/** * @brief A heuristic example to demonstrate how the postponed jobs are handled in EDF. * * Given two tasks with implicit deadline under EDF policy. * Task 1 has (400, 500) and task 2 has (450, 550), where (required ticks, period/deadline). * For the simplicity, we only execute the first task three times. * In the original implementation in v4.11, no matter how many periods are * expired, only one job will be released with a shifted deadline assignment. * * In this example, task 2 will be blocked by the second and third jobs * of task 1, so that there are two jobs are postponed. * Due to the domino effects, the following jobs of task 2 will be postponed until Job 9. * * If the overrun handling is correct, the period of task 2 changes back to * normal status at Job 9. * Otherwise, the release time of job 3 is no longer periodic * and there is no more postponed jobs. * */ /* * COPYRIGHT (c) 2016-2017 Kuan-Hsun Chen. * * The license and distribution terms for this file may be * found in the file LICENSE in this distribution or at * http://www.rtems.com/license/LICENSE. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include "test_support.h" const char rtems_test_name[] = "SPEDFSCHED 4"; static const uint32_t Periods[] = { 500, 550 }; static const uint32_t Iterations[] = { 400, 450 }; static const rtems_name Task_name[] = { rtems_build_name( 'T', 'A', '1', ' ' ), rtems_build_name( 'T', 'A', '2', ' ' ) }; static const rtems_task_priority Prio[3] = { 2, 5 }; static const uint32_t testnumber = 9; /* stop condition */ static uint32_t tsk_counter[] = { 0, 0 }; static rtems_id Task_id[ 2 ]; /** * @brief Task body */ static rtems_task Task( rtems_task_argument argument ) { rtems_status_code status; rtems_id RM_period; rtems_id selfid=rtems_task_self(); rtems_rate_monotonic_period_status period_status; uint32_t flag=0; /* create period */ status = rtems_rate_monotonic_create( Task_name[ argument ], &RM_period ); directive_failed( status, "rtems_rate_monotonic_create" ); while ( FOREVER ) { status = rtems_rate_monotonic_period( RM_period, Periods[ argument ] ); /* Do some work */ rtems_test_spin_for_ticks( Iterations[ argument ] ); if( argument == 1 ){ if( status == RTEMS_TIMEOUT ){ if( flag == 0 ){ puts( "First time RTEMS_TIMEOUT" ); puts( "Task 2 should have 2 postponed job due to preemption." ); rtems_test_assert( period_status.postponed_jobs_count == 2 ); flag = 1; } } else if ( flag == 1 && status == RTEMS_SUCCESSFUL ) { puts( "RTEMS_SUCCESSFUL" ); puts( "Overrun handling is finished, now Task 2 becomes normal." ); rtems_test_assert( period_status.postponed_jobs_count == 0 ); flag = 0; } /* Check the status */ status = rtems_rate_monotonic_get_status( RM_period, &period_status ); directive_failed( status, "rate_monotonic_get_status" ); if( tsk_counter[ argument ] == testnumber ){ TEST_END(); status = rtems_rate_monotonic_delete( RM_period ); directive_failed( status, "rtems_rate_monotonic_delete" ); rtems_test_exit( 0 ); } } tsk_counter[ argument ]+=1; if ( argument == 0 ){ if( tsk_counter[ argument ] == 3 ){ puts("Task 1 has released 3 jobs and finished."); status = rtems_rate_monotonic_delete( RM_period ); directive_failed( status, "rtems_rate_monotonic_delete" ); status = rtems_task_delete( selfid ); directive_failed( status, "rtems_task_delete" ); } } } } static rtems_task Init( rtems_task_argument argument ) { uint32_t index; rtems_status_code status; TEST_BEGIN(); /* Create two tasks */ for ( index = 0; index < RTEMS_ARRAY_SIZE(Task_name); ++index ){ status = rtems_task_create( Task_name[ index ], Prio[index], RTEMS_MINIMUM_STACK_SIZE, RTEMS_DEFAULT_MODES, RTEMS_DEFAULT_ATTRIBUTES, &Task_id[ index ] ); directive_failed( status, "rtems_task_create loop" ); } /* After creating the periods for tasks, start to run them sequencially. */ for ( index = 0; index < RTEMS_ARRAY_SIZE(Task_name); ++index ){ status = rtems_task_start( Task_id[ index ], Task, index); directive_failed( status, "rtems_task_start loop"); } status = rtems_task_delete( RTEMS_SELF ); directive_failed( status, "rtems_task_delete of RTEMS_SELF" ); } #define CONFIGURE_APPLICATION_NEEDS_SIMPLE_CONSOLE_DRIVER #define CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER #define CONFIGURE_MICROSECONDS_PER_TICK 1000 #define CONFIGURE_MAXIMUM_TASKS 3 #define CONFIGURE_MAXIMUM_PERIODS 2 #define CONFIGURE_RTEMS_INIT_TASKS_TABLE #define CONFIGURE_SCHEDULER_EDF #define CONFIGURE_INITIAL_EXTENSIONS \ RTEMS_TEST_INITIAL_EXTENSION #define CONFIGURE_INIT #include