2 * FreeRTOS Kernel <DEVELOPMENT BRANCH>
3 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
5 * SPDX-License-Identifier: MIT
7 * Permission is hereby granted, free of charge, to any person obtaining a copy of
8 * this software and associated documentation files (the "Software"), to deal in
9 * the Software without restriction, including without limitation the rights to
10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
11 * the Software, and to permit persons to whom the Software is furnished to do so,
12 * subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included in all
15 * copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
19 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
20 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
21 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 * https://www.FreeRTOS.org
25 * https://github.com/FreeRTOS
29 /* Standard includes. */
32 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
33 * all the API functions to use the MPU wrappers. That should only be done when
34 * task.h is included from an application file. */
35 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
42 #if ( INCLUDE_xTimerPendFunctionCall == 1 ) && ( configUSE_TIMERS == 0 )
43 #error configUSE_TIMERS must be set to 1 to make the xTimerPendFunctionCall() function available.
46 /* Lint e9021, e961 and e750 are suppressed as a MISRA exception justified
47 * because the MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined
48 * for the header files above, but not in this file, in order to generate the
49 * correct privileged Vs unprivileged linkage and placement. */
50 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e9021 !e961 !e750. */
53 /* This entire source file will be skipped if the application is not configured
54 * to include software timer functionality. This #if is closed at the very bottom
55 * of this file. If you want to include software timer functionality then ensure
56 * configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
57 #if ( configUSE_TIMERS == 1 )
59 /* Misc definitions. */
60 #define tmrNO_DELAY ( ( TickType_t ) 0U )
61 #define tmrMAX_TIME_BEFORE_OVERFLOW ( ( TickType_t ) -1 )
63 /* The name assigned to the timer service task. This can be overridden by
64 * defining trmTIMER_SERVICE_TASK_NAME in FreeRTOSConfig.h. */
65 #ifndef configTIMER_SERVICE_TASK_NAME
66 #define configTIMER_SERVICE_TASK_NAME "Tmr Svc"
69 /* Bit definitions used in the ucStatus member of a timer structure. */
70 #define tmrSTATUS_IS_ACTIVE ( 0x01U )
71 #define tmrSTATUS_IS_STATICALLY_ALLOCATED ( 0x02U )
72 #define tmrSTATUS_IS_AUTORELOAD ( 0x04U )
74 /* The definition of the timers themselves. */
75 typedef struct tmrTimerControl /* The old naming convention is used to prevent breaking kernel aware debuggers. */
77 const char * pcTimerName; /**< Text name. This is not used by the kernel, it is included simply to make debugging easier. */ /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
78 ListItem_t xTimerListItem; /**< Standard linked list item as used by all kernel features for event management. */
79 TickType_t xTimerPeriodInTicks; /**< How quickly and often the timer expires. */
80 void * pvTimerID; /**< An ID to identify the timer. This allows the timer to be identified when the same callback is used for multiple timers. */
81 portTIMER_CALLBACK_ATTRIBUTE TimerCallbackFunction_t pxCallbackFunction; /**< The function that will be called when the timer expires. */
82 #if ( configUSE_TRACE_FACILITY == 1 )
83 UBaseType_t uxTimerNumber; /**< An ID assigned by trace tools such as FreeRTOS+Trace */
85 uint8_t ucStatus; /**< Holds bits to say if the timer was statically allocated or not, and if it is active or not. */
88 /* The old xTIMER name is maintained above then typedefed to the new Timer_t
89 * name below to enable the use of older kernel aware debuggers. */
90 typedef xTIMER Timer_t;
92 /* The definition of messages that can be sent and received on the timer queue.
93 * Two types of message can be queued - messages that manipulate a software timer,
94 * and messages that request the execution of a non-timer related callback. The
95 * two message types are defined in two separate structures, xTimerParametersType
96 * and xCallbackParametersType respectively. */
97 typedef struct tmrTimerParameters
99 TickType_t xMessageValue; /**< An optional value used by a subset of commands, for example, when changing the period of a timer. */
100 Timer_t * pxTimer; /**< The timer to which the command will be applied. */
104 typedef struct tmrCallbackParameters
106 portTIMER_CALLBACK_ATTRIBUTE
107 PendedFunction_t pxCallbackFunction; /* << The callback function to execute. */
108 void * pvParameter1; /* << The value that will be used as the callback functions first parameter. */
109 uint32_t ulParameter2; /* << The value that will be used as the callback functions second parameter. */
110 } CallbackParameters_t;
112 /* The structure that contains the two message types, along with an identifier
113 * that is used to determine which message type is valid. */
114 typedef struct tmrTimerQueueMessage
116 BaseType_t xMessageID; /**< The command being sent to the timer service task. */
119 TimerParameter_t xTimerParameters;
121 /* Don't include xCallbackParameters if it is not going to be used as
122 * it makes the structure (and therefore the timer queue) larger. */
123 #if ( INCLUDE_xTimerPendFunctionCall == 1 )
124 CallbackParameters_t xCallbackParameters;
125 #endif /* INCLUDE_xTimerPendFunctionCall */
127 } DaemonTaskMessage_t;
129 /*lint -save -e956 A manual analysis and inspection has been used to determine
130 * which static variables must be declared volatile. */
132 /* The list in which active timers are stored. Timers are referenced in expire
133 * time order, with the nearest expiry time at the front of the list. Only the
134 * timer service task is allowed to access these lists.
