You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
2041 lines
64 KiB
C
2041 lines
64 KiB
C
/*
|
|
FreeRTOS.org V4.7.0 - Copyright (C) 2003-2007 Richard Barry.
|
|
|
|
This file is part of the FreeRTOS.org distribution.
|
|
|
|
FreeRTOS.org is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
FreeRTOS.org 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. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with FreeRTOS.org; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
|
|
A special exception to the GPL can be applied should you wish to distribute
|
|
a combined work that includes FreeRTOS.org, without being obliged to provide
|
|
the source code for any proprietary components. See the licensing section
|
|
of http://www.FreeRTOS.org for full details of how and when the exception
|
|
can be applied.
|
|
|
|
***************************************************************************
|
|
See http://www.FreeRTOS.org for documentation, latest information, license
|
|
and contact details. Please ensure to read the configuration and relevant
|
|
port sections of the online documentation.
|
|
|
|
Also see http://www.SafeRTOS.com a version that has been certified for use
|
|
in safety critical systems, plus commercial licensing, development and
|
|
support options.
|
|
***************************************************************************
|
|
*/
|
|
|
|
/*
|
|
Changes from V1.00:
|
|
|
|
+ Call to portRESTORE_CONTEXT has been removed. The first context
|
|
switch is now performed within sPortStartScheduler().
|
|
|
|
Changes from V1.01:
|
|
|
|
+ More use of 8bit data types.
|
|
+ Function name prefixes changed where the data type returned has changed.
|
|
+ configUSE_TRACE_FACILITY is no longer defined by default.
|
|
|
|
Changes from V1.2.0
|
|
|
|
+ Introduced ucTopReadyPriority. This tracks the highest priority ready
|
|
queue that contains a valid TCB and thus makes the context switch
|
|
slightly faster.
|
|
|
|
+ prvAddTaskToReadyQueue() has been made a macro.
|
|
|
|
Changes from V1.2.6
|
|
|
|
+ Added conditional compilation directives.
|
|
+ Extended API.
|
|
+ Rearranged function order.
|
|
+ Creating a task now causes a context switch if the task being created
|
|
has a higher priority than the calling task - assuming the kernel is
|
|
running.
|
|
+ vTaskDelete() now only causes a context switch if the calling task is
|
|
the task being deleted.
|
|
|
|
Changes from V2.0.0
|
|
|
|
+ Allow the type of the tick count to be 16 or 32 bits.
|
|
+ Introduce xPendingReadyList feature to allow the time interrupts have to
|
|
be disabled to be minimised.
|
|
+ Remove the #if( INCLUDE_vTaskSuspendAll ) statements. vTaskSuspendAll()
|
|
is now always included as it is used by the scheduler itself.
|
|
|
|
Changes from V2.1.0
|
|
|
|
+ Bug fix - pxCurrentTCB is now initialised before the call to
|
|
prvInitializeTaskLists(). Previously pxCurrentTCB could be accessed
|
|
while null.
|
|
|
|
Changed from V2.1.1
|
|
|
|
+ Change to where lStackSize is declared within sTaskCreate() to prevent
|
|
compiler warnings with 8051 port.
|
|
|
|
Changes from V2.2.0
|
|
|
|
+ Explicit use of 'signed' qualifier on portCHAR types added.
|
|
+ Changed odd calculation of initial pxTopOfStack value when
|
|
portSTACK_GROWTH < 0.
|
|
+ Removed pcVersionNumber definition.
|
|
|
|
Changes from V2.5.3
|
|
|
|
+ cTaskResumeAll() modified to ensure it can be called prior to the task
|
|
lists being initialised.
|
|
|
|
Changes from V2.5.5
|
|
|
|
+ Added API function vTaskDelayUntil().
|
|
+ Added INCLUDE_vTaskDelay conditional compilation.
|
|
|
|
Changes from V2.6.0
|
|
|
|
+ Updated the vWriteTraceToBuffer macro to always be 4 byte aligned so it
|
|
can be used on ARM architectures.
|
|
+ tskMAX_TASK_NAME_LEN definition replaced with the port specific
|
|
configMAX_TASK_NAME_LEN definition.
|
|
+ Removed the call to strcpy when copying across the task name into the
|
|
TCB.
|
|
+ Added ucTasksDeleted variable to prevent vTaskSuspendAll() being called
|
|
too often in the idle task.
|
|
|
|
Changes between V3.0.0 and V2.6.1
|
|
|
|
+ When resuming the scheduler a yield is performed if either a tick has
|
|
been missed, or a task is moved from the pending ready list into a ready
|
|
list. Previously a yield was not performed on this second condition.
|
|
+ Introduced the type portBASE_TYPE. This necessitates several API
|
|
changes.
|
|
+ Removed the sUsingPreemption variable. The constant defined in
|
|
portmacro.h is now used directly.
|
|
+ The idle task can now include an optional hook function - and no longer
|
|
completes its time slice if other tasks with equal priority to it are
|
|
ready to run.
|
|
+ See the FreeRTOS.org documentation for more information on V2.x.x to
|
|
V3.x.x modifications.
|
|
|
|
Changes from V3.1.1
|
|
|
|
+ Modified vTaskPrioritySet() and vTaskResume() to allow these functions to
|
|
be called while the scheduler is suspended.
|
|
+ Corrected the task ordering within event lists.
|
|
|
|
Changes from V3.2.0
|
|
|
|
+ Added function xTaskGetCurrentTaskHandle().
|
|
|
|
Changes from V3.2.4
|
|
|
|
+ Changed the volatile declarations on some variables to reflect the
|
|
changes to the list definitions.
|
|
+ Changed the order of the TCB definition so there is commonality between
|
|
the task control block and a co-routine control block.
|
|
+ Allow the scheduler to be started even if no tasks other than the idle
|
|
task has been created. This allows co-routines to run even when no tasks
|
|
have been created.
|
|
+ The need for a context switch is now signalled if a task woken by an
|
|
event has a priority greater or equal to the currently running task.
|
|
Previously this was only greater than.
|
|
|
|
Changes from V4.0.0
|
|
|
|
+ Added the xMissedYield handling.
|
|
|
|
Changes from V4.0.1
|
|
|
|
+ The function vTaskList() now suspends the scheduler rather than disabling
|
|
interrupts during the creation of the task list.
|
|
+ Allow a task to delete itself by passing in its own handle. Previously
|
|
this could only be done by passing in NULL.
|
|
+ The tick hook function is now called only within a tick isr. Previously
|
|
it was also called when the tick function was called during the scheduler
|
|
unlocking process.
|
|
|
|
Changes from V4.0.3
|
|
|
|
+ Extra checks have been placed in vTaskPrioritySet() to avoid unnecessary
|
|
yields.
|
|
|
|
Changed from V4.0.4
|
|
|
|
+ Bug fix: The 'value' of the event list item is updated when the priority
|
|
of a task is changed. Previously only the priority of the TCB itself was
|
|
changed.
|
|
+ When resuming a task a check is first made to see if the task is actually
|
|
suspended.
|
|
+ vTaskPrioritySet() and vTaskResume() no longer use the event list item.
|
|
This has not been necessary since V4.0.1 when the xMissedYield handling
|
|
was added.
|
|
+ Implement xTaskResumeFromISR().
|
|
|
|
Changes from V4.0.5
|
|
|
|
+ Added utility functions and xOverflowCount variable to facilitate the
|
|
queue.c changes.
|
|
|
|
Changes from V4.1.2
|
|
|
|
+ Tasks that block on events with a timeout of portMAX_DELAY are now
|
|
blocked indefinitely if configINCLUDE_vTaskSuspend is defined.
|
|
Previously portMAX_DELAY was just the longest block time possible.
|
|
|
|
Changes from V4.1.3
|
|
|
|
+ Very small change made to xTaskCheckForTimeout() as a result of the
|
|
SafeRTOS testing. This corrects the case where the function can return an
|
|
invalid value - but only in an extremely unlikely scenario.
|
|
|
|
Changes since V4.3.1:
|
|
|
|
+ Added xTaskGetSchedulerState() function.
|
|
+ Added prvIsTaskSuspended() to take into account the Occurrence of
|
|
vTaskResume() or vTaskResumeFromISR() being called passing in the
|
|
handle of a task that appears in the Suspended list only because it
|
|
is blocked on an event without a timeout being specified.
|
|
+ Updated xTaskCheckForTimeout() to take into account that tasks blocked
|
|
using the Suspended list should never time out.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "FreeRTOS.h"
|
|
#include "task.h"
|
|
|
|
/*
|
|
* Macro to define the amount of stack available to the idle task.
|
|
*/
|
|
#define tskIDLE_STACK_SIZE configMINIMAL_STACK_SIZE
|
|
|
|
|
|
/*
|
|
* Default a definitions for backwards compatibility with old
|
|
* portmacro.h files.
