2 FreeRTOS.org V4.4.0 - Copyright (C) 2003-2007 Richard Barry.
\r
4 This file is part of the FreeRTOS.org distribution.
\r
6 FreeRTOS.org is free software; you can redistribute it and/or modify
\r
7 it under the terms of the GNU General Public License as published by
\r
8 the Free Software Foundation; either version 2 of the License, or
\r
9 (at your option) any later version.
\r
11 FreeRTOS.org is distributed in the hope that it will be useful,
\r
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
\r
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
\r
14 GNU General Public License for more details.
\r
16 You should have received a copy of the GNU General Public License
\r
17 along with FreeRTOS.org; if not, write to the Free Software
\r
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
\r
20 A special exception to the GPL can be applied should you wish to distribute
\r
21 a combined work that includes FreeRTOS.org, without being obliged to provide
\r
22 the source code for any proprietary components. See the licensing section
\r
23 of http://www.FreeRTOS.org for full details of how and when the exception
\r
26 ***************************************************************************
\r
27 See http://www.FreeRTOS.org for documentation, latest information, license
\r
28 and contact details. Please ensure to read the configuration and relevant
\r
29 port sections of the online documentation.
\r
31 Also see http://www.SafeRTOS.com for an IEC 61508 compliant version, along
\r
32 with development and support options.
\r
33 ***************************************************************************
\r
39 + Call to portRESTORE_CONTEXT has been removed. The first context
\r
40 switch is now performed within sPortStartScheduler().
\r
44 + More use of 8bit data types.
\r
45 + Function name prefixes changed where the data type returned has changed.
\r
46 + configUSE_TRACE_FACILITY is no longer defined by default.
\r
50 + Introduced ucTopReadyPriority. This tracks the highest priority ready
\r
51 queue that contains a valid TCB and thus makes the context switch
\r
54 + prvAddTaskToReadyQueue() has been made a macro.
\r
58 + Added conditional compilation directives.
\r
60 + Rearranged function order.
\r
61 + Creating a task now causes a context switch if the task being created
\r
62 has a higher priority than the calling task - assuming the kernel is
\r
64 + vTaskDelete() now only causes a context switch if the calling task is
\r
65 the task being deleted.
\r
69 + Allow the type of the tick count to be 16 or 32 bits.
\r
70 + Introduce xPendingReadyList feature to allow the time interrupts have to
\r
71 be disabled to be minimised.
\r
72 + Remove the #if( INCLUDE_vTaskSuspendAll ) statements. vTaskSuspendAll()
\r
73 is now always included as it is used by the scheduler itself.
\r
77 + Bug fix - pxCurrentTCB is now initialised before the call to
\r
78 prvInitializeTaskLists(). Previously pxCurrentTCB could be accessed
\r
83 + Change to where lStackSize is declared within sTaskCreate() to prevent
\r
84 compiler warnings with 8051 port.
\r
88 + Explicit use of 'signed' qualifier on portCHAR types added.
\r
89 + Changed odd calculation of initial pxTopOfStack value when
\r
90 portSTACK_GROWTH < 0.
\r
91 + Removed pcVersionNumber definition.
\r
95 + cTaskResumeAll() modified to ensure it can be called prior to the task
\r
96 lists being initialised.
\r
100 + Added API function vTaskDelayUntil().
\r
101 + Added INCLUDE_vTaskDelay conditional compilation.
\r
103 Changes from V2.6.0
\r
105 + Updated the vWriteTraceToBuffer macro to always be 4 byte aligned so it
\r
106 can be used on ARM architectures.
\r
107 + tskMAX_TASK_NAME_LEN definition replaced with the port specific
\r
108 configMAX_TASK_NAME_LEN definition.
\r
109 + Removed the call to strcpy when copying across the task name into the
\r
111 + Added ucTasksDeleted variable to prevent vTaskSuspendAll() being called
\r
112 too often in the idle task.
\r
114 Changes between V3.0.0 and V2.6.1
\r
116 + When resuming the scheduler a yield is performed if either a tick has
\r
117 been missed, or a task is moved from the pending ready list into a ready
\r
118 list. Previously a yield was not performed on this second condition.
\r
119 + Introduced the type portBASE_TYPE. This necessitates several API
\r
121 + Removed the sUsingPreemption variable. The constant defined in
\r
122 portmacro.h is now used directly.
\r
123 + The idle task can now include an optional hook function - and no longer
\r
124 completes its time slice if other tasks with equal priority to it are
\r
126 + See the FreeRTOS.org documentation for more information on V2.x.x to
\r
127 V3.x.x modifications.
\r
129 Changes from V3.1.1
\r
131 + Modified vTaskPrioritySet() and vTaskResume() to allow these functions to
\r
132 be called while the scheduler is suspended.
\r
133 + Corrected the task ordering within event lists.
\r
135 Changes from V3.2.0
\r
137 + Added function xTaskGetCurrentTaskHandle().
\r
139 Changes from V3.2.4
\r
141 + Changed the volatile declarations on some variables to reflect the
\r
142 changes to the list definitions.
\r
143 + Changed the order of the TCB definition so there is commonality between
\r
144 the task control block and a co-routine control block.