135 * xActiveTimerList1 and xActiveTimerList2 could be at function scope but that
136 * breaks some kernel aware debuggers, and debuggers that reply on removing the
137 * static qualifier. */
138 PRIVILEGED_DATA static List_t xActiveTimerList1;
139 PRIVILEGED_DATA static List_t xActiveTimerList2;
140 PRIVILEGED_DATA static List_t * pxCurrentTimerList;
141 PRIVILEGED_DATA static List_t * pxOverflowTimerList;
143 /* A queue that is used to send commands to the timer service task. */
144 PRIVILEGED_DATA static QueueHandle_t xTimerQueue = NULL;
145 PRIVILEGED_DATA static TaskHandle_t xTimerTaskHandle = NULL;
149 /*-----------------------------------------------------------*/
152 * Initialise the infrastructure used by the timer service task if it has not
153 * been initialised already.
155 static void prvCheckForValidListAndQueue( void ) PRIVILEGED_FUNCTION;
158 * The timer service task (daemon). Timer functionality is controlled by this
159 * task. Other tasks communicate with the timer service task using the
162 static portTASK_FUNCTION_PROTO( prvTimerTask, pvParameters ) PRIVILEGED_FUNCTION;
165 * Called by the timer service task to interpret and process a command it
166 * received on the timer queue.
168 static void prvProcessReceivedCommands( void ) PRIVILEGED_FUNCTION;
171 * Insert the timer into either xActiveTimerList1, or xActiveTimerList2,
172 * depending on if the expire time causes a timer counter overflow.
174 static BaseType_t prvInsertTimerInActiveList( Timer_t * const pxTimer,
175 const TickType_t xNextExpiryTime,
176 const TickType_t xTimeNow,
177 const TickType_t xCommandTime ) PRIVILEGED_FUNCTION;
180 * Reload the specified auto-reload timer. If the reloading is backlogged,
181 * clear the backlog, calling the callback for each additional reload. When
182 * this function returns, the next expiry time is after xTimeNow.
184 static void prvReloadTimer( Timer_t * const pxTimer,
185 TickType_t xExpiredTime,
186 const TickType_t xTimeNow ) PRIVILEGED_FUNCTION;
189 * An active timer has reached its expire time. Reload the timer if it is an
190 * auto-reload timer, then call its callback.
192 static void prvProcessExpiredTimer( const TickType_t xNextExpireTime,
193 const TickType_t xTimeNow ) PRIVILEGED_FUNCTION;
196 * The tick count has overflowed. Switch the timer lists after ensuring the
197 * current timer list does not still reference some timers.
199 static void prvSwitchTimerLists( void ) PRIVILEGED_FUNCTION;
202 * Obtain the current tick count, setting *pxTimerListsWereSwitched to pdTRUE
203 * if a tick count overflow occurred since prvSampleTimeNow() was last called.
205 static TickType_t prvSampleTimeNow( BaseType_t * const pxTimerListsWereSwitched ) PRIVILEGED_FUNCTION;
208 * If the timer list contains any active timers then return the expire time of
209 * the timer that will expire first and set *pxListWasEmpty to false. If the
210 * timer list does not contain any timers then return 0 and set *pxListWasEmpty
213 static TickType_t prvGetNextExpireTime( BaseType_t * const pxListWasEmpty ) PRIVILEGED_FUNCTION;
216 * If a timer has expired, process it. Otherwise, block the timer service task
217 * until either a timer does expire or a command is received.
219 static void prvProcessTimerOrBlockTask( const TickType_t xNextExpireTime,
220 BaseType_t xListWasEmpty ) PRIVILEGED_FUNCTION;
223 * Called after a Timer_t structure has been allocated either statically or
224 * dynamically to fill in the structure's members.
226 static void prvInitialiseNewTimer( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
227 const TickType_t xTimerPeriodInTicks,
228 const BaseType_t xAutoReload,
229 void * const pvTimerID,
230 TimerCallbackFunction_t pxCallbackFunction,
231 Timer_t * pxNewTimer ) PRIVILEGED_FUNCTION;
232 /*-----------------------------------------------------------*/
234 BaseType_t xTimerCreateTimerTask( void )
236 BaseType_t xReturn = pdFAIL;
238 traceENTER_xTimerCreateTimerTask();
240 /* This function is called when the scheduler is started if
241 * configUSE_TIMERS is set to 1. Check that the infrastructure used by the
242 * timer service task has been created/initialised. If timers have already
243 * been created then the initialisation will already have been performed. */
244 prvCheckForValidListAndQueue();
246 if( xTimerQueue != NULL )
248 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
250 StaticTask_t * pxTimerTaskTCBBuffer = NULL;
251 StackType_t * pxTimerTaskStackBuffer = NULL;
252 uint32_t ulTimerTaskStackSize;
254 vApplicationGetTimerTaskMemory( &pxTimerTaskTCBBuffer, &pxTimerTaskStackBuffer, &ulTimerTaskStackSize );
255 xTimerTaskHandle = xTaskCreateStatic( prvTimerTask,
256 configTIMER_SERVICE_TASK_NAME,
257 ulTimerTaskStackSize,
259 ( ( UBaseType_t ) configTIMER_TASK_PRIORITY ) | portPRIVILEGE_BIT,
260 pxTimerTaskStackBuffer,
261 pxTimerTaskTCBBuffer );
263 if( xTimerTaskHandle != NULL )
268 #else /* if ( configSUPPORT_STATIC_ALLOCATION == 1 ) */
270 xReturn = xTaskCreate( prvTimerTask,
271 configTIMER_SERVICE_TASK_NAME,
272 configTIMER_TASK_STACK_DEPTH,
274 ( ( UBaseType_t ) configTIMER_TASK_PRIORITY ) | portPRIVILEGE_BIT,
277 #endif /* configSUPPORT_STATIC_ALLOCATION */
