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tasks.c
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/*
* FreeRTOS Kernel V10.0.1
* Copyright (C) 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* 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.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
/* Standard includes. */
#include <stdlib.h>
#include <string.h>
/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
all the API functions to use the MPU wrappers. That should only be done when
task.h is included from an application file. */
#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "timers.h"
#include "stack_macros.h"
/* Lint e961 and e750 are suppressed as a MISRA exception justified because the
MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined for the
header files above, but not in this file, in order to generate the correct
privileged Vs unprivileged linkage and placement. */
#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750. */
/* Set configUSE_STATS_FORMATTING_FUNCTIONS to 2 to include the stats formatting
functions but without including stdio.h here. */
#if ( configUSE_STATS_FORMATTING_FUNCTIONS == 1 )
/* At the bottom of this file are two optional functions that can be used
to generate human readable text from the raw data generated by the
uxTaskGetSystemState() function. Note the formatting functions are provided
for convenience only, and are NOT considered part of the kernel. */
#include <stdio.h>
#endif /* configUSE_STATS_FORMATTING_FUNCTIONS == 1 ) */
#if( configUSE_PREEMPTION == 0 )
/* If the cooperative scheduler is being used then a yield should not be
performed just because a higher priority task has been woken. */
#define taskYIELD_IF_USING_PREEMPTION()
#else
#define taskYIELD_IF_USING_PREEMPTION() portYIELD_WITHIN_API()
#endif
/* Values that can be assigned to the ucNotifyState member of the TCB. */
#define taskNOT_WAITING_NOTIFICATION ( ( uint8_t ) 0 )
#define taskWAITING_NOTIFICATION ( ( uint8_t ) 1 )
#define taskNOTIFICATION_RECEIVED ( ( uint8_t ) 2 )
/*
* The value used to fill the stack of a task when the task is created. This
* is used purely for checking the high water mark for tasks.
*/
#define tskSTACK_FILL_BYTE ( 0xa5U )
/* Sometimes the FreeRTOSConfig.h settings only allow a task to be created using
dynamically allocated RAM, in which case when any task is deleted it is known
that both the task's stack and TCB need to be freed. Sometimes the
FreeRTOSConfig.h settings only allow a task to be created using statically
allocated RAM, in which case when any task is deleted it is known that neither
the task's stack or TCB should be freed. Sometimes the FreeRTOSConfig.h
settings allow a task to be created using either statically or dynamically
allocated RAM, in which case a member of the TCB is used to record whether the
stack and/or TCB were allocated statically or dynamically, so when a task is
deleted the RAM that was allocated dynamically is freed again and no attempt is
made to free the RAM that was allocated statically.
tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE is only true if it is possible for a
task to be created using either statically or dynamically allocated RAM. Note
that if portUSING_MPU_WRAPPERS is 1 then a protected task can be created with
a statically allocated stack and a dynamically allocated TCB.
!!!NOTE!!! If the definition of tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE is
changed then the definition of StaticTask_t must also be updated. */
#define tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE ( ( configSUPPORT_STATIC_ALLOCATION == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
#define tskDYNAMICALLY_ALLOCATED_STACK_AND_TCB ( ( uint8_t ) 0 )
#define tskSTATICALLY_ALLOCATED_STACK_ONLY ( ( uint8_t ) 1 )
#define tskSTATICALLY_ALLOCATED_STACK_AND_TCB ( ( uint8_t ) 2 )
/* If any of the following are set then task stacks are filled with a known
value so the high water mark can be determined. If none of the following are
set then don't fill the stack so there is no unnecessary dependency on memset. */
#if( ( configCHECK_FOR_STACK_OVERFLOW > 1 ) || ( configUSE_TRACE_FACILITY == 1 ) || ( INCLUDE_uxTaskGetStackHighWaterMark == 1 ) )
#define tskSET_NEW_STACKS_TO_KNOWN_VALUE 1
#else
#define tskSET_NEW_STACKS_TO_KNOWN_VALUE 0
#endif
/*
* Macros used by vListTask to indicate which state a task is in.
*/
#define tskRUNNING_CHAR ( 'X' )
#define tskBLOCKED_CHAR ( 'B' )
#define tskREADY_CHAR ( 'R' )
#define tskDELETED_CHAR ( 'D' )
#define tskSUSPENDED_CHAR ( 'S' )
/*
* Some kernel aware debuggers require the data the debugger needs access to be
* global, rather than file scope.
