source: S-port/trunk/Middlewares/Third_Party/FreeRTOS/Source/timers.c

Last change on this file was 1, checked in by AlexLir, 3 years ago
File size: 40.2 KB
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[1]1/*
2 * FreeRTOS Kernel V10.3.1
3 * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a copy of
6 * this software and associated documentation files (the "Software"), to deal in
7 * the Software without restriction, including without limitation the rights to
8 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
9 * the Software, and to permit persons to whom the Software is furnished to do so,
10 * subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in all
13 * copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
17 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
18 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
19 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * http://www.FreeRTOS.org
23 * http://aws.amazon.com/freertos
24 *
25 * 1 tab == 4 spaces!
26 */
27
28/* Standard includes. */
29#include <stdlib.h>
30
31/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
32all the API functions to use the MPU wrappers. That should only be done when
33task.h is included from an application file. */
34#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
35
36#include "FreeRTOS.h"
37#include "task.h"
38#include "queue.h"
39#include "timers.h"
40
41#if ( INCLUDE_xTimerPendFunctionCall == 1 ) && ( configUSE_TIMERS == 0 )
42 #error configUSE_TIMERS must be set to 1 to make the xTimerPendFunctionCall() function available.
43#endif
44
45/* Lint e9021, e961 and e750 are suppressed as a MISRA exception justified
46because the MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined
47for the header files above, but not in this file, in order to generate the
48correct privileged Vs unprivileged linkage and placement. */
49#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e9021 !e961 !e750. */
50
51
52/* This entire source file will be skipped if the application is not configured
53to include software timer functionality. This #if is closed at the very bottom
54of this file. If you want to include software timer functionality then ensure
55configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
56#if ( configUSE_TIMERS == 1 )
57
58/* Misc definitions. */
59#define tmrNO_DELAY ( TickType_t ) 0U
60
61/* The name assigned to the timer service task. This can be overridden by
62defining trmTIMER_SERVICE_TASK_NAME in FreeRTOSConfig.h. */
63#ifndef configTIMER_SERVICE_TASK_NAME
64 #define configTIMER_SERVICE_TASK_NAME "Tmr Svc"
65#endif
66
67/* Bit definitions used in the ucStatus member of a timer structure. */
68#define tmrSTATUS_IS_ACTIVE ( ( uint8_t ) 0x01 )
69#define tmrSTATUS_IS_STATICALLY_ALLOCATED ( ( uint8_t ) 0x02 )
70#define tmrSTATUS_IS_AUTORELOAD ( ( uint8_t ) 0x04 )
71
72/* The definition of the timers themselves. */
73typedef struct tmrTimerControl /* The old naming convention is used to prevent breaking kernel aware debuggers. */
74{
75 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. */
76 ListItem_t xTimerListItem; /*<< Standard linked list item as used by all kernel features for event management. */
77 TickType_t xTimerPeriodInTicks;/*<< How quickly and often the timer expires. */
78 void *pvTimerID; /*<< An ID to identify the timer. This allows the timer to be identified when the same callback is used for multiple timers. */
79 TimerCallbackFunction_t pxCallbackFunction; /*<< The function that will be called when the timer expires. */
80 #if( configUSE_TRACE_FACILITY == 1 )
81 UBaseType_t uxTimerNumber; /*<< An ID assigned by trace tools such as FreeRTOS+Trace */
82 #endif
83 uint8_t ucStatus; /*<< Holds bits to say if the timer was statically allocated or not, and if it is active or not. */
84} xTIMER;
85
86/* The old xTIMER name is maintained above then typedefed to the new Timer_t
87name below to enable the use of older kernel aware debuggers. */
88typedef xTIMER Timer_t;
89
90/* The definition of messages that can be sent and received on the timer queue.
91Two types of message can be queued - messages that manipulate a software timer,
92and messages that request the execution of a non-timer related callback. The
93two message types are defined in two separate structures, xTimerParametersType
94and xCallbackParametersType respectively. */
95typedef struct tmrTimerParameters
96{
97 TickType_t xMessageValue; /*<< An optional value used by a subset of commands, for example, when changing the period of a timer. */
98 Timer_t * pxTimer; /*<< The timer to which the command will be applied. */
99} TimerParameter_t;
100
101
102typedef struct tmrCallbackParameters
103{
104 PendedFunction_t pxCallbackFunction; /* << The callback function to execute. */
105 void *pvParameter1; /* << The value that will be used as the callback functions first parameter. */
106 uint32_t ulParameter2; /* << The value that will be used as the callback functions second parameter. */
107} CallbackParameters_t;
108
109/* The structure that contains the two message types, along with an identifier
110that is used to determine which message type is valid. */
111typedef struct tmrTimerQueueMessage
112{
113 BaseType_t xMessageID; /*<< The command being sent to the timer service task. */
114 union
115 {
116 TimerParameter_t xTimerParameters;
117
118 /* Don't include xCallbackParameters if it is not going to be used as
119 it makes the structure (and therefore the timer queue) larger. */
120 #if ( INCLUDE_xTimerPendFunctionCall == 1 )
121 CallbackParameters_t xCallbackParameters;
122 #endif /* INCLUDE_xTimerPendFunctionCall */
123 } u;
124} DaemonTaskMessage_t;
125
126/*lint -save -e956 A manual analysis and inspection has been used to determine
127which static variables must be declared volatile. */
128
129/* The list in which active timers are stored. Timers are referenced in expire
130time order, with the nearest expiry time at the front of the list. Only the
131timer service task is allowed to access these lists.
