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tasks.c
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tasks.c
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/*
FreeRTOS V8.1.1 - Copyright (C) 2014 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
This file is part of the FreeRTOS distribution.
FreeRTOS is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License (version 2) as published by the
Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
>>! NOTE: The modification to the GPL is included to allow you to !<<
>>! distribute a combined work that includes FreeRTOS without being !<<
>>! obliged to provide the source code for proprietary components !<<
>>! outside of the FreeRTOS kernel. !<<
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. Full license text is available from the following
link: http://www.freertos.org/a00114.html
1 tab == 4 spaces!
***************************************************************************
* *
* Having a problem? Start by reading the FAQ "My application does *
* not run, what could be wrong?" *
* *
* http://www.FreeRTOS.org/FAQHelp.html *
* *
***************************************************************************
http://www.FreeRTOS.org - Documentation, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
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 "StackMacros.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. */
#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 ) */
/* Sanity check the configuration. */
#if configUSE_TICKLESS_IDLE != 0
#if INCLUDE_vTaskSuspend != 1
#error INCLUDE_vTaskSuspend must be set to 1 if configUSE_TICKLESS_IDLE is not set to 0
#endif /* INCLUDE_vTaskSuspend */
#endif /* configUSE_TICKLESS_IDLE */
/*
* Defines the size, in words, of the stack allocated to the idle task.
*/
#define tskIDLE_STACK_SIZE configMINIMAL_STACK_SIZE
#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
/*
* 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 xGenericListItem; /*< 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 )
StackType_t *pxEndOfStack; /*< Points to the end of the stack on architectures where the stack grows up from low memory. */
#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 ( 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
} 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;
/*
* Some kernel aware debuggers require the data the debugger needs access to to
* be global, rather than file scope.
*/
#ifdef portREMOVE_STATIC_QUALIFIER
#define static
#endif
/*lint -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 uxTasksDeleted = ( UBaseType_t ) 0U;
#endif
#if ( INCLUDE_vTaskSuspend == 1 )
PRIVILEGED_DATA static List_t xSuspendedTaskList; /*< Tasks that are currently suspended. */
#endif
#if ( INCLUDE_xTaskGetIdleTaskHandle == 1 )
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. */
#endif
/* Other file private variables. --------------------------------*/
PRIVILEGED_DATA static volatile UBaseType_t uxCurrentNumberOfTasks = ( UBaseType_t ) 0U;
PRIVILEGED_DATA static volatile TickType_t xTickCount = ( TickType_t ) 0U;
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 = portMAX_DELAY;
/* 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 +e956 */
/* Debugging and trace facilities private variables and macros. ------------*/
/*
* 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 )
/*
* Macros used by vListTask to indicate which state a task is in.
*/
#define tskBLOCKED_CHAR ( 'B' )
#define tskREADY_CHAR ( 'R' )
#define tskDELETED_CHAR ( 'D' )
#define tskSUSPENDED_CHAR ( 'S' )
/*-----------------------------------------------------------*/
#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() \
{ \
/* Find the highest priority queue that contains ready tasks. */ \
while( listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxTopReadyPriority ] ) ) ) \
{ \
configASSERT( uxTopReadyPriority ); \
--uxTopReadyPriority; \
} \
\
/* 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[ uxTopReadyPriority ] ) ); \
} /* 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 queue 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 ) ] ) ) == 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 )->xGenericListItem ) )
/*-----------------------------------------------------------*/
/*
* 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
/* 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
/* File private functions. --------------------------------*/
/*
* Utility to ready a TCB for a given task. Mainly just copies the parameters
* into the TCB structure.
*/
static void prvInitialiseTCBVariables( TCB_t * const pxTCB, const char * const pcName, UBaseType_t uxPriority, const MemoryRegion_t * const xRegions, const uint16_t usStackDepth ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
/**
* 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.
*/
static BaseType_t prvTaskIsTaskSuspended( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
/*
* 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( const TickType_t xTimeToWake ) PRIVILEGED_FUNCTION;
/*
* Allocates memory from the heap for a TCB and associated stack. Checks the
* allocation was successful.
