| /* |
| * FreeRTOS Kernel <DEVELOPMENT BRANCH> |
| * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
| * |
| * SPDX-License-Identifier: MIT |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy of |
| * this software and associated documentation files (the "Software"), to deal in |
| * the Software without restriction, including without limitation the rights to |
| * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of |
| * the Software, and to permit persons to whom the Software is furnished to do so, |
| * subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in all |
| * copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS |
| * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR |
| * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER |
| * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
| * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| * |
| * https://www.FreeRTOS.org |
| * https://github.com/FreeRTOS |
| * |
| */ |
| |
| #include "FreeRTOS.h" |
| #include "task.h" |
| #include "croutine.h" |
| |
| /* Remove the whole file is co-routines are not being used. */ |
| #if ( configUSE_CO_ROUTINES != 0 ) |
| |
| /* |
| * Some kernel aware debuggers require data to be viewed to be global, rather |
| * than file scope. |
| */ |
| #ifdef portREMOVE_STATIC_QUALIFIER |
| #define static |
| #endif |
| |
| |
| /* Lists for ready and blocked co-routines. --------------------*/ |
| static List_t pxReadyCoRoutineLists[ configMAX_CO_ROUTINE_PRIORITIES ]; /**< Prioritised ready co-routines. */ |
| static List_t xDelayedCoRoutineList1; /**< Delayed co-routines. */ |
| static List_t xDelayedCoRoutineList2; /**< Delayed co-routines (two lists are used - one for delays that have overflowed the current tick count. */ |
| static List_t * pxDelayedCoRoutineList = NULL; /**< Points to the delayed co-routine list currently being used. */ |
| static List_t * pxOverflowDelayedCoRoutineList = NULL; /**< Points to the delayed co-routine list currently being used to hold co-routines that have overflowed the current tick count. */ |
| static List_t xPendingReadyCoRoutineList; /**< Holds co-routines that have been readied by an external event. They cannot be added directly to the ready lists as the ready lists cannot be accessed by interrupts. */ |
| |
| /* Other file private variables. --------------------------------*/ |
| CRCB_t * pxCurrentCoRoutine = NULL; |
| static UBaseType_t uxTopCoRoutineReadyPriority = 0; |
| static TickType_t xCoRoutineTickCount = 0, xLastTickCount = 0, xPassedTicks = 0; |
| |
| /* The initial state of the co-routine when it is created. */ |
| #define corINITIAL_STATE ( 0 ) |
| |
| /* |
| * Place the co-routine represented by pxCRCB into the appropriate ready queue |
| * for the priority. It is inserted at the end of the list. |
| * |
| * This macro accesses the co-routine ready lists and therefore must not be |
| * used from within an ISR. |
| */ |
| #define prvAddCoRoutineToReadyQueue( pxCRCB ) \ |
| do { \ |
| if( ( pxCRCB )->uxPriority > uxTopCoRoutineReadyPriority ) \ |
| { \ |
| uxTopCoRoutineReadyPriority = ( pxCRCB )->uxPriority; \ |
| } \ |
| vListInsertEnd( ( List_t * ) &( pxReadyCoRoutineLists[ ( pxCRCB )->uxPriority ] ), &( ( pxCRCB )->xGenericListItem ) ); \ |
| } while( 0 ) |
| |
| /* |
| * Utility to ready all the lists used by the scheduler. This is called |
| * automatically upon the creation of the first co-routine. |
| */ |
| static void prvInitialiseCoRoutineLists( void ); |
| |
| /* |
| * Co-routines that are readied by an interrupt cannot be placed directly into |
| * the ready lists (there is no mutual exclusion). Instead they are placed in |
| * in the pending ready list in order that they can later be moved to the ready |
| * list by the co-routine scheduler. |
| */ |
| static void prvCheckPendingReadyList( void ); |
| |
| /* |
| * Macro that looks at the list of co-routines that are currently delayed to |
| * see if any require waking. |
| * |
| * Co-routines are stored in the queue in the order of their wake time - |
| * meaning once one co-routine has been found whose timer has not expired |
| * we need not look any further down the list. |
| */ |
| static void prvCheckDelayedList( void ); |
| |
| /*-----------------------------------------------------------*/ |
| |
| BaseType_t xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, |
| UBaseType_t uxPriority, |
| UBaseType_t uxIndex ) |
| { |
| BaseType_t xReturn; |
| CRCB_t * pxCoRoutine; |
| |
| /* Allocate the memory that will store the co-routine control block. */ |
| pxCoRoutine = ( CRCB_t * ) pvPortMalloc( sizeof( CRCB_t ) ); |
| |
| if( pxCoRoutine ) |
| { |
| /* If pxCurrentCoRoutine is NULL then this is the first co-routine to |
| * be created and the co-routine data structures need initialising. */ |
| if( pxCurrentCoRoutine == NULL ) |
| { |
| pxCurrentCoRoutine = pxCoRoutine; |
| prvInitialiseCoRoutineLists(); |
| } |
| |
| /* Check the priority is within limits. */ |
| if( uxPriority >= configMAX_CO_ROUTINE_PRIORITIES ) |
| { |
| uxPriority = configMAX_CO_ROUTINE_PRIORITIES - 1; |
| } |
| |
| /* Fill out the co-routine control block from the function parameters. */ |
| pxCoRoutine->uxState = corINITIAL_STATE; |
| pxCoRoutine->uxPriority = uxPriority; |
| pxCoRoutine->uxIndex = uxIndex; |
| pxCoRoutine->pxCoRoutineFunction = pxCoRoutineCode; |
| |
| /* Initialise all the other co-routine control block parameters. */ |
| vListInitialiseItem( &( pxCoRoutine->xGenericListItem ) ); |
| vListInitialiseItem( &( pxCoRoutine->xEventListItem ) ); |
| |
| /* Set the co-routine control block as a link back from the ListItem_t. |
| * This is so we can get back to the containing CRCB from a generic item |
| * in a list. */ |
| listSET_LIST_ITEM_OWNER( &( pxCoRoutine->xGenericListItem ), pxCoRoutine ); |
| listSET_LIST_ITEM_OWNER( &( pxCoRoutine->xEventListItem ), pxCoRoutine ); |
| |
| /* Event lists are always in priority order. */ |
| listSET_LIST_ITEM_VALUE( &( pxCoRoutine->xEventListItem ), ( ( TickType_t ) configMAX_CO_ROUTINE_PRIORITIES - ( TickType_t ) uxPriority ) ); |
| |
| /* Now the co-routine has been initialised it can be added to the ready |
| * list at the correct priority. */ |
| prvAddCoRoutineToReadyQueue( pxCoRoutine ); |
| |
| xReturn = pdPASS; |
| } |
| else |
| { |
| xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY; |
| } |
| |
| return xReturn; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vCoRoutineAddToDelayedList( TickType_t xTicksToDelay, |
| List_t * pxEventList ) |
| { |
| TickType_t xTimeToWake; |
| |
| /* Calculate the time to wake - this may overflow but this is |
| * not a problem. */ |