132xActiveTimerList1 and xActiveTimerList2 could be at function scope but that
133breaks some kernel aware debuggers, and debuggers that reply on removing the
134static qualifier. */
135PRIVILEGED_DATA static List_t xActiveTimerList1;
136PRIVILEGED_DATA static List_t xActiveTimerList2;
137PRIVILEGED_DATA static List_t *pxCurrentTimerList;
138PRIVILEGED_DATA static List_t *pxOverflowTimerList;
139
140/* A queue that is used to send commands to the timer service task. */
141PRIVILEGED_DATA static QueueHandle_t xTimerQueue = NULL;
142PRIVILEGED_DATA static TaskHandle_t xTimerTaskHandle = NULL;
143
144/*lint -restore */
145
146/*-----------------------------------------------------------*/
147
148#if( configSUPPORT_STATIC_ALLOCATION == 1 )
149
150 /* If static allocation is supported then the application must provide the
151 following callback function - which enables the application to optionally
152 provide the memory that will be used by the timer task as the task's stack
153 and TCB. */
154 extern void vApplicationGetTimerTaskMemory( StaticTask_t **ppxTimerTaskTCBBuffer, StackType_t **ppxTimerTaskStackBuffer, uint32_t *pulTimerTaskStackSize );
155
156#endif
157
158/*
159 * Initialise the infrastructure used by the timer service task if it has not
160 * been initialised already.
161 */
162static void prvCheckForValidListAndQueue( void ) PRIVILEGED_FUNCTION;
163
164/*
165 * The timer service task (daemon). Timer functionality is controlled by this
166 * task. Other tasks communicate with the timer service task using the
167 * xTimerQueue queue.
168 */
169static portTASK_FUNCTION_PROTO( prvTimerTask, pvParameters ) PRIVILEGED_FUNCTION;
170
171/*
172 * Called by the timer service task to interpret and process a command it
173 * received on the timer queue.
174 */
175static void prvProcessReceivedCommands( void ) PRIVILEGED_FUNCTION;
176
177/*
178 * Insert the timer into either xActiveTimerList1, or xActiveTimerList2,
179 * depending on if the expire time causes a timer counter overflow.
180 */
181static BaseType_t prvInsertTimerInActiveList( Timer_t * const pxTimer, const TickType_t xNextExpiryTime, const TickType_t xTimeNow, const TickType_t xCommandTime ) PRIVILEGED_FUNCTION;
182
183/*
184 * An active timer has reached its expire time. Reload the timer if it is an
185 * auto-reload timer, then call its callback.
186 */
187static void prvProcessExpiredTimer( const TickType_t xNextExpireTime, const TickType_t xTimeNow ) PRIVILEGED_FUNCTION;
188
189/*
190 * The tick count has overflowed. Switch the timer lists after ensuring the
191 * current timer list does not still reference some timers.
192 */
193static void prvSwitchTimerLists( void ) PRIVILEGED_FUNCTION;
194
195/*
196 * Obtain the current tick count, setting *pxTimerListsWereSwitched to pdTRUE
197 * if a tick count overflow occurred since prvSampleTimeNow() was last called.
198 */
199static TickType_t prvSampleTimeNow( BaseType_t * const pxTimerListsWereSwitched ) PRIVILEGED_FUNCTION;
200
201/*
202 * If the timer list contains any active timers then return the expire time of
203 * the timer that will expire first and set *pxListWasEmpty to false. If the
204 * timer list does not contain any timers then return 0 and set *pxListWasEmpty
205 * to pdTRUE.
206 */
207static TickType_t prvGetNextExpireTime( BaseType_t * const pxListWasEmpty ) PRIVILEGED_FUNCTION;
208
209/*
210 * If a timer has expired, process it. Otherwise, block the timer service task
211 * until either a timer does expire or a command is received.
212 */
213static void prvProcessTimerOrBlockTask( const TickType_t xNextExpireTime, BaseType_t xListWasEmpty ) PRIVILEGED_FUNCTION;
214
215/*
216 * Called after a Timer_t structure has been allocated either statically or
217 * dynamically to fill in the structure's members.