281 mtCOVERAGE_TEST_MARKER();
284 configASSERT( xReturn );
286 traceRETURN_xTimerCreateTimerTask( xReturn );
290 /*-----------------------------------------------------------*/
292 #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
294 TimerHandle_t xTimerCreate( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
295 const TickType_t xTimerPeriodInTicks,
296 const BaseType_t xAutoReload,
297 void * const pvTimerID,
298 TimerCallbackFunction_t pxCallbackFunction )
300 Timer_t * pxNewTimer;
302 traceENTER_xTimerCreate( pcTimerName, xTimerPeriodInTicks, xAutoReload, pvTimerID, pxCallbackFunction );
304 pxNewTimer = ( Timer_t * ) pvPortMalloc( sizeof( Timer_t ) ); /*lint !e9087 !e9079 All values returned by pvPortMalloc() have at least the alignment required by the MCU's stack, and the first member of Timer_t is always a pointer to the timer's name. */
306 if( pxNewTimer != NULL )
308 /* Status is thus far zero as the timer is not created statically
309 * and has not been started. The auto-reload bit may get set in
310 * prvInitialiseNewTimer. */
311 pxNewTimer->ucStatus = 0x00;
312 prvInitialiseNewTimer( pcTimerName, xTimerPeriodInTicks, xAutoReload, pvTimerID, pxCallbackFunction, pxNewTimer );
315 traceRETURN_xTimerCreate( pxNewTimer );
320 #endif /* configSUPPORT_DYNAMIC_ALLOCATION */
321 /*-----------------------------------------------------------*/
323 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
325 TimerHandle_t xTimerCreateStatic( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
326 const TickType_t xTimerPeriodInTicks,
327 const BaseType_t xAutoReload,
328 void * const pvTimerID,
329 TimerCallbackFunction_t pxCallbackFunction,
330 StaticTimer_t * pxTimerBuffer )
332 Timer_t * pxNewTimer;
334 traceENTER_xTimerCreateStatic( pcTimerName, xTimerPeriodInTicks, xAutoReload, pvTimerID, pxCallbackFunction, pxTimerBuffer );
336 #if ( configASSERT_DEFINED == 1 )
338 /* Sanity check that the size of the structure used to declare a
339 * variable of type StaticTimer_t equals the size of the real timer
341 volatile size_t xSize = sizeof( StaticTimer_t );
342 configASSERT( xSize == sizeof( Timer_t ) );
343 ( void ) xSize; /* Keeps lint quiet when configASSERT() is not defined. */
345 #endif /* configASSERT_DEFINED */
347 /* A pointer to a StaticTimer_t structure MUST be provided, use it. */
348 configASSERT( pxTimerBuffer );
349 pxNewTimer = ( Timer_t * ) pxTimerBuffer; /*lint !e740 !e9087 StaticTimer_t is a pointer to a Timer_t, so guaranteed to be aligned and sized correctly (checked by an assert()), so this is safe. */
351 if( pxNewTimer != NULL )
353 /* Timers can be created statically or dynamically so note this
354 * timer was created statically in case it is later deleted. The
355 * auto-reload bit may get set in prvInitialiseNewTimer(). */
356 pxNewTimer->ucStatus = ( uint8_t ) tmrSTATUS_IS_STATICALLY_ALLOCATED;
358 prvInitialiseNewTimer( pcTimerName, xTimerPeriodInTicks, xAutoReload, pvTimerID, pxCallbackFunction, pxNewTimer );
361 traceRETURN_xTimerCreateStatic( pxNewTimer );
366 #endif /* configSUPPORT_STATIC_ALLOCATION */
367 /*-----------------------------------------------------------*/
369 static void prvInitialiseNewTimer( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
370 const TickType_t xTimerPeriodInTicks,
371 const BaseType_t xAutoReload,
372 void * const pvTimerID,
373 TimerCallbackFunction_t pxCallbackFunction,
374 Timer_t * pxNewTimer )
376 /* 0 is not a valid value for xTimerPeriodInTicks. */
377 configASSERT( ( xTimerPeriodInTicks > 0 ) );
379 /* Ensure the infrastructure used by the timer service task has been
380 * created/initialised. */
381 prvCheckForValidListAndQueue();
383 /* Initialise the timer structure members using the function
385 pxNewTimer->pcTimerName = pcTimerName;
386 pxNewTimer->xTimerPeriodInTicks = xTimerPeriodInTicks;
387 pxNewTimer->pvTimerID = pvTimerID;
388 pxNewTimer->pxCallbackFunction = pxCallbackFunction;
389 vListInitialiseItem( &( pxNewTimer->xTimerListItem ) );
391 if( xAutoReload != pdFALSE )
393 pxNewTimer->ucStatus |= ( uint8_t ) tmrSTATUS_IS_AUTORELOAD;
396 traceTIMER_CREATE( pxNewTimer );
398 /*-----------------------------------------------------------*/
400 BaseType_t xTimerGenericCommandFromTask( TimerHandle_t xTimer,
401 const BaseType_t xCommandID,
402 const TickType_t xOptionalValue,
403 BaseType_t * const pxHigherPriorityTaskWoken,
404 const TickType_t xTicksToWait )
406 BaseType_t xReturn = pdFAIL;
407 DaemonTaskMessage_t xMessage;
409 ( void ) pxHigherPriorityTaskWoken;
411 traceENTER_xTimerGenericCommandFromTask( xTimer, xCommandID, xOptionalValue, pxHigherPriorityTaskWoken, xTicksToWait );
413 configASSERT( xTimer );
415 /* Send a message to the timer service task to perform a particular action
416 * on a particular timer definition. */
417 if( xTimerQueue != NULL )
419 /* Send a command to the timer service task to start the xTimer timer. */
420 xMessage.xMessageID = xCommandID;
421 xMessage.u.xTimerParameters.xMessageValue = xOptionalValue;
422 xMessage.u.xTimerParameters.pxTimer = xTimer;
424 configASSERT( xCommandID < tmrFIRST_FROM_ISR_COMMAND );
426 if( xCommandID < tmrFIRST_FROM_ISR_COMMAND )
