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Diffstat (limited to 'src/FreeRTOS-Sim-master/Demo/Common/Minimal/recmutex.c')
| -rw-r--r-- | src/FreeRTOS-Sim-master/Demo/Common/Minimal/recmutex.c | 444 |
1 files changed, 444 insertions, 0 deletions
diff --git a/src/FreeRTOS-Sim-master/Demo/Common/Minimal/recmutex.c b/src/FreeRTOS-Sim-master/Demo/Common/Minimal/recmutex.c new file mode 100644 index 0000000..f59d360 --- /dev/null +++ b/src/FreeRTOS-Sim-master/Demo/Common/Minimal/recmutex.c @@ -0,0 +1,444 @@ +/*
+ FreeRTOS V8.2.2 - Copyright (C) 2015 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!
+*/
+
+/*
+ The tasks defined on this page demonstrate the use of recursive mutexes.
+
+ For recursive mutex functionality the created mutex should be created using
+ xSemaphoreCreateRecursiveMutex(), then be manipulated
+ using the xSemaphoreTakeRecursive() and xSemaphoreGiveRecursive() API
+ functions.
+
+ This demo creates three tasks all of which access the same recursive mutex:
+
+ prvRecursiveMutexControllingTask() has the highest priority so executes
+ first and grabs the mutex. It then performs some recursive accesses -
+ between each of which it sleeps for a short period to let the lower
+ priority tasks execute. When it has completed its demo functionality
+ it gives the mutex back before suspending itself.
+
+ prvRecursiveMutexBlockingTask() attempts to access the mutex by performing
+ a blocking 'take'. The blocking task has a lower priority than the
+ controlling task so by the time it executes the mutex has already been
+ taken by the controlling task, causing the blocking task to block. It
+ does not unblock until the controlling task has given the mutex back,
+ and it does not actually run until the controlling task has suspended
+ itself (due to the relative priorities). When it eventually does obtain
+ the mutex all it does is give the mutex back prior to also suspending
+ itself. At this point both the controlling task and the blocking task are
+ suspended.
+
+ prvRecursiveMutexPollingTask() runs at the idle priority. It spins round
+ a tight loop attempting to obtain the mutex with a non-blocking call. As
+ the lowest priority task it will not successfully obtain the mutex until
+ both the controlling and blocking tasks are suspended. Once it eventually
+ does obtain the mutex it first unsuspends both the controlling task and
+ blocking task prior to giving the mutex back - resulting in the polling
+ task temporarily inheriting the controlling tasks priority.
+*/
+
+/* Scheduler include files. */
+#include "FreeRTOS.h"
+#include "task.h"
+#include "semphr.h"
+
+/* Demo app include files. */
+#include "recmutex.h"
+
+/* Priorities assigned to the three tasks. recmuCONTROLLING_TASK_PRIORITY can
+be overridden by a definition in FreeRTOSConfig.h. */
+#ifndef recmuCONTROLLING_TASK_PRIORITY
+ #define recmuCONTROLLING_TASK_PRIORITY ( tskIDLE_PRIORITY + 2 )
+#endif
+#define recmuBLOCKING_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )
+#define recmuPOLLING_TASK_PRIORITY ( tskIDLE_PRIORITY + 0 )
+
+/* The recursive call depth. */
+#define recmuMAX_COUNT ( 10 )
+
+/* Misc. */
+#define recmuSHORT_DELAY ( 20 / portTICK_PERIOD_MS )
+#define recmuNO_DELAY ( ( TickType_t ) 0 )
+#define recmuEIGHT_TICK_DELAY ( ( TickType_t ) 8 )
+
+/* The three tasks as described at the top of this file. */
+static void prvRecursiveMutexControllingTask( void *pvParameters );
+static void prvRecursiveMutexBlockingTask( void *pvParameters );
+static void prvRecursiveMutexPollingTask( void *pvParameters );
+
+/* The mutex used by the demo. */
+static SemaphoreHandle_t xMutex;
+
+/* Variables used to detect and latch errors. */
+static volatile BaseType_t xErrorOccurred = pdFALSE, xControllingIsSuspended = pdFALSE, xBlockingIsSuspended = pdFALSE;
+static volatile UBaseType_t uxControllingCycles = 0, uxBlockingCycles = 0, uxPollingCycles = 0;
+
+/* Handles of the two higher priority tasks, required so they can be resumed
+(unsuspended). */
+static TaskHandle_t xControllingTaskHandle, xBlockingTaskHandle;
+
+/*-----------------------------------------------------------*/
+
+void vStartRecursiveMutexTasks( void )
+{
+ /* Just creates the mutex and the three tasks. */
+
+ xMutex = xSemaphoreCreateRecursiveMutex();
+
+ /* vQueueAddToRegistry() adds the mutex to the registry, if one is
+ in use. The registry is provided as a means for kernel aware
+ debuggers to locate mutex and has no purpose if a kernel aware debugger