218 */
219static void prvInitialiseNewTimer( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
220 const TickType_t xTimerPeriodInTicks,
221 const UBaseType_t uxAutoReload,
222 void * const pvTimerID,
223 TimerCallbackFunction_t pxCallbackFunction,
224 Timer_t *pxNewTimer ) PRIVILEGED_FUNCTION;
225/*-----------------------------------------------------------*/
226
227BaseType_t xTimerCreateTimerTask( void )
228{
229BaseType_t xReturn = pdFAIL;
230
231 /* This function is called when the scheduler is started if
232 configUSE_TIMERS is set to 1. Check that the infrastructure used by the
233 timer service task has been created/initialised. If timers have already
234 been created then the initialisation will already have been performed. */
235 prvCheckForValidListAndQueue();
236
237 if( xTimerQueue != NULL )
238 {
239 #if( configSUPPORT_STATIC_ALLOCATION == 1 )
240 {
241 StaticTask_t *pxTimerTaskTCBBuffer = NULL;
242 StackType_t *pxTimerTaskStackBuffer = NULL;
243 uint32_t ulTimerTaskStackSize;
244
245 vApplicationGetTimerTaskMemory( &pxTimerTaskTCBBuffer, &pxTimerTaskStackBuffer, &ulTimerTaskStackSize );
246 xTimerTaskHandle = xTaskCreateStatic( prvTimerTask,
247 configTIMER_SERVICE_TASK_NAME,
248 ulTimerTaskStackSize,
249 NULL,
250 ( ( UBaseType_t ) configTIMER_TASK_PRIORITY ) | portPRIVILEGE_BIT,
251 pxTimerTaskStackBuffer,
252 pxTimerTaskTCBBuffer );
253
254 if( xTimerTaskHandle != NULL )
255 {
256 xReturn = pdPASS;
257 }
258 }
259 #else
260 {
261 xReturn = xTaskCreate( prvTimerTask,
262 configTIMER_SERVICE_TASK_NAME,
263 configTIMER_TASK_STACK_DEPTH,
264 NULL,
265 ( ( UBaseType_t ) configTIMER_TASK_PRIORITY ) | portPRIVILEGE_BIT,
266 &xTimerTaskHandle );
267 }
268 #endif /* configSUPPORT_STATIC_ALLOCATION */
269 }
270 else
271 {
272 mtCOVERAGE_TEST_MARKER();
273 }
274
275 configASSERT( xReturn );
276 return xReturn;
277}
278/*-----------------------------------------------------------*/
279
280#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
281
282 TimerHandle_t xTimerCreate( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
283 const TickType_t xTimerPeriodInTicks,
284 const UBaseType_t uxAutoReload,
285 void * const pvTimerID,
286 TimerCallbackFunction_t pxCallbackFunction )
287 {
288 Timer_t *pxNewTimer;
289
290 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 mame. */
291
292 if( pxNewTimer != NULL )
293 {
294 /* Status is thus far zero as the timer is not created statically
295 and has not been started. The auto-reload bit may get set in
296 prvInitialiseNewTimer. */
297 pxNewTimer->ucStatus = 0x00;
298 prvInitialiseNewTimer( pcTimerName, xTimerPeriodInTicks, uxAutoReload, pvTimerID, pxCallbackFunction, pxNewTimer );
299 }
300
301 return pxNewTimer;
302 }
303
304#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
305/*-----------------------------------------------------------*/
306
307#if( configSUPPORT_STATIC_ALLOCATION == 1 )
308
309 TimerHandle_t xTimerCreateStatic( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
310 const TickType_t xTimerPeriodInTicks,
311 const UBaseType_t uxAutoReload,
312 void * const pvTimerID,
313 TimerCallbackFunction_t pxCallbackFunction,
314 StaticTimer_t *pxTimerBuffer )
315 {
316 Timer_t *pxNewTimer;
317
318 #if( configASSERT_DEFINED == 1 )
319 {
320 /* Sanity check that the size of the structure used to declare a
321 variable of type StaticTimer_t equals the size of the real timer
322 structure. */
323 volatile size_t xSize = sizeof( StaticTimer_t );
324 configASSERT( xSize == sizeof( Timer_t ) );
325 ( void ) xSize; /* Keeps lint quiet when configASSERT() is not defined. */
326 }
327 #endif /* configASSERT_DEFINED */
328
329 /* A pointer to a StaticTimer_t structure MUST be provided, use it. */
330 configASSERT( pxTimerBuffer );
331 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. */
332
333 if( pxNewTimer != NULL )
334 {
335 /* Timers can be created statically or dynamically so note this
336 timer was created statically in case it is later deleted. The
337 auto-reload bit may get set in prvInitialiseNewTimer(). */
338 pxNewTimer->ucStatus = tmrSTATUS_IS_STATICALLY_ALLOCATED;
339
340 prvInitialiseNewTimer( pcTimerName, xTimerPeriodInTicks, uxAutoReload, pvTimerID, pxCallbackFunction, pxNewTimer );
341 }
342
343 return pxNewTimer;
344 }
345
346#endif /* configSUPPORT_STATIC_ALLOCATION */
347/*-----------------------------------------------------------*/
348
349static void prvInitialiseNewTimer( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
350 const TickType_t xTimerPeriodInTicks,
351 const UBaseType_t uxAutoReload,
352 void * const pvTimerID,
353 TimerCallbackFunction_t pxCallbackFunction,
354 Timer_t *pxNewTimer )
355{
356 /* 0 is not a valid value for xTimerPeriodInTicks. */
357 configASSERT( ( xTimerPeriodInTicks > 0 ) );
358
359 if( pxNewTimer != NULL )
360 {
361 /* Ensure the infrastructure used by the timer service task has been
362 created/initialised. */
363 prvCheckForValidListAndQueue();
364
365 /* Initialise the timer structure members using the function
366 parameters. */
367 pxNewTimer->pcTimerName = pcTimerName;
368 pxNewTimer->xTimerPeriodInTicks = xTimerPeriodInTicks;
369 pxNewTimer->pvTimerID = pvTimerID;
370 pxNewTimer->pxCallbackFunction = pxCallbackFunction;
371 vListInitialiseItem( &( pxNewTimer->xTimerListItem ) );
372 if( uxAutoReload != pdFALSE )
373 {
374 pxNewTimer->ucStatus |= tmrSTATUS_IS_AUTORELOAD;
375 }
376 traceTIMER_CREATE( pxNewTimer );
377 }
378}
379/*-----------------------------------------------------------*/
380