428 if( xTaskGetSchedulerState() == taskSCHEDULER_RUNNING )
430 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xTicksToWait );
434 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, tmrNO_DELAY );
438 traceTIMER_COMMAND_SEND( xTimer, xCommandID, xOptionalValue, xReturn );
442 mtCOVERAGE_TEST_MARKER();
445 traceRETURN_xTimerGenericCommandFromTask( xReturn );
449 /*-----------------------------------------------------------*/
451 BaseType_t xTimerGenericCommandFromISR( TimerHandle_t xTimer,
452 const BaseType_t xCommandID,
453 const TickType_t xOptionalValue,
454 BaseType_t * const pxHigherPriorityTaskWoken,
455 const TickType_t xTicksToWait )
457 BaseType_t xReturn = pdFAIL;
458 DaemonTaskMessage_t xMessage;
460 ( void ) xTicksToWait;
462 traceENTER_xTimerGenericCommandFromISR( xTimer, xCommandID, xOptionalValue, pxHigherPriorityTaskWoken, xTicksToWait );
464 configASSERT( xTimer );
466 /* Send a message to the timer service task to perform a particular action
467 * on a particular timer definition. */
468 if( xTimerQueue != NULL )
470 /* Send a command to the timer service task to start the xTimer timer. */
471 xMessage.xMessageID = xCommandID;
472 xMessage.u.xTimerParameters.xMessageValue = xOptionalValue;
473 xMessage.u.xTimerParameters.pxTimer = xTimer;
475 configASSERT( xCommandID >= tmrFIRST_FROM_ISR_COMMAND );
477 if( xCommandID >= tmrFIRST_FROM_ISR_COMMAND )
479 xReturn = xQueueSendToBackFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
482 traceTIMER_COMMAND_SEND( xTimer, xCommandID, xOptionalValue, xReturn );
486 mtCOVERAGE_TEST_MARKER();
489 traceRETURN_xTimerGenericCommandFromISR( xReturn );
493 /*-----------------------------------------------------------*/
495 TaskHandle_t xTimerGetTimerDaemonTaskHandle( void )
497 traceENTER_xTimerGetTimerDaemonTaskHandle();
499 /* If xTimerGetTimerDaemonTaskHandle() is called before the scheduler has been
500 * started, then xTimerTaskHandle will be NULL. */
501 configASSERT( ( xTimerTaskHandle != NULL ) );
503 traceRETURN_xTimerGetTimerDaemonTaskHandle( xTimerTaskHandle );
505 return xTimerTaskHandle;
507 /*-----------------------------------------------------------*/
509 TickType_t xTimerGetPeriod( TimerHandle_t xTimer )
511 Timer_t * pxTimer = xTimer;
513 traceENTER_xTimerGetPeriod( xTimer );
515 configASSERT( xTimer );
517 traceRETURN_xTimerGetPeriod( pxTimer->xTimerPeriodInTicks );
519 return pxTimer->xTimerPeriodInTicks;
521 /*-----------------------------------------------------------*/
523 void vTimerSetReloadMode( TimerHandle_t xTimer,
524 const BaseType_t xAutoReload )
526 Timer_t * pxTimer = xTimer;
528 traceENTER_vTimerSetReloadMode( xTimer, xAutoReload );
530 configASSERT( xTimer );
531 taskENTER_CRITICAL();
533 if( xAutoReload != pdFALSE )
535 pxTimer->ucStatus |= ( uint8_t ) tmrSTATUS_IS_AUTORELOAD;
539 pxTimer->ucStatus &= ( ( uint8_t ) ~tmrSTATUS_IS_AUTORELOAD );
544 traceRETURN_vTimerSetReloadMode();
546 /*-----------------------------------------------------------*/
548 BaseType_t xTimerGetReloadMode( TimerHandle_t xTimer )
550 Timer_t * pxTimer = xTimer;
553 traceENTER_xTimerGetReloadMode( xTimer );
555 configASSERT( xTimer );
556 taskENTER_CRITICAL();
558 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) == 0 )
560 /* Not an auto-reload timer. */
565 /* Is an auto-reload timer. */
571 traceRETURN_xTimerGetReloadMode( xReturn );
576 UBaseType_t uxTimerGetReloadMode( TimerHandle_t xTimer )
578 UBaseType_t uxReturn;
580 traceENTER_uxTimerGetReloadMode( xTimer );
582 uxReturn = ( UBaseType_t ) xTimerGetReloadMode( xTimer );
584 traceRETURN_uxTimerGetReloadMode( uxReturn );
588 /*-----------------------------------------------------------*/
590 TickType_t xTimerGetExpiryTime( TimerHandle_t xTimer )
592 Timer_t * pxTimer = xTimer;
595 traceENTER_xTimerGetExpiryTime( xTimer );
597 configASSERT( xTimer );
598 xReturn = listGET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ) );
600 traceRETURN_xTimerGetExpiryTime( xReturn );
604 /*-----------------------------------------------------------*/
606 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
607 BaseType_t xTimerGetStaticBuffer( TimerHandle_t xTimer,
608 StaticTimer_t ** ppxTimerBuffer )
611 Timer_t * pxTimer = xTimer;
613 traceENTER_xTimerGetStaticBuffer( xTimer, ppxTimerBuffer );
615 configASSERT( ppxTimerBuffer != NULL );
617 if( ( pxTimer->ucStatus & tmrSTATUS_IS_STATICALLY_ALLOCATED ) != 0 )
619 *ppxTimerBuffer = ( StaticTimer_t * ) pxTimer;
627 traceRETURN_xTimerGetStaticBuffer( xReturn );
631 #endif /* configSUPPORT_STATIC_ALLOCATION */
632 /*-----------------------------------------------------------*/
634 const char * pcTimerGetName( TimerHandle_t xTimer ) /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
636 Timer_t * pxTimer = xTimer;
638 traceENTER_pcTimerGetName( xTimer );
640 configASSERT( xTimer );
642 traceRETURN_pcTimerGetName( pxTimer->pcTimerName );
644 return pxTimer->pcTimerName;
646 /*-----------------------------------------------------------*/
648 static void prvReloadTimer( Timer_t * const pxTimer,
649 TickType_t xExpiredTime,
650 const TickType_t xTimeNow )
652 /* Insert the timer into the appropriate list for the next expiry time.