*/
static TCB_t *prvAllocateTCBAndStack( const uint16_t usStackDepth, StackType_t * const puxStackBuffer ) 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 prvListTaskWithinSingleList( TaskStatus_t *pxTaskStatusArray, List_t *pxList, eTaskState eState ) 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 );
/*-----------------------------------------------------------*/
BaseType_t xTaskGenericCreate( TaskFunction_t pxTaskCode, const char * const pcName, const uint16_t usStackDepth, void * const pvParameters, UBaseType_t uxPriority, TaskHandle_t * const pxCreatedTask, StackType_t * const puxStackBuffer, const MemoryRegion_t * const xRegions ) /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
{
BaseType_t xReturn;
TCB_t * pxNewTCB;
configASSERT( pxTaskCode );
configASSERT( ( ( uxPriority & ( ~portPRIVILEGE_BIT ) ) < configMAX_PRIORITIES ) );
/* Allocate the memory required by the TCB and stack for the new task,
checking that the allocation was successful. */
pxNewTCB = prvAllocateTCBAndStack( usStackDepth, puxStackBuffer );
if( pxNewTCB != NULL )
{
StackType_t *pxTopOfStack;
#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 */
/* 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 + ( usStackDepth - ( uint16_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 ) );
}
#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 ) );
/* If we want to use stack checking on architectures that use
a positive stack growth direction then we also need to store the
other extreme of the stack space. */
pxNewTCB->pxEndOfStack = pxNewTCB->pxStack + ( usStackDepth - 1 );
}
#endif /* portSTACK_GROWTH */
/* Setup the newly allocated TCB with the initial state of the task. */
prvInitialiseTCBVariables( pxNewTCB, pcName, uxPriority, xRegions, usStackDepth );
/* Initialize the TCB stack to look as if the task was already running,
but had been interrupted by the scheduler. The return address is set
to the start of the task function. Once the stack has been initialised
the top of stack variable is updated. */
#if( portUSING_MPU_WRAPPERS == 1 )
{
pxNewTCB->pxTopOfStack = pxPortInitialiseStack( pxTopOfStack, pxTaskCode, pvParameters, xRunPrivileged );
}
#else /* portUSING_MPU_WRAPPERS */
{
pxNewTCB->pxTopOfStack = pxPortInitialiseStack( pxTopOfStack, pxTaskCode, pvParameters );
}
#endif /* portUSING_MPU_WRAPPERS */
if( ( void * ) pxCreatedTask != NULL )
{
/* Pass the TCB out - in an anonymous way. The calling function/
task can use this as a handle to delete the task later if
required.*/
*pxCreatedTask = ( TaskHandle_t ) pxNewTCB;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
/* Ensure interrupts don't access the task lists while they are being
updated. */
taskENTER_CRITICAL();
{
uxCurrentNumberOfTasks++;
if( pxCurrentTCB == NULL )
{
/* There are no other tasks, or all the other tasks are in
the suspended state - make this the current task. */
pxCurrentTCB = pxNewTCB;
if( uxCurrentNumberOfTasks == ( UBaseType_t ) 1 )
{
/* This is the first task to be created so do the preliminary
initialisation required. We will not recover if this call
fails, but we will report the failure. */
prvInitialiseTaskLists();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
else
{
/* If the scheduler is not already running, make this task the
current task if it is the highest priority task to be created
so far. */
if( xSchedulerRunning == pdFALSE )
{
if( pxCurrentTCB->uxPriority <= uxPriority )
{
pxCurrentTCB = pxNewTCB;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
uxTaskNumber++;
#if ( configUSE_TRACE_FACILITY == 1 )
{
/* Add a counter into the TCB for tracing only. */
pxNewTCB->uxTCBNumber = uxTaskNumber;
}
#endif /* configUSE_TRACE_FACILITY */
traceTASK_CREATE( pxNewTCB );
prvAddTaskToReadyList( pxNewTCB );
xReturn = pdPASS;
portSETUP_TCB( pxNewTCB );
}
taskEXIT_CRITICAL();
}
else
{
xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY;
traceTASK_CREATE_FAILED();
}
if( xReturn == pdPASS )
{
if( xSchedulerRunning != pdFALSE )
{
/* If the created task is of a higher priority than the current task
then it should run now. */
if( pxCurrentTCB->uxPriority < uxPriority )
{
taskYIELD_IF_USING_PREEMPTION();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
return xReturn;
}
/*-----------------------------------------------------------*/
#if ( INCLUDE_vTaskDelete == 1 )
void vTaskDelete( TaskHandle_t xTaskToDelete )
{
TCB_t *pxTCB;
taskENTER_CRITICAL();
{
/* If null is passed in here then it is the calling task that is
being deleted. */
pxTCB = prvGetTCBFromHandle( xTaskToDelete );
/* Remove task from the ready list and place in the termination list.
