/* FreeRTOS V8.2.0rc1 - Copyright (C) 2014 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 1 tab == 4 spaces! *************************************************************************** * * * Having a problem? Start by reading the FAQ "My application does * * not run, what could be wrong?". Have you defined configASSERT()? * * * * http://www.FreeRTOS.org/FAQHelp.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 * * * *************************************************************************** *************************************************************************** * * * Investing in training allows your team to be as productive as * * possible as early as possible, lowering your overall development * * cost, and enabling you to bring a more robust product to market * * earlier than would otherwise be possible. Richard Barry is both * * the architect and key author of FreeRTOS, and so also the world's * * leading authority on what is the world's most popular real time * * kernel for deeply embedded MCU designs. Obtaining your training * * from Richard ensures your team will gain directly from his in-depth * * product knowledge and years of usage experience. Contact Real Time * * Engineers Ltd to enquire about the FreeRTOS Masterclass, presented * * by Richard Barry: http://www.FreeRTOS.org/contact * * *************************************************************************** *************************************************************************** * * * You are receiving this top quality software for free. Please play * * fair and reciprocate by reporting any suspected issues and * * participating in the community forum: * * http://www.FreeRTOS.org/support * * * * Thank you! * * * *************************************************************************** http://www.FreeRTOS.org - Documentation, books, training, latest versions, license and Real Time Engineers Ltd. contact details. 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! */ /** * Create a single persistent task which periodically dynamically creates another * four tasks. The original task is called the creator task, the four tasks it * creates are called suicidal tasks. * * Two of the created suicidal tasks kill one other suicidal task before killing * themselves - leaving just the original task remaining. * * The creator task must be spawned after all of the other demo application tasks * as it keeps a check on the number of tasks under the scheduler control. The * number of tasks it expects to see running should never be greater than the * number of tasks that were in existence when the creator task was spawned, plus * one set of four suicidal tasks. If this number is exceeded an error is flagged. * * \page DeathC death.c * \ingroup DemoFiles *
*/ /* Changes from V2.0.0 + Delay periods are now specified using variables and constants of TickType_t rather than unsigned long. */ #include /* Scheduler include files. */ #include "FreeRTOS.h" #include "task.h" /* Demo program include files. */ #include "death.h" #include "print.h" #define deathSTACK_SIZE ( ( unsigned short ) 512 ) /* The task originally created which is responsible for periodically dynamically creating another four tasks. */ static void vCreateTasks( void *pvParameters ); /* The task function of the dynamically created tasks. */ static void vSuicidalTask( void *pvParameters ); /* A variable which is incremented every time the dynamic tasks are created. This is used to check that the task is still running. */ static volatile short sCreationCount = 0; /* Used to store the number of tasks that were originally running so the creator task can tell if any of the suicidal tasks have failed to die. */ static volatile unsigned portBASE_TYPE uxTasksRunningAtStart = 0; static const unsigned portBASE_TYPE uxMaxNumberOfExtraTasksRunning = 5; /* Used to store a handle to the tasks that should be killed by a suicidal task, before it kills itself. */ TaskHandle_t xCreatedTask1, xCreatedTask2; /*-----------------------------------------------------------*/ void vCreateSuicidalTasks( unsigned portBASE_TYPE uxPriority ) { unsigned portBASE_TYPE *puxPriority; /* Create the Creator tasks - passing in as a parameter the priority at which the suicidal tasks should be created. */ puxPriority = ( unsigned portBASE_TYPE * ) pvPortMalloc( sizeof( unsigned portBASE_TYPE ) ); *puxPriority = uxPriority; xTaskCreate( vCreateTasks, "CREATOR", deathSTACK_SIZE, ( void * ) puxPriority, uxPriority, NULL ); /* Record the number of tasks that are running now so we know if any of the suicidal tasks have failed to be killed. */ uxTasksRunningAtStart = uxTaskGetNumberOfTasks(); } /*-----------------------------------------------------------*/ static void vSuicidalTask( void *pvParameters ) { portDOUBLE d1, d2; TaskHandle_t xTaskToKill; const TickType_t xDelay = ( TickType_t ) 500 / portTICK_PERIOD_MS; if( pvParameters != NULL ) { /* This task is periodically created four times. Tow created tasks are passed a handle to the other task so it can kill it before killing itself. The other task is passed in null. */ xTaskToKill = *( TaskHandle_t* )pvParameters; } else { xTaskToKill = NULL; } for( ;; ) { /* Do something random just to use some stack and registers. */ d1 = 2.4; d2 = 89.2; d2 *= d1; vTaskDelay( xDelay ); if( xTaskToKill != NULL ) { /* Make sure the other task has a go before we delete it. */ vTaskDelay( ( TickType_t ) 0 ); /* Kill the other task that was created by vCreateTasks(). */ vTaskDelete( xTaskToKill ); /* Kill ourselves. */ vTaskDelete( NULL ); } } }/*lint !e818 !e550 Function prototype must be as per standard for task functions. */ /*-----------------------------------------------------------*/ static void vCreateTasks( void *pvParameters ) { const TickType_t xDelay = ( TickType_t ) 1000 / portTICK_PERIOD_MS; unsigned portBASE_TYPE uxPriority; const char * const pcTaskStartMsg = "Create task started.\r\n"; /* Queue a message for printing to say the task has started. */ vPrintDisplayMessage( &pcTaskStartMsg ); uxPriority = *( unsigned portBASE_TYPE * ) pvParameters; vPortFree( pvParameters ); for( ;; ) { /* Just loop round, delaying then creating the four suicidal tasks. */ vTaskDelay( xDelay ); xTaskCreate( vSuicidalTask, "SUICIDE1", deathSTACK_SIZE, NULL, uxPriority, &xCreatedTask1 ); xTaskCreate( vSuicidalTask, "SUICIDE2", deathSTACK_SIZE, &xCreatedTask1, uxPriority, NULL ); xTaskCreate( vSuicidalTask, "SUICIDE1", deathSTACK_SIZE, NULL, uxPriority, &xCreatedTask2 ); xTaskCreate( vSuicidalTask, "SUICIDE2", deathSTACK_SIZE, &xCreatedTask2, uxPriority, NULL ); ++sCreationCount; } } /*-----------------------------------------------------------*/ /* This is called to check that the creator task is still running and that there are not any more than four extra tasks. */ portBASE_TYPE xIsCreateTaskStillRunning( void ) { static short sLastCreationCount = 0; short sReturn = pdTRUE; unsigned portBASE_TYPE uxTasksRunningNow; if( sLastCreationCount == sCreationCount ) { sReturn = pdFALSE; } uxTasksRunningNow = uxTaskGetNumberOfTasks(); if( uxTasksRunningNow < uxTasksRunningAtStart ) { sReturn = pdFALSE; } else if( ( uxTasksRunningNow - uxTasksRunningAtStart ) > uxMaxNumberOfExtraTasksRunning ) { sReturn = pdFALSE; } else { /* Everything is okay. */ } return sReturn; }