369 lines
15 KiB
C
369 lines
15 KiB
C
|
/*
|
||
|
|
* FreeRTOS Kernel V10.2.1
|
||
|
|
* Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
|
||
|
|
*
|
||
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy of
|
||
|
|
* this software and associated documentation files (the "Software"), to deal in
|
||
|
|
* the Software without restriction, including without limitation the rights to
|
||
|
|
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
|
||
|
|
* the Software, and to permit persons to whom the Software is furnished to do so,
|
||
|
|
* subject to the following conditions:
|
||
|
|
*
|
||
|
|
* The above copyright notice and this permission notice shall be included in all
|
||
|
|
* copies or substantial portions of the Software.
|
||
|
|
*
|
||
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
|
||
|
|
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
|
||
|
|
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
|
||
|
|
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
|
||
|
|
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
||
|
|
*
|
||
|
|
* http://www.FreeRTOS.org
|
||
|
|
* http://aws.amazon.com/freertos
|
||
|
|
*
|
||
|
|
* 1 tab == 4 spaces!
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* This file exercises the event mechanism whereby more than one task is
|
||
|
|
* blocked waiting for the same event.
|
||
|
|
*
|
||
|
|
* The demo creates five tasks - four 'event' tasks, and a controlling task.
|
||
|
|
* The event tasks have various different priorities and all block on reading
|
||
|
|
* the same queue. The controlling task writes data to the queue, then checks
|
||
|
|
* to see which of the event tasks read the data from the queue. The
|
||
|
|
* controlling task has the lowest priority of all the tasks so is guaranteed
|
||
|
|
* to always get preempted immediately upon writing to the queue.
|
||
|
|
*
|
||
|
|
* By selectively suspending and resuming the event tasks the controlling task
|
||
|
|
* can check that the highest priority task that is blocked on the queue is the
|
||
|
|
* task that reads the posted data from the queue.
|
||
|
|
*
|
||
|
|
* Two of the event tasks share the same priority. When neither of these tasks
|
||
|
|
* are suspended they should alternate - one reading one message from the queue,
|
||
|
|
* the other the next message, etc.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* Standard includes. */
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <string.h>
|
||
|
|
|
||
|
|
/* Scheduler include files. */
|
||
|
|
#include "FreeRTOS.h"
|
||
|
|
#include "task.h"
|
||
|
|
#include "queue.h"
|
||
|
|
|
||
|
|
/* Demo program include files. */
|
||
|
|
#include "mevents.h"
|
||
|
|
#include "print.h"
|
||
|
|
|
||
|
|
/* Demo specific constants. */
|
||
|
|
#define evtSTACK_SIZE ( ( unsigned portBASE_TYPE ) configMINIMAL_STACK_SIZE )
|
||
|
|
#define evtNUM_TASKS ( 4 )
|
||
|
|
#define evtQUEUE_LENGTH ( ( unsigned portBASE_TYPE ) 3 )
|
||
|
|
#define evtNO_DELAY 0
|
||
|
|
|
||
|
|
/* Just indexes used to uniquely identify the tasks. Note that two tasks are
|
||
|
|
'highest' priority. */
|
||
|
|
#define evtHIGHEST_PRIORITY_INDEX_2 3
|
||
|
|
#define evtHIGHEST_PRIORITY_INDEX_1 2
|
||
|
|
#define evtMEDIUM_PRIORITY_INDEX 1
|
||
|
|
#define evtLOWEST_PRIORITY_INDEX 0
|
||
|
|
|
||
|
|
/* Each event task increments one of these counters each time it reads data
|
||
|
|
from the queue. */
|
||
|
|
static volatile portBASE_TYPE xTaskCounters[ evtNUM_TASKS ] = { 0, 0, 0, 0 };
|
||
|
|
|
||
|
|
/* Each time the controlling task posts onto the queue it increments the
|
||
|
|
expected count of the task that it expected to read the data from the queue
|
||
|
|
(i.e. the task with the highest priority that should be blocked on the queue).
|
||
|
|
|
||
|
|
xExpectedTaskCounters are incremented from the controlling task, and
|
||
|
|
xTaskCounters are incremented from the individual event tasks - therefore
|
||
|
|
comparing xTaskCounters to xExpectedTaskCounters shows whether or not the
|
||
|
|
correct task was unblocked by the post. */
|
||
|
|
static portBASE_TYPE xExpectedTaskCounters[ evtNUM_TASKS ] = { 0, 0, 0, 0 };
|
||
|
|
|
||
|
|
/* Handles to the four event tasks. These are required to suspend and resume
|
||
|
|
the tasks. */
|
||
|
|
static TaskHandle_t xCreatedTasks[ evtNUM_TASKS ];
|
||
|
|
|
||
|
|
/* The single queue onto which the controlling task posts, and the four event
|
||
|
|
tasks block. */
|
||
|
|
static QueueHandle_t xQueue;
|
||
|
|
|
||
|
|
/* Flag used to indicate whether or not an error has occurred at any time.