+ is not being used. The call to vQueueAddToRegistry() will be removed
+ by the pre-processor if configQUEUE_REGISTRY_SIZE is not defined or is
+ defined to be less than 1. */
+ vQueueAddToRegistry( ( QueueHandle_t ) xMutex, "Recursive_Mutex" );
+
+
+ if( xMutex != NULL )
+ {
+ xTaskCreate( prvRecursiveMutexControllingTask, "Rec1", configMINIMAL_STACK_SIZE, NULL, recmuCONTROLLING_TASK_PRIORITY, &xControllingTaskHandle );
+ xTaskCreate( prvRecursiveMutexBlockingTask, "Rec2", configMINIMAL_STACK_SIZE, NULL, recmuBLOCKING_TASK_PRIORITY, &xBlockingTaskHandle );
+ xTaskCreate( prvRecursiveMutexPollingTask, "Rec3", configMINIMAL_STACK_SIZE, NULL, recmuPOLLING_TASK_PRIORITY, NULL );
+ }
+}
+/*-----------------------------------------------------------*/
+
+static void prvRecursiveMutexControllingTask( void *pvParameters )
+{
+UBaseType_t ux;
+
+ /* Just to remove compiler warning. */
+ ( void ) pvParameters;
+
+ for( ;; )
+ {
+ /* Should not be able to 'give' the mutex, as we have not yet 'taken'
+ it. The first time through, the mutex will not have been used yet,
+ subsequent times through, at this point the mutex will be held by the
+ polling task. */
+ if( xSemaphoreGiveRecursive( xMutex ) == pdPASS )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ for( ux = 0; ux < recmuMAX_COUNT; ux++ )
+ {
+ /* We should now be able to take the mutex as many times as
+ we like.
+
+ The first time through the mutex will be immediately available, on
+ subsequent times through the mutex will be held by the polling task
+ at this point and this Take will cause the polling task to inherit
+ the priority of this task. In this case the block time must be
+ long enough to ensure the polling task will execute again before the
+ block time expires. If the block time does expire then the error
+ flag will be set here. */
+ if( xSemaphoreTakeRecursive( xMutex, recmuEIGHT_TICK_DELAY ) != pdPASS )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ /* Ensure the other task attempting to access the mutex (and the
+ other demo tasks) are able to execute to ensure they either block
+ (where a block time is specified) or return an error (where no
+ block time is specified) as the mutex is held by this task. */
+ vTaskDelay( recmuSHORT_DELAY );
+ }
+
+ /* For each time we took the mutex, give it back. */
+ for( ux = 0; ux < recmuMAX_COUNT; ux++ )
+ {
+ /* Ensure the other task attempting to access the mutex (and the
+ other demo tasks) are able to execute. */
+ vTaskDelay( recmuSHORT_DELAY );
+
+ /* We should now be able to give the mutex as many times as we
+ took it. When the mutex is available again the Blocking task
+ should be unblocked but not run because it has a lower priority
+ than this task. The polling task should also not run at this point
+ as it too has a lower priority than this task. */
+ if( xSemaphoreGiveRecursive( xMutex ) != pdPASS )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+ }
+
+ /* Having given it back the same number of times as it was taken, we
+ should no longer be the mutex owner, so the next give should fail. */
+ if( xSemaphoreGiveRecursive( xMutex ) == pdPASS )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ /* Keep count of the number of cycles this task has performed so a
+ stall can be detected. */
+ uxControllingCycles++;
+
+ /* Suspend ourselves so the blocking task can execute. */
+ xControllingIsSuspended = pdTRUE;
+ vTaskSuspend( NULL );
+ xControllingIsSuspended = pdFALSE;
+ }
+}
+/*-----------------------------------------------------------*/
+
+static void prvRecursiveMutexBlockingTask( void *pvParameters )
+{
+ /* Just to remove compiler warning. */
+ ( void ) pvParameters;
+
+ for( ;; )
+ {
+ /* This task will run while the controlling task is blocked, and the
+ controlling task will block only once it has the mutex - therefore
+ this call should block until the controlling task has given up the
+ mutex, and not actually execute past this call until the controlling
+ task is suspended. portMAX_DELAY - 1 is used instead of portMAX_DELAY
+ to ensure the task's state is reported as Blocked and not Suspended in
+ a later call to configASSERT() (within the polling task). */
+ if( xSemaphoreTakeRecursive( xMutex, ( portMAX_DELAY - 1 ) ) == pdPASS )
+ {
+ if( xControllingIsSuspended != pdTRUE )
+ {
+ /* Did not expect to execute until the controlling task was
+ suspended. */
+ xErrorOccurred = pdTRUE;
+ }
+ else
+ {
+ /* Give the mutex back before suspending ourselves to allow
+ the polling task to obtain the mutex. */