381BaseType_t xTimerGenericCommand( TimerHandle_t xTimer, const BaseType_t xCommandID, const TickType_t xOptionalValue, BaseType_t * const pxHigherPriorityTaskWoken, const TickType_t xTicksToWait )
382{
383BaseType_t xReturn = pdFAIL;
384DaemonTaskMessage_t xMessage;
385
386 configASSERT( xTimer );
387
388 /* Send a message to the timer service task to perform a particular action
389 on a particular timer definition. */
390 if( xTimerQueue != NULL )
391 {
392 /* Send a command to the timer service task to start the xTimer timer. */
393 xMessage.xMessageID = xCommandID;
394 xMessage.u.xTimerParameters.xMessageValue = xOptionalValue;
395 xMessage.u.xTimerParameters.pxTimer = xTimer;
396
397 if( xCommandID < tmrFIRST_FROM_ISR_COMMAND )
398 {
399 if( xTaskGetSchedulerState() == taskSCHEDULER_RUNNING )
400 {
401 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xTicksToWait );
402 }
403 else
404 {
405 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, tmrNO_DELAY );
406 }
407 }
408 else
409 {
410 xReturn = xQueueSendToBackFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
411 }
412
413 traceTIMER_COMMAND_SEND( xTimer, xCommandID, xOptionalValue, xReturn );
414 }
415 else
416 {
417 mtCOVERAGE_TEST_MARKER();
418 }
419
420 return xReturn;
421}
422/*-----------------------------------------------------------*/
423
424TaskHandle_t xTimerGetTimerDaemonTaskHandle( void )
425{
426 /* If xTimerGetTimerDaemonTaskHandle() is called before the scheduler has been
427 started, then xTimerTaskHandle will be NULL. */
428 configASSERT( ( xTimerTaskHandle != NULL ) );
429 return xTimerTaskHandle;
430}
431/*-----------------------------------------------------------*/
432
433TickType_t xTimerGetPeriod( TimerHandle_t xTimer )
434{
435Timer_t *pxTimer = xTimer;
436
437 configASSERT( xTimer );
438 return pxTimer->xTimerPeriodInTicks;
439}
440/*-----------------------------------------------------------*/
441
442void vTimerSetReloadMode( TimerHandle_t xTimer, const UBaseType_t uxAutoReload )
443{
444Timer_t * pxTimer = xTimer;
445
446 configASSERT( xTimer );
447 taskENTER_CRITICAL();
448 {
449 if( uxAutoReload != pdFALSE )
450 {
451 pxTimer->ucStatus |= tmrSTATUS_IS_AUTORELOAD;
452 }
453 else
454 {
455 pxTimer->ucStatus &= ~tmrSTATUS_IS_AUTORELOAD;
456 }
457 }
458 taskEXIT_CRITICAL();
459}
460/*-----------------------------------------------------------*/
461
462UBaseType_t uxTimerGetReloadMode( TimerHandle_t xTimer )
463{
464Timer_t * pxTimer = xTimer;
465UBaseType_t uxReturn;
466
467 configASSERT( xTimer );
468 taskENTER_CRITICAL();
469 {
470 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) == 0 )
471 {
472 /* Not an auto-reload timer. */
473 uxReturn = ( UBaseType_t ) pdFALSE;
474 }
475 else
476 {
477 /* Is an auto-reload timer. */
478 uxReturn = ( UBaseType_t ) pdTRUE;
479 }
480 }
481 taskEXIT_CRITICAL();
482
483 return uxReturn;
484}
485/*-----------------------------------------------------------*/
486
487TickType_t xTimerGetExpiryTime( TimerHandle_t xTimer )
488{
489Timer_t * pxTimer = xTimer;
490TickType_t xReturn;
491
492 configASSERT( xTimer );
493 xReturn = listGET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ) );
494 return xReturn;
495}
496/*-----------------------------------------------------------*/
497
498const char * pcTimerGetName( TimerHandle_t xTimer ) /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
499{
500Timer_t *pxTimer = xTimer;
501
502 configASSERT( xTimer );
503 return pxTimer->pcTimerName;
504}
505/*-----------------------------------------------------------*/
506
507static void prvProcessExpiredTimer( const TickType_t xNextExpireTime, const TickType_t xTimeNow )
508{
509BaseType_t xResult;
510Timer_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. */
511
512 /* Remove the timer from the list of active timers. A check has already
513 been performed to ensure the list is not empty. */
514 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
515 traceTIMER_EXPIRED( pxTimer );
516
517 /* If the timer is an auto-reload timer then calculate the next
518 expiry time and re-insert the timer in the list of active timers. */
519 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) != 0 )
520 {
521 /* The timer is inserted into a list using a time relative to anything
522 other than the current time. It will therefore be inserted into the
523 correct list relative to the time this task thinks it is now. */
524 if( prvInsertTimerInActiveList( pxTimer, ( xNextExpireTime + pxTimer->xTimerPeriodInTicks ), xTimeNow, xNextExpireTime ) != pdFALSE )
525 {
526 /* The timer expired before it was added to the active timer
527 list. Reload it now. */
528 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START_DONT_TRACE, xNextExpireTime, NULL, tmrNO_DELAY );
529 configASSERT( xResult );
530 ( void ) xResult;
531 }
532 else
533 {
534 mtCOVERAGE_TEST_MARKER();
535 }
536 }
537 else
538 {
539 pxTimer->ucStatus &= ~tmrSTATUS_IS_ACTIVE;
540 mtCOVERAGE_TEST_MARKER();
541 }
542
543 /* Call the timer callback. */
544 pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );
545}
546/*-----------------------------------------------------------*/
547
548static portTASK_FUNCTION( prvTimerTask, pvParameters )
549{
550TickType_t xNextExpireTime;
551BaseType_t xListWasEmpty;
552
553 /* Just to avoid compiler warnings. */
554 ( void ) pvParameters;
555
556 #if( configUSE_DAEMON_TASK_STARTUP_HOOK == 1 )
557 {
558 extern void vApplicationDaemonTaskStartupHook( void );
559
560 /* Allow the application writer to execute some code in the context of
561 this task at the point the task starts executing. This is useful if the
562 application includes initialisation code that would benefit from
563 executing after the scheduler has been started. */
564 vApplicationDaemonTaskStartupHook();
565 }
566 #endif /* configUSE_DAEMON_TASK_STARTUP_HOOK */
567
568 for( ;; )
569 {
570 /* Query the timers list to see if it contains any timers, and if so,
571 obtain the time at which the next timer will expire. */
572 xNextExpireTime = prvGetNextExpireTime( &xListWasEmpty );
573
574 /* If a timer has expired, process it. Otherwise, block this task
575 until either a timer does expire, or a command is received. */
576 prvProcessTimerOrBlockTask( xNextExpireTime, xListWasEmpty );
577
578 /* Empty the command queue. */
579 prvProcessReceivedCommands();
580 }
581}
582/*-----------------------------------------------------------*/
583
584static void prvProcessTimerOrBlockTask( const TickType_t xNextExpireTime, BaseType_t xListWasEmpty )
585{
586TickType_t xTimeNow;
587BaseType_t xTimerListsWereSwitched;
588
589 vTaskSuspendAll();
590 {
591 /* Obtain the time now to make an assessment as to whether the timer
592 has expired or not. If obtaining the time causes the lists to switch
593 then don't process this timer as any timers that remained in the list
594 when the lists were switched will have been processed within the
595 prvSampleTimeNow() function. */
596 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
597 if( xTimerListsWereSwitched == pdFALSE )
598 {
599 /* The tick count has not overflowed, has the timer expired? */
600 if( ( xListWasEmpty == pdFALSE ) && ( xNextExpireTime <= xTimeNow ) )
601 {
602 ( void ) xTaskResumeAll();
603 prvProcessExpiredTimer( xNextExpireTime, xTimeNow );
604 }
605 else
606 {
607 /* The tick count has not overflowed, and the next expire
608 time has not been reached yet. This task should therefore
609 block to wait for the next expire time or a command to be
610 received - whichever comes first. The following line cannot
611 be reached unless xNextExpireTime > xTimeNow, except in the
612 case when the current timer list is empty. */
613 if( xListWasEmpty != pdFALSE )
614 {
615 /* The current timer list is empty - is the overflow list
616 also empty? */
617 xListWasEmpty = listLIST_IS_EMPTY( pxOverflowTimerList );
618 }
619
620 vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ), xListWasEmpty );
621
622 if( xTaskResumeAll() == pdFALSE )
623 {
624 /* Yield to wait for either a command to arrive, or the
625 block time to expire. If a command arrived between the
626 critical section being exited and this yield then the yield
627 will not cause the task to block. */
628 portYIELD_WITHIN_API();
629 }
630 else
631 {
632 mtCOVERAGE_TEST_MARKER();
633 }
634 }
635 }
636 else
637 {
638 ( void ) xTaskResumeAll();
639 }
640 }
641}
642/*-----------------------------------------------------------*/
643
644static TickType_t prvGetNextExpireTime( BaseType_t * const pxListWasEmpty )
645{
646TickType_t xNextExpireTime;
647
648 /* Timers are listed in expiry time order, with the head of the list
649 referencing the task that will expire first. Obtain the time at which
650 the timer with the nearest expiry time will expire. If there are no
651 active timers then just set the next expire time to 0. That will cause
652 this task to unblock when the tick count overflows, at which point the
653 timer lists will be switched and the next expiry time can be
654 re-assessed. */
655 *pxListWasEmpty = listLIST_IS_EMPTY( pxCurrentTimerList );
656 if( *pxListWasEmpty == pdFALSE )
657 {
658 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
659 }
660 else
661 {
662 /* Ensure the task unblocks when the tick count rolls over. */
663 xNextExpireTime = ( TickType_t ) 0U;
664 }
665
666 return xNextExpireTime;
667}
668/*-----------------------------------------------------------*/
669
670static TickType_t prvSampleTimeNow( BaseType_t * const pxTimerListsWereSwitched )
671{
672TickType_t xTimeNow;
673PRIVILEGED_DATA static TickType_t xLastTime = ( TickType_t ) 0U; /*lint !e956 Variable is only accessible to one task. */
674
675 xTimeNow = xTaskGetTickCount();
676
677 if( xTimeNow < xLastTime )
678 {
679 prvSwitchTimerLists();
680 *pxTimerListsWereSwitched = pdTRUE;
681 }
682 else
683 {
684 *pxTimerListsWereSwitched = pdFALSE;
685 }
686
687 xLastTime = xTimeNow;
688
689 return xTimeNow;
690}
691/*-----------------------------------------------------------*/
692
693static BaseType_t prvInsertTimerInActiveList( Timer_t * const pxTimer, const TickType_t xNextExpiryTime, const TickType_t xTimeNow, const TickType_t xCommandTime )
694{
695BaseType_t xProcessTimerNow = pdFALSE;
696
697 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xNextExpiryTime );
698 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
699
700 if( xNextExpiryTime <= xTimeNow )
701 {
702 /* Has the expiry time elapsed between the command to start/reset a
703 timer was issued, and the time the command was processed? */
704 if( ( ( TickType_t ) ( xTimeNow - xCommandTime ) ) >= pxTimer->xTimerPeriodInTicks ) /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
705 {
706 /* The time between a command being issued and the command being
707 processed actually exceeds the timers period. */
708 xProcessTimerNow = pdTRUE;
709 }
710 else
711 {
712 vListInsert( pxOverflowTimerList, &( pxTimer->xTimerListItem ) );
713 }
714 }
715 else
716 {
717 if( ( xTimeNow < xCommandTime ) && ( xNextExpiryTime >= xCommandTime ) )
718 {
719 /* If, since the command was issued, the tick count has overflowed
720 but the expiry time has not, then the timer must have already passed
