FreeRTOS Real Time Operating System, Modified from Kenji Arai's initial port. See freertos.org for full documentation.
Fork of FreeRTOS_on_mbed_v1 by
tasks.c
00001 /* 00002 FreeRTOS V6.0.3 - Copyright (C) 2010 Real Time Engineers Ltd. 00003 00004 *************************************************************************** 00005 * * 00006 * If you are: * 00007 * * 00008 * + New to FreeRTOS, * 00009 * + Wanting to learn FreeRTOS or multitasking in general quickly * 00010 * + Looking for basic training, * 00011 * + Wanting to improve your FreeRTOS skills and productivity * 00012 * * 00013 * then take a look at the FreeRTOS eBook * 00014 * * 00015 * "Using the FreeRTOS Real Time Kernel - a Practical Guide" * 00016 * http://www.FreeRTOS.org/Documentation * 00017 * * 00018 * A pdf reference manual is also available. Both are usually delivered * 00019 * to your inbox within 20 minutes to two hours when purchased between 8am * 00020 * and 8pm GMT (although please allow up to 24 hours in case of * 00021 * exceptional circumstances). Thank you for your support! * 00022 * * 00023 *************************************************************************** 00024 00025 This file is part of the FreeRTOS distribution. 00026 00027 FreeRTOS is free software; you can redistribute it and/or modify it under 00028 the terms of the GNU General Public License (version 2) as published by the 00029 Free Software Foundation AND MODIFIED BY the FreeRTOS exception. 00030 ***NOTE*** The exception to the GPL is included to allow you to distribute 00031 a combined work that includes FreeRTOS without being obliged to provide the 00032 source code for proprietary components outside of the FreeRTOS kernel. 00033 FreeRTOS is distributed in the hope that it will be useful, but WITHOUT 00034 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 00035 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 00036 more details. You should have received a copy of the GNU General Public 00037 License and the FreeRTOS license exception along with FreeRTOS; if not it 00038 can be viewed here: http://www.freertos.org/a00114.html and also obtained 00039 by writing to Richard Barry, contact details for whom are available on the 00040 FreeRTOS WEB site. 00041 00042 1 tab == 4 spaces! 00043 00044 http://www.FreeRTOS.org - Documentation, latest information, license and 00045 contact details. 00046 00047 http://www.SafeRTOS.com - A version that is certified for use in safety 00048 critical systems. 00049 00050 http://www.OpenRTOS.com - Commercial support, development, porting, 00051 licensing and training services. 00052 */ 00053 00054 00055 #include <stdio.h> 00056 #include <stdlib.h> 00057 #include <string.h> 00058 00059 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining 00060 all the API functions to use the MPU wrappers. That should only be done when 00061 task.h is included from an application file. */ 00062 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE 00063 00064 #include "FreeRTOS.h" 00065 #include "task.h" 00066 #include "StackMacros.h" 00067 00068 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE 00069 00070 #if 0 00071 /* 00072 * Macro to define the amount of stack available to the idle task. 00073 */ 00074 #define tskIDLE_STACK_SIZE configMINIMAL_STACK_SIZE 00075 #endif 00076 00077 /* 00078 * Task control block. A task control block (TCB) is allocated to each task, 00079 * and stores the context of the task. 00080 */ 00081 typedef struct tskTaskControlBlock 00082 { 00083 volatile portSTACK_TYPE *pxTopOfStack; /*< Points to the location of the last item placed on the tasks stack. THIS MUST BE THE FIRST MEMBER OF THE STRUCT. */ 00084 00085 #if ( portUSING_MPU_WRAPPERS == 1 ) 00086 xMPU_SETTINGS xMPUSettings; /*< The MPU settings are defined as part of the port layer. THIS MUST BE THE SECOND MEMBER OF THE STRUCT. */ 00087 #endif 00088 00089 xListItem xGenericListItem; /*< List item used to place the TCB in ready and blocked queues. */ 00090 xListItem xEventListItem; /*< List item used to place the TCB in event lists. */ 00091 unsigned portBASE_TYPE uxPriority; /*< The priority of the task where 0 is the lowest priority. */ 00092 portSTACK_TYPE *pxStack; /*< Points to the start of the stack. */ 00093 signed char pcTaskName[ configMAX_TASK_NAME_LEN ];/*< Descriptive name given to the task when created. Facilitates debugging only. */ 00094 00095 #if ( portSTACK_GROWTH > 0 ) 00096 portSTACK_TYPE *pxEndOfStack; /*< Used for stack overflow checking on architectures where the stack grows up from low memory. */ 00097 #endif 00098 00099 #if ( portCRITICAL_NESTING_IN_TCB == 1 ) 00100 unsigned portBASE_TYPE uxCriticalNesting; 00101 #endif 00102 00103 #if ( configUSE_TRACE_FACILITY == 1 ) 00104 unsigned portBASE_TYPE uxTCBNumber; /*< This is used for tracing the scheduler and making debugging easier only. */ 00105 #endif 00106 00107 #if ( configUSE_MUTEXES == 1 ) 00108 unsigned portBASE_TYPE uxBasePriority; /*< The priority last assigned to the task - used by the priority inheritance mechanism. */ 00109 #endif 00110 00111 #if ( configUSE_APPLICATION_TASK_TAG == 1 ) 00112 pdTASK_HOOK_CODE pxTaskTag; 00113 #endif 00114 00115 #if ( configGENERATE_RUN_TIME_STATS == 1 ) 00116 unsigned long ulRunTimeCounter; /*< Used for calculating how much CPU time each task is utilising. */ 00117 #endif 00118 00119 } tskTCB; 00120 00121 00122 /* 00123 * Some kernel aware debuggers require data to be viewed to be global, rather 00124 * than file scope. 00125 */ 00126 #ifdef portREMOVE_STATIC_QUALIFIER 00127 #define static 00128 #endif 00129 00130 /*lint -e956 */ 00131 PRIVILEGED_DATA tskTCB * volatile pxCurrentTCB = NULL; 00132 00133 /* Lists for ready and blocked tasks. --------------------*/ 00134 00135 PRIVILEGED_DATA static xList pxReadyTasksLists[ configMAX_PRIORITIES ]; /*< Prioritised ready tasks. */ 00136 PRIVILEGED_DATA static xList xDelayedTaskList1; /*< Delayed tasks. */ 00137 PRIVILEGED_DATA static xList xDelayedTaskList2; /*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */ 00138 PRIVILEGED_DATA static xList * volatile pxDelayedTaskList ; /*< Points to the delayed task list currently being used. */ 00139 PRIVILEGED_DATA static xList * volatile pxOverflowDelayedTaskList; /*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */ 00140 PRIVILEGED_DATA static xList xPendingReadyList; /*< Tasks that have been readied while the scheduler was suspended. They will be moved to the ready queue when the scheduler is resumed. */ 00141 00142 #if ( INCLUDE_vTaskDelete == 1 ) 00143 00144 PRIVILEGED_DATA static volatile xList xTasksWaitingTermination; /*< Tasks that have been deleted - but the their memory not yet freed. */ 00145 PRIVILEGED_DATA static volatile unsigned portBASE_TYPE uxTasksDeleted = ( unsigned portBASE_TYPE ) 0; 00146 00147 #endif 00148 00149 #if ( INCLUDE_vTaskSuspend == 1 ) 00150 00151 PRIVILEGED_DATA static xList xSuspendedTaskList; /*< Tasks that are currently suspended. */ 00152 00153 #endif 00154 00155 /* File private variables. --------------------------------*/ 00156 PRIVILEGED_DATA static volatile unsigned portBASE_TYPE uxCurrentNumberOfTasks = ( unsigned portBASE_TYPE ) 0; 00157 PRIVILEGED_DATA static volatile portTickType xTickCount = ( portTickType ) 0; 00158 PRIVILEGED_DATA static unsigned portBASE_TYPE uxTopUsedPriority = tskIDLE_PRIORITY; 00159 PRIVILEGED_DATA static volatile unsigned portBASE_TYPE uxTopReadyPriority = tskIDLE_PRIORITY; 00160 PRIVILEGED_DATA static volatile signed portBASE_TYPE xSchedulerRunning = pdFALSE; 00161 PRIVILEGED_DATA static volatile unsigned portBASE_TYPE uxSchedulerSuspended = ( unsigned portBASE_TYPE ) pdFALSE; 00162 PRIVILEGED_DATA static volatile unsigned portBASE_TYPE uxMissedTicks = ( unsigned portBASE_TYPE ) 0; 00163 PRIVILEGED_DATA static volatile portBASE_TYPE xMissedYield = ( portBASE_TYPE ) pdFALSE; 00164 PRIVILEGED_DATA static volatile portBASE_TYPE xNumOfOverflows = ( portBASE_TYPE ) 0; 00165 PRIVILEGED_DATA static unsigned portBASE_TYPE uxTaskNumber = ( unsigned portBASE_TYPE ) 0; 00166 00167 #if ( configGENERATE_RUN_TIME_STATS == 1 ) 00168 00169 PRIVILEGED_DATA static char pcStatsString[ 50 ] ; 00170 PRIVILEGED_DATA static unsigned long ulTaskSwitchedInTime = 0UL; /*< Holds the value of a timer/counter the last time a task was switched in. */ 00171 static void prvGenerateRunTimeStatsForTasksInList( const signed char *pcWriteBuffer, xList *pxList, unsigned long ulTotalRunTime ) PRIVILEGED_FUNCTION; 00172 00173 #endif 00174 00175 /* Debugging and trace facilities private variables and macros. ------------*/ 00176 00177 /* 00178 * The value used to fill the stack of a task when the task is created. This 00179 * is used purely for checking the high water mark for tasks. 00180 */ 00181 #define tskSTACK_FILL_BYTE ( 0xa5 ) 00182 00183 /* 00184 * Macros used by vListTask to indicate which state a task is in. 00185 */ 00186 #define tskBLOCKED_CHAR ( ( signed char ) 'B' ) 00187 #define tskREADY_CHAR ( ( signed char ) 'R' ) 00188 #define tskDELETED_CHAR ( ( signed char ) 'D' ) 00189 #define tskSUSPENDED_CHAR ( ( signed char ) 'S' ) 00190 00191 /* 00192 * Macros and private variables used by the trace facility. 00193 */ 00194 #if ( configUSE_TRACE_FACILITY == 1 ) 00195 00196 #define tskSIZE_OF_EACH_TRACE_LINE ( ( unsigned long ) ( sizeof( unsigned long ) + sizeof( unsigned long ) ) ) 00197 PRIVILEGED_DATA static volatile signed char * volatile pcTraceBuffer; 00198 PRIVILEGED_DATA static signed char *pcTraceBufferStart; 00199 PRIVILEGED_DATA static signed char *pcTraceBufferEnd; 00200 PRIVILEGED_DATA static signed portBASE_TYPE xTracing = pdFALSE; 00201 static unsigned portBASE_TYPE uxPreviousTask = 255; 00202 PRIVILEGED_DATA static char pcStatusString[ 50 ]; 00203 00204 #endif 00205 00206 /*-----------------------------------------------------------*/ 00207 00208 /* 00209 * Macro that writes a trace of scheduler activity to a buffer. This trace 00210 * shows which task is running when and is very useful as a debugging tool. 00211 * As this macro is called each context switch it is a good idea to undefine 00212 * it if not using the facility. 