*/
#ifdef portREMOVE_STATIC_QUALIFIER
#define static
#endif
/* The name allocated to the Idle task. This can be overridden by defining
configIDLE_TASK_NAME in FreeRTOSConfig.h. */
#ifndef configIDLE_TASK_NAME
#define configIDLE_TASK_NAME "IDLE"
#endif
#if ( configUSE_PORT_OPTIMISED_TASK_SELECTION == 0 )
/* If configUSE_PORT_OPTIMISED_TASK_SELECTION is 0 then task selection is
performed in a generic way that is not optimised to any particular
microcontroller architecture. */
/* uxTopReadyPriority holds the priority of the highest priority ready
state task. */
#define taskRECORD_READY_PRIORITY( uxPriority ) \
{ \
if( ( uxPriority ) > uxTopReadyPriority ) \
{ \
uxTopReadyPriority = ( uxPriority ); \
} \
} /* taskRECORD_READY_PRIORITY */
/*-----------------------------------------------------------*/
#define taskSELECT_HIGHEST_PRIORITY_TASK() \
{ \
UBaseType_t uxTopPriority = uxTopReadyPriority; \
\
/* Find the highest priority queue that contains ready tasks. */ \
while( listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxTopPriority ] ) ) ) \
{ \
configASSERT( uxTopPriority ); \
--uxTopPriority; \
} \
\
/* listGET_OWNER_OF_NEXT_ENTRY indexes through the list, so the tasks of \
the same priority get an equal share of the processor time. */ \
listGET_OWNER_OF_NEXT_ENTRY( pxCurrentTCB, &( pxReadyTasksLists[ uxTopPriority ] ) ); \
uxTopReadyPriority = uxTopPriority; \
} /* taskSELECT_HIGHEST_PRIORITY_TASK */
/*-----------------------------------------------------------*/
/* Define away taskRESET_READY_PRIORITY() and portRESET_READY_PRIORITY() as
they are only required when a port optimised method of task selection is
being used. */
#define taskRESET_READY_PRIORITY( uxPriority )
#define portRESET_READY_PRIORITY( uxPriority, uxTopReadyPriority )
#else /* configUSE_PORT_OPTIMISED_TASK_SELECTION */
/* If configUSE_PORT_OPTIMISED_TASK_SELECTION is 1 then task selection is
performed in a way that is tailored to the particular microcontroller
architecture being used. */
/* A port optimised version is provided. Call the port defined macros. */
#define taskRECORD_READY_PRIORITY( uxPriority ) portRECORD_READY_PRIORITY( uxPriority, uxTopReadyPriority )
/*-----------------------------------------------------------*/
#define taskSELECT_HIGHEST_PRIORITY_TASK() \
{ \
UBaseType_t uxTopPriority; \
\
/* Find the highest priority list that contains ready tasks. */ \
portGET_HIGHEST_PRIORITY( uxTopPriority, uxTopReadyPriority ); \
configASSERT( listCURRENT_LIST_LENGTH( &( pxReadyTasksLists[ uxTopPriority ] ) ) > 0 ); \
listGET_OWNER_OF_NEXT_ENTRY( pxCurrentTCB, &( pxReadyTasksLists[ uxTopPriority ] ) ); \
} /* taskSELECT_HIGHEST_PRIORITY_TASK() */
/*-----------------------------------------------------------*/
/* A port optimised version is provided, call it only if the TCB being reset
is being referenced from a ready list. If it is referenced from a delayed
or suspended list then it won't be in a ready list. */
#define taskRESET_READY_PRIORITY( uxPriority ) \
{ \
if( listCURRENT_LIST_LENGTH( &( pxReadyTasksLists[ ( uxPriority ) ] ) ) == ( UBaseType_t ) 0 ) \
{ \
portRESET_READY_PRIORITY( ( uxPriority ), ( uxTopReadyPriority ) ); \
} \
}
#endif /* configUSE_PORT_OPTIMISED_TASK_SELECTION */
/*-----------------------------------------------------------*/
/* pxDelayedTaskList and pxOverflowDelayedTaskList are switched when the tick
count overflows. */
#define taskSWITCH_DELAYED_LISTS() \
{ \
List_t *pxTemp; \
\
/* The delayed tasks list should be empty when the lists are switched. */ \
configASSERT( ( listLIST_IS_EMPTY( pxDelayedTaskList ) ) ); \
\
pxTemp = pxDelayedTaskList; \
pxDelayedTaskList = pxOverflowDelayedTaskList; \
pxOverflowDelayedTaskList = pxTemp; \
xNumOfOverflows++; \
prvResetNextTaskUnblockTime(); \
}
/*-----------------------------------------------------------*/
/*
* Place the task represented by pxTCB into the appropriate ready list for
* the task. It is inserted at the end of the list.
*/
#define prvAddTaskToReadyList( pxTCB ) \
traceMOVED_TASK_TO_READY_STATE( pxTCB ); \
taskRECORD_READY_PRIORITY( ( pxTCB )->uxPriority ); \
vListInsertEnd( &( pxReadyTasksLists[ ( pxTCB )->uxPriority ] ), &( ( pxTCB )->xStateListItem ) ); \
tracePOST_MOVED_TASK_TO_READY_STATE( pxTCB )
/*-----------------------------------------------------------*/
/*
* Several functions take an TaskHandle_t parameter that can optionally be NULL,
* where NULL is used to indicate that the handle of the currently executing
* task should be used in place of the parameter. This macro simply checks to
* see if the parameter is NULL and returns a pointer to the appropriate TCB.