|
||
|
|
An error is either the queue being full when not expected, or an unexpected
|
||
|
|
task reading data from the queue. */
|
||
|
|
static portBASE_TYPE xHealthStatus = pdPASS;
|
||
|
|
|
||
|
|
/*-----------------------------------------------------------*/
|
||
|
|
|
||
|
|
/* Function that implements the event task. This is created four times. */
|
||
|
|
static void prvMultiEventTask( void *pvParameters );
|
||
|
|
|
||
|
|
/* Function that implements the controlling task. */
|
||
|
|
static void prvEventControllerTask( void *pvParameters );
|
||
|
|
|
||
|
|
/* This is a utility function that posts data to the queue, then compares
|
||
|
|
xExpectedTaskCounters with xTaskCounters to ensure everything worked as
|
||
|
|
expected.
|
||
|
|
|
||
|
|
The event tasks all have higher priorities the controlling task. Therefore
|
||
|
|
the controlling task will always get preempted between writhing to the queue
|
||
|
|
and checking the task counters.
|
||
|
|
|
||
|
|
@param xExpectedTask The index to the task that the controlling task thinks
|
||
|
|
should be the highest priority task waiting for data, and
|
||
|
|
therefore the task that will unblock.
|
||
|
|
|
||
|
|
@param xIncrement The number of items that should be written to the queue.
|
||
|
|
*/
|
||
|
|
static void prvCheckTaskCounters( portBASE_TYPE xExpectedTask, portBASE_TYPE xIncrement );
|
||
|
|
|
||
|
|
/* This is just incremented each cycle of the controlling tasks function so
|
||
|
|
the main application can ensure the test is still running. */
|
||
|
|
static portBASE_TYPE xCheckVariable = 0;
|
||
|
|
|
||
|
|
/*-----------------------------------------------------------*/
|
||
|
|
|
||
|
|
void vStartMultiEventTasks( void )
|
||
|
|
{
|
||
|
|
/* Create the queue to be used for all the communications. */
|
||
|
|
xQueue = xQueueCreate( evtQUEUE_LENGTH, ( unsigned portBASE_TYPE ) sizeof( unsigned portBASE_TYPE ) );
|
||
|
|
|
||
|
|
/* Start the controlling task. This has the idle priority to ensure it is
|
||
|
|
always preempted by the event tasks. */
|
||
|
|
xTaskCreate( prvEventControllerTask, "EvntCTRL", evtSTACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
|
||
|
|
|
||
|
|
/* Start the four event tasks. Note that two have priority 3, one
|
||
|
|
priority 2 and the other priority 1. */
|
||
|
|
xTaskCreate( prvMultiEventTask, "Event0", evtSTACK_SIZE, ( void * ) &( xTaskCounters[ 0 ] ), 1, &( xCreatedTasks[ evtLOWEST_PRIORITY_INDEX ] ) );
|
||
|
|
xTaskCreate( prvMultiEventTask, "Event1", evtSTACK_SIZE, ( void * ) &( xTaskCounters[ 1 ] ), 2, &( xCreatedTasks[ evtMEDIUM_PRIORITY_INDEX ] ) );
|
||
|
|
xTaskCreate( prvMultiEventTask, "Event2", evtSTACK_SIZE, ( void * ) &( xTaskCounters[ 2 ] ), 3, &( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] ) );
|
||
|
|
xTaskCreate( prvMultiEventTask, "Event3", evtSTACK_SIZE, ( void * ) &( xTaskCounters[ 3 ] ), 3, &( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_2 ] ) );
|
||
|
|
}
|
||
|
|
/*-----------------------------------------------------------*/
|
||
|
|
|
||
|
|
static void prvMultiEventTask( void *pvParameters )
|
||
|
|
{
|
||
|
|
portBASE_TYPE *pxCounter;
|
||
|
|
unsigned portBASE_TYPE uxDummy;
|
||
|
|
const char * const pcTaskStartMsg = "Multi event task started.\r\n";
|
||
|
|
|
||
|
|
/* The variable this task will increment is passed in as a parameter. */
|
||
|
|
pxCounter = ( portBASE_TYPE * ) pvParameters;
|
||
|
|
|
||
|
|
vPrintDisplayMessage( &pcTaskStartMsg );
|
||
|
|
|
||
|
|
for( ;; )
|
||
|
|
{
|
||
|
|
/* Block on the queue. */
|
||
|
|
if( xQueueReceive( xQueue, &uxDummy, portMAX_DELAY ) )
|
||
|
|
{
|
||
|
|
/* We unblocked by reading the queue - so simply increment
|
||
|
|
the counter specific to this task instance. */
|
||
|
|
( *pxCounter )++;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
/*-----------------------------------------------------------*/
|
||
|
|
|
||
|
|
static void prvEventControllerTask( void *pvParameters )
|
||
|
|
{
|
||
|
|
const char * const pcTaskStartMsg = "Multi event controller task started.\r\n";