00213 */ 00214 #if ( configUSE_TRACE_FACILITY == 1 ) 00215 00216 #define vWriteTraceToBuffer() \ 00217 { \ 00218 if( xTracing ) \ 00219 { \ 00220 if( uxPreviousTask != pxCurrentTCB->uxTCBNumber ) \ 00221 { \ 00222 if( ( pcTraceBuffer + tskSIZE_OF_EACH_TRACE_LINE ) < pcTraceBufferEnd ) \ 00223 { \ 00224 uxPreviousTask = pxCurrentTCB->uxTCBNumber; \ 00225 *( unsigned long * ) pcTraceBuffer = ( unsigned long ) xTickCount; \ 00226 pcTraceBuffer += sizeof( unsigned long ); \ 00227 *( unsigned long * ) pcTraceBuffer = ( unsigned long ) uxPreviousTask; \ 00228 pcTraceBuffer += sizeof( unsigned long ); \ 00229 } \ 00230 else \ 00231 { \ 00232 xTracing = pdFALSE; \ 00233 } \ 00234 } \ 00235 } \ 00236 } 00237 00238 #else 00239 00240 #define vWriteTraceToBuffer() 00241 00242 #endif 00243 /*-----------------------------------------------------------*/ 00244 00245 /* 00246 * Place the task represented by pxTCB into the appropriate ready queue for 00247 * the task. It is inserted at the end of the list. One quirk of this is 00248 * that if the task being inserted is at the same priority as the currently 00249 * executing task, then it will only be rescheduled after the currently 00250 * executing task has been rescheduled. 00251 */ 00252 #define prvAddTaskToReadyQueue( pxTCB ) \ 00253 { \ 00254 if( pxTCB->uxPriority > uxTopReadyPriority ) \ 00255 { \ 00256 uxTopReadyPriority = pxTCB->uxPriority; \ 00257 } \ 00258 vListInsertEnd( ( xList * ) &( pxReadyTasksLists[ pxTCB->uxPriority ] ), &( pxTCB->xGenericListItem ) ); \ 00259 } 00260 /*-----------------------------------------------------------*/ 00261 00262 /* 00263 * Macro that looks at the list of tasks that are currently delayed to see if 00264 * any require waking. 00265 * 00266 * Tasks are stored in the queue in the order of their wake time - meaning 00267 * once one tasks has been found whose timer has not expired we need not look 00268 * any further down the list. 00269 */ 00270 #define prvCheckDelayedTasks() \ 00271 { \ 00272 register tskTCB *pxTCB; \ 00273 \ 00274 while( ( pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxDelayedTaskList ) ) != NULL ) \ 00275 { \ 00276 if( xTickCount < listGET_LIST_ITEM_VALUE( &( pxTCB->xGenericListItem ) ) ) \ 00277 { \ 00278 break; \ 00279 } \ 00280 vListRemove( &( pxTCB->xGenericListItem ) ); \ 00281 /* Is the task waiting on an event also? */ \ 00282 if( pxTCB->xEventListItem.pvContainer ) \ 00283 { \ 00284 vListRemove( &( pxTCB->xEventListItem ) ); \ 00285 } \ 00286 prvAddTaskToReadyQueue( pxTCB ); \ 00287 } \ 00288 } 00289 /*-----------------------------------------------------------*/ 00290 00291 /* 00292 * Several functions take an xTaskHandle parameter that can optionally be NULL, 00293 * where NULL is used to indicate that the handle of the currently executing 00294 * task should be used in place of the parameter. This macro simply checks to 00295 * see if the parameter is NULL and returns a pointer to the appropriate TCB. 00296 */ 00297 #define prvGetTCBFromHandle( pxHandle ) ( ( pxHandle == NULL ) ? ( tskTCB * ) pxCurrentTCB : ( tskTCB * ) pxHandle ) 00298 00299 00300 /* File private functions. --------------------------------*/ 00301 00302 /* 00303 * Utility to ready a TCB for a given task. Mainly just copies the parameters 00304 * into the TCB structure. 00305 */ 00306 static void prvInitialiseTCBVariables( tskTCB *pxTCB, const signed char * const pcName, unsigned portBASE_TYPE uxPriority, const xMemoryRegion * const xRegions, unsigned short usStackDepth ) PRIVILEGED_FUNCTION; 00307 00308 /* 00309 * Utility to ready all the lists used by the scheduler. This is called 00310 * automatically upon the creation of the first task. 00311 */ 00312 static void prvInitialiseTaskLists( void ) PRIVILEGED_FUNCTION; 00313 00314 /* 00315 * The idle task, which as all tasks is implemented as a never ending loop. 00316 * The idle task is automatically created and added to the ready lists upon 00317 * creation of the first user task. 00318 * 00319 * The portTASK_FUNCTION_PROTO() macro is used to allow port/compiler specific 00320 * language extensions. The equivalent prototype for this function is: 00321 * 00322 * void prvIdleTask( void *pvParameters ); 00323 * 00324 */ 00325 //static portTASK_FUNCTION_PROTO( prvIdleTask, pvParameters ); 00326 #ifdef __cplusplus 00327 extern "C" { 00328 #endif 00329 static portTASK_FUNCTION_PROTO( prvIdleTask, pvParameters ); 00330 #ifdef __cplusplus 00331 } 00332 #endif 00333 /* 00334 * Utility to free all memory allocated by the scheduler to hold a TCB, 00335 * including the stack pointed to by the TCB. 00336 * 00337 * This does not free memory allocated by the task itself (i.e. memory 00338 * allocated by calls to pvPortMalloc from within the tasks application code). 00339 */ 00340 #if ( ( INCLUDE_vTaskDelete == 1 ) || ( INCLUDE_vTaskCleanUpResources == 1 ) ) 00341 00342 static void prvDeleteTCB( tskTCB *pxTCB ) PRIVILEGED_FUNCTION; 00343 00344 #endif 00345 00346 /* 00347 * Used only by the idle task. This checks to see if anything has been placed 00348 * in the list of tasks waiting to be deleted. If so the task is cleaned up 00349 * and its TCB deleted. 00350 */ 00351 static void prvCheckTasksWaitingTermination( void ) PRIVILEGED_FUNCTION; 00352 00353 /* 00354 * Allocates memory from the heap for a TCB and associated stack. Checks the 00355 * allocation was successful. 00356 */ 00357 static tskTCB *prvAllocateTCBAndStack( unsigned short usStackDepth, portSTACK_TYPE *puxStackBuffer ) PRIVILEGED_FUNCTION; 00358 00359 /* 00360 * Called from vTaskList. vListTasks details all the tasks currently under 00361 * control of the scheduler. The tasks may be in one of a number of lists. 00362 * prvListTaskWithinSingleList accepts a list and details the tasks from 00363 * within just that list. 00364 * 00365 * THIS FUNCTION IS INTENDED FOR DEBUGGING ONLY, AND SHOULD NOT BE CALLED FROM 00366 * NORMAL APPLICATION CODE. 00367 */ 00368 #if ( configUSE_TRACE_FACILITY == 1 ) 00369 00370 static void prvListTaskWithinSingleList( const signed char *pcWriteBuffer, xList *pxList, signed char cStatus ) PRIVILEGED_FUNCTION; 00371 00372 #endif 00373 00374 /* 00375 * When a task is created, the stack of the task is filled with a known value. 00376 * This function determines the 'high water mark' of the task stack by 00377 * determining how much of the stack remains at the original preset value. 00378 */ 00379 #if ( ( configUSE_TRACE_FACILITY == 1 ) || ( INCLUDE_uxTaskGetStackHighWaterMark == 1 ) ) 00380 00381 static unsigned short usTaskCheckFreeStackSpace( const unsigned char * pucStackByte ) PRIVILEGED_FUNCTION; 00382 00383 #endif 00384 00385 00386 /*lint +e956 */ 00387 00388 00389 00390 /*----------------------------------------------------------- 00391 * TASK CREATION API documented in task.h 00392 *----------------------------------------------------------*/ 00393 00394 signed portBASE_TYPE xTaskGenericCreate( pdTASK_CODE pxTaskCode, const signed char * const pcName, unsigned short usStackDepth, void *pvParameters, unsigned portBASE_TYPE uxPriority, xTaskHandle *pxCreatedTask, portSTACK_TYPE *puxStackBuffer, const xMemoryRegion * const xRegions ) 00395 { 00396 signed portBASE_TYPE xReturn; 00397 tskTCB * pxNewTCB; 00398 00399 /* Allocate the memory required by the TCB and stack for the new task, 00400 checking that the allocation was successful. */ 00401 pxNewTCB = prvAllocateTCBAndStack( usStackDepth, puxStackBuffer ); 00402 00403 if( pxNewTCB != NULL ) 00404 { 00405 portSTACK_TYPE *pxTopOfStack; 00406 00407 #if( portUSING_MPU_WRAPPERS == 1 ) 00408 /* Should the task be created in privileged mode? */ 00409 portBASE_TYPE xRunPrivileged; 00410 if( ( uxPriority & portPRIVILEGE_BIT ) != 0x00 ) 00411 { 00412 xRunPrivileged = pdTRUE; 00413 } 00414 else 00415 { 00416 xRunPrivileged = pdFALSE; 00417 } 00418 uxPriority &= ~portPRIVILEGE_BIT; 00419 #endif /* portUSING_MPU_WRAPPERS == 1 */ 00420 00421 /* Calculate the top of stack address. This depends on whether the 00422 stack grows from high memory to low (as per the 80x86) or visa versa. 00423 portSTACK_GROWTH is used to make the result positive or negative as 00424 required by the port. */ 00425 #if( portSTACK_GROWTH < 0 ) 00426 { 00427 pxTopOfStack = pxNewTCB->pxStack + ( usStackDepth - 1 ); 00428 pxTopOfStack = ( portSTACK_TYPE * ) ( ( ( unsigned long ) pxTopOfStack ) & ( ( unsigned long ) ~portBYTE_ALIGNMENT_MASK ) ); 00429 } 00430 #else 00431 { 00432 pxTopOfStack = pxNewTCB->pxStack; 00433 00434 /* If we want to use stack checking on architectures that use 00435 a positive stack growth direction then we also need to store the 00436 other extreme of the stack space. */ 00437 pxNewTCB->pxEndOfStack = pxNewTCB->pxStack + ( usStackDepth - 1 ); 00438 } 00439 #endif 00440 00441 /* Setup the newly allocated TCB with the initial state of the task. */ 00442 prvInitialiseTCBVariables( pxNewTCB, pcName, uxPriority, xRegions, usStackDepth ); 00443 00444 /* Initialize the TCB stack to look as if the task was already running, 00445 but had been interrupted by the scheduler. The return address is set 00446 to the start of the task function. Once the stack has been initialised 00447 the top of stack variable is updated. */ 00448 #if( portUSING_MPU_WRAPPERS == 1 ) 00449 { 00450 pxNewTCB->pxTopOfStack = pxPortInitialiseStack( pxTopOfStack, pxTaskCode, pvParameters, xRunPrivileged ); 00451 } 00452 #else 00453 { 00454 pxNewTCB->pxTopOfStack = pxPortInitialiseStack( pxTopOfStack, pxTaskCode, pvParameters ); 00455 } 00456 #endif 00457 00458 /* We are going to manipulate the task queues to add this task to a 00459 ready list, so must make sure no interrupts occur. */ 00460 portENTER_CRITICAL(); 00461 { 00462 uxCurrentNumberOfTasks++; 00463 if( uxCurrentNumberOfTasks == ( unsigned portBASE_TYPE ) 1 ) 00464 { 00465 /* As this is the first task it must also be the current task. */ 00466 pxCurrentTCB = pxNewTCB; 00467 00468 /* This is the first task to be created so do the preliminary 00469 initialisation required. We will not recover if this call 00470 fails, but we will report the failure. */ 00471 prvInitialiseTaskLists(); 00472 } 00473 else 00474 { 00475 /* If the scheduler is not already running, make this task the 00476 current task if it is the highest priority task to be created 00477 so far. */ 00478 if( xSchedulerRunning == pdFALSE ) 00479 { 00480 if( pxCurrentTCB->uxPriority <= uxPriority ) 00481 { 00482 pxCurrentTCB = pxNewTCB; 00483 } 00484 } 00485 } 00486 00487 /* Remember the top priority to make context switching faster. Use 00488 the priority in pxNewTCB as this has been capped to a valid value. */ 00489 if( pxNewTCB->uxPriority > uxTopUsedPriority ) 00490 { 00491 uxTopUsedPriority = pxNewTCB->uxPriority; 00492 } 00493 00494 #if ( configUSE_TRACE_FACILITY == 1 ) 00495 { 00496 /* Add a counter into the TCB for tracing only. */ 00497 pxNewTCB->uxTCBNumber = uxTaskNumber; 00498 } 00499 #endif 00500 uxTaskNumber++; 00501 00502 prvAddTaskToReadyQueue( pxNewTCB ); 00503 00504 xReturn = pdPASS; 00505 traceTASK_CREATE( pxNewTCB ); 00506 } 00507 portEXIT_CRITICAL(); 00508 } 00509 else 00510 { 00511 xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY; 00512 traceTASK_CREATE_FAILED( pxNewTCB ); 00513 } 00514 00515 if( xReturn == pdPASS ) 00516 { 00517 if( ( void * ) pxCreatedTask != NULL ) 00518 { 00519 /* Pass the TCB out - in an anonymous way. The calling function/ 00520 task can use this as a handle to delete the task later if 00521 required.