*/
#define prvGetTCBFromHandle( pxHandle ) ( ( ( pxHandle ) == NULL ) ? ( TCB_t * ) pxCurrentTCB : ( TCB_t * ) ( pxHandle ) )
/* The item value of the event list item is normally used to hold the priority
of the task to which it belongs (coded to allow it to be held in reverse
priority order). However, it is occasionally borrowed for other purposes. It
is important its value is not updated due to a task priority change while it is
being used for another purpose. The following bit definition is used to inform
the scheduler that the value should not be changed - in which case it is the
responsibility of whichever module is using the value to ensure it gets set back
to its original value when it is released. */
#if( configUSE_16_BIT_TICKS == 1 )
#define taskEVENT_LIST_ITEM_VALUE_IN_USE 0x8000U
#else
#define taskEVENT_LIST_ITEM_VALUE_IN_USE 0x80000000UL
#endif
/*
* Task control block. A task control block (TCB) is allocated for each task,
* and stores task state information, including a pointer to the task's context
* (the task's run time environment, including register values)
*/
typedef struct tskTaskControlBlock
{
volatile StackType_t *pxTopOfStack; /*< Points to the location of the last item placed on the tasks stack. THIS MUST BE THE FIRST MEMBER OF THE TCB STRUCT. */
#if ( portUSING_MPU_WRAPPERS == 1 )
xMPU_SETTINGS xMPUSettings; /*< The MPU settings are defined as part of the port layer. THIS MUST BE THE SECOND MEMBER OF THE TCB STRUCT. */
#endif
ListItem_t xStateListItem; /*< The list that the state list item of a task is reference from denotes the state of that task (Ready, Blocked, Suspended ). */
ListItem_t xEventListItem; /*< Used to reference a task from an event list. */
UBaseType_t uxPriority; /*< The priority of the task. 0 is the lowest priority. */
StackType_t *pxStack; /*< Points to the start of the stack. */
char pcTaskName[ configMAX_TASK_NAME_LEN ];/*< Descriptive name given to the task when created. Facilitates debugging only. */ /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
#if ( ( portSTACK_GROWTH > 0 ) || ( configRECORD_STACK_HIGH_ADDRESS == 1 ) )
StackType_t *pxEndOfStack; /*< Points to the highest valid address for the stack. */
#endif
#if ( portCRITICAL_NESTING_IN_TCB == 1 )
UBaseType_t uxCriticalNesting; /*< Holds the critical section nesting depth for ports that do not maintain their own count in the port layer. */
#endif
#if ( configUSE_TRACE_FACILITY == 1 )
UBaseType_t uxTCBNumber; /*< Stores a number that increments each time a TCB is created. It allows debuggers to determine when a task has been deleted and then recreated. */
UBaseType_t uxTaskNumber; /*< Stores a number specifically for use by third party trace code. */
#endif
#if ( configUSE_MUTEXES == 1 )
UBaseType_t uxBasePriority; /*< The priority last assigned to the task - used by the priority inheritance mechanism. */
UBaseType_t uxMutexesHeld;
#endif
#if ( configUSE_APPLICATION_TASK_TAG == 1 )
TaskHookFunction_t pxTaskTag;
#endif
#if( configNUM_THREAD_LOCAL_STORAGE_POINTERS > 0 )
void *pvThreadLocalStoragePointers[ configNUM_THREAD_LOCAL_STORAGE_POINTERS ];
#endif
#if( configGENERATE_RUN_TIME_STATS == 1 )
uint32_t ulRunTimeCounter; /*< Stores the amount of time the task has spent in the Running state. */
#endif
#if ( configUSE_NEWLIB_REENTRANT == 1 )
/* Allocate a Newlib reent structure that is specific to this task.
Note Newlib support has been included by popular demand, but is not
used by the FreeRTOS maintainers themselves. FreeRTOS is not
responsible for resulting newlib operation. User must be familiar with
newlib and must provide system-wide implementations of the necessary
stubs. Be warned that (at the time of writing) the current newlib design
implements a system-wide malloc() that must be provided with locks. */
struct _reent xNewLib_reent;
#endif
#if( configUSE_TASK_NOTIFICATIONS == 1 )
volatile uint32_t ulNotifiedValue;
volatile uint8_t ucNotifyState;
#endif
/* See the comments above the definition of
tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE. */
#if( tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE != 0 ) /*lint !e731 Macro has been consolidated for readability reasons. */
uint8_t ucStaticallyAllocated; /*< Set to pdTRUE if the task is a statically allocated to ensure no attempt is made to free the memory. */
#endif
#if( INCLUDE_xTaskAbortDelay == 1 )
uint8_t ucDelayAborted;
#endif
} tskTCB;
/* The old tskTCB name is maintained above then typedefed to the new TCB_t name
below to enable the use of older kernel aware debuggers. */
typedef tskTCB TCB_t;
/*lint -save -e956 A manual analysis and inspection has been used to determine
which static variables must be declared volatile. */
PRIVILEGED_DATA TCB_t * volatile pxCurrentTCB = NULL;
/* Lists for ready and blocked tasks. --------------------*/