This will stop the task from be scheduled. The idle task will check
the termination list and free up any memory allocated by the
scheduler for the TCB and stack. */
if( uxListRemove( &( pxTCB->xGenericListItem ) ) == ( UBaseType_t ) 0 )
{
taskRESET_READY_PRIORITY( pxTCB->uxPriority );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
/* Is the task waiting on an event also? */
if( listLIST_ITEM_CONTAINER( &( pxTCB->xEventListItem ) ) != NULL )
{
( void ) uxListRemove( &( pxTCB->xEventListItem ) );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
vListInsertEnd( &xTasksWaitingTermination, &( pxTCB->xGenericListItem ) );
/* Increment the ucTasksDeleted variable so the idle task knows
there is a task that has been deleted and that it should therefore
check the xTasksWaitingTermination list. */
++uxTasksDeleted;
/* Increment the uxTaskNumberVariable also so kernel aware debuggers
can detect that the task lists need re-generating. */
uxTaskNumber++;
traceTASK_DELETE( pxTCB );
}
taskEXIT_CRITICAL();
/* Force a reschedule if it is the currently running task that has just
been deleted. */
if( xSchedulerRunning != pdFALSE )
{
if( pxTCB == pxCurrentTCB )
{
configASSERT( uxSchedulerSuspended == 0 );
/* The pre-delete hook is primarily for the Windows simulator,
in which Windows specific clean up operations are performed,
after which it is not possible to yield away from this task -
hence xYieldPending is used to latch that a context switch is
required. */
portPRE_TASK_DELETE_HOOK( pxTCB, &xYieldPending );
portYIELD_WITHIN_API();
}
else
{
/* Reset the next expected unblock time in case it referred to
the task that has just been deleted. */
taskENTER_CRITICAL();
{
prvResetNextTaskUnblockTime();
}
taskEXIT_CRITICAL();
}
}
}
#endif /* INCLUDE_vTaskDelete */
/*-----------------------------------------------------------*/
#if ( INCLUDE_vTaskDelayUntil == 1 )
void vTaskDelayUntil( TickType_t * const pxPreviousWakeTime, const TickType_t xTimeIncrement )
{
TickType_t xTimeToWake;
BaseType_t xAlreadyYielded, xShouldDelay = pdFALSE;
configASSERT( pxPreviousWakeTime );
configASSERT( ( xTimeIncrement > 0U ) );
configASSERT( uxSchedulerSuspended == 0 );
vTaskSuspendAll();
{
/* Minor optimisation. The tick count cannot change in this
block. */
const TickType_t xConstTickCount = xTickCount;
/* Generate the tick time at which the task wants to wake. */
xTimeToWake = *pxPreviousWakeTime + xTimeIncrement;
if( xConstTickCount < *pxPreviousWakeTime )
{
/* The tick count has overflowed since this function was
lasted called. In this case the only time we should ever
actually delay is if the wake time has also overflowed,
and the wake time is greater than the tick time. When this
is the case it is as if neither time had overflowed. */
if( ( xTimeToWake < *pxPreviousWakeTime ) && ( xTimeToWake > xConstTickCount ) )
{
xShouldDelay = pdTRUE;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
else
{
/* The tick time has not overflowed. In this case we will
delay if either the wake time has overflowed, and/or the
tick time is less than the wake time. */
if( ( xTimeToWake < *pxPreviousWakeTime ) || ( xTimeToWake > xConstTickCount ) )
{
xShouldDelay = pdTRUE;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
/* Update the wake time ready for the next call. */
*pxPreviousWakeTime = xTimeToWake;
if( xShouldDelay != pdFALSE )
{
traceTASK_DELAY_UNTIL();
/* Remove the task from the ready list before adding it to the
blocked list as the same list item is used for both lists. */
if( uxListRemove( &( pxCurrentTCB->xGenericListItem ) ) == ( UBaseType_t ) 0 )