721 its expiry time and should be processed immediately. */
722 xProcessTimerNow = pdTRUE;
723 }
724 else
725 {
726 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
727 }
728 }
729
730 return xProcessTimerNow;
731}
732/*-----------------------------------------------------------*/
733
734static void prvProcessReceivedCommands( void )
735{
736DaemonTaskMessage_t xMessage;
737Timer_t *pxTimer;
738BaseType_t xTimerListsWereSwitched, xResult;
739TickType_t xTimeNow;
740
741 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. */
742 {
743 #if ( INCLUDE_xTimerPendFunctionCall == 1 )
744 {
745 /* Negative commands are pended function calls rather than timer
746 commands. */
747 if( xMessage.xMessageID < ( BaseType_t ) 0 )
748 {
749 const CallbackParameters_t * const pxCallback = &( xMessage.u.xCallbackParameters );
750
751 /* The timer uses the xCallbackParameters member to request a
752 callback be executed. Check the callback is not NULL. */
753 configASSERT( pxCallback );
754
755 /* Call the function. */
756 pxCallback->pxCallbackFunction( pxCallback->pvParameter1, pxCallback->ulParameter2 );
757 }
758 else
759 {
760 mtCOVERAGE_TEST_MARKER();
761 }
762 }
763 #endif /* INCLUDE_xTimerPendFunctionCall */
764
765 /* Commands that are positive are timer commands rather than pended
766 function calls. */
767 if( xMessage.xMessageID >= ( BaseType_t ) 0 )
768 {
769 /* The messages uses the xTimerParameters member to work on a
770 software timer. */
771 pxTimer = xMessage.u.xTimerParameters.pxTimer;
772
773 if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE ) /*lint !e961. The cast is only redundant when NULL is passed into the macro. */
774 {
775 /* The timer is in a list, remove it. */
776 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
777 }
778 else
779 {
780 mtCOVERAGE_TEST_MARKER();
781 }
782
783 traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.u.xTimerParameters.xMessageValue );
784
785 /* In this case the xTimerListsWereSwitched parameter is not used, but
786 it must be present in the function call. prvSampleTimeNow() must be
787 called after the message is received from xTimerQueue so there is no
788 possibility of a higher priority task adding a message to the message
789 queue with a time that is ahead of the timer daemon task (because it
790 pre-empted the timer daemon task after the xTimeNow value was set). */
791 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
792
793 switch( xMessage.xMessageID )
794 {
795 case tmrCOMMAND_START :
796 case tmrCOMMAND_START_FROM_ISR :
797 case tmrCOMMAND_RESET :
798 case tmrCOMMAND_RESET_FROM_ISR :
799 case tmrCOMMAND_START_DONT_TRACE :
800 /* Start or restart a timer. */
801 pxTimer->ucStatus |= tmrSTATUS_IS_ACTIVE;
802 if( prvInsertTimerInActiveList( pxTimer, xMessage.u.xTimerParameters.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.u.xTimerParameters.xMessageValue ) != pdFALSE )
803 {
804 /* The timer expired before it was added to the active
805 timer list. Process it now. */
806 pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );
807 traceTIMER_EXPIRED( pxTimer );
808
809 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) != 0 )
810 {
811 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START_DONT_TRACE, xMessage.u.xTimerParameters.xMessageValue + pxTimer->xTimerPeriodInTicks, NULL, tmrNO_DELAY );
812 configASSERT( xResult );
813 ( void ) xResult;
814 }
815 else
816 {
817 mtCOVERAGE_TEST_MARKER();
818 }
819 }
820 else
821 {
822 mtCOVERAGE_TEST_MARKER();
823 }
824 break;
825
826 case tmrCOMMAND_STOP :
827 case tmrCOMMAND_STOP_FROM_ISR :
828 /* The timer has already been removed from the active list. */
829 pxTimer->ucStatus &= ~tmrSTATUS_IS_ACTIVE;
830 break;
831
832 case tmrCOMMAND_CHANGE_PERIOD :
833 case tmrCOMMAND_CHANGE_PERIOD_FROM_ISR :
834 pxTimer->ucStatus |= tmrSTATUS_IS_ACTIVE;
835 pxTimer->xTimerPeriodInTicks = xMessage.u.xTimerParameters.xMessageValue;
836 configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );
837
838 /* The new period does not really have a reference, and can
839 be longer or shorter than the old one. The command time is
840 therefore set to the current time, and as the period cannot
841 be zero the next expiry time can only be in the future,
842 meaning (unlike for the xTimerStart() case above) there is
843 no fail case that needs to be handled here. */
844 ( void ) prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );
845 break;
846
847 case tmrCOMMAND_DELETE :
848 #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
849 {
850 /* The timer has already been removed from the active list,
851 just free up the memory if the memory was dynamically
852 allocated. */
853 if( ( pxTimer->ucStatus & tmrSTATUS_IS_STATICALLY_ALLOCATED ) == ( uint8_t ) 0 )
854 {
855 vPortFree( pxTimer );
856 }
857 else
858 {
859 pxTimer->ucStatus &= ~tmrSTATUS_IS_ACTIVE;
860 }
861 }
862 #else
863 {
864 /* If dynamic allocation is not enabled, the memory
865 could not have been dynamically allocated. So there is
866 no need to free the memory - just mark the timer as
867 "not active". */
868 pxTimer->ucStatus &= ~tmrSTATUS_IS_ACTIVE;
869 }
870 #endif /* configSUPPORT_DYNAMIC_ALLOCATION */
871 break;
872
873 default :
874 /* Don't expect to get here. */
875 break;
876 }
877 }
878 }
879}
880/*-----------------------------------------------------------*/
881
882static void prvSwitchTimerLists( void )
883{
884TickType_t xNextExpireTime, xReloadTime;
885List_t *pxTemp;
886Timer_t *pxTimer;
887BaseType_t xResult;
888
889 /* The tick count has overflowed. The timer lists must be switched.