|
|
*/
|
|
#ifndef configMAX_TASK_NAME_LEN
|
|
#define configMAX_TASK_NAME_LEN 16
|
|
#endif
|
|
|
|
#ifndef configIDLE_SHOULD_YIELD
|
|
#define configIDLE_SHOULD_YIELD 1
|
|
#endif
|
|
|
|
#if configMAX_TASK_NAME_LEN < 1
|
|
#undef configMAX_TASK_NAME_LEN
|
|
#define configMAX_TASK_NAME_LEN 1
|
|
#endif
|
|
|
|
#ifndef INCLUDE_xTaskResumeFromISR
|
|
#define INCLUDE_xTaskResumeFromISR 1
|
|
#endif
|
|
|
|
#ifndef INCLUDE_xTaskGetSchedulerState
|
|
#define INCLUDE_xTaskGetSchedulerState 0
|
|
#endif
|
|
|
|
/*
|
|
* Task control block. A task control block (TCB) is allocated to each task,
|
|
* and stores the context of the task.
|
|
*/
|
|
typedef struct tskTaskControlBlock
|
|
{
|
|
volatile portSTACK_TYPE *pxTopOfStack; /*< Points to the location of the last item placed on the tasks stack. THIS MUST BE THE FIRST MEMBER OF THE STRUCT. */
|
|
xListItem xGenericListItem; /*< List item used to place the TCB in ready and blocked queues. */
|
|
xListItem xEventListItem; /*< List item used to place the TCB in event lists. */
|
|
unsigned portBASE_TYPE uxPriority; /*< The priority of the task where 0 is the lowest priority. */
|
|
portSTACK_TYPE *pxStack; /*< Points to the start of the stack. */
|
|
signed portCHAR pcTaskName[ configMAX_TASK_NAME_LEN ];/*< Descriptive name given to the task when created. Facilitates debugging only. */
|
|
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
unsigned portBASE_TYPE uxTCBNumber; /*< This is used for tracing the scheduler and making debugging easier only. */
|
|
#endif
|
|
|
|
#if ( configUSE_MUTEXES == 1 )
|
|
unsigned portBASE_TYPE uxBasePriority;
|
|
#endif
|
|
|
|
} tskTCB;
|
|
|
|
/*lint -e956 */
|
|
|
|
tskTCB * volatile pxCurrentTCB = NULL;
|
|
|
|
/* Lists for ready and blocked tasks. --------------------*/
|
|
|
|
static xList pxReadyTasksLists[ configMAX_PRIORITIES ]; /*< Prioritised ready tasks. */
|
|
static xList xDelayedTaskList1; /*< Delayed tasks. */
|
|
static xList xDelayedTaskList2; /*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */
|
|
static xList * volatile pxDelayedTaskList; /*< Points to the delayed task list currently being used. */
|
|
static xList * volatile pxOverflowDelayedTaskList; /*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */
|
|
static xList xPendingReadyList; /*< Tasks that have been readied while the scheduler was suspended. They will be moved to the ready queue when the scheduler is resumed. */
|
|
|
|
#if ( INCLUDE_vTaskDelete == 1 )
|
|
|
|
static volatile xList xTasksWaitingTermination; /*< Tasks that have been deleted - but the their memory not yet freed. */
|
|
static volatile unsigned portBASE_TYPE uxTasksDeleted = ( unsigned portBASE_TYPE ) 0;
|
|
|
|
#endif
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
|
|
static xList xSuspendedTaskList; /*< Tasks that are currently suspended. */
|
|
|
|
#endif
|
|
|
|
/* File private variables. --------------------------------*/
|
|
static volatile unsigned portBASE_TYPE uxCurrentNumberOfTasks = ( unsigned portBASE_TYPE ) 0;
|
|
static volatile portTickType xTickCount = ( portTickType ) 0;
|
|
static unsigned portBASE_TYPE uxTopUsedPriority = tskIDLE_PRIORITY;
|
|
static volatile unsigned portBASE_TYPE uxTopReadyPriority = tskIDLE_PRIORITY;
|
|
static volatile signed portBASE_TYPE xSchedulerRunning = pdFALSE;
|
|
static volatile unsigned portBASE_TYPE uxSchedulerSuspended = ( unsigned portBASE_TYPE ) pdFALSE;
|
|
static volatile unsigned portBASE_TYPE uxMissedTicks = ( unsigned portBASE_TYPE ) 0;
|
|
static volatile portBASE_TYPE xMissedYield = ( portBASE_TYPE ) pdFALSE;
|
|
static volatile portBASE_TYPE xNumOfOverflows = ( portBASE_TYPE ) 0;
|
|
/* 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 ( 0xa5 )
|
|
|
|
/*
|
|
* Macros used by vListTask to indicate which state a task is in.
|
|
*/
|
|
#define tskBLOCKED_CHAR ( ( signed portCHAR ) 'B' )
|
|
#define tskREADY_CHAR ( ( signed portCHAR ) 'R' )
|
|
#define tskDELETED_CHAR ( ( signed portCHAR ) 'D' )
|
|
#define tskSUSPENDED_CHAR ( ( signed portCHAR ) 'S' )
|
|
|
|
/*
|
|
* Macros and private variables used by the trace facility.
|
|
*/
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
|
|
#define tskSIZE_OF_EACH_TRACE_LINE ( ( unsigned portLONG ) ( sizeof( unsigned portLONG ) + sizeof( unsigned portLONG ) ) )
|
|
static volatile signed portCHAR * volatile pcTraceBuffer;
|
|
static signed portCHAR *pcTraceBufferStart;
|
|
static signed portCHAR *pcTraceBufferEnd;
|
|
static signed portBASE_TYPE xTracing = pdFALSE;
|
|
|
|
#endif
|
|
|
|
/*
|
|
* Macro that writes a trace of scheduler activity to a buffer. This trace
|
|
* shows which task is running when and is very useful as a debugging tool.
|
|
* As this macro is called each context switch it is a good idea to undefine
|
|
* it if not using the facility.
|
|
*/
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
|
|
#define vWriteTraceToBuffer() \
|
|
{ \
|
|
if( xTracing ) \
|
|
{ \
|
|
static unsigned portBASE_TYPE uxPreviousTask = 255; \
|
|
\
|
|
if( uxPreviousTask != pxCurrentTCB->uxTCBNumber ) \
|
|
{ \
|
|
if( ( pcTraceBuffer + tskSIZE_OF_EACH_TRACE_LINE ) < pcTraceBufferEnd ) \
|
|
{ \
|
|
uxPreviousTask = pxCurrentTCB->uxTCBNumber; \
|
|
*( unsigned portLONG * ) pcTraceBuffer = ( unsigned portLONG ) xTickCount; \
|
|
pcTraceBuffer += sizeof( unsigned portLONG ); \
|
|
*( unsigned portLONG * ) pcTraceBuffer = ( unsigned portLONG ) uxPreviousTask; \
|
|
pcTraceBuffer += sizeof( unsigned portLONG ); \
|
|
} \
|
|
else \
|
|
{ \
|
|
xTracing = pdFALSE; \
|
|
} \
|
|
} \
|
|
} \
|
|
}
|
|
|
|
#else
|
|
|
|
#define vWriteTraceToBuffer()
|
|
|
|
#endif
|
|
|
|
|
|
/*
|
|
* Place the task represented by pxTCB into the appropriate ready queue for
|
|
* the task. It is inserted at the end of the list. One quirk of this is
|
|
* that if the task being inserted is at the same priority as the currently
|
|
* executing task, then it will only be rescheduled after the currently
|
|
* executing task has been rescheduled.
|
|
*/
|
|
#define prvAddTaskToReadyQueue( pxTCB ) \
|
|
{ \
|
|
if( pxTCB->uxPriority > uxTopReadyPriority ) \
|
|
{ \
|
|
uxTopReadyPriority = pxTCB->uxPriority; \
|
|
} \
|
|
vListInsertEnd( ( xList * ) &( pxReadyTasksLists[ pxTCB->uxPriority ] ), &( pxTCB->xGenericListItem ) ); \
|
|
}
|
|
|
|
/*
|
|
* Macro that looks at the list of tasks that are currently delayed to see if
|
|
* any require waking.
|
|
*
|
|
* Tasks are stored in the queue in the order of their wake time - meaning
|
|
* once one tasks has been found whose timer has not expired we need not look
|
|
* any further down the list.