*/ 00522 *pxCreatedTask = ( xTaskHandle ) pxNewTCB; 00523 } 00524 00525 if( xSchedulerRunning != pdFALSE ) 00526 { 00527 /* If the created task is of a higher priority than the current task 00528 then it should run now. */ 00529 if( pxCurrentTCB->uxPriority < uxPriority ) 00530 { 00531 portYIELD_WITHIN_API(); 00532 } 00533 } 00534 } 00535 00536 return xReturn; 00537 } 00538 /*-----------------------------------------------------------*/ 00539 00540 #if ( INCLUDE_vTaskDelete == 1 ) 00541 00542 void vTaskDelete( xTaskHandle pxTaskToDelete ) 00543 { 00544 tskTCB *pxTCB; 00545 00546 portENTER_CRITICAL(); 00547 { 00548 /* Ensure a yield is performed if the current task is being 00549 deleted. */ 00550 if( pxTaskToDelete == pxCurrentTCB ) 00551 { 00552 pxTaskToDelete = NULL; 00553 } 00554 00555 /* If null is passed in here then we are deleting ourselves. */ 00556 pxTCB = prvGetTCBFromHandle( pxTaskToDelete ); 00557 00558 /* Remove task from the ready list and place in the termination list. 00559 This will stop the task from be scheduled. The idle task will check 00560 the termination list and free up any memory allocated by the 00561 scheduler for the TCB and stack. */ 00562 vListRemove( &( pxTCB->xGenericListItem ) ); 00563 00564 /* Is the task waiting on an event also? */ 00565 if( pxTCB->xEventListItem.pvContainer ) 00566 { 00567 vListRemove( &( pxTCB->xEventListItem ) ); 00568 } 00569 00570 vListInsertEnd( ( xList * ) &xTasksWaitingTermination, &( pxTCB->xGenericListItem ) ); 00571 00572 /* Increment the ucTasksDeleted variable so the idle task knows 00573 there is a task that has been deleted and that it should therefore 00574 check the xTasksWaitingTermination list. */ 00575 ++uxTasksDeleted; 00576 00577 /* Increment the uxTaskNumberVariable also so kernel aware debuggers 00578 can detect that the task lists need re-generating. */ 00579 uxTaskNumber++; 00580 00581 traceTASK_DELETE( pxTCB ); 00582 } 00583 portEXIT_CRITICAL(); 00584 00585 /* Force a reschedule if we have just deleted the current task. */ 00586 if( xSchedulerRunning != pdFALSE ) 00587 { 00588 if( ( void * ) pxTaskToDelete == NULL ) 00589 { 00590 portYIELD_WITHIN_API(); 00591 } 00592 } 00593 } 00594 00595 #endif 00596 00597 00598 00599 00600 00601 00602 /*----------------------------------------------------------- 00603 * TASK CONTROL API documented in task.h 00604 *----------------------------------------------------------*/ 00605 00606 #if ( INCLUDE_vTaskDelayUntil == 1 ) 00607 00608 void vTaskDelayUntil( portTickType * const pxPreviousWakeTime, portTickType xTimeIncrement ) 00609 { 00610 portTickType xTimeToWake; 00611 portBASE_TYPE xAlreadyYielded, xShouldDelay = pdFALSE; 00612 00613 vTaskSuspendAll(); 00614 { 00615 /* Generate the tick time at which the task wants to wake. */ 00616 xTimeToWake = *pxPreviousWakeTime + xTimeIncrement; 00617 00618 if( xTickCount < *pxPreviousWakeTime ) 00619 { 00620 /* The tick count has overflowed since this function was 00621 lasted called. In this case the only time we should ever 00622 actually delay is if the wake time has also overflowed, 00623 and the wake time is greater than the tick time. When this 00624 is the case it is as if neither time had overflowed. */ 00625 if( ( xTimeToWake < *pxPreviousWakeTime ) && ( xTimeToWake > xTickCount ) ) 00626 { 00627 xShouldDelay = pdTRUE; 00628 } 00629 } 00630 else 00631 { 00632 /* The tick time has not overflowed. In this case we will 00633 delay if either the wake time has overflowed, and/or the 00634 tick time is less than the wake time. */ 00635 if( ( xTimeToWake < *pxPreviousWakeTime ) || ( xTimeToWake > xTickCount ) ) 00636 { 00637 xShouldDelay = pdTRUE; 00638 } 00639 } 00640 00641 /* Update the wake time ready for the next call. */ 00642 *pxPreviousWakeTime = xTimeToWake; 00643 00644 if( xShouldDelay ) 00645 { 00646 traceTASK_DELAY_UNTIL(); 00647 00648 /* We must remove ourselves from the ready list before adding 00649 ourselves to the blocked list as the same list item is used for 00650 both lists. */ 00651 vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 00652 00653 /* The list item will be inserted in wake time order. */ 00654 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake ); 00655 00656 if( xTimeToWake < xTickCount ) 00657 { 00658 /* Wake time has overflowed. Place this item in the 00659 overflow list. */ 00660 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 00661 } 00662 else 00663 { 00664 /* The wake time has not overflowed, so we can use the 00665 current block list. */ 00666 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 00667 } 00668 } 00669 } 00670 xAlreadyYielded = xTaskResumeAll(); 00671 00672 /* Force a reschedule if xTaskResumeAll has not already done so, we may 00673 have put ourselves to sleep. */ 00674 if( !xAlreadyYielded ) 00675 { 00676 portYIELD_WITHIN_API(); 00677 } 00678 } 00679 00680 #endif 00681 /*-----------------------------------------------------------*/ 00682 00683 #if ( INCLUDE_vTaskDelay == 1 ) 00684 00685 void vTaskDelay( portTickType xTicksToDelay ) 00686 { 00687 portTickType xTimeToWake; 00688 signed portBASE_TYPE xAlreadyYielded = pdFALSE; 00689 00690 /* A delay time of zero just forces a reschedule. */ 00691 if( xTicksToDelay > ( portTickType ) 0 ) 00692 { 00693 vTaskSuspendAll(); 00694 { 00695 traceTASK_DELAY(); 00696 00697 /* A task that is removed from the event list while the 00698 scheduler is suspended will not get placed in the ready 00699 list or removed from the blocked list until the scheduler 00700 is resumed. 00701 00702 This task cannot be in an event list as it is the currently 00703 executing task. */ 00704 00705 /* Calculate the time to wake - this may overflow but this is 00706 not a problem. */ 00707 xTimeToWake = xTickCount + xTicksToDelay; 00708 00709 /* We must remove ourselves from the ready list before adding 00710 ourselves to the blocked list as the same list item is used for 00711 both lists. */ 00712 vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 00713 00714 /* The list item will be inserted in wake time order. */ 00715 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake ); 00716 00717 if( xTimeToWake < xTickCount ) 00718 { 00719 /* Wake time has overflowed. Place this item in the 00720 overflow list. */ 00721 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 00722 } 00723 else 00724 { 00725 /* The wake time has not overflowed, so we can use the 00726 current block list. */ 00727 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 00728 } 00729 } 00730 xAlreadyYielded = xTaskResumeAll(); 00731 } 00732 00733 /* Force a reschedule if xTaskResumeAll has not already done so, we may 00734 have put ourselves to sleep. */ 00735 if( !xAlreadyYielded ) 00736 { 00737 portYIELD_WITHIN_API(); 00738 } 00739 } 00740 00741 #endif 00742 /*-----------------------------------------------------------*/ 00743 00744 #if ( INCLUDE_uxTaskPriorityGet == 1 ) 00745 00746 unsigned portBASE_TYPE uxTaskPriorityGet( xTaskHandle pxTask ) 00747 { 00748 tskTCB *pxTCB; 00749 unsigned portBASE_TYPE uxReturn; 00750 00751 portENTER_CRITICAL(); 00752 { 00753 /* If null is passed in here then we are changing the 00754 priority of the calling function. */ 00755 pxTCB = prvGetTCBFromHandle( pxTask ); 00756 uxReturn = pxTCB->uxPriority; 00757 } 00758 portEXIT_CRITICAL(); 00759 00760 return uxReturn; 00761 } 00762 00763 #endif 00764 /*-----------------------------------------------------------*/ 00765 00766 #if ( INCLUDE_vTaskPrioritySet == 1 ) 00767 00768 void vTaskPrioritySet( xTaskHandle pxTask, unsigned portBASE_TYPE uxNewPriority ) 00769 { 00770 tskTCB *pxTCB; 00771 unsigned portBASE_TYPE uxCurrentPriority, xYieldRequired = pdFALSE; 00772 00773 /* Ensure the new priority is valid. */ 00774 if( uxNewPriority >= configMAX_PRIORITIES ) 00775 { 00776 uxNewPriority = configMAX_PRIORITIES - 1; 00777 } 00778 00779 portENTER_CRITICAL(); 00780 { 00781 if( pxTask == pxCurrentTCB ) 00782 { 00783 pxTask = NULL; 00784 } 00785 00786 /* If null is passed in here then we are changing the 00787 priority of the calling function. */ 00788 pxTCB = prvGetTCBFromHandle( pxTask ); 00789 00790 traceTASK_PRIORITY_SET( pxTask, uxNewPriority ); 00791 00792 #if ( configUSE_MUTEXES == 1 ) 00793 { 00794 uxCurrentPriority = pxTCB->uxBasePriority; 00795 } 00796 #else 00797 { 00798 uxCurrentPriority = pxTCB->uxPriority; 00799 } 00800 #endif 00801 00802 if( uxCurrentPriority != uxNewPriority ) 00803 { 00804 /* The priority change may have readied a task of higher 00805 priority than the calling task. */ 