| xTimeToWake = xCoRoutineTickCount + xTicksToDelay; |
| |
| /* We must remove ourselves from the ready list before adding |
| * ourselves to the blocked list as the same list item is used for |
| * both lists. */ |
| ( void ) uxListRemove( ( ListItem_t * ) &( pxCurrentCoRoutine->xGenericListItem ) ); |
| |
| /* The list item will be inserted in wake time order. */ |
| listSET_LIST_ITEM_VALUE( &( pxCurrentCoRoutine->xGenericListItem ), xTimeToWake ); |
| |
| if( xTimeToWake < xCoRoutineTickCount ) |
| { |
| /* Wake time has overflowed. Place this item in the |
| * overflow list. */ |
| vListInsert( ( List_t * ) pxOverflowDelayedCoRoutineList, ( ListItem_t * ) &( pxCurrentCoRoutine->xGenericListItem ) ); |
| } |
| else |
| { |
| /* The wake time has not overflowed, so we can use the |
| * current block list. */ |
| vListInsert( ( List_t * ) pxDelayedCoRoutineList, ( ListItem_t * ) &( pxCurrentCoRoutine->xGenericListItem ) ); |
| } |
| |
| if( pxEventList ) |
| { |
| /* Also add the co-routine to an event list. If this is done then the |
| * function must be called with interrupts disabled. */ |
| vListInsert( pxEventList, &( pxCurrentCoRoutine->xEventListItem ) ); |
| } |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvCheckPendingReadyList( void ) |
| { |
| /* Are there any co-routines waiting to get moved to the ready list? These |
| * are co-routines that have been readied by an ISR. The ISR cannot access |
| * the ready lists itself. */ |
| while( listLIST_IS_EMPTY( &xPendingReadyCoRoutineList ) == pdFALSE ) |
| { |
| CRCB_t * pxUnblockedCRCB; |
| |
| /* The pending ready list can be accessed by an ISR. */ |
| portDISABLE_INTERRUPTS(); |
| { |
| pxUnblockedCRCB = ( CRCB_t * ) listGET_OWNER_OF_HEAD_ENTRY( ( &xPendingReadyCoRoutineList ) ); |
| ( void ) uxListRemove( &( pxUnblockedCRCB->xEventListItem ) ); |
| } |
| portENABLE_INTERRUPTS(); |
| |
| ( void ) uxListRemove( &( pxUnblockedCRCB->xGenericListItem ) ); |
| prvAddCoRoutineToReadyQueue( pxUnblockedCRCB ); |
| } |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvCheckDelayedList( void ) |
| { |
| CRCB_t * pxCRCB; |
| |
| xPassedTicks = xTaskGetTickCount() - xLastTickCount; |
| |
| while( xPassedTicks ) |
| { |
| xCoRoutineTickCount++; |
| xPassedTicks--; |
| |
| /* If the tick count has overflowed we need to swap the ready lists. */ |
| if( xCoRoutineTickCount == 0 ) |
| { |
| List_t * pxTemp; |
| |
| /* Tick count has overflowed so we need to swap the delay lists. If there are |
| * any items in pxDelayedCoRoutineList here then there is an error! */ |
| pxTemp = pxDelayedCoRoutineList; |
| pxDelayedCoRoutineList = pxOverflowDelayedCoRoutineList; |
| pxOverflowDelayedCoRoutineList = pxTemp; |
| } |
| |
| /* See if this tick has made a timeout expire. */ |
| while( listLIST_IS_EMPTY( pxDelayedCoRoutineList ) == pdFALSE ) |
| { |
| pxCRCB = ( CRCB_t * ) listGET_OWNER_OF_HEAD_ENTRY( pxDelayedCoRoutineList ); |
| |
| if( xCoRoutineTickCount < listGET_LIST_ITEM_VALUE( &( pxCRCB->xGenericListItem ) ) ) |
| { |
| /* Timeout not yet expired. */ |
| break; |
| } |
| |
| portDISABLE_INTERRUPTS(); |
| { |
| /* The event could have occurred just before this critical |
| * section. If this is the case then the generic list item will |
| * have been moved to the pending ready list and the following |
| * line is still valid. Also the pvContainer parameter will have |