|
||
|
|
portBASE_TYPE xDummy = 0;
|
||
|
|
|
||
|
|
/* Just to stop warnings. */
|
||
|
|
( void ) pvParameters;
|
||
|
|
|
||
|
|
vPrintDisplayMessage( &pcTaskStartMsg );
|
||
|
|
|
||
|
|
for( ;; )
|
||
|
|
{
|
||
|
|
/* All tasks are blocked on the queue. When a message is posted one of
|
||
|
|
the two tasks that share the highest priority should unblock to read
|
||
|
|
the queue. The next message written should unblock the other task with
|
||
|
|
the same high priority, and so on in order. No other task should
|
||
|
|
unblock to read data as they have lower priorities. */
|
||
|
|
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_1, 1 );
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_2, 1 );
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_1, 1 );
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_2, 1 );
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_1, 1 );
|
||
|
|
|
||
|
|
/* For the rest of these tests we don't need the second 'highest'
|
||
|
|
priority task - so it is suspended. */
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_2 ] );
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/* Now suspend the other highest priority task. The medium priority
|
||
|
|
task will then be the task with the highest priority that remains
|
||
|
|
blocked on the queue. */
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
|
||
|
|
/* This time, when we post onto the queue we will expect the medium
|
||
|
|
priority task to unblock and preempt us. */
|
||
|
|
prvCheckTaskCounters( evtMEDIUM_PRIORITY_INDEX, 1 );
|
||
|
|
|
||
|
|
/* Now try resuming the highest priority task while the scheduler is
|
||
|
|
suspended. The task should start executing as soon as the scheduler
|
||
|
|
is resumed - therefore when we post to the queue again, the highest
|
||
|
|
priority task should again preempt us. */
|
||
|
|
vTaskSuspendAll();
|
||
|
|
vTaskResume( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
xTaskResumeAll();
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_1, 1 );
|
||
|
|
|
||
|
|
/* Now we are going to suspend the high and medium priority tasks. The
|
||
|
|
low priority task should then preempt us. Again the task suspension is
|
||
|
|
done with the whole scheduler suspended just for test purposes. */
|
||
|
|
vTaskSuspendAll();
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtMEDIUM_PRIORITY_INDEX ] );
|
||
|
|
xTaskResumeAll();
|
||
|
|
prvCheckTaskCounters( evtLOWEST_PRIORITY_INDEX, 1 );
|
||
|
|
|
||
|
|
/* Do the same basic test another few times - selectively suspending
|
||
|
|
and resuming tasks and each time calling prvCheckTaskCounters() passing
|
||
|
|
to the function the number of the task we expected to be unblocked by
|
||
|
|
the post. */
|
||
|
|
|
||
|
|
vTaskResume( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_1, 1 );
|
||
|
|
|
||
|
|
vTaskSuspendAll(); /* Just for test. */
|
||
|
|
vTaskSuspendAll(); /* Just for test. */
|
||
|
|
vTaskSuspendAll(); /* Just for even more test. */
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
xTaskResumeAll();
|
||
|
|
xTaskResumeAll();
|
||
|
|
xTaskResumeAll();
|
||
|
|
prvCheckTaskCounters( evtLOWEST_PRIORITY_INDEX, 1 );
|
||
|
|
|
||
|
|
vTaskResume( xCreatedTasks[ evtMEDIUM_PRIORITY_INDEX ] );
|
||
|
|
prvCheckTaskCounters( evtMEDIUM_PRIORITY_INDEX, 1 );
|
||
|
|
|
||
|
|
vTaskResume( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
prvCheckTaskCounters( evtHIGHEST_PRIORITY_INDEX_1, 1 );
|
||
|
|
|
||
|
|
/* Now a slight change, first suspend all tasks. */
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtMEDIUM_PRIORITY_INDEX ] );
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtLOWEST_PRIORITY_INDEX ] );
|
||
|
|
|
||
|
|
/* Now when we resume the low priority task and write to the queue 3
|
||
|
|
times. We expect the low priority task to service the queue three
|
||
|
|
times. */
|
||
|
|
vTaskResume( xCreatedTasks[ evtLOWEST_PRIORITY_INDEX ] );
|
||
|
|
prvCheckTaskCounters( evtLOWEST_PRIORITY_INDEX, evtQUEUE_LENGTH );
|