00806 if( uxNewPriority > uxCurrentPriority ) 00807 { 00808 if( pxTask != NULL ) 00809 { 00810 /* The priority of another task is being raised. If we 00811 were raising the priority of the currently running task 00812 there would be no need to switch as it must have already 00813 been the highest priority task. */ 00814 xYieldRequired = pdTRUE; 00815 } 00816 } 00817 else if( pxTask == NULL ) 00818 { 00819 /* Setting our own priority down means there may now be another 00820 task of higher priority that is ready to execute. */ 00821 xYieldRequired = pdTRUE; 00822 } 00823 00824 00825 00826 #if ( configUSE_MUTEXES == 1 ) 00827 { 00828 /* Only change the priority being used if the task is not 00829 currently using an inherited priority. */ 00830 if( pxTCB->uxBasePriority == pxTCB->uxPriority ) 00831 { 00832 pxTCB->uxPriority = uxNewPriority; 00833 } 00834 00835 /* The base priority gets set whatever. */ 00836 pxTCB->uxBasePriority = uxNewPriority; 00837 } 00838 #else 00839 { 00840 pxTCB->uxPriority = uxNewPriority; 00841 } 00842 #endif 00843 00844 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), ( configMAX_PRIORITIES - ( portTickType ) uxNewPriority ) ); 00845 00846 /* If the task is in the blocked or suspended list we need do 00847 nothing more than change it's priority variable. However, if 00848 the task is in a ready list it needs to be removed and placed 00849 in the queue appropriate to its new priority. */ 00850 if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ uxCurrentPriority ] ), &( pxTCB->xGenericListItem ) ) ) 00851 { 00852 /* The task is currently in its ready list - remove before adding 00853 it to it's new ready list. As we are in a critical section we 00854 can do this even if the scheduler is suspended. */ 00855 vListRemove( &( pxTCB->xGenericListItem ) ); 00856 prvAddTaskToReadyQueue( pxTCB ); 00857 } 00858 00859 if( xYieldRequired == pdTRUE ) 00860 { 00861 portYIELD_WITHIN_API(); 00862 } 00863 } 00864 } 00865 portEXIT_CRITICAL(); 00866 } 00867 00868 #endif 00869 /*-----------------------------------------------------------*/ 00870 00871 #if ( INCLUDE_vTaskSuspend == 1 ) 00872 00873 void vTaskSuspend( xTaskHandle pxTaskToSuspend ) 00874 { 00875 tskTCB *pxTCB; 00876 00877 portENTER_CRITICAL(); 00878 { 00879 /* Ensure a yield is performed if the current task is being 00880 suspended. */ 00881 if( pxTaskToSuspend == pxCurrentTCB ) 00882 { 00883 pxTaskToSuspend = NULL; 00884 } 00885 00886 /* If null is passed in here then we are suspending ourselves. */ 00887 pxTCB = prvGetTCBFromHandle( pxTaskToSuspend ); 00888 00889 traceTASK_SUSPEND( pxTCB ); 00890 00891 /* Remove task from the ready/delayed list and place in the suspended list. */ 00892 vListRemove( &( pxTCB->xGenericListItem ) ); 00893 00894 /* Is the task waiting on an event also? */ 00895 if( pxTCB->xEventListItem.pvContainer ) 00896 { 00897 vListRemove( &( pxTCB->xEventListItem ) ); 00898 } 00899 00900 vListInsertEnd( ( xList * ) &xSuspendedTaskList, &( pxTCB->xGenericListItem ) ); 00901 } 00902 portEXIT_CRITICAL(); 00903 00904 /* We may have just suspended the current task. */ 00905 if( ( void * ) pxTaskToSuspend == NULL ) 00906 { 00907 portYIELD_WITHIN_API(); 00908 } 00909 } 00910 00911 #endif 00912 /*-----------------------------------------------------------*/ 00913 00914 #if ( INCLUDE_vTaskSuspend == 1 ) 00915 00916 signed portBASE_TYPE xTaskIsTaskSuspended( xTaskHandle xTask ) 00917 { 00918 portBASE_TYPE xReturn = pdFALSE; 00919 const tskTCB * const pxTCB = ( tskTCB * ) xTask; 00920 00921 /* Is the task we are attempting to resume actually in the 00922 suspended list? */ 00923 if( listIS_CONTAINED_WITHIN( &xSuspendedTaskList, &( pxTCB->xGenericListItem ) ) != pdFALSE ) 00924 { 00925 /* Has the task already been resumed from within an ISR? */ 00926 if( listIS_CONTAINED_WITHIN( &xPendingReadyList, &( pxTCB->xEventListItem ) ) != pdTRUE ) 00927 { 00928 /* Is it in the suspended list because it is in the 00929 Suspended state? It is possible to be in the suspended 00930 list because it is blocked on a task with no timeout 00931 specified. */ 00932 if( listIS_CONTAINED_WITHIN( NULL, &( pxTCB->xEventListItem ) ) == pdTRUE ) 00933 { 00934 xReturn = pdTRUE; 00935 } 00936 } 00937 } 00938 00939 return xReturn; 00940 } 00941 00942 #endif 00943 /*-----------------------------------------------------------*/ 00944 00945 #if ( INCLUDE_vTaskSuspend == 1 ) 00946 00947 void vTaskResume( xTaskHandle pxTaskToResume ) 00948 { 00949 tskTCB *pxTCB; 00950 00951 /* Remove the task from whichever list it is currently in, and place 00952 it in the ready list. */ 00953 pxTCB = ( tskTCB * ) pxTaskToResume; 00954 00955 /* The parameter cannot be NULL as it is impossible to resume the 00956 currently executing task. */ 00957 if( ( pxTCB != NULL ) && ( pxTCB != pxCurrentTCB ) ) 00958 { 00959 portENTER_CRITICAL(); 00960 { 00961 if( xTaskIsTaskSuspended( pxTCB ) == pdTRUE ) 00962 { 00963 traceTASK_RESUME( pxTCB ); 00964 00965 /* As we are in a critical section we can access the ready 00966 lists even if the scheduler is suspended. */ 00967 vListRemove( &( pxTCB->xGenericListItem ) ); 00968 prvAddTaskToReadyQueue( pxTCB ); 00969 00970 /* We may have just resumed a higher priority task. */ 00971 if( pxTCB->uxPriority >= pxCurrentTCB->uxPriority ) 00972 { 00973 /* This yield may not cause the task just resumed to run, but 00974 will leave the lists in the correct state for the next yield. */ 00975 portYIELD_WITHIN_API(); 00976 } 00977 } 00978 } 00979 portEXIT_CRITICAL(); 00980 } 00981 } 00982 00983 #endif 00984 00985 /*-----------------------------------------------------------*/ 00986 00987 #if ( ( INCLUDE_xTaskResumeFromISR == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) ) 00988 00989 portBASE_TYPE xTaskResumeFromISR( xTaskHandle pxTaskToResume ) 00990 { 00991 portBASE_TYPE xYieldRequired = pdFALSE; 00992 tskTCB *pxTCB; 00993 00994 pxTCB = ( tskTCB * ) pxTaskToResume; 00995 00996 if( xTaskIsTaskSuspended( pxTCB ) == pdTRUE ) 00997 { 00998 traceTASK_RESUME_FROM_ISR( pxTCB ); 00999 01000 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE ) 01001 { 01002 xYieldRequired = ( pxTCB->uxPriority >= pxCurrentTCB->uxPriority ); 01003 vListRemove( &( pxTCB->xGenericListItem ) ); 01004 prvAddTaskToReadyQueue( pxTCB ); 01005 } 01006 else 01007 { 01008 /* We cannot access the delayed or ready lists, so will hold this 01009 task pending until the scheduler is resumed, at which point a 01010 yield will be performed if necessary. */ 01011 vListInsertEnd( ( xList * ) &( xPendingReadyList ), &( pxTCB->xEventListItem ) ); 01012 } 01013 } 01014 01015 return xYieldRequired; 01016 } 01017 01018 #endif 01019 01020 01021 01022 01023 /*----------------------------------------------------------- 01024 * PUBLIC SCHEDULER CONTROL documented in task.h 01025 *----------------------------------------------------------*/ 01026 01027 // Modified by Kenji Arai / JH1PJL, October 30th,2010 01028 // move to port_asm.c 01029 #if 0 01030 void vTaskStartScheduler( void ) 01031 { 01032 portBASE_TYPE xReturn; 01033 01034 /* Add the idle task at the lowest priority. */ 01035 xReturn = xTaskCreate( prvIdleTask, ( signed char * ) "IDLE", tskIDLE_STACK_SIZE, ( void * ) NULL, ( tskIDLE_PRIORITY | portPRIVILEGE_BIT ), ( xTaskHandle * ) NULL ); 01036 01037 if( xReturn == pdPASS ) 01038 { 01039 /* Interrupts are turned off here, to ensure a tick does not occur 01040 before or during the call to xPortStartScheduler(). The stacks of 01041 the created tasks contain a status word with interrupts switched on 01042 so interrupts will automatically get re-enabled when the first task 01043 starts to run. 01044 01045 STEPPING THROUGH HERE USING A DEBUGGER CAN CAUSE BIG PROBLEMS IF THE 01046 DEBUGGER ALLOWS INTERRUPTS TO BE PROCESSED. */ 01047 portDISABLE_INTERRUPTS(); 01048 01049 xSchedulerRunning = pdTRUE; 01050 xTickCount = ( portTickType ) 0; 01051 01052 /* If configGENERATE_RUN_TIME_STATS is defined then the following 01053 macro must be defined to configure the timer/counter used to generate 01054 the run time counter time base. */ 01055 portCONFIGURE_TIMER_FOR_RUN_TIME_STATS(); 01056 01057 /* Setting up the timer tick is hardware specific and thus in the 01058 portable interface. */ 01059 if( xPortStartScheduler() ) 01060 { 01061 /* Should not reach here as if the scheduler is running the 01062 function will not return. */ 01063 } 01064 else 01065 { 01066 /* Should only reach here if a task calls xTaskEndScheduler(). */ 01067 } 01068 } 01069 } 01070 /*-----------------------------------------------------------*/ 01071 01072 void vTaskEndScheduler( void ) 01073 { 01074 /* Stop the scheduler interrupts and call the portable scheduler end 01075 routine so the original ISRs can be restored if necessary. The port 01076 layer must ensure interrupts enable bit is left in the correct state. */ 01077 portDISABLE_INTERRUPTS(); 01078 xSchedulerRunning = pdFALSE; 01079 vPortEndScheduler(); 01080 } 01081 /*----------------------------------------------------------*/ 01082 #endif 01083 01084 void vTaskSuspendAll( void ) 01085 { 01086 /* A critical section is not required as the variable is of type 01087 portBASE_TYPE. */ 01088 ++uxSchedulerSuspended; 01089 } 01090 /*----------------------------------------------------------*/ 01091 01092 signed portBASE_TYPE xTaskResumeAll( void ) 01093 { 01094 register tskTCB *pxTCB; 01095 signed portBASE_TYPE xAlreadyYielded = pdFALSE; 01096 01097 /* It is possible that an ISR caused a task to be removed from an event 01098 list while the scheduler was suspended. If this was the case then the 01099 removed task will have been added to the xPendingReadyList. Once the 01100 scheduler has been resumed it is safe to move all the pending ready 01101 tasks from this list into their appropriate ready list. */ 01102 portENTER_CRITICAL(); 01103 { 01104 --uxSchedulerSuspended; 01105 01106 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE ) 01107 { 01108 if( uxCurrentNumberOfTasks > ( unsigned portBASE_TYPE ) 0 ) 01109 { 01110 portBASE_TYPE