||||
xTaskResumeAll();
|
||||
|
||||
#if configUSE_PREEMPTION == 0
|
||||
{
|
||||
taskYIELD();
|
||||
}
|
||||
#endif
|
||||
|
||||
} while( xGotValue == pdFALSE );
|
||||
|
||||
if( ulReceivedValue != ulExpectedValue )
|
||||
{
|
||||
xSuspendedQueueReceiveError = pdTRUE;
|
||||
}
|
||||
|
||||
++ulExpectedValue;
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/* Called to check that all the created tasks are still running without error. */
|
||||
portBASE_TYPE xAreDynamicPriorityTasksStillRunning( void )
|
||||
{
|
||||
/* Keep a history of the check variables so we know if it has been incremented
|
||||
since the last call. */
|
||||
static unsigned portSHORT usLastTaskCheck = ( unsigned portSHORT ) 0;
|
||||
portBASE_TYPE xReturn = pdTRUE;
|
||||
|
||||
/* Check the tasks are still running by ensuring the check variable
|
||||
is still incrementing. */
|
||||
|
||||
if( usCheckVariable == usLastTaskCheck )
|
||||
{
|
||||
/* The check has not incremented so an error exists. */
|
||||
xReturn = pdFALSE;
|
||||
}
|
||||
|
||||
if( xSuspendedQueueSendError == pdTRUE )
|
||||
{
|
||||
xReturn = pdFALSE;
|
||||
}
|
||||
|
||||
if( xSuspendedQueueReceiveError == pdTRUE )
|
||||
{
|
||||
xReturn = pdFALSE;
|
||||
}
|
||||
|
||||
usLastTaskCheck = usCheckVariable;
|
||||
return xReturn;
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue