-/* Need a method of switching to an overflow list. _RB_*/\r
-\r
/*\r
- FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.\r
+ FreeRTOS V7.1.0 - Copyright (C) 2011 Real Time Engineers Ltd.\r
+\r
\r
***************************************************************************\r
- * *\r
- * If you are: *\r
- * *\r
- * + New to FreeRTOS, *\r
- * + Wanting to learn FreeRTOS or multitasking in general quickly *\r
- * + Looking for basic training, *\r
- * + Wanting to improve your FreeRTOS skills and productivity *\r
- * *\r
- * then take a look at the FreeRTOS books - available as PDF or paperback *\r
- * *\r
- * "Using the FreeRTOS Real Time Kernel - a Practical Guide" *\r
- * http://www.FreeRTOS.org/Documentation *\r
- * *\r
- * A pdf reference manual is also available. Both are usually delivered *\r
- * to your inbox within 20 minutes to two hours when purchased between 8am *\r
- * and 8pm GMT (although please allow up to 24 hours in case of *\r
- * exceptional circumstances). Thank you for your support! *\r
- * *\r
+ * *\r
+ * FreeRTOS tutorial books are available in pdf and paperback. *\r
+ * Complete, revised, and edited pdf reference manuals are also *\r
+ * available. *\r
+ * *\r
+ * Purchasing FreeRTOS documentation will not only help you, by *\r
+ * ensuring you get running as quickly as possible and with an *\r
+ * in-depth knowledge of how to use FreeRTOS, it will also help *\r
+ * the FreeRTOS project to continue with its mission of providing *\r
+ * professional grade, cross platform, de facto standard solutions *\r
+ * for microcontrollers - completely free of charge! *\r
+ * *\r
+ * >>> See http://www.FreeRTOS.org/Documentation for details. <<< *\r
+ * *\r
+ * Thank you for using FreeRTOS, and thank you for your support! *\r
+ * *\r
***************************************************************************\r
\r
+\r
This file is part of the FreeRTOS distribution.\r
\r
FreeRTOS is free software; you can redistribute it and/or modify it under\r
the terms of the GNU General Public License (version 2) as published by the\r
Free Software Foundation AND MODIFIED BY the FreeRTOS exception.\r
- ***NOTE*** The exception to the GPL is included to allow you to distribute\r
- a combined work that includes FreeRTOS without being obliged to provide the\r
- source code for proprietary components outside of the FreeRTOS kernel.\r
- FreeRTOS is distributed in the hope that it will be useful, but WITHOUT\r
- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or\r
- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for\r
+ >>>NOTE<<< The modification to the GPL is included to allow you to\r
+ distribute a combined work that includes FreeRTOS without being obliged to\r
+ provide the source code for proprietary components outside of the FreeRTOS\r
+ kernel. FreeRTOS is distributed in the hope that it will be useful, but\r
+ WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY\r
+ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for\r
more details. You should have received a copy of the GNU General Public\r
License and the FreeRTOS license exception along with FreeRTOS; if not it\r
can be viewed here: http://www.freertos.org/a00114.html and also obtained\r
\r
#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE\r
\r
+/* This entire source file will be skipped if the application is not configured\r
+to include software timer functionality. This #if is closed at the very bottom\r
+of this file. If you want to include software timer functionality then ensure\r
+configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */\r
+#if ( configUSE_TIMERS == 1 )\r
+\r
/* Misc definitions. */\r
#define tmrNO_DELAY ( portTickType ) 0U\r
\r
tmrTIMER_CALLBACK pxCallbackFunction; /*<< The function that will be called when the timer expires. */\r
} xTIMER;\r
\r
-/* The definition of messages that can be sent and received on the timer \r
+/* The definition of messages that can be sent and received on the timer\r
queue. */\r
typedef struct tmrTimerQueueMessage\r
{\r
portBASE_TYPE xMessageID; /*<< The command being sent to the timer service task. */\r
- portTickType xMessageValue; /*<< An optional value used by a subset of commands, for example, when chaning the period of a timer. */\r
+ portTickType xMessageValue; /*<< An optional value used by a subset of commands, for example, when changing the period of a timer. */\r
xTIMER * pxTimer; /*<< The timer to which the command will be applied. */\r
} xTIMER_MESSAGE;\r
\r
/* The list in which active timers are stored. Timers are referenced in expire\r
time order, with the nearest expiry time at the front of the list. Only the\r
timer service task is allowed to access xActiveTimerList. */\r
-PRIVILEGED_DATA static xList xActiveTimerList;\r
+PRIVILEGED_DATA static xList xActiveTimerList1;\r
+PRIVILEGED_DATA static xList xActiveTimerList2;\r
+PRIVILEGED_DATA static xList *pxCurrentTimerList;\r
+PRIVILEGED_DATA static xList *pxOverflowTimerList;\r
\r
/* A queue that is used to send commands to the timer service task. */\r
PRIVILEGED_DATA static xQueueHandle xTimerQueue = NULL;\r
\r
+#if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )\r
+ \r
+ PRIVILEGED_DATA static xTaskHandle xTimerTaskHandle = NULL;\r
+ \r
+#endif\r
+\r
/*-----------------------------------------------------------*/\r
\r
-/* \r
- * Initialise the infrustructure used by the timer service task if it has not\r
+/*\r
+ * Initialise the infrastructure used by the timer service task if it has not\r
* been initialised already.\r
*/\r
static void prvCheckForValidListAndQueue( void ) PRIVILEGED_FUNCTION;\r
\r
/*\r
* The timer service task (daemon). Timer functionality is controlled by this\r
- * task. Other tasks communicate with the timer service task using the \r
+ * task. Other tasks communicate with the timer service task using the\r
* xTimerQueue queue.\r
*/\r
static void prvTimerTask( void *pvParameters ) PRIVILEGED_FUNCTION;\r
\r
-/* \r
- * The following functions handle the commands that are sent to the timer\r
- * service task via the xTimerQueue queue.\r
- */\r
-static void prvTimerStart( xTIMER *pxTimer ) PRIVILEGED_FUNCTION;\r
-\r
/*\r
* Called by the timer service task to interpret and process a command it\r
- * received on the timer queue. \r
+ * received on the timer queue.\r
*/\r
static void prvProcessReceivedCommands( void ) PRIVILEGED_FUNCTION;\r
\r
+/*\r
+ * Insert the timer into either xActiveTimerList1, or xActiveTimerList2,\r
+ * depending on if the expire time causes a timer counter overflow.\r
+ */\r
+static portBASE_TYPE prvInsertTimerInActiveList( xTIMER *pxTimer, portTickType xNextExpiryTime, portTickType xTimeNow, portTickType xCommandTime ) PRIVILEGED_FUNCTION;\r
+\r
+/*\r
+ * An active timer has reached its expire time. Reload the timer if it is an\r
+ * auto reload timer, then call its callback.\r
+ */\r
+static void prvProcessExpiredTimer( portTickType xNextExpireTime, portTickType xTimeNow ) PRIVILEGED_FUNCTION;\r
+\r
+/*\r
+ * The tick count has overflowed. Switch the timer lists after ensuring the\r
+ * current timer list does not still reference some timers.\r
+ */\r
+static void prvSwitchTimerLists( portTickType xLastTime ) PRIVILEGED_FUNCTION;\r
+\r
+/*\r
+ * Obtain the current tick count, setting *pxTimerListsWereSwitched to pdTRUE\r
+ * if a tick count overflow occurred since prvSampleTimeNow() was last called.\r
+ */\r
+static portTickType prvSampleTimeNow( portBASE_TYPE *pxTimerListsWereSwitched ) PRIVILEGED_FUNCTION;\r
+\r
+/*\r
+ * If the timer list contains any active timers then return the expire time of\r
+ * the timer that will expire first and set *pxListWasEmpty to false. If the\r
+ * timer list does not contain any timers then return 0 and set *pxListWasEmpty\r
+ * to pdTRUE.\r
+ */\r
+static portTickType prvGetNextExpireTime( portBASE_TYPE *pxListWasEmpty ) PRIVILEGED_FUNCTION;\r
+\r
+/*\r
+ * If a timer has expired, process it. Otherwise, block the timer service task\r
+ * until either a timer does expire or a command is received.\r
+ */\r
+static void prvProcessTimerOrBlockTask( portTickType xNextExpireTime, portBASE_TYPE xListWasEmpty ) PRIVILEGED_FUNCTION;\r
+\r
/*-----------------------------------------------------------*/\r
\r
portBASE_TYPE xTimerCreateTimerTask( void )\r
{\r
portBASE_TYPE xReturn = pdFAIL;\r
\r
- /* This function is called when the scheduler is started if \r
- configUSE_TIMERS is set to 1. Check that the infrustructure used by the\r
+ /* This function is called when the scheduler is started if\r
+ configUSE_TIMERS is set to 1. Check that the infrastructure used by the\r
timer service task has been created/initialised. If timers have already\r
been created then the initialisation will already have been performed. */\r
prvCheckForValidListAndQueue();\r
\r
if( xTimerQueue != NULL )\r
{\r
- xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Timers", configTIMER_TASK_STACK_DEPTH, NULL, configTIMER_TASK_PRIORITY, NULL );\r
+ #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )\r
+ {\r
+ /* Create the timer task, storing its handle in xTimerTaskHandle so\r
+ it can be returned by the xTimerGetTimerDaemonTaskHandle() function. */\r
+ xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Tmr Svc", ( unsigned short ) configTIMER_TASK_STACK_DEPTH, NULL, ( unsigned portBASE_TYPE ) configTIMER_TASK_PRIORITY, &xTimerTaskHandle ); \r
+ }\r
+ #else\r
+ {\r
+ /* Create the timer task without storing its handle. */\r
+ xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Tmr Svc", ( unsigned short ) configTIMER_TASK_STACK_DEPTH, NULL, ( unsigned portBASE_TYPE ) configTIMER_TASK_PRIORITY, NULL);\r
+ }\r
+ #endif\r
}\r
\r
+ configASSERT( xReturn );\r
return xReturn;\r
}\r
/*-----------------------------------------------------------*/\r
xTIMER *pxNewTimer;\r
\r
/* Allocate the timer structure. */\r
- pxNewTimer = ( xTIMER * ) pvPortMalloc( sizeof( xTIMER ) );\r
- if( pxNewTimer != NULL )\r
+ if( xTimerPeriodInTicks == ( portTickType ) 0U )\r
{\r
- /* Ensure the infrustructure used by the timer service task has been\r
- created/initialised. */\r
- prvCheckForValidListAndQueue();\r
-\r
- /* Initialise the timer structure members using the function parameters. */\r
- pxNewTimer->pcTimerName = pcTimerName;\r
- pxNewTimer->xTimerPeriodInTicks = xTimerPeriodInTicks;\r
- pxNewTimer->uxAutoReload = uxAutoReload;\r
- pxNewTimer->pvTimerID = pvTimerID;\r
- pxNewTimer->pxCallbackFunction = pxCallbackFunction;\r
- vListInitialiseItem( &( pxNewTimer->xTimerListItem ) );\r
+ pxNewTimer = NULL;\r
+ configASSERT( ( xTimerPeriodInTicks > 0 ) );\r
}\r
-\r
+ else\r
+ {\r
+ pxNewTimer = ( xTIMER * ) pvPortMalloc( sizeof( xTIMER ) );\r
+ if( pxNewTimer != NULL )\r
+ {\r
+ /* Ensure the infrastructure used by the timer service task has been\r
+ created/initialised. */\r
+ prvCheckForValidListAndQueue();\r
+ \r
+ /* Initialise the timer structure members using the function parameters. */\r
+ pxNewTimer->pcTimerName = pcTimerName;\r
+ pxNewTimer->xTimerPeriodInTicks = xTimerPeriodInTicks;\r
+ pxNewTimer->uxAutoReload = uxAutoReload;\r
+ pxNewTimer->pvTimerID = pvTimerID;\r
+ pxNewTimer->pxCallbackFunction = pxCallbackFunction;\r
+ vListInitialiseItem( &( pxNewTimer->xTimerListItem ) );\r
+ \r
+ traceTIMER_CREATE( pxNewTimer );\r
+ }\r
+ else\r
+ {\r
+ traceTIMER_CREATE_FAILED();\r
+ }\r
+ }\r
+ \r
return ( xTimerHandle ) pxNewTimer;\r
}\r
/*-----------------------------------------------------------*/\r
\r
-portBASE_TYPE xTimerGenericCommand( xTimerHandle xTimer, portBASE_TYPE xCommandID, portTickType xOptionalValue, portTickType xBlockTime )\r
+portBASE_TYPE xTimerGenericCommand( xTimerHandle xTimer, portBASE_TYPE xCommandID, portTickType xOptionalValue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portTickType xBlockTime )\r
{\r
portBASE_TYPE xReturn = pdFAIL;\r
xTIMER_MESSAGE xMessage;\r
xMessage.xMessageValue = xOptionalValue;\r
xMessage.pxTimer = ( xTIMER * ) xTimer;\r
\r
- if( xTaskGetSchedulerState() == taskSCHEDULER_RUNNING )\r
+ if( pxHigherPriorityTaskWoken == NULL )\r
{\r
- xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xBlockTime );\r
+ if( xTaskGetSchedulerState() == taskSCHEDULER_RUNNING )\r
+ {\r
+ xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xBlockTime );\r
+ }\r
+ else\r
+ {\r
+ xReturn = xQueueSendToBack( xTimerQueue, &xMessage, tmrNO_DELAY );\r
+ }\r
}\r
else\r
{\r
- xReturn = xQueueSendToBack( xTimerQueue, &xMessage, tmrNO_DELAY );\r
+ xReturn = xQueueSendToBackFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );\r
}\r
+ \r
+ traceTIMER_COMMAND_SEND( xTimer, xCommandID, xOptionalValue, xReturn );\r
}\r
-\r
+ \r
return xReturn;\r
}\r
/*-----------------------------------------------------------*/\r
\r
-static void prvTimerTask( void *pvParameters )\r
+#if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )\r
+\r
+ xTaskHandle xTimerGetTimerDaemonTaskHandle( void )\r
+ {\r
+ /* If xTimerGetTimerDaemonTaskHandle() is called before the scheduler has been\r
+ started, then xTimerTaskHandle will be NULL. */\r
+ configASSERT( ( xTimerTaskHandle != NULL ) );\r
+ return xTimerTaskHandle;\r
+ }\r
+ \r
+#endif\r
+/*-----------------------------------------------------------*/\r
+\r
+static void prvProcessExpiredTimer( portTickType xNextExpireTime, portTickType xTimeNow )\r
{\r
-portTickType xNextExpireTime, xTimeNow;\r
xTIMER *pxTimer;\r
+portBASE_TYPE xResult;\r
+\r
+ /* Remove the timer from the list of active timers. A check has already\r
+ been performed to ensure the list is not empty. */\r
+ pxTimer = ( xTIMER * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );\r
+ vListRemove( &( pxTimer->xTimerListItem ) );\r
+ traceTIMER_EXPIRED( pxTimer );\r
+\r
+ /* If the timer is an auto reload timer then calculate the next\r
+ expiry time and re-insert the timer in the list of active timers. */\r
+ if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )\r
+ {\r
+ /* This is the only time a timer is inserted into a list using\r
+ a time relative to anything other than the current time. It\r
+ will therefore be inserted into the correct list relative to\r
+ the time this task thinks it is now, even if a command to\r
+ switch lists due to a tick count overflow is already waiting in\r
+ the timer queue. */\r
+ if( prvInsertTimerInActiveList( pxTimer, ( xNextExpireTime + pxTimer->xTimerPeriodInTicks ), xTimeNow, xNextExpireTime ) == pdTRUE )\r
+ {\r
+ /* The timer expired before it was added to the active timer\r
+ list. Reload it now. */\r
+ xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xNextExpireTime, NULL, tmrNO_DELAY );\r
+ configASSERT( xResult );\r
+ ( void ) xResult;\r
+ }\r
+ }\r
+\r
+ /* Call the timer callback. */\r
+ pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
+static void prvTimerTask( void *pvParameters )\r
+{\r
+portTickType xNextExpireTime;\r
+portBASE_TYPE xListWasEmpty;\r
\r
/* Just to avoid compiler warnings. */\r
( void ) pvParameters;\r
\r
for( ;; )\r
{\r
- /* Timers are listed in expiry time order, with the head of the list\r
- referencing the task that will expire first. Obtain the time at which\r
- the timer with the nearest expiry time will expire. If there are no\r
- active timers then just set the next expire time to the maximum possible\r
- time to ensure this task does not run unnecessarily. */\r
- if( listLIST_IS_EMPTY( &xActiveTimerList ) == pdFALSE )\r
+ /* Query the timers list to see if it contains any timers, and if so,\r
+ obtain the time at which the next timer will expire. */\r
+ xNextExpireTime = prvGetNextExpireTime( &xListWasEmpty );\r
+\r
+ /* If a timer has expired, process it. Otherwise, block this task\r
+ until either a timer does expire, or a command is received. */\r
+ prvProcessTimerOrBlockTask( xNextExpireTime, xListWasEmpty );\r
+ \r
+ /* Empty the command queue. */\r
+ prvProcessReceivedCommands(); \r
+ }\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
+static void prvProcessTimerOrBlockTask( portTickType xNextExpireTime, portBASE_TYPE xListWasEmpty )\r
+{\r
+portTickType xTimeNow;\r
+portBASE_TYPE xTimerListsWereSwitched;\r
+\r
+ vTaskSuspendAll();\r
+ {\r
+ /* Obtain the time now to make an assessment as to whether the timer\r
+ has expired or not. If obtaining the time causes the lists to switch\r
+ then don't process this timer as any timers that remained in the list\r
+ when the lists were switched will have been processed within the\r
+ prvSampelTimeNow() function. */\r
+ xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );\r
+ if( xTimerListsWereSwitched == pdFALSE )\r
{\r
- xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( &xActiveTimerList );\r
+ /* The tick count has not overflowed, has the timer expired? */\r
+ if( ( xListWasEmpty == pdFALSE ) && ( xNextExpireTime <= xTimeNow ) )\r
+ {\r
+ xTaskResumeAll();\r
+ prvProcessExpiredTimer( xNextExpireTime, xTimeNow );\r
+ }\r
+ else\r
+ {\r
+ /* The tick count has not overflowed, and the next expire\r
+ time has not been reached yet. This task should therefore\r
+ block to wait for the next expire time or a command to be\r
+ received - whichever comes first. The following line cannot\r
+ be reached unless xNextExpireTime > xTimeNow, except in the\r
+ case when the current timer list is empty. */\r
+ vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ) );\r
+\r
+ if( xTaskResumeAll() == pdFALSE )\r
+ {\r
+ /* Yield to wait for either a command to arrive, or the block time\r
+ to expire. If a command arrived between the critical section being\r
+ exited and this yield then the yield will not cause the task\r
+ to block. */\r
+ portYIELD_WITHIN_API();\r
+ }\r
+ }\r
}\r
else\r
{\r
- xNextExpireTime = portMAX_DELAY;\r
+ xTaskResumeAll();\r
}\r
+ }\r
+}\r
+/*-----------------------------------------------------------*/\r
\r
- /* Has the timer expired? */\r
- if( xNextExpireTime <= xTaskGetTickCount() )\r
- {\r
- /* Remove the timer from the list of active timers. */\r
- pxTimer = listGET_OWNER_OF_HEAD_ENTRY( &xActiveTimerList );\r
- vListRemove( &( pxTimer->xTimerListItem ) );\r