xYieldRequired = pdFALSE; 01111 01112 /* Move any readied tasks from the pending list into the 01113 appropriate ready list. */ 01114 while( ( pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xPendingReadyList ) ) ) != NULL ) 01115 { 01116 vListRemove( &( pxTCB->xEventListItem ) ); 01117 vListRemove( &( pxTCB->xGenericListItem ) ); 01118 prvAddTaskToReadyQueue( pxTCB ); 01119 01120 /* If we have moved a task that has a priority higher than 01121 the current task then we should yield. */ 01122 if( pxTCB->uxPriority >= pxCurrentTCB->uxPriority ) 01123 { 01124 xYieldRequired = pdTRUE; 01125 } 01126 } 01127 01128 /* If any ticks occurred while the scheduler was suspended then 01129 they should be processed now. This ensures the tick count does not 01130 slip, and that any delayed tasks are resumed at the correct time. */ 01131 if( uxMissedTicks > ( unsigned portBASE_TYPE ) 0 ) 01132 { 01133 while( uxMissedTicks > ( unsigned portBASE_TYPE ) 0 ) 01134 { 01135 vTaskIncrementTick(); 01136 --uxMissedTicks; 01137 } 01138 01139 /* As we have processed some ticks it is appropriate to yield 01140 to ensure the highest priority task that is ready to run is 01141 the task actually running. */ 01142 #if configUSE_PREEMPTION == 1 01143 { 01144 xYieldRequired = pdTRUE; 01145 } 01146 #endif 01147 } 01148 01149 if( ( xYieldRequired == pdTRUE ) || ( xMissedYield == pdTRUE ) ) 01150 { 01151 xAlreadyYielded = pdTRUE; 01152 xMissedYield = pdFALSE; 01153 portYIELD_WITHIN_API(); 01154 } 01155 } 01156 } 01157 } 01158 portEXIT_CRITICAL(); 01159 01160 return xAlreadyYielded; 01161 } 01162 01163 01164 01165 01166 01167 01168 /*----------------------------------------------------------- 01169 * PUBLIC TASK UTILITIES documented in task.h 01170 *----------------------------------------------------------*/ 01171 01172 01173 01174 portTickType xTaskGetTickCount( void ) 01175 { 01176 portTickType xTicks; 01177 01178 /* Critical section required if running on a 16 bit processor. */ 01179 portENTER_CRITICAL(); 01180 { 01181 xTicks = xTickCount; 01182 } 01183 portEXIT_CRITICAL(); 01184 01185 return xTicks; 01186 } 01187 /*-----------------------------------------------------------*/ 01188 01189 unsigned portBASE_TYPE uxTaskGetNumberOfTasks( void ) 01190 { 01191 /* A critical section is not required because the variables are of type 01192 portBASE_TYPE. */ 01193 return uxCurrentNumberOfTasks; 01194 } 01195 /*-----------------------------------------------------------*/ 01196 01197 #if ( configUSE_TRACE_FACILITY == 1 ) 01198 01199 void vTaskList( signed char *pcWriteBuffer ) 01200 { 01201 unsigned portBASE_TYPE uxQueue; 01202 01203 /* This is a VERY costly function that should be used for debug only. 01204 It leaves interrupts disabled for a LONG time. */ 01205 01206 vTaskSuspendAll(); 01207 { 01208 /* Run through all the lists that could potentially contain a TCB and 01209 report the task name, state and stack high water mark. */ 01210 01211 pcWriteBuffer[ 0 ] = ( signed char ) 0x00; 01212 strcat( ( char * ) pcWriteBuffer, ( const char * ) "\r\n" ); 01213 01214 uxQueue = uxTopUsedPriority + 1; 01215 01216 do 01217 { 01218 uxQueue--; 01219 01220 if( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxQueue ] ) ) ) 01221 { 01222 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &( pxReadyTasksLists[ uxQueue ] ), tskREADY_CHAR ); 01223 } 01224 }while( uxQueue > ( unsigned short ) tskIDLE_PRIORITY ); 01225 01226 if( !listLIST_IS_EMPTY( pxDelayedTaskList ) ) 01227 { 01228 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) pxDelayedTaskList, tskBLOCKED_CHAR ); 01229 } 01230 01231 if( !listLIST_IS_EMPTY( pxOverflowDelayedTaskList ) ) 01232 { 01233 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) pxOverflowDelayedTaskList, tskBLOCKED_CHAR ); 01234 } 01235 01236 #if( INCLUDE_vTaskDelete == 1 ) 01237 { 01238 if( !listLIST_IS_EMPTY( &xTasksWaitingTermination ) ) 01239 { 01240 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &xTasksWaitingTermination, tskDELETED_CHAR ); 01241 } 01242 } 01243 #endif 01244 01245 #if ( INCLUDE_vTaskSuspend == 1 ) 01246 { 01247 if( !listLIST_IS_EMPTY( &xSuspendedTaskList ) ) 01248 { 01249 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &xSuspendedTaskList, tskSUSPENDED_CHAR ); 01250 } 01251 } 01252 #endif 01253 } 01254 xTaskResumeAll(); 01255 } 01256 01257 #endif 01258 /*----------------------------------------------------------*/ 01259 01260 #if ( configGENERATE_RUN_TIME_STATS == 1 ) 01261 01262 void vTaskGetRunTimeStats( signed char *pcWriteBuffer ) 01263 { 01264 unsigned portBASE_TYPE uxQueue; 01265 unsigned long ulTotalRunTime = portGET_RUN_TIME_COUNTER_VALUE(); 01266 01267 /* This is a VERY costly function that should be used for debug only. 01268 It leaves interrupts disabled for a LONG time. */ 01269 01270 vTaskSuspendAll(); 01271 { 01272 /* Run through all the lists that could potentially contain a TCB, 01273 generating a table of run timer percentages in the provided 01274 buffer. */ 01275 01276 pcWriteBuffer[ 0 ] = ( signed char ) 0x00; 01277 strcat( ( char * ) pcWriteBuffer, ( const char * ) "\r\n" ); 01278 01279 uxQueue = uxTopUsedPriority + 1; 01280 01281 do 01282 { 01283 uxQueue--; 01284 01285 if( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxQueue ] ) ) ) 01286 { 01287 prvGenerateRunTimeStatsForTasksInList( pcWriteBuffer, ( xList * ) &( pxReadyTasksLists[ uxQueue ] ), ulTotalRunTime ); 01288 } 01289 }while( uxQueue > ( unsigned short ) tskIDLE_PRIORITY ); 01290 01291 if( !listLIST_IS_EMPTY( pxDelayedTaskList ) ) 01292 { 01293 prvGenerateRunTimeStatsForTasksInList( pcWriteBuffer, ( xList * ) pxDelayedTaskList, ulTotalRunTime ); 01294 } 01295 01296 if( !listLIST_IS_EMPTY( pxOverflowDelayedTaskList ) ) 01297 { 01298 prvGenerateRunTimeStatsForTasksInList( pcWriteBuffer, ( xList * ) pxOverflowDelayedTaskList, ulTotalRunTime ); 01299 } 01300 01301 #if ( INCLUDE_vTaskDelete == 1 ) 01302 { 01303 if( !listLIST_IS_EMPTY( &xTasksWaitingTermination ) ) 01304 { 01305 prvGenerateRunTimeStatsForTasksInList( pcWriteBuffer, ( xList * ) &xTasksWaitingTermination, ulTotalRunTime ); 01306 } 01307 } 01308 #endif 01309 01310 #if ( INCLUDE_vTaskSuspend == 1 ) 01311 { 01312 if( !listLIST_IS_EMPTY( &xSuspendedTaskList ) ) 01313 { 01314 prvGenerateRunTimeStatsForTasksInList( pcWriteBuffer, ( xList * ) &xSuspendedTaskList, ulTotalRunTime ); 01315 } 01316 } 01317 #endif 01318 } 01319 xTaskResumeAll(); 01320 } 01321 01322 #endif 01323 /*----------------------------------------------------------*/ 01324 01325 #if ( configUSE_TRACE_FACILITY == 1 ) 01326 01327 void vTaskStartTrace( signed char * pcBuffer, unsigned long ulBufferSize ) 01328 { 01329 portENTER_CRITICAL(); 01330 { 01331 pcTraceBuffer = ( signed char * )pcBuffer; 01332 pcTraceBufferStart = pcBuffer; 01333 pcTraceBufferEnd = pcBuffer + ( ulBufferSize - tskSIZE_OF_EACH_TRACE_LINE ); 01334 xTracing = pdTRUE; 01335 } 01336 portEXIT_CRITICAL(); 01337 } 01338 01339 #endif 01340 /*----------------------------------------------------------*/ 01341 01342 #if ( configUSE_TRACE_FACILITY == 1 ) 01343 01344 unsigned long ulTaskEndTrace( void ) 01345 { 01346 unsigned long ulBufferLength; 01347 01348 portENTER_CRITICAL(); 01349 xTracing = pdFALSE; 01350 portEXIT_CRITICAL(); 01351 01352 ulBufferLength = ( unsigned long ) ( pcTraceBuffer - pcTraceBufferStart ); 01353 01354 return ulBufferLength; 01355 } 01356 01357 #endif 01358 01359 01360 01361 /*----------------------------------------------------------- 01362 * SCHEDULER INTERNALS AVAILABLE FOR PORTING PURPOSES 01363 * documented in task.h 01364 *----------------------------------------------------------*/ 01365 01366 01367 void vTaskIncrementTick( void ) 01368 { 01369 /* Called by the portable layer each time a tick interrupt occurs. 01370 Increments the tick then checks to see if the new tick value will cause any 01371 tasks to be unblocked. */ 01372 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE ) 01373 { 01374 ++xTickCount; 01375 if( xTickCount == ( portTickType ) 0 ) 01376 { 01377 xList *pxTemp; 01378 01379 /* Tick count has overflowed so we need to swap the delay lists. 01380 If there are any items in pxDelayedTaskList here then there is 01381 an error! */ 01382 pxTemp = pxDelayedTaskList; 01383 pxDelayedTaskList = pxOverflowDelayedTaskList; 01384 pxOverflowDelayedTaskList = pxTemp; 01385 xNumOfOverflows++; 01386 } 01387 01388 /* See if this tick has made a timeout expire. */ 01389 prvCheckDelayedTasks(); 01390 } 01391 else 01392 { 01393 ++uxMissedTicks; 01394 01395 /* The tick hook gets called at regular intervals, even if the 01396 scheduler is locked. */ 01397 #if ( configUSE_TICK_HOOK == 1 ) 01398 { 01399 // extern void vApplicationTickHook( void ); 01400 01401 vApplicationTickHook(); 01402 } 01403 #endif 01404 } 01405 01406 #if ( configUSE_TICK_HOOK == 1 ) 01407 { 01408 extern void vApplicationTickHook( void ); 01409 01410 /* Guard against the tick hook being called when the missed tick 01411 count is being unwound (when the scheduler is being unlocked. */ 01412 if( uxMissedTicks == 0 ) 01413 { 01414 vApplicationTickHook(); 01415 } 01416 } 01417 #endif 01418 01419 traceTASK_INCREMENT_TICK( xTickCount ); 01420 } 01421 /*-----------------------------------------------------------*/ 01422 01423 #if ( ( INCLUDE_vTaskCleanUpResources == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) ) 01424 01425 void vTaskCleanUpResources( void ) 01426 { 01427 unsigned short usQueue; 01428 volatile tskTCB *pxTCB; 01429 01430 usQueue = ( unsigned short ) uxTopUsedPriority + ( unsigned short ) 1; 01431 01432 /* Remove any TCB's from the ready queues. */ 01433 do 01434 { 01435 usQueue--; 01436 01437 while( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ usQueue ] ) ) ) 01438 { 01439 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &( pxReadyTasksLists[ usQueue ] ) ); 01440 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) ); 01441 01442 prvDeleteTCB( ( tskTCB * ) pxTCB ); 01443 } 01444 }while( usQueue > ( unsigned short ) tskIDLE_PRIORITY ); 01445 01446 /* Remove