| * been set to NULL so the following lines are also valid. */ |
| ( void ) uxListRemove( &( pxCRCB->xGenericListItem ) ); |
| |
| /* Is the co-routine waiting on an event also? */ |
| if( pxCRCB->xEventListItem.pxContainer ) |
| { |
| ( void ) uxListRemove( &( pxCRCB->xEventListItem ) ); |
| } |
| } |
| portENABLE_INTERRUPTS(); |
| |
| prvAddCoRoutineToReadyQueue( pxCRCB ); |
| } |
| } |
| |
| xLastTickCount = xCoRoutineTickCount; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vCoRoutineSchedule( void ) |
| { |
| /* Only run a co-routine after prvInitialiseCoRoutineLists() has been |
| * called. prvInitialiseCoRoutineLists() is called automatically when a |
| * co-routine is created. */ |
| if( pxDelayedCoRoutineList != NULL ) |
| { |
| /* See if any co-routines readied by events need moving to the ready lists. */ |
| prvCheckPendingReadyList(); |
| |
| /* See if any delayed co-routines have timed out. */ |
| prvCheckDelayedList(); |
| |
| /* Find the highest priority queue that contains ready co-routines. */ |
| while( listLIST_IS_EMPTY( &( pxReadyCoRoutineLists[ uxTopCoRoutineReadyPriority ] ) ) ) |
| { |
| if( uxTopCoRoutineReadyPriority == 0 ) |
| { |
| /* No more co-routines to check. */ |
| return; |
| } |
| |
| --uxTopCoRoutineReadyPriority; |
| } |
| |
| /* listGET_OWNER_OF_NEXT_ENTRY walks through the list, so the co-routines |
| * of the same priority get an equal share of the processor time. */ |
| listGET_OWNER_OF_NEXT_ENTRY( pxCurrentCoRoutine, &( pxReadyCoRoutineLists[ uxTopCoRoutineReadyPriority ] ) ); |
| |
| /* Call the co-routine. */ |
| ( pxCurrentCoRoutine->pxCoRoutineFunction )( pxCurrentCoRoutine, pxCurrentCoRoutine->uxIndex ); |
| } |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvInitialiseCoRoutineLists( void ) |
| { |
| UBaseType_t uxPriority; |
| |
| for( uxPriority = 0; uxPriority < configMAX_CO_ROUTINE_PRIORITIES; uxPriority++ ) |
| { |
| vListInitialise( ( List_t * ) &( pxReadyCoRoutineLists[ uxPriority ] ) ); |
| } |
| |
| vListInitialise( ( List_t * ) &xDelayedCoRoutineList1 ); |
| vListInitialise( ( List_t * ) &xDelayedCoRoutineList2 ); |
| vListInitialise( ( List_t * ) &xPendingReadyCoRoutineList ); |
| |
| /* Start with pxDelayedCoRoutineList using list1 and the |
| * pxOverflowDelayedCoRoutineList using list2. */ |
| pxDelayedCoRoutineList = &xDelayedCoRoutineList1; |
| pxOverflowDelayedCoRoutineList = &xDelayedCoRoutineList2; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| BaseType_t xCoRoutineRemoveFromEventList( const List_t * pxEventList ) |
| { |
| CRCB_t * pxUnblockedCRCB; |
| BaseType_t xReturn; |
| |
| /* This function is called from within an interrupt. It can only access |
| * event lists and the pending ready list. This function assumes that a |
| * check has already been made to ensure pxEventList is not empty. */ |
| pxUnblockedCRCB = ( CRCB_t * ) listGET_OWNER_OF_HEAD_ENTRY( pxEventList ); |
| ( void ) uxListRemove( &( pxUnblockedCRCB->xEventListItem ) ); |
| vListInsertEnd( ( List_t * ) &( xPendingReadyCoRoutineList ), &( pxUnblockedCRCB->xEventListItem ) ); |
| |
| if( pxUnblockedCRCB->uxPriority >= pxCurrentCoRoutine->uxPriority ) |
| { |
| xReturn = pdTRUE; |
| } |
| else |
| { |
| xReturn = pdFALSE; |
| } |
| |
| return xReturn; |
| } |
| |
| #endif /* configUSE_CO_ROUTINES == 0 */ |