653 * If the next expiry time has already passed, advance the expiry time,
654 * call the callback function, and try again. */
655 while( prvInsertTimerInActiveList( pxTimer, ( xExpiredTime + pxTimer->xTimerPeriodInTicks ), xTimeNow, xExpiredTime ) != pdFALSE )
657 /* Advance the expiry time. */
658 xExpiredTime += pxTimer->xTimerPeriodInTicks;
660 /* Call the timer callback. */
661 traceTIMER_EXPIRED( pxTimer );
662 pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );
665 /*-----------------------------------------------------------*/
667 static void prvProcessExpiredTimer( const TickType_t xNextExpireTime,
668 const TickType_t xTimeNow )
670 Timer_t * const pxTimer = ( Timer_t * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList ); /*lint !e9087 !e9079 void * is used as this macro is used with tasks and co-routines too. Alignment is known to be fine as the type of the pointer stored and retrieved is the same. */
672 /* Remove the timer from the list of active timers. A check has already
673 * been performed to ensure the list is not empty. */
675 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
677 /* If the timer is an auto-reload timer then calculate the next
678 * expiry time and re-insert the timer in the list of active timers. */
679 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) != 0 )
681 prvReloadTimer( pxTimer, xNextExpireTime, xTimeNow );
685 pxTimer->ucStatus &= ( ( uint8_t ) ~tmrSTATUS_IS_ACTIVE );
688 /* Call the timer callback. */
689 traceTIMER_EXPIRED( pxTimer );
690 pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );
692 /*-----------------------------------------------------------*/
694 static portTASK_FUNCTION( prvTimerTask, pvParameters )
696 TickType_t xNextExpireTime;
697 BaseType_t xListWasEmpty;
699 /* Just to avoid compiler warnings. */
700 ( void ) pvParameters;
702 #if ( configUSE_DAEMON_TASK_STARTUP_HOOK == 1 )
704 /* Allow the application writer to execute some code in the context of
705 * this task at the point the task starts executing. This is useful if the
706 * application includes initialisation code that would benefit from
707 * executing after the scheduler has been started. */
708 vApplicationDaemonTaskStartupHook();
710 #endif /* configUSE_DAEMON_TASK_STARTUP_HOOK */
712 for( ; configCONTROL_INFINITE_LOOP(); )
714 /* Query the timers list to see if it contains any timers, and if so,
715 * obtain the time at which the next timer will expire. */
716 xNextExpireTime = prvGetNextExpireTime( &xListWasEmpty );
718 /* If a timer has expired, process it. Otherwise, block this task
719 * until either a timer does expire, or a command is received. */
720 prvProcessTimerOrBlockTask( xNextExpireTime, xListWasEmpty );
722 /* Empty the command queue. */
723 prvProcessReceivedCommands();
726 /*-----------------------------------------------------------*/
728 static void prvProcessTimerOrBlockTask( const TickType_t xNextExpireTime,
729 BaseType_t xListWasEmpty )
732 BaseType_t xTimerListsWereSwitched;
736 /* Obtain the time now to make an assessment as to whether the timer
737 * has expired or not. If obtaining the time causes the lists to switch
738 * then don't process this timer as any timers that remained in the list
739 * when the lists were switched will have been processed within the
740 * prvSampleTimeNow() function. */
741 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
743 if( xTimerListsWereSwitched == pdFALSE )
745 /* The tick count has not overflowed, has the timer expired? */
746 if( ( xListWasEmpty == pdFALSE ) && ( xNextExpireTime <= xTimeNow ) )
748 ( void ) xTaskResumeAll();
749 prvProcessExpiredTimer( xNextExpireTime, xTimeNow );
753 /* The tick count has not overflowed, and the next expire
754 * time has not been reached yet. This task should therefore
755 * block to wait for the next expire time or a command to be
756 * received - whichever comes first. The following line cannot
757 * be reached unless xNextExpireTime > xTimeNow, except in the
758 * case when the current timer list is empty. */
759 if( xListWasEmpty != pdFALSE )
761 /* The current timer list is empty - is the overflow list
763 xListWasEmpty = listLIST_IS_EMPTY( pxOverflowTimerList );
766 vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ), xListWasEmpty );
768 if( xTaskResumeAll() == pdFALSE )
770 /* Yield to wait for either a command to arrive, or the
771 * block time to expire. If a command arrived between the
772 * critical section being exited and this yield then the yield
773 * will not cause the task to block. */
774 taskYIELD_WITHIN_API();
778 mtCOVERAGE_TEST_MARKER();
784 ( void ) xTaskResumeAll();
788 /*-----------------------------------------------------------*/
790 static TickType_t prvGetNextExpireTime( BaseType_t * const pxListWasEmpty )
792 TickType_t xNextExpireTime;
794 /* Timers are listed in expiry time order, with the head of the list