PRIVILEGED_DATA static List_t pxReadyTasksLists[ configMAX_PRIORITIES ];/*< Prioritised ready tasks. */
PRIVILEGED_DATA static List_t xDelayedTaskList1; /*< Delayed tasks. */
PRIVILEGED_DATA static List_t xDelayedTaskList2; /*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */
PRIVILEGED_DATA static List_t * volatile pxDelayedTaskList; /*< Points to the delayed task list currently being used. */
PRIVILEGED_DATA static List_t * volatile pxOverflowDelayedTaskList; /*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */
PRIVILEGED_DATA static List_t xPendingReadyList; /*< Tasks that have been readied while the scheduler was suspended. They will be moved to the ready list when the scheduler is resumed. */
#if( INCLUDE_vTaskDelete == 1 )
PRIVILEGED_DATA static List_t xTasksWaitingTermination; /*< Tasks that have been deleted - but their memory not yet freed. */
PRIVILEGED_DATA static volatile UBaseType_t uxDeletedTasksWaitingCleanUp = ( UBaseType_t ) 0U;
#endif
#if ( INCLUDE_vTaskSuspend == 1 )
PRIVILEGED_DATA static List_t xSuspendedTaskList; /*< Tasks that are currently suspended. */
#endif
/* Other file private variables. --------------------------------*/
PRIVILEGED_DATA static volatile UBaseType_t uxCurrentNumberOfTasks = ( UBaseType_t ) 0U;
PRIVILEGED_DATA static volatile TickType_t xTickCount = ( TickType_t ) configINITIAL_TICK_COUNT;
PRIVILEGED_DATA static volatile UBaseType_t uxTopReadyPriority = tskIDLE_PRIORITY;
PRIVILEGED_DATA static volatile BaseType_t xSchedulerRunning = pdFALSE;
PRIVILEGED_DATA static volatile UBaseType_t uxPendedTicks = ( UBaseType_t ) 0U;
PRIVILEGED_DATA static volatile BaseType_t xYieldPending = pdFALSE;
PRIVILEGED_DATA static volatile BaseType_t xNumOfOverflows = ( BaseType_t ) 0;
PRIVILEGED_DATA static UBaseType_t uxTaskNumber = ( UBaseType_t ) 0U;
PRIVILEGED_DATA static volatile TickType_t xNextTaskUnblockTime = ( TickType_t ) 0U; /* Initialised to portMAX_DELAY before the scheduler starts. */
PRIVILEGED_DATA static TaskHandle_t xIdleTaskHandle = NULL; /*< Holds the handle of the idle task. The idle task is created automatically when the scheduler is started. */
/* Context switches are held pending while the scheduler is suspended. Also,
interrupts must not manipulate the xStateListItem of a TCB, or any of the
lists the xStateListItem can be referenced from, if the scheduler is suspended.
If an interrupt needs to unblock a task while the scheduler is suspended then it
moves the task's event list item into the xPendingReadyList, ready for the
kernel to move the task from the pending ready list into the real ready list
when the scheduler is unsuspended. The pending ready list itself can only be
accessed from a critical section. */
PRIVILEGED_DATA static volatile UBaseType_t uxSchedulerSuspended = ( UBaseType_t ) pdFALSE;
#if ( configGENERATE_RUN_TIME_STATS == 1 )
PRIVILEGED_DATA static uint32_t ulTaskSwitchedInTime = 0UL; /*< Holds the value of a timer/counter the last time a task was switched in. */
PRIVILEGED_DATA static uint32_t ulTotalRunTime = 0UL; /*< Holds the total amount of execution time as defined by the run time counter clock. */
#endif
/*lint -restore */
/*-----------------------------------------------------------*/
/* Callback function prototypes. --------------------------*/
#if( configCHECK_FOR_STACK_OVERFLOW > 0 )
extern void vApplicationStackOverflowHook( TaskHandle_t xTask, char *pcTaskName );
#endif
#if( configUSE_TICK_HOOK > 0 )
extern void vApplicationTickHook( void );
#endif
#if( configSUPPORT_STATIC_ALLOCATION == 1 )
extern void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize );
#endif
/* File private functions. --------------------------------*/
/**
* Utility task that simply returns pdTRUE if the task referenced by xTask is
* currently in the Suspended state, or pdFALSE if the task referenced by xTask
* is in any other state.
*/
#if ( INCLUDE_vTaskSuspend == 1 )
static BaseType_t prvTaskIsTaskSuspended( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
#endif /* INCLUDE_vTaskSuspend */
/*
* Utility to ready all the lists used by the scheduler. This is called
* automatically upon the creation of the first task.
*/
static void prvInitialiseTaskLists( void ) PRIVILEGED_FUNCTION;
/*
* The idle task, which as all tasks is implemented as a never ending loop.
* The idle task is automatically created and added to the ready lists upon
* creation of the first user task.
*
* The portTASK_FUNCTION_PROTO() macro is used to allow port/compiler specific
* language extensions. The equivalent prototype for this function is:
*
* void prvIdleTask( void *pvParameters );
*
*/
static portTASK_FUNCTION_PROTO( prvIdleTask, pvParameters );
/*
* Utility to free all memory allocated by the scheduler to hold a TCB,
* including the stack pointed to by the TCB.