+static portTickType prvGetNextExpireTime( portBASE_TYPE *pxListWasEmpty )\r
+{\r
+portTickType xNextExpireTime;\r
+\r
+ /* Timers are listed in expiry time order, with the head of the list\r
+ referencing the task that will expire first. Obtain the time at which\r
+ the timer with the nearest expiry time will expire. If there are no\r
+ active timers then just set the next expire time to 0. That will cause\r
+ this task to unblock when the tick count overflows, at which point the\r
+ timer lists will be switched and the next expiry time can be\r
+ re-assessed. */\r
+ *pxListWasEmpty = listLIST_IS_EMPTY( pxCurrentTimerList );\r
+ if( *pxListWasEmpty == pdFALSE )\r
+ {\r
+ xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );\r
+ }\r
+ else\r
+ {\r
+ /* Ensure the task unblocks when the tick count rolls over. */\r
+ xNextExpireTime = ( portTickType ) 0U;\r
+ }\r
\r
- /* If the timer is an autoreload timer then calculate the next\r
- expiry time and re-insert the timer in the list of active timers. */\r
- if( pxTimer->uxAutoReload == pdTRUE )\r
- {\r
- listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), ( xNextExpireTime + pxTimer->xTimerPeriodInTicks ) );\r
- vListInsert( &xActiveTimerList, &( pxTimer->xTimerListItem ) );\r
- }\r
+ return xNextExpireTime;\r
+}\r
+/*-----------------------------------------------------------*/\r
\r
- /* Call the timer callback. */\r
- pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );\r
+static portTickType prvSampleTimeNow( portBASE_TYPE *pxTimerListsWereSwitched )\r
+{\r
+portTickType xTimeNow;\r
+static portTickType xLastTime = ( portTickType ) 0U;\r
+\r
+ xTimeNow = xTaskGetTickCount();\r
+ \r
+ if( xTimeNow < xLastTime )\r
+ {\r
+ prvSwitchTimerLists( xLastTime );\r
+ *pxTimerListsWereSwitched = pdTRUE;\r
+ }\r
+ else\r
+ {\r
+ *pxTimerListsWereSwitched = pdFALSE;\r
+ }\r
+ \r
+ xLastTime = xTimeNow;\r
+ \r
+ return xTimeNow;\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
+static portBASE_TYPE prvInsertTimerInActiveList( xTIMER *pxTimer, portTickType xNextExpiryTime, portTickType xTimeNow, portTickType xCommandTime )\r
+{\r
+portBASE_TYPE xProcessTimerNow = pdFALSE;\r
+\r
+ listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xNextExpiryTime );\r
+ listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );\r
+ \r
+ if( xNextExpiryTime <= xTimeNow )\r
+ {\r
+ /* Has the expiry time elapsed between the command to start/reset a\r
+ timer was issued, and the time the command was processed? */\r
+ if( ( ( portTickType ) ( xTimeNow - xCommandTime ) ) >= pxTimer->xTimerPeriodInTicks )\r
+ {\r
+ /* The time between a command being issued and the command being\r
+ processed actually exceeds the timers period. */\r
+ xProcessTimerNow = pdTRUE;\r
}\r
else\r
{\r
- /* Block this task until the next timer expires, or a command is\r
- received. */\r
- taskENTER_CRITICAL();\r
- {\r
- xTimeNow = xTaskGetTickCount();\r
- if( xTimeNow < xNextExpireTime )\r
- {\r
- /* This is a simple fast function - a yield will not be \r
- performed until after this critical section exits. */\r
- vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ) );\r
- }\r
- }\r
- taskEXIT_CRITICAL();\r
-\r
- /* Yield to wait for either a command to arrive, or the block time \r
- to expire. If a command arrived between the critical section being \r
- exited and this yeild then the yield will just return to the same\r
- task. */\r
- portYIELD_WITHIN_API();\r
-\r
- /* Empty the command queue, if it contains any commands. */\r
- prvProcessReceivedCommands();\r
+ vListInsert( pxOverflowTimerList, &( pxTimer->xTimerListItem ) );\r