795 * referencing the task that will expire first. Obtain the time at which
796 * the timer with the nearest expiry time will expire. If there are no
797 * active timers then just set the next expire time to 0. That will cause
798 * this task to unblock when the tick count overflows, at which point the
799 * timer lists will be switched and the next expiry time can be
801 *pxListWasEmpty = listLIST_IS_EMPTY( pxCurrentTimerList );
803 if( *pxListWasEmpty == pdFALSE )
805 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
809 /* Ensure the task unblocks when the tick count rolls over. */
810 xNextExpireTime = ( TickType_t ) 0U;
813 return xNextExpireTime;
815 /*-----------------------------------------------------------*/
817 static TickType_t prvSampleTimeNow( BaseType_t * const pxTimerListsWereSwitched )
820 PRIVILEGED_DATA static TickType_t xLastTime = ( TickType_t ) 0U; /*lint !e956 Variable is only accessible to one task. */
822 xTimeNow = xTaskGetTickCount();
824 if( xTimeNow < xLastTime )
826 prvSwitchTimerLists();
827 *pxTimerListsWereSwitched = pdTRUE;
831 *pxTimerListsWereSwitched = pdFALSE;
834 xLastTime = xTimeNow;
838 /*-----------------------------------------------------------*/
840 static BaseType_t prvInsertTimerInActiveList( Timer_t * const pxTimer,
841 const TickType_t xNextExpiryTime,
842 const TickType_t xTimeNow,
843 const TickType_t xCommandTime )
845 BaseType_t xProcessTimerNow = pdFALSE;
847 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xNextExpiryTime );
848 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
850 if( xNextExpiryTime <= xTimeNow )
852 /* Has the expiry time elapsed between the command to start/reset a
853 * timer was issued, and the time the command was processed? */
854 if( ( ( TickType_t ) ( xTimeNow - xCommandTime ) ) >= pxTimer->xTimerPeriodInTicks ) /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
856 /* The time between a command being issued and the command being
857 * processed actually exceeds the timers period. */
858 xProcessTimerNow = pdTRUE;
862 vListInsert( pxOverflowTimerList, &( pxTimer->xTimerListItem ) );
867 if( ( xTimeNow < xCommandTime ) && ( xNextExpiryTime >= xCommandTime ) )
869 /* If, since the command was issued, the tick count has overflowed
870 * but the expiry time has not, then the timer must have already passed
871 * its expiry time and should be processed immediately. */
872 xProcessTimerNow = pdTRUE;
876 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
880 return xProcessTimerNow;
882 /*-----------------------------------------------------------*/
884 static void prvProcessReceivedCommands( void )
886 DaemonTaskMessage_t xMessage;
888 BaseType_t xTimerListsWereSwitched;
891 while( xQueueReceive( xTimerQueue, &xMessage, tmrNO_DELAY ) != pdFAIL ) /*lint !e603 xMessage does not have to be initialised as it is passed out, not in, and it is not used unless xQueueReceive() returns pdTRUE. */
893 #if ( INCLUDE_xTimerPendFunctionCall == 1 )
895 /* Negative commands are pended function calls rather than timer
897 if( xMessage.xMessageID < ( BaseType_t ) 0 )
899 const CallbackParameters_t * const pxCallback = &( xMessage.u.xCallbackParameters );
901 /* The timer uses the xCallbackParameters member to request a
902 * callback be executed. Check the callback is not NULL. */
903 configASSERT( pxCallback );
905 /* Call the function. */
906 pxCallback->pxCallbackFunction( pxCallback->pvParameter1, pxCallback->ulParameter2 );
910 mtCOVERAGE_TEST_MARKER();
913 #endif /* INCLUDE_xTimerPendFunctionCall */
915 /* Commands that are positive are timer commands rather than pended
917 if( xMessage.xMessageID >= ( BaseType_t ) 0 )
919 /* The messages uses the xTimerParameters member to work on a
921 pxTimer = xMessage.u.xTimerParameters.pxTimer;
923 if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE ) /*lint !e961. The cast is only redundant when NULL is passed into the macro. */
925 /* The timer is in a list, remove it. */
926 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
930 mtCOVERAGE_TEST_MARKER();
933 traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.u.xTimerParameters.xMessageValue );
935 /* In this case the xTimerListsWereSwitched parameter is not used, but
936 * it must be present in the function call. prvSampleTimeNow() must be
937 * called after the message is received from xTimerQueue so there is no
938 * possibility of a higher priority task adding a message to the message
939 * queue with a time that is ahead of the timer daemon task (because it
940 * pre-empted the timer daemon task after the xTimeNow value was set). */
941 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
943 switch( xMessage.xMessageID )
945 case tmrCOMMAND_START:
946 case tmrCOMMAND_START_FROM_ISR:
947 case tmrCOMMAND_RESET:
948 case tmrCOMMAND_RESET_FROM_ISR:
949 /* Start or restart a timer. */