*
* This does not free memory allocated by the task itself (i.e. memory
* allocated by calls to pvPortMalloc from within the tasks application code).
*/
#if ( INCLUDE_vTaskDelete == 1 )
static void prvDeleteTCB( TCB_t *pxTCB ) PRIVILEGED_FUNCTION;
#endif
/*
* Used only by the idle task. This checks to see if anything has been placed
* in the list of tasks waiting to be deleted. If so the task is cleaned up
* and its TCB deleted.
*/
static void prvCheckTasksWaitingTermination( void ) PRIVILEGED_FUNCTION;
/*
* The currently executing task is entering the Blocked state. Add the task to
* either the current or the overflow delayed task list.
*/
static void prvAddCurrentTaskToDelayedList( TickType_t xTicksToWait, const BaseType_t xCanBlockIndefinitely ) PRIVILEGED_FUNCTION;
/*
* Fills an TaskStatus_t structure with information on each task that is
* referenced from the pxList list (which may be a ready list, a delayed list,
* a suspended list, etc.).
*
* THIS FUNCTION IS INTENDED FOR DEBUGGING ONLY, AND SHOULD NOT BE CALLED FROM
* NORMAL APPLICATION CODE.
*/
#if ( configUSE_TRACE_FACILITY == 1 )
static UBaseType_t prvListTasksWithinSingleList( TaskStatus_t *pxTaskStatusArray, List_t *pxList, eTaskState eState ) PRIVILEGED_FUNCTION;
#endif
/*
* Searches pxList for a task with name pcNameToQuery - returning a handle to
* the task if it is found, or NULL if the task is not found.
*/
#if ( INCLUDE_xTaskGetHandle == 1 )
static TCB_t *prvSearchForNameWithinSingleList( List_t *pxList, const char pcNameToQuery[] ) PRIVILEGED_FUNCTION;
#endif
/*
* When a task is created, the stack of the task is filled with a known value.
* This function determines the 'high water mark' of the task stack by
* determining how much of the stack remains at the original preset value.
*/
#if ( ( configUSE_TRACE_FACILITY == 1 ) || ( INCLUDE_uxTaskGetStackHighWaterMark == 1 ) )
static uint16_t prvTaskCheckFreeStackSpace( const uint8_t * pucStackByte ) PRIVILEGED_FUNCTION;
#endif
/*
* Return the amount of time, in ticks, that will pass before the kernel will
* next move a task from the Blocked state to the Running state.
*
* This conditional compilation should use inequality to 0, not equality to 1.
* This is to ensure portSUPPRESS_TICKS_AND_SLEEP() can be called when user
* defined low power mode implementations require configUSE_TICKLESS_IDLE to be
* set to a value other than 1.
*/
#if ( configUSE_TICKLESS_IDLE != 0 )
static TickType_t prvGetExpectedIdleTime( void ) PRIVILEGED_FUNCTION;
#endif
/*
* Set xNextTaskUnblockTime to the time at which the next Blocked state task
* will exit the Blocked state.
*/
static void prvResetNextTaskUnblockTime( void );
#if ( ( configUSE_TRACE_FACILITY == 1 ) && ( configUSE_STATS_FORMATTING_FUNCTIONS > 0 ) )
/*
* Helper function used to pad task names with spaces when printing out
* human readable tables of task information.
*/
static char *prvWriteNameToBuffer( char *pcBuffer, const char *pcTaskName ) PRIVILEGED_FUNCTION;
#endif
/*
* Called after a Task_t structure has been allocated either statically or
* dynamically to fill in the structure's members.
*/
static void prvInitialiseNewTask( TaskFunction_t pxTaskCode,
const char * const pcName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
const uint32_t ulStackDepth,
void * const pvParameters,
UBaseType_t uxPriority,
TaskHandle_t * const pxCreatedTask,
TCB_t *pxNewTCB,
const MemoryRegion_t * const xRegions ) PRIVILEGED_FUNCTION;
/*
* Called after a new task has been created and initialised to place the task
* under the control of the scheduler.
*/
static void prvAddNewTaskToReadyList( TCB_t *pxNewTCB ) PRIVILEGED_FUNCTION;
/*
* freertos_tasks_c_additions_init() should only be called if the user definable
* macro FREERTOS_TASKS_C_ADDITIONS_INIT() is defined, as that is the only macro
* called by the function.
*/
#ifdef FREERTOS_TASKS_C_ADDITIONS_INIT
static void freertos_tasks_c_additions_init( void ) PRIVILEGED_FUNCTION;
#endif
/*-----------------------------------------------------------*/
#if( configSUPPORT_STATIC_ALLOCATION == 1 )
TaskHandle_t xTaskCreateStatic( TaskFunction_t pxTaskCode,
const char * const pcName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
const uint32_t ulStackDepth,
void * const pvParameters,
UBaseType_t uxPriority,
StackType_t * const puxStackBuffer,
StaticTask_t * const pxTaskBuffer )
{
TCB_t *pxNewTCB;
TaskHandle_t xReturn;
configASSERT( puxStackBuffer != NULL );
configASSERT( pxTaskBuffer != NULL );
#if( configASSERT_DEFINED == 1 )
{
/* Sanity check that the size of the structure used to declare a
variable of type StaticTask_t equals the size of the real task
structure. */
volatile size_t xSize = sizeof( StaticTask_t );
configASSERT( xSize == sizeof( TCB_t ) );
}
#endif /* configASSERT_DEFINED */
if( ( pxTaskBuffer != NULL ) && ( puxStackBuffer != NULL ) )
{
/* The memory used for the task's TCB and stack are passed into this
function - use them. */
pxNewTCB = ( TCB_t * ) pxTaskBuffer; /*lint !e740 Unusual cast is ok as the structures are designed to have the same alignment, and the size is checked by an assert. */
pxNewTCB->pxStack = ( StackType_t * ) puxStackBuffer;
#if( tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE != 0 ) /*lint !e731 Macro has been consolidated for readability reasons. */
{
/* Tasks can be created statically or dynamically, so note this
task was created statically in case the task is later deleted. */
pxNewTCB->ucStaticallyAllocated = tskSTATICALLY_ALLOCATED_STACK_AND_TCB;
}
#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
prvInitialiseNewTask( pxTaskCode, pcName, ulStackDepth, pvParameters, uxPriority, &xReturn, pxNewTCB, NULL );
prvAddNewTaskToReadyList( pxNewTCB );
}
else
{
xReturn = NULL;
}
return xReturn;
}
#endif /* SUPPORT_STATIC_ALLOCATION */
/*-----------------------------------------------------------*/
#if( ( portUSING_MPU_WRAPPERS == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
BaseType_t xTaskCreateRestrictedStatic( const TaskParameters_t * const pxTaskDefinition, TaskHandle_t *pxCreatedTask )
{
TCB_t *pxNewTCB;
BaseType_t xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY;
configASSERT( pxTaskDefinition->puxStackBuffer != NULL );
configASSERT( pxTaskDefinition->pxTaskBuffer != NULL );
if( ( pxTaskDefinition->puxStackBuffer != NULL ) && ( pxTaskDefinition->pxTaskBuffer != NULL ) )
{
/* Allocate space for the TCB. Where the memory comes from depends
on the implementation of the port malloc function and whether or
not static allocation is being used. */
pxNewTCB = ( TCB_t * ) pxTaskDefinition->pxTaskBuffer;
/* Store the stack location in the TCB. */
pxNewTCB->pxStack = pxTaskDefinition->puxStackBuffer;
#if( tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE != 0 )
{
/* Tasks can be created statically or dynamically, so note this
task was created statically in case the task is later deleted. */
pxNewTCB->ucStaticallyAllocated = tskSTATICALLY_ALLOCATED_STACK_AND_TCB;
}
#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
prvInitialiseNewTask( pxTaskDefinition->pvTaskCode,
pxTaskDefinition->pcName,
( uint32_t ) pxTaskDefinition->usStackDepth,
pxTaskDefinition->pvParameters,
pxTaskDefinition->uxPriority,
pxCreatedTask, pxNewTCB,
pxTaskDefinition->xRegions );
prvAddNewTaskToReadyList( pxNewTCB );
xReturn = pdPASS;
}
return xReturn;
}
#endif /* ( portUSING_MPU_WRAPPERS == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) */
/*-----------------------------------------------------------*/
#if( ( portUSING_MPU_WRAPPERS == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
BaseType_t xTaskCreateRestricted( const TaskParameters_t * const pxTaskDefinition, TaskHandle_t *pxCreatedTask )
{
TCB_t *pxNewTCB;
BaseType_t xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY;
configASSERT( pxTaskDefinition->puxStackBuffer );
if( pxTaskDefinition->puxStackBuffer != NULL )
{
/* Allocate space for the TCB. Where the memory comes from depends
on the implementation of the port malloc function and whether or
not static allocation is being used. */
pxNewTCB = ( TCB_t * ) pvPortMalloc( sizeof( TCB_t ) );
if( pxNewTCB != NULL )
{
/* Store the stack location in the TCB. */
pxNewTCB->pxStack = pxTaskDefinition->puxStackBuffer;
#if( configSUPPORT_STATIC_ALLOCATION == 1 )
{
/* Tasks can be created statically or dynamically, so note
this task had a statically allocated stack in case it is
later deleted. The TCB was allocated dynamically. */
pxNewTCB->ucStaticallyAllocated = tskSTATICALLY_ALLOCATED_STACK_ONLY;
}
#endif
prvInitialiseNewTask( pxTaskDefinition->pvTaskCode,
pxTaskDefinition->pcName,
( uint32_t ) pxTaskDefinition->usStackDepth,
pxTaskDefinition->pvParameters,
pxTaskDefinition->uxPriority,
pxCreatedTask, pxNewTCB,
pxTaskDefinition->xRegions );
prvAddNewTaskToReadyList( pxNewTCB );
xReturn = pdPASS;
}
}
return xReturn;
}
#endif /* portUSING_MPU_WRAPPERS */
/*-----------------------------------------------------------*/
#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
BaseType_t xTaskCreate( TaskFunction_t pxTaskCode,
const char * const pcName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
const configSTACK_DEPTH_TYPE usStackDepth,
void * const pvParameters,
UBaseType_t uxPriority,
TaskHandle_t * const pxCreatedTask )
{
TCB_t *pxNewTCB;
BaseType_t xReturn;
/* If the stack grows down then allocate the stack then the TCB so the stack
does not grow into the TCB. Likewise if the stack grows up then allocate
the TCB then the stack. */
#if( portSTACK_GROWTH > 0 )
{
/* Allocate space for the TCB. Where the memory comes from depends on
the implementation of the port malloc function and whether or not static
allocation is being used. */
pxNewTCB = ( TCB_t * ) pvPortMalloc( sizeof( TCB_t ) );
if( pxNewTCB != NULL )
{
/* Allocate space for the stack used by the task being created.