+ if( xSemaphoreGiveRecursive( xMutex ) != pdPASS )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ xBlockingIsSuspended = pdTRUE;
+ vTaskSuspend( NULL );
+ xBlockingIsSuspended = pdFALSE;
+ }
+ }
+ else
+ {
+ /* We should not leave the xSemaphoreTakeRecursive() function
+ until the mutex was obtained. */
+ xErrorOccurred = pdTRUE;
+ }
+
+ /* The controlling and blocking tasks should be in lock step. */
+ if( uxControllingCycles != ( uxBlockingCycles + 1 ) )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ /* Keep count of the number of cycles this task has performed so a
+ stall can be detected. */
+ uxBlockingCycles++;
+ }
+}
+/*-----------------------------------------------------------*/
+
+static void prvRecursiveMutexPollingTask( void *pvParameters )
+{
+ /* Just to remove compiler warning. */
+ ( void ) pvParameters;
+
+ for( ;; )
+ {
+ /* Keep attempting to obtain the mutex. We should only obtain it when
+ the blocking task has suspended itself, which in turn should only
+ happen when the controlling task is also suspended. */
+ if( xSemaphoreTakeRecursive( xMutex, recmuNO_DELAY ) == pdPASS )
+ {
+ #if( INCLUDE_eTaskGetState == 1 )
+ {
+ configASSERT( eTaskGetState( xControllingTaskHandle ) == eSuspended );
+ configASSERT( eTaskGetState( xBlockingTaskHandle ) == eSuspended );
+ }
+ #endif /* INCLUDE_eTaskGetState */
+
+ /* Is the blocking task suspended? */
+ if( ( xBlockingIsSuspended != pdTRUE ) || ( xControllingIsSuspended != pdTRUE ) )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+ else
+ {
+ /* Keep count of the number of cycles this task has performed
+ so a stall can be detected. */
+ uxPollingCycles++;
+
+ /* We can resume the other tasks here even though they have a
+ higher priority than the polling task. When they execute they
+ will attempt to obtain the mutex but fail because the polling
+ task is still the mutex holder. The polling task (this task)
+ will then inherit the higher priority. The Blocking task will
+ block indefinitely when it attempts to obtain the mutex, the
+ Controlling task will only block for a fixed period and an
+ error will be latched if the polling task has not returned the
+ mutex by the time this fixed period has expired. */
+ vTaskResume( xBlockingTaskHandle );
+ vTaskResume( xControllingTaskHandle );
+
+ /* The other two tasks should now have executed and no longer
+ be suspended. */
+ if( ( xBlockingIsSuspended == pdTRUE ) || ( xControllingIsSuspended == pdTRUE ) )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ #if( INCLUDE_uxTaskPriorityGet == 1 )
+ {
+ /* Check priority inherited. */
+ configASSERT( uxTaskPriorityGet( NULL ) == recmuCONTROLLING_TASK_PRIORITY );
+ }
+ #endif /* INCLUDE_uxTaskPriorityGet */
+
+ #if( INCLUDE_eTaskGetState == 1 )
+ {
+ configASSERT( eTaskGetState( xControllingTaskHandle ) == eBlocked );
+ configASSERT( eTaskGetState( xBlockingTaskHandle ) == eBlocked );
+ }
+ #endif /* INCLUDE_eTaskGetState */
+
+ /* Release the mutex, disinheriting the higher priority again. */
+ if( xSemaphoreGiveRecursive( xMutex ) != pdPASS )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+
+ #if( INCLUDE_uxTaskPriorityGet == 1 )
+ {
+ /* Check priority disinherited. */
+ configASSERT( uxTaskPriorityGet( NULL ) == recmuPOLLING_TASK_PRIORITY );
+ }
+ #endif /* INCLUDE_uxTaskPriorityGet */
+ }
+ }
+
+ #if configUSE_PREEMPTION == 0
+ {
+ taskYIELD();
+ }
+ #endif
+ }
+}
+/*-----------------------------------------------------------*/
+
+/* This is called to check that all the created tasks are still running. */
+BaseType_t xAreRecursiveMutexTasksStillRunning( void )
+{
+BaseType_t xReturn;
+static UBaseType_t uxLastControllingCycles = 0, uxLastBlockingCycles = 0, uxLastPollingCycles = 0;
+
+ /* Is the controlling task still cycling? */
+ if( uxLastControllingCycles == uxControllingCycles )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+ else
+ {
+ uxLastControllingCycles = uxControllingCycles;
+ }
+
+ /* Is the blocking task still cycling? */
+ if( uxLastBlockingCycles == uxBlockingCycles )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+ else
+ {
+ uxLastBlockingCycles = uxBlockingCycles;
+ }
+
+ /* Is the polling task still cycling? */
+ if( uxLastPollingCycles == uxPollingCycles )
+ {
+ xErrorOccurred = pdTRUE;
+ }
+ else
+ {
+ uxLastPollingCycles = uxPollingCycles;
+ }
+
+ if( xErrorOccurred == pdTRUE )
+ {
+ xReturn = pdFAIL;
+ }
+ else
+ {
+ xReturn = pdTRUE;
+ }
+
+ return xReturn;
+}
+
+
+
+
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