890 If there are any timers still referenced from the current timer list
891 then they must have expired and should be processed before the lists
892 are switched. */
893 while( listLIST_IS_EMPTY( pxCurrentTimerList ) == pdFALSE )
894 {
895 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
896
897 /* Remove the timer from the list. */
898 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. */
899 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
900 traceTIMER_EXPIRED( pxTimer );
901
902 /* Execute its callback, then send a command to restart the timer if
903 it is an auto-reload timer. It cannot be restarted here as the lists
904 have not yet been switched. */
905 pxTimer->pxCallbackFunction( ( TimerHandle_t ) pxTimer );
906
907 if( ( pxTimer->ucStatus & tmrSTATUS_IS_AUTORELOAD ) != 0 )
908 {
909 /* Calculate the reload value, and if the reload value results in
910 the timer going into the same timer list then it has already expired
911 and the timer should be re-inserted into the current list so it is
912 processed again within this loop. Otherwise a command should be sent
913 to restart the timer to ensure it is only inserted into a list after
914 the lists have been swapped. */
915 xReloadTime = ( xNextExpireTime + pxTimer->xTimerPeriodInTicks );
916 if( xReloadTime > xNextExpireTime )
917 {
918 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xReloadTime );
919 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
920 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
921 }
922 else
923 {
924 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START_DONT_TRACE, xNextExpireTime, NULL, tmrNO_DELAY );
925 configASSERT( xResult );
926 ( void ) xResult;
927 }
928 }
929 else
930 {
931 mtCOVERAGE_TEST_MARKER();
932 }
933 }
934
935 pxTemp = pxCurrentTimerList;
936 pxCurrentTimerList = pxOverflowTimerList;
937 pxOverflowTimerList = pxTemp;
938}
939/*-----------------------------------------------------------*/
940
941static void prvCheckForValidListAndQueue( void )
942{
943 /* Check that the list from which active timers are referenced, and the
944 queue used to communicate with the timer service, have been
945 initialised. */
946 taskENTER_CRITICAL();
947 {
948 if( xTimerQueue == NULL )
949 {
950 vListInitialise( &xActiveTimerList1 );
951 vListInitialise( &xActiveTimerList2 );
952 pxCurrentTimerList = &xActiveTimerList1;
953 pxOverflowTimerList = &xActiveTimerList2;
954
955 #if( configSUPPORT_STATIC_ALLOCATION == 1 )
956 {
957 /* The timer queue is allocated statically in case
958 configSUPPORT_DYNAMIC_ALLOCATION is 0. */
959 static StaticQueue_t xStaticTimerQueue; /*lint !e956 Ok to declare in this manner to prevent additional conditional compilation guards in other locations. */
960 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. */
961
962 xTimerQueue = xQueueCreateStatic( ( UBaseType_t ) configTIMER_QUEUE_LENGTH, ( UBaseType_t ) sizeof( DaemonTaskMessage_t ), &( ucStaticTimerQueueStorage[ 0 ] ), &xStaticTimerQueue );
963 }
964 #else
965 {
966 xTimerQueue = xQueueCreate( ( UBaseType_t ) configTIMER_QUEUE_LENGTH, sizeof( DaemonTaskMessage_t ) );
967 }
968 #endif
969
970 #if ( configQUEUE_REGISTRY_SIZE > 0 )
971 {
972 if( xTimerQueue != NULL )
973 {
974 vQueueAddToRegistry( xTimerQueue, "TmrQ" );
975 }
976 else
977 {
978 mtCOVERAGE_TEST_MARKER();
979 }
980 }
981 #endif /* configQUEUE_REGISTRY_SIZE */
982 }
983 else
984 {
985 mtCOVERAGE_TEST_MARKER();
986 }
987 }
988 taskEXIT_CRITICAL();
989}
990/*-----------------------------------------------------------*/
991
992BaseType_t xTimerIsTimerActive( TimerHandle_t xTimer )
993{
994BaseType_t xReturn;
995Timer_t *pxTimer = xTimer;
996
997 configASSERT( xTimer );
998
999 /* Is the timer in the list of active timers? */
1000 taskENTER_CRITICAL();
1001 {
1002 if( ( pxTimer->ucStatus & tmrSTATUS_IS_ACTIVE ) == 0 )
1003 {
1004 xReturn = pdFALSE;
1005 }
1006 else
1007 {
1008 xReturn = pdTRUE;
1009 }
1010 }
1011 taskEXIT_CRITICAL();
1012
1013 return xReturn;