|
|
*/
|
|
#define prvCheckDelayedTasks() \
|
|
{ \
|
|
register tskTCB *pxTCB; \
|
|
\
|
|
while( ( pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxDelayedTaskList ) ) != NULL ) \
|
|
{ \
|
|
if( xTickCount < listGET_LIST_ITEM_VALUE( &( pxTCB->xGenericListItem ) ) ) \
|
|
{ \
|
|
break; \
|
|
} \
|
|
vListRemove( &( pxTCB->xGenericListItem ) ); \
|
|
/* Is the task waiting on an event also? */ \
|
|
if( pxTCB->xEventListItem.pvContainer ) \
|
|
{ \
|
|
vListRemove( &( pxTCB->xEventListItem ) ); \
|
|
} \
|
|
prvAddTaskToReadyQueue( pxTCB ); \
|
|
} \
|
|
}
|
|
|
|
/*
|
|
* Several functions take an xTaskHandle 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 ) ? ( tskTCB * ) pxCurrentTCB : ( tskTCB * ) pxHandle )
|
|
|
|
|
|
/* File private functions. --------------------------------*/
|
|
|
|
/*
|
|
* Utility to ready a TCB for a given task. Mainly just copies the parameters
|
|
* into the TCB structure.
|
|
*/
|
|
static void prvInitialiseTCBVariables( tskTCB *pxTCB, const signed portCHAR * const pcName, unsigned portBASE_TYPE uxPriority );
|
|
|
|
/*
|
|
* 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 );
|
|
|
|
/*
|
|
* 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 ) || ( INCLUDE_vTaskCleanUpResources == 1 ) )
|
|
static void prvDeleteTCB( tskTCB *pxTCB );
|
|
#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 );
|
|
|
|
/*
|
|
* Allocates memory from the heap for a TCB and associated stack. Checks the
|
|
* allocation was successful.
|
|
*/
|
|
static tskTCB *prvAllocateTCBAndStack( unsigned portSHORT usStackDepth );
|
|
|
|
/*
|
|
* Called from vTaskList. vListTasks details all the tasks currently under
|
|
* control of the scheduler. The tasks may be in one of a number of lists.
|
|
* prvListTaskWithinSingleList accepts a list and details the tasks from
|
|
* within just that list.
|
|
*
|
|
* THIS FUNCTION IS INTENDED FOR DEBUGGING ONLY, AND SHOULD NOT BE CALLED FROM
|
|
* NORMAL APPLICATION CODE.
|
|
*/
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
|
|
static void prvListTaskWithinSingleList( const signed portCHAR *pcWriteBuffer, xList *pxList, signed portCHAR cStatus );
|
|
|
|
#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 )
|
|
|
|
unsigned portSHORT usTaskCheckFreeStackSpace( const unsigned portCHAR * pucStackByte );
|
|
|
|
#endif
|
|
|
|
/*
|
|
* Checks that a task being resumed (unsuspended) is actually in the Suspended
|
|
* state.
|
|
*/
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
|
|
static portBASE_TYPE prvIsTaskSuspended( const tskTCB * const pxTCB );
|
|
|
|
#endif
|
|
|
|
/*lint +e956 */
|
|
|
|
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------
|
|
* TASK CREATION API documented in task.h
|
|
*----------------------------------------------------------*/
|
|
|
|
signed portBASE_TYPE xTaskCreate( pdTASK_CODE pvTaskCode, const signed portCHAR * const pcName, unsigned portSHORT usStackDepth, void *pvParameters, unsigned portBASE_TYPE uxPriority, xTaskHandle *pxCreatedTask )
|
|
{
|
|
signed portBASE_TYPE xReturn;
|
|
tskTCB * pxNewTCB;
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
static unsigned portBASE_TYPE uxTaskNumber = 0; /*lint !e956 Static is deliberate - this is guarded before use. */
|
|
#endif
|
|
|
|
/* Allocate the memory required by the TCB and stack for the new task.
|
|
checking that the allocation was successful. */
|
|
pxNewTCB = prvAllocateTCBAndStack( usStackDepth );
|
|
|
|
if( pxNewTCB != NULL )
|
|
{
|
|
portSTACK_TYPE *pxTopOfStack;
|
|
|
|
/* Setup the newly allocated TCB with the initial state of the task. */
|
|
prvInitialiseTCBVariables( pxNewTCB, pcName, uxPriority );
|
|
|
|
/* Calculate the top of stack address. This depends on whether the
|
|
stack grows from high memory to low (as per the 80x86) or visa 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 - 1 );
|
|
}
|
|
#else
|
|
{
|
|
pxTopOfStack = pxNewTCB->pxStack;
|
|
}
|
|
#endif
|
|
|
|
/* 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. */
|
|
pxNewTCB->pxTopOfStack = pxPortInitialiseStack( pxTopOfStack, pvTaskCode, pvParameters );
|
|
|
|
/* We are going to manipulate the task queues to add this task to a
|
|
ready list, so must make sure no interrupts occur. */
|
|
portENTER_CRITICAL();
|
|
{
|
|
uxCurrentNumberOfTasks++;
|
|
if( uxCurrentNumberOfTasks == ( unsigned portBASE_TYPE ) 1 )
|
|
{
|
|
/* As this is the first task it must also be the current task. */
|
|
pxCurrentTCB = pxNewTCB;
|
|
|
|
/* 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
|
|
{
|
|
/* 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;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Remember the top priority to make context switching faster. Use
|
|
the priority in pxNewTCB as this has been capped to a valid value. */
|
|
if( pxNewTCB->uxPriority > uxTopUsedPriority )
|
|
{
|
|
uxTopUsedPriority = pxNewTCB->uxPriority;
|
|
}
|
|
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
{
|
|
/* Add a counter into the TCB for tracing only. */
|
|
pxNewTCB->uxTCBNumber = uxTaskNumber;
|
|
uxTaskNumber++;
|
|
}
|
|
#endif
|
|
|
|
prvAddTaskToReadyQueue( pxNewTCB );
|
|
|
|
xReturn = pdPASS;
|
|
}
|
|
portEXIT_CRITICAL();
|
|
}
|
|
else
|
|
{
|
|
xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY;
|
|
}
|
|
|
|
if( xReturn == pdPASS )
|
|
{
|
|
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 = ( xTaskHandle ) pxNewTCB;
|
|
}
|
|
|
|
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();
|
|
}
|
|
}
|
|
}
|
|
|
|
return xReturn;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskDelete == 1 )
|
|
|
|
void vTaskDelete( xTaskHandle pxTaskToDelete )
|
|
{
|
|
tskTCB *pxTCB;
|
|
|
|
taskENTER_CRITICAL();
|
|
{
|
|
/* Ensure a yield is performed if the current task is being
|
|
deleted. */
|
|
if( pxTaskToDelete == pxCurrentTCB )
|
|
{
|
|
pxTaskToDelete = NULL;
|
|
}
|
|
|
|
/* If null is passed in here then we are deleting ourselves. */
|
|
pxTCB = prvGetTCBFromHandle( pxTaskToDelete );
|
|
|
|
/* 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. */
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
|
|
/* Is the task waiting on an event also? */
|
|
if( pxTCB->xEventListItem.pvContainer )
|
|
{
|
|
vListRemove( &( pxTCB->xEventListItem ) );
|
|
}
|
|
|
|
vListInsertEnd( ( xList * ) &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;
|
|
}
|
|
taskEXIT_CRITICAL();
|
|
|
|
/* Force a reschedule if we have just deleted the current task. */
|
|
if( xSchedulerRunning != pdFALSE )
|
|
{
|
|
if( ( void * ) pxTaskToDelete == NULL )
|
|
{
|
|
taskYIELD();
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------
|
|
* TASK CONTROL API documented in task.h
|
|
*----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskDelayUntil == 1 )
|
|
|
|
void vTaskDelayUntil( portTickType * const pxPreviousWakeTime, portTickType xTimeIncrement )
|
|
{
|
|
portTickType xTimeToWake;
|
|
portBASE_TYPE xAlreadyYielded, xShouldDelay = pdFALSE;
|
|
|
|
vTaskSuspendAll();
|
|
{
|
|
/* Generate the tick time at which the task wants to wake. */
|
|
xTimeToWake = *pxPreviousWakeTime + xTimeIncrement;
|
|
|
|
if( xTickCount < *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 > xTickCount ) )
|
|
{
|
|
xShouldDelay = pdTRUE;
|
|
}
|
|
}
|
|
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 > xTickCount ) )
|
|
{
|
|
xShouldDelay = pdTRUE;
|
|
}
|
|
}
|
|
|
|
/* Update the wake time ready for the next call. */
|
|
*pxPreviousWakeTime = xTimeToWake;
|
|
|
|
if( xShouldDelay )
|
|
{
|
|
/* 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. */
|
|
vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
|
|
/* The list item will be inserted in wake time order. */
|
|
listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
|
|
|
|
if( xTimeToWake < xTickCount )
|
|
{
|
|
/* Wake time has overflowed. Place this item in the
|
|
overflow list. */
|
|
vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
else
|
|
{
|
|
/* The wake time has not overflowed, so we can use the
|
|
current block list. */
|
|
vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
}
|
|
}
|
|
xAlreadyYielded = xTaskResumeAll();
|
|
|
|
/* Force a reschedule if xTaskResumeAll has not already done so, we may
|
|
have put ourselves to sleep. */
|
|
if( !xAlreadyYielded )
|
|
{
|
|
taskYIELD();
|
|
}
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskDelay == 1 )
|
|
|
|
void vTaskDelay( portTickType xTicksToDelay )
|
|
{
|
|
portTickType xTimeToWake;
|
|
signed portBASE_TYPE xAlreadyYielded = pdFALSE;
|
|
|
|
/* A delay time of zero just forces a reschedule. */
|
|
if( xTicksToDelay > ( portTickType ) 0 )
|
|
{
|
|
vTaskSuspendAll();
|
|
{
|
|