{
/* The current task must be in a ready list, so there is
no need to check, and the port reset macro can be called
directly. */
portRESET_READY_PRIORITY( pxCurrentTCB->uxPriority, uxTopReadyPriority );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
prvAddCurrentTaskToDelayedList( xTimeToWake );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
xAlreadyYielded = xTaskResumeAll();
/* Force a reschedule if xTaskResumeAll has not already done so, we may
have put ourselves to sleep. */
if( xAlreadyYielded == pdFALSE )
{
portYIELD_WITHIN_API();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
#endif /* INCLUDE_vTaskDelayUntil */
/*-----------------------------------------------------------*/
#if ( INCLUDE_vTaskDelay == 1 )
void vTaskDelay( const TickType_t xTicksToDelay )
{
TickType_t xTimeToWake;
BaseType_t xAlreadyYielded = pdFALSE;
/* A delay time of zero just forces a reschedule. */
if( xTicksToDelay > ( TickType_t ) 0U )
{
configASSERT( uxSchedulerSuspended == 0 );
vTaskSuspendAll();
{
traceTASK_DELAY();
/* A task that is removed from the event list while the
scheduler is suspended will not get placed in the ready
list or removed from the blocked list until the scheduler
is resumed.
This task cannot be in an event list as it is the currently
executing task. */
/* Calculate the time to wake - this may overflow but this is
not a problem. */
xTimeToWake = xTickCount + 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. */
if( uxListRemove( &( pxCurrentTCB->xGenericListItem ) ) == ( UBaseType_t ) 0 )
{
/* The current task must be in a ready list, so there is
no need to check, and the port reset macro can be called
directly. */
portRESET_READY_PRIORITY( pxCurrentTCB->uxPriority, uxTopReadyPriority );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
prvAddCurrentTaskToDelayedList( xTimeToWake );
}
xAlreadyYielded = xTaskResumeAll();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
/* Force a reschedule if xTaskResumeAll has not already done so, we may
have put ourselves to sleep. */
if( xAlreadyYielded == pdFALSE )
{
portYIELD_WITHIN_API();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
#endif /* INCLUDE_vTaskDelay */
/*-----------------------------------------------------------*/
#if ( INCLUDE_eTaskGetState == 1 )
eTaskState eTaskGetState( TaskHandle_t xTask )
{
eTaskState eReturn;
List_t *pxStateList;
const TCB_t * const pxTCB = ( TCB_t * ) xTask;
configASSERT( pxTCB );
if( pxTCB == pxCurrentTCB )
{
/* The task calling this function is querying its own state. */
eReturn = eRunning;
}
else
{
taskENTER_CRITICAL();
{
pxStateList = ( List_t * ) listLIST_ITEM_CONTAINER( &( pxTCB->xGenericListItem ) );
}
taskEXIT_CRITICAL();
if( ( pxStateList == pxDelayedTaskList ) || ( pxStateList == pxOverflowDelayedTaskList ) )
{
/* The task being queried is referenced from one of the Blocked
lists. */
eReturn = eBlocked;
}
#if ( INCLUDE_vTaskSuspend == 1 )
else if( pxStateList == &xSuspendedTaskList )
{
/* The task being queried is referenced from the suspended
list. Is it genuinely suspended or is it block
indefinitely? */
if( listLIST_ITEM_CONTAINER( &( pxTCB->xEventListItem ) ) == NULL )
{
eReturn = eSuspended;
}
else
{
eReturn = eBlocked;
}
}
#endif
#if ( INCLUDE_vTaskDelete == 1 )
else if( pxStateList == &xTasksWaitingTermination )
{
/* The task being queried is referenced from the deleted
tasks list. */
eReturn = eDeleted;
}
#endif
else
{
/* If the task is not in any other state, it must be in the
Ready (including pending ready) state. */
eReturn = eReady;
}
}