950 pxTimer->ucStatus |= ( uint8_t ) tmrSTATUS_IS_ACTIVE;
952 if( prvInsertTimerInActiveList( pxTimer, xMessage.u.xTimerParameters.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.u.xTimerParameters.xMessageValue ) != pdFALSE )
954 /* The timer expired before it was added to the active
955 * timer list. Process it now. */
956 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) != 0 )
958 prvReloadTimer( pxTimer, xMessage.u.xTimerParameters.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow );
962 pxTimer->ucStatus &= ( ( uint8_t ) ~tmrSTATUS_IS_ACTIVE );
965 /* Call the timer callback. */
966 traceTIMER_EXPIRED( pxTimer );
967 pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );
971 mtCOVERAGE_TEST_MARKER();
976 case tmrCOMMAND_STOP:
977 case tmrCOMMAND_STOP_FROM_ISR:
978 /* The timer has already been removed from the active list. */
979 pxTimer->ucStatus &= ( ( uint8_t ) ~tmrSTATUS_IS_ACTIVE );
982 case tmrCOMMAND_CHANGE_PERIOD:
983 case tmrCOMMAND_CHANGE_PERIOD_FROM_ISR:
984 pxTimer->ucStatus |= ( uint8_t ) tmrSTATUS_IS_ACTIVE;
985 pxTimer->xTimerPeriodInTicks = xMessage.u.xTimerParameters.xMessageValue;
986 configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );
988 /* The new period does not really have a reference, and can
989 * be longer or shorter than the old one. The command time is
990 * therefore set to the current time, and as the period cannot
991 * be zero the next expiry time can only be in the future,
992 * meaning (unlike for the xTimerStart() case above) there is
993 * no fail case that needs to be handled here. */
994 ( void ) prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );
997 case tmrCOMMAND_DELETE:
998 #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
1000 /* The timer has already been removed from the active list,
1001 * just free up the memory if the memory was dynamically
1003 if( ( pxTimer->ucStatus & tmrSTATUS_IS_STATICALLY_ALLOCATED ) == ( uint8_t ) 0 )
1005 vPortFree( pxTimer );
1009 pxTimer->ucStatus &= ( ( uint8_t ) ~tmrSTATUS_IS_ACTIVE );
1012 #else /* if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) */
1014 /* If dynamic allocation is not enabled, the memory
1015 * could not have been dynamically allocated. So there is
1016 * no need to free the memory - just mark the timer as
1018 pxTimer->ucStatus &= ( ( uint8_t ) ~tmrSTATUS_IS_ACTIVE );
1020 #endif /* configSUPPORT_DYNAMIC_ALLOCATION */
1024 /* Don't expect to get here. */
1030 /*-----------------------------------------------------------*/
1032 static void prvSwitchTimerLists( void )
1034 TickType_t xNextExpireTime;
1037 /* The tick count has overflowed. The timer lists must be switched.
1038 * If there are any timers still referenced from the current timer list
1039 * then they must have expired and should be processed before the lists
1041 while( listLIST_IS_EMPTY( pxCurrentTimerList ) == pdFALSE )
1043 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
1045 /* Process the expired timer. For auto-reload timers, be careful to
1046 * process only expirations that occur on the current list. Further
1047 * expirations must wait until after the lists are switched. */
1048 prvProcessExpiredTimer( xNextExpireTime, tmrMAX_TIME_BEFORE_OVERFLOW );
1051 pxTemp = pxCurrentTimerList;
1052 pxCurrentTimerList = pxOverflowTimerList;
1053 pxOverflowTimerList = pxTemp;
1055 /*-----------------------------------------------------------*/
1057 static void prvCheckForValidListAndQueue( void )
1059 /* Check that the list from which active timers are referenced, and the
1060 * queue used to communicate with the timer service, have been
1062 taskENTER_CRITICAL();
1064 if( xTimerQueue == NULL )
1066 vListInitialise( &xActiveTimerList1 );
1067 vListInitialise( &xActiveTimerList2 );
1068 pxCurrentTimerList = &xActiveTimerList1;
1069 pxOverflowTimerList = &xActiveTimerList2;
1071 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
1073 /* The timer queue is allocated statically in case
1074 * configSUPPORT_DYNAMIC_ALLOCATION is 0. */
1075 PRIVILEGED_DATA static StaticQueue_t xStaticTimerQueue; /*lint !e956 Ok to declare in this manner to prevent additional conditional compilation guards in other locations. */
1076 PRIVILEGED_DATA static uint8_t ucStaticTimerQueueStorage[ ( size_t ) configTIMER_QUEUE_LENGTH * sizeof( DaemonTaskMessage_t ) ]; /*lint !e956 Ok to declare in this manner to prevent additional conditional compilation guards in other locations. */
1078 xTimerQueue = xQueueCreateStatic( ( UBaseType_t ) configTIMER_QUEUE_LENGTH, ( UBaseType_t ) sizeof( DaemonTaskMessage_t ), &( ucStaticTimerQueueStorage[ 0 ] ), &xStaticTimerQueue );
1082 xTimerQueue = xQueueCreate( ( UBaseType_t ) configTIMER_QUEUE_LENGTH, sizeof( DaemonTaskMessage_t ) );
1084 #endif /* if ( configSUPPORT_STATIC_ALLOCATION == 1 ) */
1086 #if ( configQUEUE_REGISTRY_SIZE > 0 )
1088 if( xTimerQueue != NULL )
1090 vQueueAddToRegistry( xTimerQueue, "TmrQ" );