any TCB's from the delayed queue. */ 01447 while( !listLIST_IS_EMPTY( &xDelayedTaskList1 ) ) 01448 { 01449 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xDelayedTaskList1 ); 01450 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) ); 01451 01452 prvDeleteTCB( ( tskTCB * ) pxTCB ); 01453 } 01454 01455 /* Remove any TCB's from the overflow delayed queue. */ 01456 while( !listLIST_IS_EMPTY( &xDelayedTaskList2 ) ) 01457 { 01458 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xDelayedTaskList2 ); 01459 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) ); 01460 01461 prvDeleteTCB( ( tskTCB * ) pxTCB ); 01462 } 01463 01464 while( !listLIST_IS_EMPTY( &xSuspendedTaskList ) ) 01465 { 01466 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xSuspendedTaskList ); 01467 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) ); 01468 01469 prvDeleteTCB( ( tskTCB * ) pxTCB ); 01470 } 01471 } 01472 01473 #endif 01474 /*-----------------------------------------------------------*/ 01475 01476 #if ( configUSE_APPLICATION_TASK_TAG == 1 ) 01477 01478 void vTaskSetApplicationTaskTag( xTaskHandle xTask, pdTASK_HOOK_CODE pxTagValue ) 01479 { 01480 tskTCB *xTCB; 01481 01482 /* If xTask is NULL then we are setting our own task hook. */ 01483 if( xTask == NULL ) 01484 { 01485 xTCB = ( tskTCB * ) pxCurrentTCB; 01486 } 01487 else 01488 { 01489 xTCB = ( tskTCB * ) xTask; 01490 } 01491 01492 /* Save the hook function in the TCB. A critical section is required as 01493 the value can be accessed from an interrupt. */ 01494 portENTER_CRITICAL(); 01495 xTCB->pxTaskTag = pxTagValue; 01496 portEXIT_CRITICAL(); 01497 } 01498 01499 #endif 01500 /*-----------------------------------------------------------*/ 01501 01502 #if ( configUSE_APPLICATION_TASK_TAG == 1 ) 01503 01504 pdTASK_HOOK_CODE xTaskGetApplicationTaskTag( xTaskHandle xTask ) 01505 { 01506 tskTCB *xTCB; 01507 pdTASK_HOOK_CODE xReturn; 01508 01509 /* If xTask is NULL then we are setting our own task hook. */ 01510 if( xTask == NULL ) 01511 { 01512 xTCB = ( tskTCB * ) pxCurrentTCB; 01513 } 01514 else 01515 { 01516 xTCB = ( tskTCB * ) xTask; 01517 } 01518 01519 /* Save the hook function in the TCB. A critical section is required as 01520 the value can be accessed from an interrupt. */ 01521 portENTER_CRITICAL(); 01522 xReturn = xTCB->pxTaskTag; 01523 portEXIT_CRITICAL(); 01524 01525 return xReturn; 01526 } 01527 01528 #endif 01529 /*-----------------------------------------------------------*/ 01530 01531 #if ( configUSE_APPLICATION_TASK_TAG == 1 ) 01532 01533 portBASE_TYPE xTaskCallApplicationTaskHook( xTaskHandle xTask, void *pvParameter ) 01534 { 01535 tskTCB *xTCB; 01536 portBASE_TYPE xReturn; 01537 01538 /* If xTask is NULL then we are calling our own task hook. */ 01539 if( xTask == NULL ) 01540 { 01541 xTCB = ( tskTCB * ) pxCurrentTCB; 01542 } 01543 else 01544 { 01545 xTCB = ( tskTCB * ) xTask; 01546 } 01547 01548 if( xTCB->pxTaskTag != NULL ) 01549 { 01550 xReturn = xTCB->pxTaskTag( pvParameter ); 01551 } 01552 else 01553 { 01554 xReturn = pdFAIL; 01555 } 01556 01557 return xReturn; 01558 } 01559 01560 #endif 01561 /*-----------------------------------------------------------*/ 01562 01563 void vTaskSwitchContext( void ) 01564 { 01565 if( uxSchedulerSuspended != ( unsigned portBASE_TYPE ) pdFALSE ) 01566 { 01567 /* The scheduler is currently suspended - do not allow a context 01568 switch. */ 01569 xMissedYield = pdTRUE; 01570 return; 01571 } 01572 01573 traceTASK_SWITCHED_OUT(); 01574 01575 #if ( configGENERATE_RUN_TIME_STATS == 1 ) 01576 { 01577 unsigned long ulTempCounter = portGET_RUN_TIME_COUNTER_VALUE(); 01578 01579 /* Add the amount of time the task has been running to the accumulated 01580 time so far. The time the task started running was stored in 01581 ulTaskSwitchedInTime. Note that there is no overflow protection here 01582 so count values are only valid until the timer overflows. Generally 01583 this will be about 1 hour assuming a 1uS timer increment. */ 01584 pxCurrentTCB->ulRunTimeCounter += ( ulTempCounter - ulTaskSwitchedInTime ); 01585 ulTaskSwitchedInTime = ulTempCounter; 01586 } 01587 #endif 01588 01589 taskFIRST_CHECK_FOR_STACK_OVERFLOW(); 01590 taskSECOND_CHECK_FOR_STACK_OVERFLOW(); 01591 01592 /* Find the highest priority queue that contains ready tasks. */ 01593 while( listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxTopReadyPriority ] ) ) ) 01594 { 01595 --uxTopReadyPriority; 01596 } 01597 01598 /* listGET_OWNER_OF_NEXT_ENTRY walks through the list, so the tasks of the 01599 same priority get an equal share of the processor time. */ 01600 listGET_OWNER_OF_NEXT_ENTRY( pxCurrentTCB, &( pxReadyTasksLists[ uxTopReadyPriority ] ) ); 01601 #if 0 01602 //#define listGET_OWNER_OF_NEXT_ENTRY( pxTCB, pxList ) 01603 { 01604 xList * const pxConstList = &( pxReadyTasksLists[ uxTopReadyPriority ] ); 01605 /* Increment the index to the next item and return the item, ensuring */ 01606 /* we don't return the marker used at the end of the list. */ 01607 ( pxConstList )->pxIndex = ( pxConstList )->pxIndex->pxNext; 01608 if( ( pxConstList )->pxIndex == ( xListItem * ) &( ( pxConstList )->xListEnd ) ) 01609 { 01610 ( pxConstList )->pxIndex = ( pxConstList )->pxIndex->pxNext; 01611 } 01612 pxCurrentTCB = (tskTCB *) (( pxConstList )->pxIndex->pvOwner); // Error then added (tskTCB *)() 01613 } 01614 #endif 01615 01616 traceTASK_SWITCHED_IN(); 01617 vWriteTraceToBuffer(); 01618 } 01619 /*-----------------------------------------------------------*/ 01620 01621 void vTaskPlaceOnEventList( const xList * const pxEventList, portTickType xTicksToWait ) 01622 { 01623 portTickType xTimeToWake; 01624 01625 /* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE 01626 SCHEDULER SUSPENDED. */ 01627 01628 /* Place the event list item of the TCB in the appropriate event list. 01629 This is placed in the list in priority order so the highest priority task 01630 is the first to be woken by the event. */ 01631 vListInsert( ( xList * ) pxEventList, ( xListItem * ) &( pxCurrentTCB->xEventListItem ) ); 01632 01633 /* We must remove ourselves from the ready list before adding ourselves 01634 to the blocked list as the same list item is used for both lists. We have 01635 exclusive access to the ready lists as the scheduler is locked. */ 01636 vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 01637 01638 01639 #if ( INCLUDE_vTaskSuspend == 1 ) 01640 { 01641 if( xTicksToWait == portMAX_DELAY ) 01642 { 01643 /* Add ourselves to the suspended task list instead of a delayed task 01644 list to ensure we are not woken by a timing event. We will block 01645 indefinitely. */ 01646 vListInsertEnd( ( xList * ) &xSuspendedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 01647 } 01648 else 01649 { 01650 /* Calculate the time at which the task should be woken if the event does 01651 not occur. This may overflow but this doesn't matter. */ 01652 xTimeToWake = xTickCount + xTicksToWait; 01653 01654 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake ); 01655 01656 if( xTimeToWake < xTickCount ) 01657 { 01658 /* Wake time has overflowed. Place this item in the overflow list. */ 01659 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 01660 } 01661 else 01662 { 01663 /* The wake time has not overflowed, so we can use the current block list. */ 01664 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 01665 } 01666 } 01667 } 01668 #else 01669 { 01670 /* Calculate the time at which the task should be woken if the event does 01671 not occur. This may overflow but this doesn't matter. */ 01672 xTimeToWake = xTickCount + xTicksToWait; 01673 01674 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake ); 01675 01676 if( xTimeToWake < xTickCount ) 01677 { 01678 /* Wake time has overflowed. Place this item in the overflow list. */ 01679 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 01680 } 01681 else 01682 { 01683 /* The wake time has not overflowed, so we can use the current block list. */ 01684 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) ); 01685 } 01686 } 01687 #endif 01688 } 01689 /*-----------------------------------------------------------*/ 01690 01691 signed portBASE_TYPE xTaskRemoveFromEventList( const xList * const pxEventList ) 01692 { 01693 tskTCB *pxUnblockedTCB; 01694 portBASE_TYPE xReturn; 01695 01696 /* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE 01697 SCHEDULER SUSPENDED. It can also be called from within an ISR. */ 01698 01699 /* The event list is sorted in priority order, so we can remove the 01700 first in the list, remove the TCB from the delayed list, and add 01701 it to the ready list. 01702 01703 If an event is for a queue that is locked then this function will never 01704 get called - the lock count on the queue will get modified instead. This 01705 means we can always expect exclusive access to the event list here. */ 01706 pxUnblockedTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxEventList ); 01707 vListRemove( &( pxUnblockedTCB->xEventListItem ) ); 01708 01709 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE ) 01710 { 01711 vListRemove( &( pxUnblockedTCB->xGenericListItem ) ); 01712 prvAddTaskToReadyQueue( pxUnblockedTCB ); 01713 } 01714 else 01715 { 01716 /* We cannot access the delayed or ready lists, so will hold this 01717 task pending until the scheduler is resumed. */ 01718 vListInsertEnd( ( xList * ) &( xPendingReadyList ), &( pxUnblockedTCB->xEventListItem ) ); 01719 } 01720 01721 if( pxUnblockedTCB->uxPriority >= pxCurrentTCB->uxPriority ) 01722 { 01723 /* Return true if the task removed from the event list has 01724 a higher priority than the calling task. This allows 01725 the calling task to know if it should force a context 01726 switch now. */ 01727 xReturn = pdTRUE; 01728 } 01729 else 01730 { 01731 xReturn = pdFALSE; 01732 } 01733 01734 return xReturn; 01735 } 01736 /*-----------------------------------------------------------*/ 01737 01738 void vTaskSetTimeOutState( xTimeOutType * const pxTimeOut ) 01739 { 01740 pxTimeOut->xOverflowCount = xNumOfOverflows; 01741 pxTimeOut->xTimeOnEntering = xTickCount; 01742 } 01743 /*-----------------------------------------------------------*/ 01744 01745 portBASE_TYPE xTaskCheckForTimeOut( xTimeOutType * const pxTimeOut, portTickType * const pxTicksToWait ) 01746 { 01747 portBASE_TYPE xReturn; 01748 01749 portENTER_CRITICAL(); 01750 { 01751 #if ( INCLUDE_vTaskSuspend == 1 ) 01752 /* If INCLUDE_vTaskSuspend is set to 1 and the block time specified is 01753 the maximum block time then the task should block indefinitely, and 01754 therefore never time out. */ 01755 if( *pxTicksToWait == portMAX_DELAY ) 01756 { 01757 xReturn = pdFALSE; 01758 } 01759 else /* We are not blocking indefinitely, perform the checks below. */ 01760 #endif 01761 01762 if( ( xNumOfOverflows != pxTimeOut->xOverflowCount ) && ( ( portTickType ) xTickCount >= ( portTickType ) pxTimeOut->xTimeOnEntering ) ) 01763 { 01764 /* The tick count is greater than the time at which vTaskSetTimeout() 01765 was called, but has also overflowed since vTaskSetTimeOut() was called. 