The base of the stack memory stored in the TCB so the task can
be deleted later if required. */
pxNewTCB->pxStack = ( StackType_t * ) pvPortMalloc( ( ( ( size_t ) usStackDepth ) * sizeof( StackType_t ) ) ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
if( pxNewTCB->pxStack == NULL )
{
/* Could not allocate the stack. Delete the allocated TCB. */
vPortFree( pxNewTCB );
pxNewTCB = NULL;
}
}
}
#else /* portSTACK_GROWTH */
{
StackType_t *pxStack;
/* Allocate space for the stack used by the task being created. */
pxStack = ( StackType_t * ) pvPortMalloc( ( ( ( size_t ) usStackDepth ) * sizeof( StackType_t ) ) ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
if( pxStack != NULL )
{
/* Allocate space for the TCB. */
pxNewTCB = ( TCB_t * ) pvPortMalloc( sizeof( TCB_t ) ); /*lint !e961 MISRA exception as the casts are only redundant for some paths. */
if( pxNewTCB != NULL )
{
/* Store the stack location in the TCB. */
pxNewTCB->pxStack = pxStack;
}
else
{
/* The stack cannot be used as the TCB was not created. Free
it again. */
vPortFree( pxStack );
}
}
else
{
pxNewTCB = NULL;
}
}
#endif /* portSTACK_GROWTH */
if( pxNewTCB != NULL )
{
#if( tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE != 0 ) /*lint !e731 Macro has been consolidated for readability reasons. */
{
/* Tasks can be created statically or dynamically, so note this
task was created dynamically in case it is later deleted. */
pxNewTCB->ucStaticallyAllocated = tskDYNAMICALLY_ALLOCATED_STACK_AND_TCB;
}
#endif /* configSUPPORT_STATIC_ALLOCATION */
prvInitialiseNewTask( pxTaskCode, pcName, ( uint32_t ) usStackDepth, pvParameters, uxPriority, pxCreatedTask, pxNewTCB, NULL );
prvAddNewTaskToReadyList( pxNewTCB );
xReturn = pdPASS;
}
else
{
xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY;
}
return xReturn;
}
#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
/*-----------------------------------------------------------*/
static void prvInitialiseNewTask( TaskFunction_t pxTaskCode,
const char * const pcName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
const uint32_t ulStackDepth,
void * const pvParameters,
UBaseType_t uxPriority,
TaskHandle_t * const pxCreatedTask,
TCB_t *pxNewTCB,
const MemoryRegion_t * const xRegions )
{
StackType_t *pxTopOfStack;
UBaseType_t x;
#if( portUSING_MPU_WRAPPERS == 1 )
/* Should the task be created in privileged mode? */
BaseType_t xRunPrivileged;
if( ( uxPriority & portPRIVILEGE_BIT ) != 0U )
{
xRunPrivileged = pdTRUE;
}
else
{
xRunPrivileged = pdFALSE;
}
uxPriority &= ~portPRIVILEGE_BIT;
#endif /* portUSING_MPU_WRAPPERS == 1 */
/* Avoid dependency on memset() if it is not required. */
#if( tskSET_NEW_STACKS_TO_KNOWN_VALUE == 1 )
{
/* Fill the stack with a known value to assist debugging. */
( void ) memset( pxNewTCB->pxStack, ( int ) tskSTACK_FILL_BYTE, ( size_t ) ulStackDepth * sizeof( StackType_t ) );
}
#endif /* tskSET_NEW_STACKS_TO_KNOWN_VALUE */
/* Calculate the top of stack address. This depends on whether the stack
grows from high memory to low (as per the 80x86) or vice versa.