/* 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. */
|
|
vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
|
|
/* The list item will be inserted in wake time order. */
|
|
listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
|
|
|
|
if( xTimeToWake < xTickCount )
|
|
{
|
|
/* Wake time has overflowed. Place this item in the
|
|
overflow list. */
|
|
vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
else
|
|
{
|
|
/* The wake time has not overflowed, so we can use the
|
|
current block list. */
|
|
vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
}
|
|
xAlreadyYielded = xTaskResumeAll();
|
|
}
|
|
|
|
/* Force a reschedule if xTaskResumeAll has not already done so, we may
|
|
have put ourselves to sleep. */
|
|
if( !xAlreadyYielded )
|
|
{
|
|
taskYIELD();
|
|
}
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_uxTaskPriorityGet == 1 )
|
|
|
|
unsigned portBASE_TYPE uxTaskPriorityGet( xTaskHandle pxTask )
|
|
{
|
|
tskTCB *pxTCB;
|
|
unsigned portBASE_TYPE uxReturn;
|
|
|
|
taskENTER_CRITICAL();
|
|
{
|
|
/* If null is passed in here then we are changing the
|
|
priority of the calling function. */
|
|
pxTCB = prvGetTCBFromHandle( pxTask );
|
|
uxReturn = pxTCB->uxPriority;
|
|
}
|
|
taskEXIT_CRITICAL();
|
|
|
|
return uxReturn;
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskPrioritySet == 1 )
|
|
|
|
void vTaskPrioritySet( xTaskHandle pxTask, unsigned portBASE_TYPE uxNewPriority )
|
|
{
|
|
tskTCB *pxTCB;
|
|
unsigned portBASE_TYPE uxCurrentPriority, xYieldRequired = pdFALSE;
|
|
|
|
/* Ensure the new priority is valid. */
|
|
if( uxNewPriority >= configMAX_PRIORITIES )
|
|
{
|
|
uxNewPriority = configMAX_PRIORITIES - 1;
|
|
}
|
|
|
|
taskENTER_CRITICAL();
|
|
{
|
|
/* If null is passed in here then we are changing the
|
|
priority of the calling function. */
|
|
pxTCB = prvGetTCBFromHandle( pxTask );
|
|
|
|
#if ( configUSE_MUTEXES == 1 )
|
|
{
|
|
uxCurrentPriority = pxTCB->uxBasePriority;
|
|
}
|
|
#else
|
|
{
|
|
uxCurrentPriority = pxTCB->uxPriority;
|
|
}
|
|
#endif
|
|
|
|
if( uxCurrentPriority != uxNewPriority )
|
|
{
|
|
/* The priority change may have readied a task of higher
|
|
priority than the calling task. */
|
|
if( uxNewPriority > uxCurrentPriority )
|
|
{
|
|
if( pxTask != NULL )
|
|
{
|
|
/* The priority of another task is being raised. If we
|
|
were raising the priority of the currently running task
|
|
there would be no need to switch as it must have already
|
|
been the highest priority task. */
|
|
xYieldRequired = pdTRUE;
|
|
}
|
|
}
|
|
else if( pxTask == NULL )
|
|
{
|
|
/* Setting our own priority down means there may now be another
|
|
task of higher priority that is ready to execute. */
|
|
xYieldRequired = pdTRUE;
|
|
}
|
|
|
|
|
|
|
|
#if ( configUSE_MUTEXES == 1 )
|
|
{
|
|
/* Only change the priority being used if the task is not
|
|
currently using an inherited priority. */
|
|
if( pxTCB->uxBasePriority == pxTCB->uxPriority )
|
|
{
|
|
pxTCB->uxPriority = uxNewPriority;
|
|
}
|
|
|
|
/* The base priority gets set whatever. */
|
|
pxTCB->uxBasePriority = uxNewPriority;
|
|
}
|
|
#else
|
|
{
|
|
pxTCB->uxPriority = uxNewPriority;
|
|
}
|
|
#endif
|
|
|
|
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), ( configMAX_PRIORITIES - ( portTickType ) uxNewPriority ) );
|
|
|
|
/* If the task is in the blocked or suspended list we need do
|
|
nothing more than change it's priority variable. However, if
|
|
the task is in a ready list it needs to be removed and placed
|
|
in the queue appropriate to its new priority. */
|
|
if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ uxCurrentPriority ] ), &( pxTCB->xGenericListItem ) ) )
|
|
{
|
|
/* The task is currently in its ready list - remove before adding
|
|
it to it's new ready list. As we are in a critical section we
|
|
can do this even if the scheduler is suspended. */
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
prvAddTaskToReadyQueue( pxTCB );
|
|
}
|
|
|
|
if( xYieldRequired == pdTRUE )
|
|
{
|
|
taskYIELD();
|
|
}
|
|
}
|
|
}
|
|
taskEXIT_CRITICAL();
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
|
|
void vTaskSuspend( xTaskHandle pxTaskToSuspend )
|
|
{
|
|
tskTCB *pxTCB;
|
|
|
|
taskENTER_CRITICAL();
|
|
{
|
|
/* Ensure a yield is performed if the current task is being
|
|
suspended. */
|
|
if( pxTaskToSuspend == pxCurrentTCB )
|
|
{
|
|
pxTaskToSuspend = NULL;
|
|
}
|
|
|
|
/* If null is passed in here then we are suspending ourselves. */
|
|
pxTCB = prvGetTCBFromHandle( pxTaskToSuspend );
|
|
|
|
/* Remove task from the ready/delayed list and place in the suspended list. */
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
|
|
/* Is the task waiting on an event also? */
|
|
if( pxTCB->xEventListItem.pvContainer )
|
|
{
|
|
vListRemove( &( pxTCB->xEventListItem ) );
|
|
}
|
|
|
|
vListInsertEnd( ( xList * ) &xSuspendedTaskList, &( pxTCB->xGenericListItem ) );
|
|
}
|
|
taskEXIT_CRITICAL();
|
|
|
|
/* We may have just suspended the current task. */
|
|
if( ( void * ) pxTaskToSuspend == NULL )
|
|
{
|
|
taskYIELD();
|
|
}
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
|
|
static portBASE_TYPE prvIsTaskSuspended( const tskTCB * const pxTCB )
|
|
{
|
|
portBASE_TYPE xReturn = pdFALSE;
|
|
|
|
/* Is the task we are attempting to resume actually in the
|
|
suspended list? */
|
|
if( listIS_CONTAINED_WITHIN( &xSuspendedTaskList, &( pxTCB->xGenericListItem ) ) != pdFALSE )
|
|
{
|
|
/* Has the task already been resumed from within an ISR? */
|
|
if( listIS_CONTAINED_WITHIN( &xPendingReadyList, &( pxTCB->xEventListItem ) ) != pdTRUE )
|
|
{
|
|
/* Is it in the suspended list because it is in the
|
|
Suspended state? It is possible to be in the suspended
|
|
list because it is blocked on a task with no timeout
|
|
specified. */
|
|
if( listIS_CONTAINED_WITHIN( NULL, &( pxTCB->xEventListItem ) ) == pdTRUE )
|
|
{
|
|
xReturn = pdTRUE;
|
|
}
|
|
}
|
|
}
|
|
|
|
return xReturn;
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
|
|
void vTaskResume( xTaskHandle pxTaskToResume )
|
|
{
|
|
tskTCB *pxTCB;
|
|
|
|
/* Remove the task from whichever list it is currently in, and place
|
|
it in the ready list. */
|
|
pxTCB = ( tskTCB * ) pxTaskToResume;
|
|
|
|
/* The parameter cannot be NULL as it is impossible to resume the
|
|
currently executing task. */
|
|
if( pxTCB != NULL )
|
|
{
|
|
taskENTER_CRITICAL();
|
|
{
|
|
if( prvIsTaskSuspended( pxTCB ) == pdTRUE )
|
|
{
|
|
/* As we are in a critical section we can access the ready
|
|
lists even if the scheduler is suspended. */
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
prvAddTaskToReadyQueue( pxTCB );
|
|
|
|
/* We may have just resumed a higher priority task. */
|
|
if( pxTCB->uxPriority >= pxCurrentTCB->uxPriority )
|
|
{
|
|
/* This yield may not cause the task just resumed to run, but
|
|
will leave the lists in the correct state for the next yield. */
|
|
taskYIELD();
|
|
}
|
|
}
|
|
}
|
|
taskEXIT_CRITICAL();
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( ( INCLUDE_xTaskResumeFromISR == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
|
|
|
|
portBASE_TYPE xTaskResumeFromISR( xTaskHandle pxTaskToResume )
|
|
{
|
|
portBASE_TYPE xYieldRequired = pdFALSE;
|
|
tskTCB *pxTCB;
|
|
|
|
pxTCB = ( tskTCB * ) pxTaskToResume;
|
|
|
|
if( prvIsTaskSuspended( pxTCB ) == pdTRUE )
|
|
{
|
|
if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
|
|
{
|
|
xYieldRequired = ( pxTCB->uxPriority >= pxCurrentTCB->uxPriority );
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
prvAddTaskToReadyQueue( pxTCB );
|
|
}
|
|
else
|
|
{
|
|
/* We cannot access the delayed or ready lists, so will hold this
|
|
task pending until the scheduler is resumed, at which point a
|
|
yield will be performed if necessary. */
|
|
vListInsertEnd( ( xList * ) &( xPendingReadyList ), &( pxTCB->xEventListItem ) );
|
|
}
|
|
}
|
|
|
|
return xYieldRequired;
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------
|
|
* PUBLIC SCHEDULER CONTROL documented in task.h
|
|
*----------------------------------------------------------*/
|
|
|
|
|
|
void vTaskStartScheduler( void )
|
|
{
|
|
portBASE_TYPE xReturn;
|
|
|
|
/* Add the idle task at the lowest priority. */
|
|
xReturn = xTaskCreate( prvIdleTask, ( signed portCHAR * ) "IDLE", tskIDLE_STACK_SIZE, ( void * ) NULL, tskIDLE_PRIORITY, ( xTaskHandle * ) NULL );
|
|
|
|
if( xReturn == pdPASS )
|
|
{
|
|
/* Interrupts are turned off here, to ensure a tick does not occur
|
|
before or during the call to xPortStartScheduler(). The stacks of
|
|
the created tasks contain a status word with interrupts switched on
|
|
so interrupts will automatically get re-enabled when the first task
|
|
starts to run.
|
|
|
|
STEPPING THROUGH HERE USING A DEBUGGER CAN CAUSE BIG PROBLEMS IF THE
|
|
DEBUGGER ALLOWS INTERRUPTS TO BE PROCESSED. */
|
|
portDISABLE_INTERRUPTS();
|
|
|
|
xSchedulerRunning = pdTRUE;
|
|
xTickCount = ( portTickType ) 0;
|
|
|
|
/* Setting up the timer tick is hardware specific and thus in the
|
|
portable interface. */
|
|
if( xPortStartScheduler() )
|
|
{
|
|
/* Should not reach here as if the scheduler is running the
|
|
function will not return. */
|
|
}
|
|
else
|
|
{
|
|
/* Should only reach here if a task calls xTaskEndScheduler(). */
|
|
}
|
|
}
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vTaskEndScheduler( void )
|
|
{
|
|
/* Stop the scheduler interrupts and call the portable scheduler end
|
|
routine so the original ISRs can be restored if necessary. The port
|
|
layer must ensure interrupts enable bit is left in the correct state. */
|
|
portDISABLE_INTERRUPTS();
|
|
xSchedulerRunning = pdFALSE;
|
|
vPortEndScheduler();
|
|
}
|
|
/*----------------------------------------------------------*/
|
|
|
|
void vTaskSuspendAll( void )
|
|
{
|
|
portENTER_CRITICAL();
|
|
++uxSchedulerSuspended;
|
|
portEXIT_CRITICAL();
|
|
}
|
|
/*----------------------------------------------------------*/
|
|
|
|
signed portBASE_TYPE xTaskResumeAll( void )
|
|
{
|
|
register tskTCB *pxTCB;
|
|
signed portBASE_TYPE xAlreadyYielded = pdFALSE;
|
|
|
|
/* It is possible that an ISR caused a task to be removed from an event
|
|
list while the scheduler was suspended. If this was the case then the
|
|
removed task will have been added to the xPendingReadyList. Once the
|
|
scheduler has been resumed it is safe to move all the pending ready
|
|
tasks from this list into their appropriate ready list. */
|
|
portENTER_CRITICAL();
|
|
{
|
|
--uxSchedulerSuspended;
|
|
|
|
if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
|
|
{
|
|
if( uxCurrentNumberOfTasks > ( unsigned portBASE_TYPE ) 0 )
|
|
{
|
|
portBASE_TYPE xYieldRequired = pdFALSE;
|
|
|
|
/* Move any readied tasks from the pending list into the
|
|
appropriate ready list. */
|
|
while( ( pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xPendingReadyList ) ) ) != NULL )
|
|
{
|
|
vListRemove( &( pxTCB->xEventListItem ) );
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
prvAddTaskToReadyQueue( pxTCB );
|
|
|
|
/* If we have moved a task that has a priority higher than
|
|
the current task then we should yield. */
|
|
if( pxTCB->uxPriority >= pxCurrentTCB->uxPriority )
|
|
{
|
|
xYieldRequired = pdTRUE;
|
|
}
|
|
}
|
|
|
|
/* If any ticks occurred while the scheduler was suspended then
|
|
they should be processed now. This ensures the tick count does not
|
|
slip, and that any delayed tasks are resumed at the correct time. */
|
|
if( uxMissedTicks > ( unsigned portBASE_TYPE ) 0 )
|
|
{
|
|
while( uxMissedTicks > ( unsigned portBASE_TYPE ) 0 )
|
|
{
|
|
vTaskIncrementTick();
|
|
--uxMissedTicks;
|
|
}
|
|
|
|
/* As we have processed some ticks it is appropriate to yield
|
|
to ensure the highest priority task that is ready to run is
|
|
the task actually running. */
|
|
#if configUSE_PREEMPTION == 1
|
|
{
|
|
xYieldRequired = pdTRUE;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if( ( xYieldRequired == pdTRUE ) || ( xMissedYield == pdTRUE ) )
|
|
{
|
|
xAlreadyYielded = pdTRUE;
|
|
xMissedYield = pdFALSE;
|
|
taskYIELD();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
portEXIT_CRITICAL();
|
|
|
|
return xAlreadyYielded;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------
|
|
* PUBLIC TASK UTILITIES documented in task.h
|
|
*----------------------------------------------------------*/
|
|
|
|
|
|
|
|
portTickType xTaskGetTickCount( void )
|
|
{
|
|
portTickType xTicks;
|
|
|
|
/* Critical section required if running on a 16 bit processor. */
|
|
taskENTER_CRITICAL();
|
|
{
|
|
xTicks = xTickCount;
|
|
}
|
|
taskEXIT_CRITICAL();
|
|
|
|
return xTicks;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
unsigned portBASE_TYPE uxTaskGetNumberOfTasks( void )
|
|
{
|
|
unsigned portBASE_TYPE uxNumberOfTasks;
|
|
|
|
taskENTER_CRITICAL();
|
|
uxNumberOfTasks = uxCurrentNumberOfTasks;
|
|
taskEXIT_CRITICAL();
|
|
|
|
return uxNumberOfTasks;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( ( configUSE_TRACE_FACILITY == 1 ) && ( INCLUDE_vTaskDelete == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
|
|
|
|
void vTaskList( signed portCHAR *pcWriteBuffer )
|
|
{
|
|
unsigned portBASE_TYPE uxQueue;
|
|
|
|
/* This is a VERY costly function that should be used for debug only.
|
|
It leaves interrupts disabled for a LONG time. */
|
|
|
|
vTaskSuspendAll();
|
|
{
|
|
/* Run through all the lists that could potentially contain a TCB and
|
|
report the task name, state and stack high water mark. */
|
|
|
|
pcWriteBuffer[ 0 ] = ( signed portCHAR ) 0x00;
|
|
strcat( ( portCHAR * ) pcWriteBuffer, ( const portCHAR * ) "\r\n" );
|
|
|
|
uxQueue = uxTopUsedPriority + 1;
|
|
|
|
do
|
|
{
|
|
uxQueue--;
|
|
|
|
if( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxQueue ] ) ) )
|
|
{
|
|
prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &( pxReadyTasksLists[ uxQueue ] ), tskREADY_CHAR );
|
|
}
|
|
}while( uxQueue > ( unsigned portSHORT ) tskIDLE_PRIORITY );
|
|
|
|
if( !listLIST_IS_EMPTY( pxDelayedTaskList ) )
|
|
{
|
|
prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) pxDelayedTaskList, tskBLOCKED_CHAR );
|
|
}
|
|
|
|
if( !listLIST_IS_EMPTY( pxOverflowDelayedTaskList ) )
|
|
{
|
|
prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) pxOverflowDelayedTaskList, tskBLOCKED_CHAR );
|
|
}
|
|
|
|
if( !listLIST_IS_EMPTY( &xTasksWaitingTermination ) )
|
|
{
|
|
prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &xTasksWaitingTermination, tskDELETED_CHAR );
|
|
}
|
|
|
|
if( !listLIST_IS_EMPTY( &xSuspendedTaskList ) )
|
|
{
|
|
prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &xSuspendedTaskList, tskSUSPENDED_CHAR );
|
|
}
|
|
}
|
|
xTaskResumeAll();
|
|
}
|
|
|
|
#endif
|
|
/*----------------------------------------------------------*/
|
|
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
|
|
void vTaskStartTrace( signed portCHAR * pcBuffer, unsigned portLONG ulBufferSize )
|
|
{
|
|
portENTER_CRITICAL();
|
|
{
|
|
pcTraceBuffer = ( volatile signed portCHAR * volatile )pcBuffer;
|
|
pcTraceBufferStart = pcBuffer;
|
|
pcTraceBufferEnd = pcBuffer + ( ulBufferSize - tskSIZE_OF_EACH_TRACE_LINE );
|
|
xTracing = pdTRUE;
|
|
}
|
|
portEXIT_CRITICAL();
|
|
}
|
|
|
|
#endif
|
|
/*----------------------------------------------------------*/
|
|
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
|
|
unsigned portLONG ulTaskEndTrace( void )
|
|
{
|
|
unsigned portLONG ulBufferLength;
|
|
|
|
portENTER_CRITICAL();
|
|
xTracing = pdFALSE;
|
|
portEXIT_CRITICAL();
|
|
|
|
ulBufferLength = ( unsigned portLONG ) ( pcTraceBuffer - pcTraceBufferStart );
|
|
|
|
return ulBufferLength;
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------
|
|
* SCHEDULER INTERNALS AVAILABLE FOR PORTING PURPOSES
|
|
* documented in task.h
|
|
*----------------------------------------------------------*/
|
|
|
|
|
|
inline void vTaskIncrementTick( void )
|
|
{
|
|
/* Called by the portable layer each time a tick interrupt occurs.
|
|
Increments the tick then checks to see if the new tick value will cause any
|
|
tasks to be unblocked. */
|
|
if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
|
|
{
|
|
++xTickCount;
|
|
if( xTickCount == ( portTickType ) 0 )
|
|
{
|
|
xList *pxTemp;
|
|
|
|
/* Tick count has overflowed so we need to swap the delay lists.
|
|
If there are any items in pxDelayedTaskList here then there is
|
|
an error! */
|
|
pxTemp = pxDelayedTaskList;
|
|
pxDelayedTaskList = pxOverflowDelayedTaskList;
|
|
pxOverflowDelayedTaskList = pxTemp;
|
|
xNumOfOverflows++;
|
|
}
|
|
|
|
/* See if this tick has made a timeout expire. */
|
|
prvCheckDelayedTasks();
|
|
}
|
|
else
|
|
{
|
|
++uxMissedTicks;
|
|
|
|
/* The tick hook gets called at regular intervals, even if the
|
|
scheduler is locked. */
|
|
#if ( configUSE_TICK_HOOK == 1 )
|
|
{
|
|
extern void vApplicationTickHook( void );
|
|
|
|
vApplicationTickHook();
|
|
}
|
|
#endif
|
|
}
|
|
|
|
#if ( configUSE_TICK_HOOK == 1 )
|
|
{
|
|
extern void vApplicationTickHook( void );
|
|
|
|
/* Guard against the tick hook being called when the missed tick
|
|
count is being unwound (when the scheduler is being unlocked. */
|
|
if( uxMissedTicks == 0 )
|
|
{
|
|
vApplicationTickHook();
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( ( INCLUDE_vTaskCleanUpResources == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
|
|
|
|
void vTaskCleanUpResources( void )
|
|
{
|
|
unsigned portSHORT usQueue;
|
|
volatile tskTCB *pxTCB;
|
|
|
|
usQueue = ( unsigned portSHORT ) uxTopUsedPriority + ( unsigned portSHORT ) 1;
|
|
|
|
/* Remove any TCB's from the ready queues. */
|
|
do
|
|
{
|
|
usQueue--;
|
|
|
|
while( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ usQueue ] ) ) )
|
|
{
|
|
listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &( pxReadyTasksLists[ usQueue ] ) );
|
|
vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
|
|
|
|
prvDeleteTCB( ( tskTCB * ) pxTCB );
|
|
}
|
|
}while( usQueue > ( unsigned portSHORT ) tskIDLE_PRIORITY );
|
|
|
|
/* Remove any TCB's from the delayed queue. */
|
|
while( !listLIST_IS_EMPTY( &xDelayedTaskList1 ) )
|
|
{
|
|
listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xDelayedTaskList1 );
|
|
vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
|
|
|
|
prvDeleteTCB( ( tskTCB * ) pxTCB );
|
|
}
|
|
|
|
/* Remove any TCB's from the overflow delayed queue. */
|
|
while( !listLIST_IS_EMPTY( &xDelayedTaskList2 ) )
|
|
{
|
|
listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xDelayedTaskList2 );
|
|
vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
|
|
|
|
prvDeleteTCB( ( tskTCB * ) pxTCB );
|
|
}
|
|
|
|
while( !listLIST_IS_EMPTY( &xSuspendedTaskList ) )
|
|
{
|
|
listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xSuspendedTaskList );
|
|
vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
|
|
|
|
prvDeleteTCB( ( tskTCB * ) pxTCB );
|
|
}
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vTaskSwitchContext( void )
|
|
{
|
|
if( uxSchedulerSuspended != ( unsigned portBASE_TYPE ) pdFALSE )
|
|
{
|
|
/* The scheduler is currently suspended - do not allow a context
|
|
switch. */
|
|
xMissedYield = pdTRUE;
|
|
return;
|
|
}
|
|
|
|
/* Find the highest priority queue that contains ready tasks. */
|
|
while( listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxTopReadyPriority ] ) ) )
|
|
{
|
|
--uxTopReadyPriority;
|
|
}
|
|
|
|
/* listGET_OWNER_OF_NEXT_ENTRY walks 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 ] ) );
|
|
vWriteTraceToBuffer();
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vTaskPlaceOnEventList( const xList * const pxEventList, portTickType xTicksToWait )
|
|
{
|
|
portTickType xTimeToWake;
|
|
|
|
/* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
|
|
SCHEDULER SUSPENDED. */
|
|
|
|
/* Place the event list item of the TCB in the appropriate event list.
|
|
This is placed in the list in priority order so the highest priority task
|
|
is the first to be woken by the event. */
|
|
vListInsert( ( xList * ) pxEventList, ( xListItem * ) &( pxCurrentTCB->xEventListItem ) );
|
|
|
|
/* 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. We have
|
|
exclusive access to the ready lists as the scheduler is locked. */
|
|
vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
{
|
|
if( xTicksToWait == portMAX_DELAY )
|
|
{
|
|
/* Add ourselves to the suspended task list instead of a delayed task
|
|
list to ensure we are not woken by a timing event. We will block
|
|
indefinitely. */
|
|
vListInsertEnd( ( xList * ) &xSuspendedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
else
|
|
{
|
|
/* Calculate the time at which the task should be woken if the event does
|
|
not occur. This may overflow but this doesn't matter. */
|
|
xTimeToWake = xTickCount + xTicksToWait;
|
|
|
|
listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
|
|
|
|
if( xTimeToWake < xTickCount )
|
|
{
|
|
/* Wake time has overflowed. Place this item in the overflow list. */
|
|
vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
else
|
|
{
|
|
/* The wake time has not overflowed, so we can use the current block list. */
|
|
vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
}
|
|
}
|
|
#else
|
|
{
|
|
/* Calculate the time at which the task should be woken if the event does
|
|
not occur. This may overflow but this doesn't matter. */
|
|
xTimeToWake = xTickCount + xTicksToWait;
|
|
|
|
listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
|
|
|
|
if( xTimeToWake < xTickCount )
|
|
{
|
|
/* Wake time has overflowed. Place this item in the overflow list. */
|
|
vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
else
|
|
{
|
|
/* The wake time has not overflowed, so we can use the current block list. */
|
|
vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
signed portBASE_TYPE xTaskRemoveFromEventList( const xList * const pxEventList )
|
|
{
|
|
tskTCB *pxUnblockedTCB;
|
|
portBASE_TYPE xReturn;
|
|
|
|
/* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
|
|
SCHEDULER SUSPENDED. It can also be called from within an ISR. */
|
|
|
|
/* The event list is sorted in priority order, so we can remove the
|
|
first in the list, remove the TCB from the delayed list, and add
|
|
it to the ready list.