01766 It must have wrapped all the way around and gone past us again. This 01767 passed since vTaskSetTimeout() was called. */ 01768 xReturn = pdTRUE; 01769 } 01770 else if( ( ( portTickType ) ( ( portTickType ) xTickCount - ( portTickType ) pxTimeOut->xTimeOnEntering ) ) < ( portTickType ) *pxTicksToWait ) 01771 { 01772 /* Not a genuine timeout. Adjust parameters for time remaining. */ 01773 *pxTicksToWait -= ( ( portTickType ) xTickCount - ( portTickType ) pxTimeOut->xTimeOnEntering ); 01774 vTaskSetTimeOutState( pxTimeOut ); 01775 xReturn = pdFALSE; 01776 } 01777 else 01778 { 01779 xReturn = pdTRUE; 01780 } 01781 } 01782 portEXIT_CRITICAL(); 01783 01784 return xReturn; 01785 } 01786 /*-----------------------------------------------------------*/ 01787 01788 void vTaskMissedYield( void ) 01789 { 01790 xMissedYield = pdTRUE; 01791 } 01792 01793 /* 01794 * ----------------------------------------------------------- 01795 * The Idle task. 01796 * ---------------------------------------------------------- 01797 * 01798 * The portTASK_FUNCTION() macro is used to allow port/compiler specific 01799 * language extensions. The equivalent prototype for this function is: 01800 * 01801 * void prvIdleTask( void *pvParameters ); 01802 * 01803 */ 01804 static portTASK_FUNCTION( prvIdleTask, pvParameters ) 01805 { 01806 /* Stop warnings. */ 01807 ( void ) pvParameters; 01808 01809 for( ;; ) 01810 { 01811 /* See if any tasks have been deleted. */ 01812 prvCheckTasksWaitingTermination(); 01813 01814 #if ( configUSE_PREEMPTION == 0 ) 01815 { 01816 /* If we are not using preemption we keep forcing a task switch to 01817 see if any other task has become available. If we are using 01818 preemption we don't need to do this as any task becoming available 01819 will automatically get the processor anyway. */ 01820 taskYIELD(); 01821 } 01822 #endif 01823 01824 #if ( ( configUSE_PREEMPTION == 1 ) && ( configIDLE_SHOULD_YIELD == 1 ) ) 01825 { 01826 /* When using preemption tasks of equal priority will be 01827 timesliced. If a task that is sharing the idle priority is ready 01828 to run then the idle task should yield before the end of the 01829 timeslice. 01830 01831 A critical region is not required here as we are just reading from 01832 the list, and an occasional incorrect value will not matter. If 01833 the ready list at the idle priority contains more than one task 01834 then a task other than the idle task is ready to execute. */ 01835 if( listCURRENT_LIST_LENGTH( &( pxReadyTasksLists[ tskIDLE_PRIORITY ] ) ) > ( unsigned portBASE_TYPE ) 1 ) 01836 { 01837 taskYIELD(); 01838 } 01839 } 01840 #endif 01841 01842 #if ( configUSE_IDLE_HOOK == 1 ) 01843 { 01844 extern void vApplicationIdleHook( void ); 01845 01846 /* Call the user defined function from within the idle task. This 01847 allows the application designer to add background functionality 01848 without the overhead of a separate task. 01849 NOTE: vApplicationIdleHook() MUST NOT, UNDER ANY CIRCUMSTANCES, 01850 CALL A FUNCTION THAT MIGHT BLOCK. */ 01851 vApplicationIdleHook(); 01852 } 01853 #endif 01854 } 01855 } /*lint !e715 pvParameters is not accessed but all task functions require the same prototype. */ 01856 01857 01858 01859 01860 01861 01862 01863 /*----------------------------------------------------------- 01864 * File private functions documented at the top of the file. 01865 *----------------------------------------------------------*/ 01866 01867 01868 01869 static void prvInitialiseTCBVariables( tskTCB *pxTCB, const signed char * const pcName, unsigned portBASE_TYPE uxPriority, const xMemoryRegion * const xRegions, unsigned short usStackDepth ) 01870 { 01871 /* Store the function name in the TCB. */ 01872 #if configMAX_TASK_NAME_LEN > 1 01873 { 01874 /* Don't bring strncpy into the build unnecessarily. */ 01875 strncpy( ( char * ) pxTCB->pcTaskName, ( const char * ) pcName, ( unsigned short ) configMAX_TASK_NAME_LEN ); 01876 } 01877 #endif 01878 pxTCB->pcTaskName[ ( unsigned short ) configMAX_TASK_NAME_LEN - ( unsigned short ) 1 ] = '\0'; 01879 01880 /* This is used as an array index so must ensure it's not too large. First 01881 remove the privilege bit if one is present. */ 01882 if( uxPriority >= configMAX_PRIORITIES ) 01883 { 01884 uxPriority = configMAX_PRIORITIES - 1; 01885 } 01886 01887 pxTCB->uxPriority = uxPriority; 01888 #if ( configUSE_MUTEXES == 1 ) 01889 { 01890 pxTCB->uxBasePriority = uxPriority; 01891 } 01892 #endif 01893 01894 vListInitialiseItem( &( pxTCB->xGenericListItem ) ); 01895 vListInitialiseItem( &( pxTCB->xEventListItem ) ); 01896 01897 /* Set the pxTCB as a link back from the xListItem. This is so we can get 01898 back to the containing TCB from a generic item in a list. */ 01899 listSET_LIST_ITEM_OWNER( &( pxTCB->xGenericListItem ), pxTCB ); 01900 01901 /* Event lists are always in priority order. */ 01902 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) uxPriority ); 01903 listSET_LIST_ITEM_OWNER( &( pxTCB->xEventListItem ), pxTCB ); 01904 01905 #if ( portCRITICAL_NESTING_IN_TCB == 1 ) 01906 { 01907 pxTCB->uxCriticalNesting = ( unsigned portBASE_TYPE ) 0; 01908 } 01909 #endif 01910 01911 #if ( configUSE_APPLICATION_TASK_TAG == 1 ) 01912 { 01913 pxTCB->pxTaskTag = NULL; 01914 } 01915 #endif 01916 01917 #if ( configGENERATE_RUN_TIME_STATS == 1 ) 01918 { 01919 pxTCB->ulRunTimeCounter = 0UL; 01920 } 01921 #endif 01922 01923 #if ( portUSING_MPU_WRAPPERS == 1 ) 01924 { 01925 vPortStoreTaskMPUSettings( &( pxTCB->xMPUSettings ), xRegions, pxTCB->pxStack, usStackDepth ); 01926 } 01927 #else 01928 { 01929 ( void ) xRegions; 01930 ( void ) usStackDepth; 01931 } 01932 #endif 01933 } 01934 /*-----------------------------------------------------------*/ 01935 01936 #if ( portUSING_MPU_WRAPPERS == 1 ) 01937 01938 void vTaskAllocateMPURegions( xTaskHandle xTaskToModify, const xMemoryRegion * const xRegions ) 01939 { 01940 tskTCB *pxTCB; 01941 01942 if( xTaskToModify == pxCurrentTCB ) 01943 { 01944 xTaskToModify = NULL; 01945 } 01946 01947 /* If null is passed in here then we are deleting ourselves. */ 01948 pxTCB = prvGetTCBFromHandle( xTaskToModify ); 01949 01950 vPortStoreTaskMPUSettings( &( pxTCB->xMPUSettings ), xRegions, NULL, 0 ); 01951 } 01952 /*-----------------------------------------------------------*/ 01953 #endif 01954 01955 static void prvInitialiseTaskLists( void ) 01956 { 01957 unsigned portBASE_TYPE uxPriority; 01958 01959 for( uxPriority = 0; uxPriority < configMAX_PRIORITIES; uxPriority++ ) 01960 { 01961 vListInitialise( ( xList * ) &( pxReadyTasksLists[ uxPriority ] ) ); 01962 } 01963 01964 vListInitialise( ( xList * ) &xDelayedTaskList1 ); 01965 vListInitialise( ( xList * ) &xDelayedTaskList2 ); 01966 vListInitialise( ( xList * ) &xPendingReadyList ); 01967 01968 #if ( INCLUDE_vTaskDelete == 1 ) 01969 { 01970 vListInitialise( ( xList * ) &xTasksWaitingTermination ); 01971 } 01972 #endif 01973 01974 #if ( INCLUDE_vTaskSuspend == 1 ) 01975 { 01976 vListInitialise( ( xList * ) &xSuspendedTaskList ); 01977 } 01978 #endif 01979 01980 /* Start with pxDelayedTaskList using list1 and the pxOverflowDelayedTaskList 01981 using list2. */ 01982 pxDelayedTaskList = &xDelayedTaskList1; 01983 pxOverflowDelayedTaskList = &xDelayedTaskList2; 01984 } 01985 /*-----------------------------------------------------------*/ 01986 01987 static void prvCheckTasksWaitingTermination( void ) 01988 { 01989 #if ( INCLUDE_vTaskDelete == 1 ) 01990 { 01991 portBASE_TYPE xListIsEmpty; 01992 01993 /* ucTasksDeleted is used to prevent vTaskSuspendAll() being called 01994 too often in the idle task. */ 01995 if( uxTasksDeleted > ( unsigned portBASE_TYPE ) 0 ) 01996 { 01997 vTaskSuspendAll(); 01998 xListIsEmpty = listLIST_IS_EMPTY( &xTasksWaitingTermination ); 01999 xTaskResumeAll(); 02000 02001 if( !xListIsEmpty ) 02002 { 02003 tskTCB *pxTCB; 02004 02005 portENTER_CRITICAL(); 02006 { 02007 pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xTasksWaitingTermination ) ); 02008 vListRemove( &( pxTCB->xGenericListItem ) ); 02009 --uxCurrentNumberOfTasks; 02010 --uxTasksDeleted; 02011 } 02012 portEXIT_CRITICAL(); 02013 02014 prvDeleteTCB( pxTCB ); 02015 } 02016 } 02017 } 02018 #endif 02019 } 02020 /*-----------------------------------------------------------*/ 02021 02022 static tskTCB *prvAllocateTCBAndStack( unsigned short usStackDepth, portSTACK_TYPE *puxStackBuffer ) 02023 { 02024 tskTCB *pxNewTCB; 02025 02026 /* Allocate space for the TCB. Where the memory comes from depends on 02027 the implementation of the port malloc function. */ 02028 pxNewTCB = ( tskTCB * ) pvPortMalloc( sizeof( tskTCB ) ); 02029 02030 if( pxNewTCB != NULL ) 02031 { 02032 /* Allocate space for the stack used by the task being created. 