}\r
}\r
+ else\r
+ {\r
+ if( ( xTimeNow < xCommandTime ) && ( xNextExpiryTime >= xCommandTime ) )\r
+ {\r
+ /* If, since the command was issued, the tick count has overflowed\r
+ but the expiry time has not, then the timer must have already passed\r
+ its expiry time and should be processed immediately. */\r
+ xProcessTimerNow = pdTRUE;\r
+ }\r
+ else\r
+ {\r
+ vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );\r
+ }\r
+ }\r
+\r
+ return xProcessTimerNow;\r
}\r
/*-----------------------------------------------------------*/\r
\r
static void prvProcessReceivedCommands( void )\r
{\r
xTIMER_MESSAGE xMessage;\r
-portTickType xTimeToExpire;\r
xTIMER *pxTimer;\r
+portBASE_TYPE xTimerListsWereSwitched, xResult;\r
+portTickType xTimeNow;\r
+\r
+ /* In this case the xTimerListsWereSwitched parameter is not used, but it\r
+ must be present in the function call. */\r
+ xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );\r
\r
while( xQueueReceive( xTimerQueue, &xMessage, tmrNO_DELAY ) != pdFAIL )\r
{\r
pxTimer = xMessage.pxTimer;\r
\r
- /* Is the timer already in the list of active timers? */\r
- if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE )\r
+ /* Is the timer already in a list of active timers? When the command\r
+ is trmCOMMAND_PROCESS_TIMER_OVERFLOW, the timer will be NULL as the\r
+ command is to the task rather than to an individual timer. */\r
+ if( pxTimer != NULL )\r
{\r
- /* The timer is in the list, remove it. */\r
- vListRemove( &( pxTimer->xTimerListItem ) );\r
+ if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE )\r
+ {\r
+ /* The timer is in a list, remove it. */\r
+ vListRemove( &( pxTimer->xTimerListItem ) );\r
+ }\r
}\r
\r
+ traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.xMessageValue );\r
+ \r
switch( xMessage.xMessageID )\r
{\r
case tmrCOMMAND_START : \r
/* Start or restart a timer. */\r
- xTimeToExpire = xTaskGetTickCount() + pxTimer->xTimerPeriodInTicks;\r
- listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xTimeToExpire );\r
- listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );\r
- vListInsert( &xActiveTimerList, &( pxTimer->xTimerListItem ) );\r
+ if( prvInsertTimerInActiveList( pxTimer, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.xMessageValue ) == pdTRUE )\r
+ {\r
+ /* The timer expired before it was added to the active timer\r
+ list. Process it now. */\r
+ pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );\r
+\r
+ if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )\r
+ {\r
+ xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, NULL, tmrNO_DELAY );\r
+ configASSERT( xResult );\r
+ ( void ) xResult;\r
+ }\r
+ }\r
break;\r
\r
case tmrCOMMAND_STOP : \r
\r
case tmrCOMMAND_CHANGE_PERIOD :\r
pxTimer->xTimerPeriodInTicks = xMessage.xMessageValue;\r
- xTimeToExpire = xTaskGetTickCount() + pxTimer->xTimerPeriodInTicks;\r
- listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xTimeToExpire );\r
- listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );\r
- vListInsert( &xActiveTimerList, &( pxTimer->xTimerListItem ) );\r
+ configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );\r
+ prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );\r
break;\r
\r
case tmrCOMMAND_DELETE :\r
}\r
/*-----------------------------------------------------------*/\r
\r
+static void prvSwitchTimerLists( portTickType xLastTime )\r
+{\r
+portTickType xNextExpireTime, xReloadTime;\r
+xList *pxTemp;\r
+xTIMER *pxTimer;\r
+portBASE_TYPE xResult;\r
+\r
+ /* Remove compiler warnings if configASSERT() is not defined. */\r
+ ( void ) xLastTime;\r
+ \r