|
|
|
|
If an event is for a queue that is locked then this function will never
|
|
get called - the lock count on the queue will get modified instead. This
|
|
means we can always expect exclusive access to the event list here. */
|
|
pxUnblockedTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxEventList );
|
|
vListRemove( &( pxUnblockedTCB->xEventListItem ) );
|
|
|
|
if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
|
|
{
|
|
vListRemove( &( pxUnblockedTCB->xGenericListItem ) );
|
|
prvAddTaskToReadyQueue( pxUnblockedTCB );
|
|
}
|
|
else
|
|
{
|
|
/* We cannot access the delayed or ready lists, so will hold this
|
|
task pending until the scheduler is resumed. */
|
|
vListInsertEnd( ( xList * ) &( xPendingReadyList ), &( pxUnblockedTCB->xEventListItem ) );
|
|
}
|
|
|
|
if( pxUnblockedTCB->uxPriority >= pxCurrentTCB->uxPriority )
|
|
{
|
|
/* Return true if the task removed from the event list has
|
|
a higher priority than the calling task. This allows
|
|
the calling task to know if it should force a context
|
|
switch now. */
|
|
xReturn = pdTRUE;
|
|
}
|
|
else
|
|
{
|
|
xReturn = pdFALSE;
|
|
}
|
|
|
|
return xReturn;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vTaskSetTimeOutState( xTimeOutType * const pxTimeOut )
|
|
{
|
|
pxTimeOut->xOverflowCount = xNumOfOverflows;
|
|
pxTimeOut->xTimeOnEntering = xTickCount;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
portBASE_TYPE xTaskCheckForTimeOut( xTimeOutType * const pxTimeOut, portTickType * const pxTicksToWait )
|
|
{
|
|
portBASE_TYPE xReturn;
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
/* If INCLUDE_vTaskSuspend is set to 1 and the block time specified is
|
|
the maximum block time then the task should block indefinitely, and
|
|
therefore never time out. */
|
|
if( *pxTicksToWait == portMAX_DELAY )
|
|
{
|
|
xReturn = pdFALSE;
|
|
}
|
|
else /* We are not blocking indefinitely, perform the checks below. */
|
|
#endif
|
|
|
|
if( ( xNumOfOverflows != pxTimeOut->xOverflowCount ) && ( xTickCount >= pxTimeOut->xTimeOnEntering ) )
|
|
{
|
|
/* The tick count is greater than the time at which vTaskSetTimeout()
|
|
was called, but has also overflowed since vTaskSetTimeOut() was called.
|
|
It must have wrapped all the way around and gone past us again. This
|
|
passed since vTaskSetTimeout() was called. */
|
|
xReturn = pdTRUE;
|
|
}
|
|
else if( ( xTickCount - pxTimeOut->xTimeOnEntering ) < *pxTicksToWait )
|
|
{
|
|
/* Not a genuine timeout. Adjust parameters for time remaining. */
|
|
*pxTicksToWait -= ( xTickCount - pxTimeOut->xTimeOnEntering );
|
|
vTaskSetTimeOutState( pxTimeOut );
|
|
xReturn = pdFALSE;
|
|
}
|
|
else
|
|
{
|
|
xReturn = pdTRUE;
|
|
}
|
|
|
|
return xReturn;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vTaskMissedYield( void )
|
|
{
|
|
xMissedYield = pdTRUE;
|
|
}
|
|
|
|
/*
|
|
* -----------------------------------------------------------
|
|
* The Idle task.
|
|
* ----------------------------------------------------------
|
|
*
|
|
* The portTASK_FUNCTION() macro is used to allow port/compiler specific
|
|
* language extensions. The equivalent prototype for this function is:
|
|
*
|
|
* void prvIdleTask( void *pvParameters );
|
|
*
|
|
*/
|
|
static portTASK_FUNCTION( prvIdleTask, pvParameters )
|
|
{
|
|
/* Stop warnings. */
|
|
( void ) pvParameters;
|
|
|
|
for( ;; )
|
|
{
|
|
/* See if any tasks have been deleted. */
|
|
prvCheckTasksWaitingTermination();
|
|
|
|
#if ( configUSE_PREEMPTION == 0 )
|
|
{
|
|
/* If we are not using preemption we keep forcing a task switch to
|
|
see if any other task has become available. If we are using
|
|
preemption we don't need to do this as any task becoming available
|
|
will automatically get the processor anyway. */
|
|
taskYIELD();
|
|
}
|
|
#endif
|
|
|
|
#if ( ( configUSE_PREEMPTION == 1 ) && ( configIDLE_SHOULD_YIELD == 1 ) )
|
|
{
|
|
/* When using preemption tasks of equal priority will be
|
|
timesliced. If a task that is sharing the idle priority is ready
|
|
to run then the idle task should yield before the end of the
|
|
timeslice.
|
|
|
|
A critical region is not required here as we are just reading from
|
|
the list, and an occasional incorrect value will not matter. If
|
|
the ready list at the idle priority contains more than one task
|
|
then a task other than the idle task is ready to execute. */
|
|
if( listCURRENT_LIST_LENGTH( &( pxReadyTasksLists[ tskIDLE_PRIORITY ] ) ) > ( unsigned portBASE_TYPE ) 1 )
|
|
{
|
|
taskYIELD();
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if ( configUSE_IDLE_HOOK == 1 )
|
|
{
|
|
extern void vApplicationIdleHook( void );
|
|
|
|
/* Call the user defined function from within the idle task. This
|
|
allows the application designer to add background functionality
|
|
without the overhead of a separate task.
|
|
NOTE: vApplicationIdleHook() MUST NOT, UNDER ANY CIRCUMSTANCES,
|
|
CALL A FUNCTION THAT MIGHT BLOCK. */
|
|
vApplicationIdleHook();
|
|
}
|
|
#endif
|
|
}
|
|
} /*lint !e715 pvParameters is not accessed but all task functions require the same prototype. */
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------
|
|
* File private functions documented at the top of the file.