02033 The base of the stack memory stored in the TCB so the task can 02034 be deleted later if required. */ 02035 pxNewTCB->pxStack = ( portSTACK_TYPE * ) pvPortMallocAligned( ( ( ( size_t )usStackDepth ) * sizeof( portSTACK_TYPE ) ), puxStackBuffer ); 02036 02037 if( pxNewTCB->pxStack == NULL ) 02038 { 02039 /* Could not allocate the stack. Delete the allocated TCB. */ 02040 vPortFree( pxNewTCB ); 02041 pxNewTCB = NULL; 02042 } 02043 else 02044 { 02045 /* Just to help debugging. */ 02046 memset( pxNewTCB->pxStack, tskSTACK_FILL_BYTE, usStackDepth * sizeof( portSTACK_TYPE ) ); 02047 } 02048 } 02049 02050 return pxNewTCB; 02051 } 02052 /*-----------------------------------------------------------*/ 02053 02054 #if ( configUSE_TRACE_FACILITY == 1 ) 02055 02056 static void prvListTaskWithinSingleList( const signed char *pcWriteBuffer, xList *pxList, signed char cStatus ) 02057 { 02058 volatile tskTCB *pxNextTCB, *pxFirstTCB; 02059 unsigned short usStackRemaining; 02060 02061 /* Write the details of all the TCB's in pxList into the buffer. */ 02062 listGET_OWNER_OF_NEXT_ENTRY( pxFirstTCB, pxList ); 02063 do 02064 { 02065 listGET_OWNER_OF_NEXT_ENTRY( pxNextTCB, pxList ); 02066 #if ( portSTACK_GROWTH > 0 ) 02067 { 02068 usStackRemaining = usTaskCheckFreeStackSpace( ( unsigned char * ) pxNextTCB->pxEndOfStack ); 02069 } 02070 #else 02071 { 02072 usStackRemaining = usTaskCheckFreeStackSpace( ( unsigned char * ) pxNextTCB->pxStack ); 02073 } 02074 #endif 02075 02076 sprintf( pcStatusString, ( char * ) "%s\t\t%c\t%u\t%u\t%u\r\n", pxNextTCB->pcTaskName, cStatus, ( unsigned int ) pxNextTCB->uxPriority, usStackRemaining, ( unsigned int ) pxNextTCB->uxTCBNumber ); 02077 strcat( ( char * ) pcWriteBuffer, ( char * ) pcStatusString ); 02078 02079 } while( pxNextTCB != pxFirstTCB ); 02080 } 02081 02082 #endif 02083 /*-----------------------------------------------------------*/ 02084 02085 #if ( configGENERATE_RUN_TIME_STATS == 1 ) 02086 02087 static void prvGenerateRunTimeStatsForTasksInList( const signed char *pcWriteBuffer, xList *pxList, unsigned long ulTotalRunTime ) 02088 { 02089 volatile tskTCB *pxNextTCB, *pxFirstTCB; 02090 unsigned long ulStatsAsPercentage; 02091 02092 /* Write the run time stats of all the TCB's in pxList into the buffer. */ 02093 listGET_OWNER_OF_NEXT_ENTRY( pxFirstTCB, pxList ); 02094 do 02095 { 02096 /* Get next TCB in from the list. */ 02097 listGET_OWNER_OF_NEXT_ENTRY( pxNextTCB, pxList ); 02098 02099 /* Divide by zero check. */ 02100 if( ulTotalRunTime > 0UL ) 02101 { 02102 /* Has the task run at all? */ 02103 if( pxNextTCB->ulRunTimeCounter == 0 ) 02104 { 02105 /* The task has used no CPU time at all. */ 02106 sprintf( pcStatsString, ( char * ) "%s\t\t0\t\t0%%\r\n", pxNextTCB->pcTaskName ); 02107 } 02108 else 02109 { 02110 /* What percentage of the total run time as the task used? 02111 This will always be rounded down to the nearest integer. */ 02112 ulStatsAsPercentage = ( 100UL * pxNextTCB->ulRunTimeCounter ) / ulTotalRunTime; 02113 02114 if( ulStatsAsPercentage > 0UL ) 02115 { 02116 sprintf( pcStatsString, ( char * ) "%s\t\t%u\t\t%u%%\r\n", pxNextTCB->pcTaskName, ( unsigned int ) pxNextTCB->ulRunTimeCounter, ( unsigned int ) ulStatsAsPercentage ); 02117 } 02118 else 02119 { 02120 /* If the percentage is zero here then the task has 02121 consumed less than 1% of the total run time. */ 02122 sprintf( pcStatsString, ( char * ) "%s\t\t%u\t\t<1%%\r\n", pxNextTCB->pcTaskName, ( unsigned int ) pxNextTCB->ulRunTimeCounter ); 02123 } 02124 } 02125 02126 strcat( ( char * ) pcWriteBuffer, ( char * ) pcStatsString ); 02127 } 02128 02129 } while( pxNextTCB != pxFirstTCB ); 02130 } 02131 02132 #endif 02133 /*-----------------------------------------------------------*/ 02134 02135 #if ( ( configUSE_TRACE_FACILITY == 1 ) || ( INCLUDE_uxTaskGetStackHighWaterMark == 1 ) ) 02136 02137 static unsigned short usTaskCheckFreeStackSpace( const unsigned char * pucStackByte ) 02138 { 02139 register unsigned short usCount = 0; 02140 02141 while( *pucStackByte == tskSTACK_FILL_BYTE ) 02142 { 02143 pucStackByte -= portSTACK_GROWTH; 02144 usCount++; 02145 } 02146 02147 usCount /= sizeof( portSTACK_TYPE ); 02148 02149 return usCount; 02150 } 02151 02152 #endif 02153 /*-----------------------------------------------------------*/ 02154 02155 #if ( INCLUDE_uxTaskGetStackHighWaterMark == 1 ) 02156 02157 unsigned portBASE_TYPE uxTaskGetStackHighWaterMark( xTaskHandle xTask ) 02158 { 02159 tskTCB *pxTCB; 02160 unsigned char *pcEndOfStack; 02161 unsigned portBASE_TYPE uxReturn; 02162 02163 pxTCB = prvGetTCBFromHandle( xTask ); 02164 02165 #if portSTACK_GROWTH < 0 02166 { 02167 pcEndOfStack = ( unsigned char * ) pxTCB->pxStack; 02168 } 02169 #else 02170 { 02171 pcEndOfStack = ( unsigned char * ) pxTCB->pxEndOfStack; 02172 } 02173 #endif 02174 02175 uxReturn = ( unsigned portBASE_TYPE ) usTaskCheckFreeStackSpace( pcEndOfStack ); 02176 02177 return uxReturn; 02178 } 02179 02180 #endif 02181 /*-----------------------------------------------------------*/ 02182 02183 #if ( ( INCLUDE_vTaskDelete == 1 ) || ( INCLUDE_vTaskCleanUpResources == 1 ) ) 02184 02185 static void prvDeleteTCB( tskTCB *pxTCB ) 02186 { 02187 /* Free up the memory allocated by the scheduler for the task. It is up to 02188 the task to free any memory allocated at the application level. */ 02189 vPortFreeAligned( pxTCB->pxStack ); 02190 vPortFree( pxTCB ); 02191 } 02192 02193 #endif 02194 02195 02196 /*-----------------------------------------------------------*/ 02197 02198 #if ( INCLUDE_xTaskGetCurrentTaskHandle == 1 ) 02199 02200 xTaskHandle xTaskGetCurrentTaskHandle( void ) 02201 { 02202 xTaskHandle xReturn; 02203 02204 /* A critical section is not required as this is not called from 02205 an interrupt and the current TCB will always be the same for any 02206 individual execution thread. */ 02207 xReturn = pxCurrentTCB; 02208 02209 return xReturn; 02210 } 02211 02212 #endif 02213 02214 /*-----------------------------------------------------------*/ 02215 02216 #if ( INCLUDE_xTaskGetSchedulerState == 1 ) 02217 02218 portBASE_TYPE xTaskGetSchedulerState( void ) 02219 { 02220 portBASE_TYPE xReturn; 02221 02222 if( xSchedulerRunning == pdFALSE ) 02223 { 02224 xReturn = taskSCHEDULER_NOT_STARTED; 02225 } 02226 else 02227 { 02228 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE ) 02229 { 02230 xReturn = taskSCHEDULER_RUNNING; 02231 } 02232 else 02233 { 02234 xReturn = taskSCHEDULER_SUSPENDED; 02235 } 02236 } 02237 02238 return xReturn; 02239 } 02240 02241 #endif 02242 /*-----------------------------------------------------------*/ 02243 02244 #if ( configUSE_MUTEXES == 1 ) 02245 02246 void vTaskPriorityInherit( xTaskHandle * const pxMutexHolder ) 02247 { 02248 tskTCB * const pxTCB = ( tskTCB * ) pxMutexHolder; 02249 02250 if( pxTCB->uxPriority < pxCurrentTCB->uxPriority ) 02251 { 02252 /* Adjust the mutex holder state to account for its new priority. */ 02253 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) pxCurrentTCB->uxPriority ); 02254 02255 /* If the task being modified is in the ready state it will need to 02256 be moved in to a new list. */ 02257 if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ pxTCB->uxPriority ] ), &( pxTCB->xGenericListItem ) ) ) 02258 { 02259 vListRemove( &( pxTCB->xGenericListItem ) ); 02260 02261 /* Inherit the priority before being moved into the new list. */ 02262 pxTCB->uxPriority = pxCurrentTCB->uxPriority; 02263 prvAddTaskToReadyQueue( pxTCB ); 02264 } 02265 else 02266 { 02267 /* Just inherit the priority. */ 02268 pxTCB->uxPriority = pxCurrentTCB->uxPriority; 02269 } 02270 } 02271 } 02272 02273 #endif 02274 /*-----------------------------------------------------------*/ 02275 02276 #if ( configUSE_MUTEXES == 1 ) 02277 02278 void vTaskPriorityDisinherit( xTaskHandle * const pxMutexHolder ) 02279 { 02280 tskTCB * const pxTCB = ( tskTCB * ) pxMutexHolder; 02281 02282 if( pxMutexHolder != NULL ) 02283 { 02284 if( pxTCB->uxPriority != pxTCB->uxBasePriority ) 02285 { 02286 /* We must be the running task to be able to give the mutex back. 02287 Remove ourselves from the ready list we currently appear in. */ 02288 vListRemove( &( pxTCB->xGenericListItem ) ); 02289 02290 /* Disinherit the priority before adding ourselves into the new 02291 ready list. */ 02292 pxTCB->uxPriority = pxTCB->uxBasePriority; 02293 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) pxTCB->uxPriority ); 02294 prvAddTaskToReadyQueue( pxTCB ); 02295 } 02296 } 02297 } 02298 02299 #endif 02300 /*-----------------------------------------------------------*/ 02301 02302 #if ( portCRITICAL_NESTING_IN_TCB == 1 ) 02303 02304 void vTaskEnterCritical( void ) 02305 { 02306 portDISABLE_INTERRUPTS(); 02307 02308 if( xSchedulerRunning != pdFALSE ) 02309 { 02310 pxCurrentTCB->uxCriticalNesting++; 02311 } 02312 } 02313 02314 #endif 02315 /*-----------------------------------------------------------*/ 02316 02317 #if ( portCRITICAL_NESTING_IN_TCB == 1 ) 02318 02319 void vTaskExitCritical( void ) 02320 { 02321 if( xSchedulerRunning != pdFALSE ) 02322 { 02323 if( pxCurrentTCB->uxCriticalNesting > 0 ) 02324 { 02325 pxCurrentTCB->uxCriticalNesting--; 02326 02327 if( pxCurrentTCB->uxCriticalNesting == 0 ) 02328 { 02329 portENABLE_INTERRUPTS(); 02330 } 02331 } 02332 } 02333 } 02334 02335 #endif 02336 /*-----------------------------------------------------------*/ 02337 void vApplicationTickHook( void ){ 02338 static unsigned long ulTicksSinceLastDisplay = 0; 02339 02340 /* Called from every tick interrupt as described in the comments at the top of this file. 02341 Have enough ticks passed to make it time to perform our health status check again? */ 02342 ulTicksSinceLastDisplay++; 02343 if( ulTicksSinceLastDisplay >= mainCHECK_DELAY ){ 02344 /* Reset the counter so these checks run again in mainCHECK_DELAY 02345 ticks time. */ 02346 ulTicksSinceLastDisplay = 0; 02347 } 02348 } 02349 02350 /*----------------------------------------------------------------------------------------------------------*/ 02351 02352 void vApplicationStackOverflowHook( xTaskHandle *pxTask, signed char *pcTaskName ) 02353 { 02354 /* This function will get called if a task overflows its stack. */ 02355 02356 ( void ) pxTask; 02357 ( void ) pcTaskName; 02358 for( ;; ); 02359 } 02360 02361
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