1014} /*lint !e818 Can't be pointer to const due to the typedef. */
1015/*-----------------------------------------------------------*/
1016
1017void *pvTimerGetTimerID( const TimerHandle_t xTimer )
1018{
1019Timer_t * const pxTimer = xTimer;
1020void *pvReturn;
1021
1022 configASSERT( xTimer );
1023
1024 taskENTER_CRITICAL();
1025 {
1026 pvReturn = pxTimer->pvTimerID;
1027 }
1028 taskEXIT_CRITICAL();
1029
1030 return pvReturn;
1031}
1032/*-----------------------------------------------------------*/
1033
1034void vTimerSetTimerID( TimerHandle_t xTimer, void *pvNewID )
1035{
1036Timer_t * const pxTimer = xTimer;
1037
1038 configASSERT( xTimer );
1039
1040 taskENTER_CRITICAL();
1041 {
1042 pxTimer->pvTimerID = pvNewID;
1043 }
1044 taskEXIT_CRITICAL();
1045}
1046/*-----------------------------------------------------------*/
1047
1048#if( INCLUDE_xTimerPendFunctionCall == 1 )
1049
1050 BaseType_t xTimerPendFunctionCallFromISR( PendedFunction_t xFunctionToPend, void *pvParameter1, uint32_t ulParameter2, BaseType_t *pxHigherPriorityTaskWoken )
1051 {
1052 DaemonTaskMessage_t xMessage;
1053 BaseType_t xReturn;
1054
1055 /* Complete the message with the function parameters and post it to the
1056 daemon task. */
1057 xMessage.xMessageID = tmrCOMMAND_EXECUTE_CALLBACK_FROM_ISR;
1058 xMessage.u.xCallbackParameters.pxCallbackFunction = xFunctionToPend;
1059 xMessage.u.xCallbackParameters.pvParameter1 = pvParameter1;
1060 xMessage.u.xCallbackParameters.ulParameter2 = ulParameter2;
1061
1062 xReturn = xQueueSendFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
1063
1064 tracePEND_FUNC_CALL_FROM_ISR( xFunctionToPend, pvParameter1, ulParameter2, xReturn );
1065
1066 return xReturn;
1067 }
1068
1069#endif /* INCLUDE_xTimerPendFunctionCall */
1070/*-----------------------------------------------------------*/
1071
1072#if( INCLUDE_xTimerPendFunctionCall == 1 )
1073
1074 BaseType_t xTimerPendFunctionCall( PendedFunction_t xFunctionToPend, void *pvParameter1, uint32_t ulParameter2, TickType_t xTicksToWait )
1075 {
1076 DaemonTaskMessage_t xMessage;
1077 BaseType_t xReturn;
1078
1079 /* This function can only be called after a timer has been created or
1080 after the scheduler has been started because, until then, the timer
1081 queue does not exist. */
1082 configASSERT( xTimerQueue );
1083
1084 /* Complete the message with the function parameters and post it to the
1085 daemon task. */
1086 xMessage.xMessageID = tmrCOMMAND_EXECUTE_CALLBACK;
1087 xMessage.u.xCallbackParameters.pxCallbackFunction = xFunctionToPend;
1088 xMessage.u.xCallbackParameters.pvParameter1 = pvParameter1;
1089 xMessage.u.xCallbackParameters.ulParameter2 = ulParameter2;
1090
1091 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xTicksToWait );
1092
1093 tracePEND_FUNC_CALL( xFunctionToPend, pvParameter1, ulParameter2, xReturn );
1094
1095 return xReturn;
1096 }
1097
1098#endif /* INCLUDE_xTimerPendFunctionCall */
1099/*-----------------------------------------------------------*/
1100
1101#if ( configUSE_TRACE_FACILITY == 1 )
1102
1103 UBaseType_t uxTimerGetTimerNumber( TimerHandle_t xTimer )
1104 {
1105 return ( ( Timer_t * ) xTimer )->uxTimerNumber;
1106 }
1107
1108#endif /* configUSE_TRACE_FACILITY */
1109/*-----------------------------------------------------------*/
1110
1111#if ( configUSE_TRACE_FACILITY == 1 )
1112
1113 void vTimerSetTimerNumber( TimerHandle_t xTimer, UBaseType_t uxTimerNumber )
1114 {
1115 ( ( Timer_t * ) xTimer )->uxTimerNumber = uxTimerNumber;
1116 }
1117
1118#endif /* configUSE_TRACE_FACILITY */
1119/*-----------------------------------------------------------*/
1120
1121/* This entire source file will be skipped if the application is not configured
1122to include software timer functionality. If you want to include software timer
1123functionality then ensure configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
1124#endif /* configUSE_TIMERS == 1 */
1125
1126
1127
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