portSTACK_GROWTH is used to make the result positive or negative as required
by the port. */
#if( portSTACK_GROWTH < 0 )
{
pxTopOfStack = pxNewTCB->pxStack + ( ulStackDepth - ( uint32_t ) 1 );
pxTopOfStack = ( StackType_t * ) ( ( ( portPOINTER_SIZE_TYPE ) pxTopOfStack ) & ( ~( ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK ) ) ); /*lint !e923 MISRA exception. Avoiding casts between pointers and integers is not practical. Size differences accounted for using portPOINTER_SIZE_TYPE type. */
/* Check the alignment of the calculated top of stack is correct. */
configASSERT( ( ( ( portPOINTER_SIZE_TYPE ) pxTopOfStack & ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK ) == 0UL ) );
#if( configRECORD_STACK_HIGH_ADDRESS == 1 )
{
/* Also record the stack's high address, which may assist
debugging. */
pxNewTCB->pxEndOfStack = pxTopOfStack;
}
#endif /* configRECORD_STACK_HIGH_ADDRESS */
}
#else /* portSTACK_GROWTH */
{
pxTopOfStack = pxNewTCB->pxStack;
/* Check the alignment of the stack buffer is correct. */
configASSERT( ( ( ( portPOINTER_SIZE_TYPE ) pxNewTCB->pxStack & ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK ) == 0UL ) );
/* The other extreme of the stack space is required if stack checking is
performed. */
pxNewTCB->pxEndOfStack = pxNewTCB->pxStack + ( ulStackDepth - ( uint32_t ) 1 );
}
#endif /* portSTACK_GROWTH */
/* Store the task name in the TCB. */
for( x = ( UBaseType_t ) 0; x < ( UBaseType_t ) configMAX_TASK_NAME_LEN; x++ )
{
pxNewTCB->pcTaskName[ x ] = pcName[ x ];
/* Don't copy all configMAX_TASK_NAME_LEN if the string is shorter than
configMAX_TASK_NAME_LEN characters just in case the memory after the
string is not accessible (extremely unlikely). */
if( pcName[ x ] == 0x00 )
{
break;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
/* Ensure the name string is terminated in the case that the string length
was greater or equal to configMAX_TASK_NAME_LEN. */
pxNewTCB->pcTaskName[ configMAX_TASK_NAME_LEN - 1 ] = '\0';
/* This is used as an array index so must ensure it's not too large. First
remove the privilege bit if one is present. */
if( uxPriority >= ( UBaseType_t ) configMAX_PRIORITIES )
{
uxPriority = ( UBaseType_t ) configMAX_PRIORITIES - ( UBaseType_t ) 1U;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
pxNewTCB->uxPriority = uxPriority;
#if ( configUSE_MUTEXES == 1 )
{
pxNewTCB->uxBasePriority = uxPriority;
pxNewTCB->uxMutexesHeld = 0;
}
#endif /* configUSE_MUTEXES */
vListInitialiseItem( &( pxNewTCB->xStateListItem ) );
vListInitialiseItem( &( pxNewTCB->xEventListItem ) );
/* Set the pxNewTCB as a link back from the ListItem_t. This is so we can get
back to the containing TCB from a generic item in a list. */
listSET_LIST_ITEM_OWNER( &( pxNewTCB->xStateListItem ), pxNewTCB );
/* Event lists are always in priority order. */
listSET_LIST_ITEM_VALUE( &( pxNewTCB->xEventListItem ), ( TickType_t ) configMAX_PRIORITIES - ( TickType_t ) uxPriority ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
listSET_LIST_ITEM_OWNER( &( pxNewTCB->xEventListItem ), pxNewTCB );
#if ( portCRITICAL_NESTING_IN_TCB == 1 )
{
pxNewTCB->uxCriticalNesting = ( UBaseType_t ) 0U;
}
#endif /* portCRITICAL_NESTING_IN_TCB */
#if ( configUSE_APPLICATION_TASK_TAG == 1 )
{
pxNewTCB->pxTaskTag = NULL;
}
#endif /* configUSE_APPLICATION_TASK_TAG */
#if ( configGENERATE_RUN_TIME_STATS == 1 )
{
pxNewTCB->ulRunTimeCounter = 0UL;
}
#endif /* configGENERATE_RUN_TIME_STATS */
#if ( portUSING_MPU_WRAPPERS == 1 )
{
vPortStoreTaskMPUSettings( &( pxNewTCB->xMPUSettings ), xRegions, pxNewTCB->pxStack, ulStackDepth );
}
#else
{
/* Avoid compiler warning about unreferenced parameter. */
( void ) xRegions;
}
#endif
#if( configNUM_THREAD_LOCAL_STORAGE_POINTERS != 0 )
{
for( x = 0; x < ( UBaseType_t ) configNUM_THREAD_LOCAL_STORAGE_POINTERS; x++ )
{
pxNewTCB->pvThreadLocalStoragePointers[ x ] = NULL;
}
}
#endif
#if ( configUSE_TASK_NOTIFICATIONS == 1 )
{
pxNewTCB->ulNotifiedValue = 0;
pxNewTCB->ucNotifyState = taskNOT_WAITING_NOTIFICATION;
}
#endif
#if ( configUSE_NEWLIB_REENTRANT == 1 )
{
/* Initialise this task's Newlib reent structure. */
_REENT_INIT_PTR( ( &( pxNewTCB->xNewLib_reent ) ) );
}
#endif
#if( INCLUDE_xTaskAbortDelay == 1 )
{
pxNewTCB->ucDelayAborted = pdFALSE;
}
#endif
/* Initialize the TCB stack to look as if the task was already running,