||
|
|
|
||
|
|
/* Again suspend all tasks (only the low priority task is not suspended
|
||
|
|
already). */
|
||
|
|
vTaskSuspend( xCreatedTasks[ evtLOWEST_PRIORITY_INDEX ] );
|
||
|
|
|
||
|
|
/* This time we are going to suspend the scheduler, resume the low
|
||
|
|
priority task, then resume the high priority task. In this state we
|
||
|
|
will write to the queue three times. When the scheduler is resumed
|
||
|
|
we expect the high priority task to service all three messages. */
|
||
|
|
vTaskSuspendAll();
|
||
|
|
{
|
||
|
|
vTaskResume( xCreatedTasks[ evtLOWEST_PRIORITY_INDEX ] );
|
||
|
|
vTaskResume( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_1 ] );
|
||
|
|
|
||
|
|
for( xDummy = 0; xDummy < evtQUEUE_LENGTH; xDummy++ )
|
||
|
|
{
|
||
|
|
if( xQueueSend( xQueue, &xDummy, evtNO_DELAY ) != pdTRUE )
|
||
|
|
{
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* The queue should not have been serviced yet!. The scheduler
|
||
|
|
is still suspended. */
|
||
|
|
if( memcmp( ( void * ) xExpectedTaskCounters, ( void * ) xTaskCounters, sizeof( xExpectedTaskCounters ) ) )
|
||
|
|
{
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
xTaskResumeAll();
|
||
|
|
|
||
|
|
/* We should have been preempted by resuming the scheduler - so by the
|
||
|
|
time we are running again we expect the high priority task to have
|
||
|
|
removed three items from the queue. */
|
||
|
|
xExpectedTaskCounters[ evtHIGHEST_PRIORITY_INDEX_1 ] += evtQUEUE_LENGTH;
|
||
|
|
if( memcmp( ( void * ) xExpectedTaskCounters, ( void * ) xTaskCounters, sizeof( xExpectedTaskCounters ) ) )
|
||
|
|
{
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* The medium priority and second high priority tasks are still
|
||
|
|
suspended. Make sure to resume them before starting again. */
|
||
|
|
vTaskResume( xCreatedTasks[ evtMEDIUM_PRIORITY_INDEX ] );
|
||
|
|
vTaskResume( xCreatedTasks[ evtHIGHEST_PRIORITY_INDEX_2 ] );
|
||
|
|
|
||
|
|
/* Just keep incrementing to show the task is still executing. */
|
||
|
|
xCheckVariable++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
/*-----------------------------------------------------------*/
|
||
|
|
|
||
|
|
static void prvCheckTaskCounters( portBASE_TYPE xExpectedTask, portBASE_TYPE xIncrement )
|
||
|
|
{
|
||
|
|
portBASE_TYPE xDummy = 0;
|
||
|
|
|
||
|
|
/* Write to the queue the requested number of times. The data written is
|
||
|
|
not important. */
|
||
|
|
for( xDummy = 0; xDummy < xIncrement; xDummy++ )
|
||
|
|
{
|
||
|
|
if( xQueueSend( xQueue, &xDummy, evtNO_DELAY ) != pdTRUE )
|
||
|
|
{
|
||
|
|
/* Did not expect to ever find the queue full. */
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* All the tasks blocked on the queue have a priority higher than the
|
||
|
|
controlling task. Writing to the queue will therefore have caused this
|
||
|
|
task to be preempted. By the time this line executes the event task will
|
||
|
|
have executed and incremented its counter. Increment the expected counter
|
||
|
|
to the same value. */
|
||
|
|
( xExpectedTaskCounters[ xExpectedTask ] ) += xIncrement;
|
||
|
|
|
||
|
|
/* Check the actual counts and expected counts really are the same. */
|
||
|
|
if( memcmp( ( void * ) xExpectedTaskCounters, ( void * ) xTaskCounters, sizeof( xExpectedTaskCounters ) ) )
|
||
|
|
{
|
||
|
|
/* The counters were not the same. This means a task we did not expect
|
||
|
|
to unblock actually did unblock. */
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
/*-----------------------------------------------------------*/
|
||
|
|
|
||
|
|
portBASE_TYPE xAreMultiEventTasksStillRunning( void )
|
||
|
|
{
|
||
|
|
static portBASE_TYPE xPreviousCheckVariable = 0;
|
||
|
|
|
||
|
|
/* Called externally to periodically check that this test is still
|
||
|
|
operational. */
|
||
|
|
|
||
|
|
if( xPreviousCheckVariable == xCheckVariable )
|
||
|
|
{
|
||
|
|
xHealthStatus = pdFAIL;
|
||
|
|
}
|
||
|
|
|
||
|
|
xPreviousCheckVariable = xCheckVariable;
|
||
|
|
|
||
|
|
return xHealthStatus;
|
||
|
|
}
|
||
|
|
|
||
|
|
|