1094 mtCOVERAGE_TEST_MARKER();
1097 #endif /* configQUEUE_REGISTRY_SIZE */
1101 mtCOVERAGE_TEST_MARKER();
1104 taskEXIT_CRITICAL();
1106 /*-----------------------------------------------------------*/
1108 BaseType_t xTimerIsTimerActive( TimerHandle_t xTimer )
1111 Timer_t * pxTimer = xTimer;
1113 traceENTER_xTimerIsTimerActive( xTimer );
1115 configASSERT( xTimer );
1117 /* Is the timer in the list of active timers? */
1118 taskENTER_CRITICAL();
1120 if( ( pxTimer->ucStatus & tmrSTATUS_IS_ACTIVE ) == 0 )
1129 taskEXIT_CRITICAL();
1131 traceRETURN_xTimerIsTimerActive( xReturn );
1134 } /*lint !e818 Can't be pointer to const due to the typedef. */
1135 /*-----------------------------------------------------------*/
1137 void * pvTimerGetTimerID( const TimerHandle_t xTimer )
1139 Timer_t * const pxTimer = xTimer;
1142 traceENTER_pvTimerGetTimerID( xTimer );
1144 configASSERT( xTimer );
1146 taskENTER_CRITICAL();
1148 pvReturn = pxTimer->pvTimerID;
1150 taskEXIT_CRITICAL();
1152 traceRETURN_pvTimerGetTimerID( pvReturn );
1156 /*-----------------------------------------------------------*/
1158 void vTimerSetTimerID( TimerHandle_t xTimer,
1161 Timer_t * const pxTimer = xTimer;
1163 traceENTER_vTimerSetTimerID( xTimer, pvNewID );
1165 configASSERT( xTimer );
1167 taskENTER_CRITICAL();
1169 pxTimer->pvTimerID = pvNewID;
1171 taskEXIT_CRITICAL();
1173 traceRETURN_vTimerSetTimerID();
1175 /*-----------------------------------------------------------*/
1177 #if ( INCLUDE_xTimerPendFunctionCall == 1 )
1179 BaseType_t xTimerPendFunctionCallFromISR( PendedFunction_t xFunctionToPend,
1180 void * pvParameter1,
1181 uint32_t ulParameter2,
1182 BaseType_t * pxHigherPriorityTaskWoken )
1184 DaemonTaskMessage_t xMessage;
1187 traceENTER_xTimerPendFunctionCallFromISR( xFunctionToPend, pvParameter1, ulParameter2, pxHigherPriorityTaskWoken );
1189 /* Complete the message with the function parameters and post it to the
1191 xMessage.xMessageID = tmrCOMMAND_EXECUTE_CALLBACK_FROM_ISR;
1192 xMessage.u.xCallbackParameters.pxCallbackFunction = xFunctionToPend;
1193 xMessage.u.xCallbackParameters.pvParameter1 = pvParameter1;
1194 xMessage.u.xCallbackParameters.ulParameter2 = ulParameter2;
1196 xReturn = xQueueSendFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
1198 tracePEND_FUNC_CALL_FROM_ISR( xFunctionToPend, pvParameter1, ulParameter2, xReturn );
1199 traceRETURN_xTimerPendFunctionCallFromISR( xReturn );
1204 #endif /* INCLUDE_xTimerPendFunctionCall */
1205 /*-----------------------------------------------------------*/
1207 #if ( INCLUDE_xTimerPendFunctionCall == 1 )
1209 BaseType_t xTimerPendFunctionCall( PendedFunction_t xFunctionToPend,
1210 void * pvParameter1,
1211 uint32_t ulParameter2,
1212 TickType_t xTicksToWait )
1214 DaemonTaskMessage_t xMessage;
1217 traceENTER_xTimerPendFunctionCall( xFunctionToPend, pvParameter1, ulParameter2, xTicksToWait );
1219 /* This function can only be called after a timer has been created or
1220 * after the scheduler has been started because, until then, the timer
1221 * queue does not exist. */
1222 configASSERT( xTimerQueue );
1224 /* Complete the message with the function parameters and post it to the
1226 xMessage.xMessageID = tmrCOMMAND_EXECUTE_CALLBACK;
1227 xMessage.u.xCallbackParameters.pxCallbackFunction = xFunctionToPend;
1228 xMessage.u.xCallbackParameters.pvParameter1 = pvParameter1;
1229 xMessage.u.xCallbackParameters.ulParameter2 = ulParameter2;
1231 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xTicksToWait );
1233 tracePEND_FUNC_CALL( xFunctionToPend, pvParameter1, ulParameter2, xReturn );
1234 traceRETURN_xTimerPendFunctionCall( xReturn );
1239 #endif /* INCLUDE_xTimerPendFunctionCall */
1240 /*-----------------------------------------------------------*/
1242 #if ( configUSE_TRACE_FACILITY == 1 )
1244 UBaseType_t uxTimerGetTimerNumber( TimerHandle_t xTimer )
1246 traceENTER_uxTimerGetTimerNumber( xTimer );
1248 traceRETURN_uxTimerGetTimerNumber( ( ( Timer_t * ) xTimer )->uxTimerNumber );
1250 return ( ( Timer_t * ) xTimer )->uxTimerNumber;
1253 #endif /* configUSE_TRACE_FACILITY */
1254 /*-----------------------------------------------------------*/
1256 #if ( configUSE_TRACE_FACILITY == 1 )
1258 void vTimerSetTimerNumber( TimerHandle_t xTimer,
1259 UBaseType_t uxTimerNumber )
1261 traceENTER_vTimerSetTimerNumber( xTimer, uxTimerNumber );
1263 ( ( Timer_t * ) xTimer )->uxTimerNumber = uxTimerNumber;
1265 traceRETURN_vTimerSetTimerNumber();
1268 #endif /* configUSE_TRACE_FACILITY */
1269 /*-----------------------------------------------------------*/
1271 /* This entire source file will be skipped if the application is not configured
1272 * to include software timer functionality. If you want to include software timer
1273 * functionality then ensure configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
1274 #endif /* configUSE_TIMERS == 1 */