|
|
*----------------------------------------------------------*/
|
|
|
|
|
|
|
|
static void prvInitialiseTCBVariables( tskTCB *pxTCB, const signed portCHAR * const pcName, unsigned portBASE_TYPE uxPriority )
|
|
{
|
|
/* Store the function name in the TCB. */
|
|
strncpy( ( char * ) pxTCB->pcTaskName, ( const char * ) pcName, ( unsigned portSHORT ) configMAX_TASK_NAME_LEN );
|
|
pxTCB->pcTaskName[ ( unsigned portSHORT ) configMAX_TASK_NAME_LEN - ( unsigned portSHORT ) 1 ] = '\0';
|
|
|
|
/* This is used as an array index so must ensure it's not too large. */
|
|
if( uxPriority >= configMAX_PRIORITIES )
|
|
{
|
|
uxPriority = configMAX_PRIORITIES - 1;
|
|
}
|
|
|
|
pxTCB->uxPriority = uxPriority;
|
|
#if ( configUSE_MUTEXES == 1 )
|
|
{
|
|
pxTCB->uxBasePriority = uxPriority;
|
|
}
|
|
#endif
|
|
|
|
vListInitialiseItem( &( pxTCB->xGenericListItem ) );
|
|
vListInitialiseItem( &( pxTCB->xEventListItem ) );
|
|
|
|
/* Set the pxTCB as a link back from the xListItem. This is so we can get
|
|
back to the containing TCB from a generic item in a list. */
|
|
listSET_LIST_ITEM_OWNER( &( pxTCB->xGenericListItem ), pxTCB );
|
|
|
|
/* Event lists are always in priority order. */
|
|
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) uxPriority );
|
|
listSET_LIST_ITEM_OWNER( &( pxTCB->xEventListItem ), pxTCB );
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
static void prvInitialiseTaskLists( void )
|
|
{
|
|
unsigned portBASE_TYPE uxPriority;
|
|
|
|
for( uxPriority = 0; uxPriority < configMAX_PRIORITIES; uxPriority++ )
|
|
{
|
|
vListInitialise( ( xList * ) &( pxReadyTasksLists[ uxPriority ] ) );
|
|
}
|
|
|
|
vListInitialise( ( xList * ) &xDelayedTaskList1 );
|
|
vListInitialise( ( xList * ) &xDelayedTaskList2 );
|
|
vListInitialise( ( xList * ) &xPendingReadyList );
|
|
|
|
#if ( INCLUDE_vTaskDelete == 1 )
|
|
{
|
|
vListInitialise( ( xList * ) &xTasksWaitingTermination );
|
|
}
|
|
#endif
|
|
|
|
#if ( INCLUDE_vTaskSuspend == 1 )
|
|
{
|
|
vListInitialise( ( xList * ) &xSuspendedTaskList );
|
|
}
|
|
#endif
|
|
|
|
/* Start with pxDelayedTaskList using list1 and the pxOverflowDelayedTaskList
|
|
using list2. */
|
|
pxDelayedTaskList = &xDelayedTaskList1;
|
|
pxOverflowDelayedTaskList = &xDelayedTaskList2;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
static void prvCheckTasksWaitingTermination( void )
|
|
{
|
|
#if ( INCLUDE_vTaskDelete == 1 )
|
|
{
|
|
portBASE_TYPE xListIsEmpty;
|
|
|
|
/* ucTasksDeleted is used to prevent vTaskSuspendAll() being called
|
|
too often in the idle task. */
|
|
if( uxTasksDeleted > ( unsigned portBASE_TYPE ) 0 )
|
|
{
|
|
vTaskSuspendAll();
|
|
xListIsEmpty = listLIST_IS_EMPTY( &xTasksWaitingTermination );
|
|
xTaskResumeAll();
|
|
|
|
if( !xListIsEmpty )
|
|
{
|
|
tskTCB *pxTCB;
|
|
|
|
portENTER_CRITICAL();
|
|
{
|
|
pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xTasksWaitingTermination ) );
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
--uxCurrentNumberOfTasks;
|
|
--uxTasksDeleted;
|
|
}
|
|
portEXIT_CRITICAL();
|
|
|
|
prvDeleteTCB( pxTCB );
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
static tskTCB *prvAllocateTCBAndStack( unsigned portSHORT usStackDepth )
|
|
{
|
|
tskTCB *pxNewTCB;
|
|
|
|
/* Allocate space for the TCB. Where the memory comes from depends on
|
|
the implementation of the port malloc function. */
|
|
pxNewTCB = ( tskTCB * ) pvPortMalloc( sizeof( tskTCB ) );
|
|
|
|
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 = ( portSTACK_TYPE * ) pvPortMalloc( ( ( size_t )usStackDepth ) * sizeof( portSTACK_TYPE ) );
|
|
|
|
if( pxNewTCB->pxStack == NULL )
|
|
{
|
|
/* Could not allocate the stack. Delete the allocated TCB. */
|
|
vPortFree( pxNewTCB );
|
|
pxNewTCB = NULL;
|
|
}
|
|
else
|
|
{
|
|
/* Just to help debugging. */
|
|
memset( pxNewTCB->pxStack, tskSTACK_FILL_BYTE, usStackDepth * sizeof( portSTACK_TYPE ) );
|
|
}
|
|
}
|
|
|
|
return pxNewTCB;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
|
|
static void prvListTaskWithinSingleList( const signed portCHAR *pcWriteBuffer, xList *pxList, signed portCHAR cStatus )
|
|
{
|
|
volatile tskTCB *pxNextTCB, *pxFirstTCB;
|
|
static portCHAR pcStatusString[ 50 ];
|
|
unsigned portSHORT usStackRemaining;
|
|
|
|
/* Write the details of all the TCB's in pxList into the buffer. */
|
|
listGET_OWNER_OF_NEXT_ENTRY( pxFirstTCB, pxList );
|
|
do
|
|
{
|
|
listGET_OWNER_OF_NEXT_ENTRY( pxNextTCB, pxList );
|
|
usStackRemaining = usTaskCheckFreeStackSpace( ( unsigned portCHAR * ) pxNextTCB->pxStack );
|
|
sprintf( pcStatusString, ( portCHAR * ) "%s\t\t%c\t%u\t%u\t%u\r\n", pxNextTCB->pcTaskName, cStatus, ( unsigned int ) pxNextTCB->uxPriority, usStackRemaining, ( unsigned int ) pxNextTCB->uxTCBNumber );
|
|
strcat( ( portCHAR * ) pcWriteBuffer, ( portCHAR * ) pcStatusString );
|
|
|
|
} while( pxNextTCB != pxFirstTCB );
|
|
}
|
|
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( configUSE_TRACE_FACILITY == 1 )
|
|
unsigned portSHORT usTaskCheckFreeStackSpace( const unsigned portCHAR * pucStackByte )
|
|
{
|
|
register unsigned portSHORT usCount = 0;
|
|
|
|
while( *pucStackByte == tskSTACK_FILL_BYTE )
|
|
{
|
|
pucStackByte -= portSTACK_GROWTH;
|
|
usCount++;
|
|
}
|
|
|
|
usCount /= sizeof( portSTACK_TYPE );
|
|
|
|
return usCount;
|
|
}
|
|
#endif
|
|
/*-----------------------------------------------------------*/
|
|
|
|
|
|
|
|
#if ( ( INCLUDE_vTaskDelete == 1 ) || ( INCLUDE_vTaskCleanUpResources == 1 ) )
|
|
|
|
static void prvDeleteTCB( tskTCB *pxTCB )
|
|
{
|
|
/* Free up the memory allocated by the scheduler for the task. It is up to
|
|
the task to free any memory allocated at the application level. */
|
|
vPortFree( pxTCB->pxStack );
|
|
vPortFree( pxTCB );
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_xTaskGetCurrentTaskHandle == 1 )
|
|
|
|
xTaskHandle xTaskGetCurrentTaskHandle( void )
|
|
{
|
|
xTaskHandle xReturn;
|
|
|
|
portENTER_CRITICAL();
|
|
{
|
|
xReturn = ( xTaskHandle ) pxCurrentTCB;
|
|
}
|
|
portEXIT_CRITICAL();
|
|
|
|
return xReturn;
|
|
}
|
|
|
|
#endif
|
|
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#if ( INCLUDE_xTaskGetSchedulerState == 1 )
|
|
|
|
portBASE_TYPE xTaskGetSchedulerState( void )
|
|
{
|
|
portBASE_TYPE xReturn;
|
|
|
|
if( xSchedulerRunning == pdFALSE )
|
|
{
|
|
xReturn = taskSCHEDULER_NOT_STARTED;
|
|
}
|
|
else
|
|
{
|
|
if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
|
|
{
|
|
xReturn = taskSCHEDULER_RUNNING;
|
|
}
|
|
else
|
|
{
|
|
xReturn = taskSCHEDULER_SUSPENDED;
|
|
}
|
|
}
|
|
|
|
return xReturn;
|
|
}
|
|
|
|
#endif
|
|
|
|
#if ( configUSE_MUTEXES == 1 )
|
|
|
|
void vTaskPriorityInherit( xTaskHandle * const pxMutexHolder )
|
|
{
|
|
tskTCB * const pxTCB = ( tskTCB * ) pxMutexHolder;
|
|
|
|
if( pxTCB->uxPriority < pxCurrentTCB->uxPriority )
|
|
{
|
|
/* Adjust the mutex holder state to account for its new priority. */
|
|
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) pxCurrentTCB->uxPriority );
|
|
|
|
/* If the task being modified is in the ready state it will need to
|
|
be moved in to a new list. */
|
|
if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ pxTCB->uxPriority ] ), &( pxTCB->xGenericListItem ) ) )
|
|
{
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
|
|
/* Inherit the priority before being moved into the new list. */
|
|
pxTCB->uxPriority = pxCurrentTCB->uxPriority;
|
|
prvAddTaskToReadyQueue( pxTCB );
|
|
}
|
|
else
|
|
{
|
|
/* Just inherit the priority. */
|
|
pxTCB->uxPriority = pxCurrentTCB->uxPriority;
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
#if ( configUSE_MUTEXES == 1 )
|
|
|
|
void vTaskPriorityDisinherit( xTaskHandle * const pxMutexHolder )
|
|
{
|
|
tskTCB * const pxTCB = ( tskTCB * ) pxMutexHolder;
|
|
|
|
if( pxMutexHolder != NULL )
|
|
{
|
|
if( pxTCB->uxPriority != pxTCB->uxBasePriority )
|
|
{
|
|
/* We must be the running task to be able to give the mutex back.
|
|
Remove ourselves from the ready list we currently appear in. */
|
|
vListRemove( &( pxTCB->xGenericListItem ) );
|
|
|
|
/* Disinherit the priority before adding ourselves into the new
|
|
ready list. */
|
|
pxTCB->uxPriority = pxTCB->uxBasePriority;
|
|
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) pxTCB->uxPriority );
|
|
prvAddTaskToReadyQueue( pxTCB );
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
|