+ /* The tick count has overflowed. The timer lists must be switched.\r
+ If there are any timers still referenced from the current timer list\r
+ then they must have expired and should be processed before the lists\r
+ are switched. */\r
+ while( listLIST_IS_EMPTY( pxCurrentTimerList ) == pdFALSE )\r
+ {\r
+ xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );\r
+\r
+ /* Remove the timer from the list. */\r
+ pxTimer = ( xTIMER * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );\r
+ vListRemove( &( pxTimer->xTimerListItem ) );\r
+\r
+ /* Execute its callback, then send a command to restart the timer if\r
+ it is an auto-reload timer. It cannot be restarted here as the lists\r
+ have not yet been switched. */\r
+ pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );\r
+\r
+ if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )\r
+ {\r
+ /* Calculate the reload value, and if the reload value results in\r
+ the timer going into the same timer list then it has already expired\r
+ and the timer should be re-inserted into the current list so it is\r
+ processed again within this loop. Otherwise a command should be sent\r
+ to restart the timer to ensure it is only inserted into a list after\r
+ the lists have been swapped. */\r
+ xReloadTime = ( xNextExpireTime + pxTimer->xTimerPeriodInTicks );\r
+ if( xReloadTime > xNextExpireTime )\r
+ {\r
+ listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xReloadTime );\r
+ listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );\r
+ vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );\r
+ }\r
+ else\r
+ {\r
+ xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xNextExpireTime, NULL, tmrNO_DELAY );\r
+ configASSERT( xResult );\r
+ ( void ) xResult;\r
+ }\r
+ }\r
+ }\r
+\r
+ pxTemp = pxCurrentTimerList;\r
+ pxCurrentTimerList = pxOverflowTimerList;\r
+ pxOverflowTimerList = pxTemp;\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
static void prvCheckForValidListAndQueue( void )\r
{\r
/* Check that the list from which active timers are referenced, and the\r
- queue used to communicate with the timer service, have been \r
+ queue used to communicate with the timer service, have been\r
initialised. */\r
taskENTER_CRITICAL();\r
{\r
if( xTimerQueue == NULL )\r
{\r
- vListInitialise( &xActiveTimerList );\r
- xTimerQueue = xQueueCreate( configTIMER_QUEUE_LENGTH, sizeof( xTIMER_MESSAGE ) );\r
+ vListInitialise( &xActiveTimerList1 );\r
+ vListInitialise( &xActiveTimerList2 );\r
+ pxCurrentTimerList = &xActiveTimerList1;\r
+ pxOverflowTimerList = &xActiveTimerList2;\r
+ xTimerQueue = xQueueCreate( ( unsigned portBASE_TYPE ) configTIMER_QUEUE_LENGTH, sizeof( xTIMER_MESSAGE ) );\r
}\r
}\r
taskEXIT_CRITICAL();\r
/* Is the timer in the list of active timers? */\r
taskENTER_CRITICAL();\r
{\r
- xTimerIsInActiveList = listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) );\r
+ /* Checking to see if it is in the NULL list in effect checks to see if\r
+ it is referenced from either the current or the overflow timer lists in\r
+ one go, but the logic has to be reversed, hence the '!'. */\r
+ xTimerIsInActiveList = !( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) );\r
}\r
taskEXIT_CRITICAL();\r
\r
}\r
/*-----------------------------------------------------------*/\r
\r
+/* This entire source file will be skipped if the application is not configured\r
+to include software timer functionality. If you want to include software timer\r
+functionality then ensure configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */\r
+#endif /* configUSE_TIMERS == 1 */\r
projects / freertos / blobdiff