\r
145 + Allow the scheduler to be started even if no tasks other than the idle
\r
146 task has been created. This allows co-routines to run even when no tasks
\r
148 + The need for a context switch is now signalled if a task woken by an
\r
149 event has a priority greater or equal to the currently running task.
\r
150 Previously this was only greater than.
\r
152 Changes from V4.0.0
\r
154 + Added the xMissedYield handling.
\r
156 Changes from V4.0.1
\r
158 + The function vTaskList() now suspends the scheduler rather than disabling
\r
159 interrupts during the creation of the task list.
\r
160 + Allow a task to delete itself by passing in its own handle. Previously
\r
161 this could only be done by passing in NULL.
\r
162 + The tick hook function is now called only within a tick isr. Previously
\r
163 it was also called when the tick function was called during the scheduler
\r
166 Changes from V4.0.3
\r
168 + Extra checks have been placed in vTaskPrioritySet() to avoid unnecessary
\r
171 Changed from V4.0.4
\r
173 + Bug fix: The 'value' of the event list item is updated when the priority
\r
174 of a task is changed. Previously only the priority of the TCB itself was
\r
176 + When resuming a task a check is first made to see if the task is actually
\r
178 + vTaskPrioritySet() and vTaskResume() no longer use the event list item.
\r
179 This has not been necessary since V4.0.1 when the xMissedYield handling
\r
181 + Implement xTaskResumeFromISR().
\r
183 Changes from V4.0.5
\r
185 + Added utility functions and xOverflowCount variable to facilitate the
\r
188 Changes from V4.1.2
\r
190 + Tasks that block on events with a timeout of portMAX_DELAY are now
\r
191 blocked indefinitely if configINCLUDE_vTaskSuspend is defined.
\r
192 Previously portMAX_DELAY was just the longest block time possible.
\r
194 Changes from V4.1.3
\r
196 + Very small change made to xTaskCheckForTimeout() as a result of the
\r
197 SafeRTOS testing. This corrects the case where the function can return an
\r
198 invalid value - but only in an extremely unlikely scenario.
\r
200 Changes since V4.3.1:
\r
202 + Added xTaskGetSchedulerState() function.
\r
203 + Added prvIsTaskSuspended() to take into account the Occurrence of
\r
204 vTaskResume() or vTaskResumeFromISR() being called passing in the
\r
205 handle of a task that appears in the Suspended list only because it
\r
206 is blocked on an event without a timeout being specified.
\r
207 + Updated xTaskCheckForTimeout() to take into account that tasks blocked
\r
208 using the Suspended list should never time out.
\r
212 #include <stdlib.h>
\r
213 #include <string.h>
\r
215 #include "FreeRTOS.h"
\r
219 * Macro to define the amount of stack available to the idle task.
\r
221 #define tskIDLE_STACK_SIZE configMINIMAL_STACK_SIZE
\r
225 * Default a definitions for backwards compatibility with old
\r
226 * portmacro.h files.
\r
228 #ifndef configMAX_TASK_NAME_LEN
\r
229 #define configMAX_TASK_NAME_LEN 16
\r
232 #ifndef configIDLE_SHOULD_YIELD
\r
233 #define configIDLE_SHOULD_YIELD 1
\r
236 #if configMAX_TASK_NAME_LEN < 1
\r
237 #undef configMAX_TASK_NAME_LEN
\r
238 #define configMAX_TASK_NAME_LEN 1
\r
241 #ifndef INCLUDE_xTaskResumeFromISR
\r
242 #define INCLUDE_xTaskResumeFromISR 1
\r
245 #ifndef INCLUDE_xTaskGetSchedulerState
\r
246 #define INCLUDE_xTaskGetSchedulerState 0
\r
250 * Task control block. A task control block (TCB) is allocated to each task,
\r
251 * and stores the context of the task.
\r
253 typedef struct tskTaskControlBlock
\r
255 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. */
\r
256 xListItem xGenericListItem; /*< List item used to place the TCB in ready and blocked queues. */
\r
257 xListItem xEventListItem; /*< List item used to place the TCB in event lists. */
\r
258 unsigned portBASE_TYPE uxPriority; /*< The priority of the task where 0 is the lowest priority. */
\r
259 portSTACK_TYPE *pxStack; /*< Points to the start of the stack. */
\r
260 signed portCHAR pcTaskName[ configMAX_TASK_NAME_LEN ];/*< Descriptive name given to the task when created. Facilitates debugging only. */
\r
262 #if ( configUSE_TRACE_FACILITY == 1 )
\r
263 unsigned portBASE_TYPE uxTCBNumber; /*< This is used for tracing the scheduler and making debugging easier only. */
\r
266 #if ( configUSE_MUTEXES == 1 )
\r
267 unsigned portBASE_TYPE uxBasePriority;
\r
274 tskTCB * volatile pxCurrentTCB = NULL;
\r
276 /* Lists for ready and blocked tasks. --------------------*/
\r
278 static xList pxReadyTasksLists[ configMAX_PRIORITIES ]; /*< Prioritised ready tasks. */
\r
279 static xList xDelayedTaskList1; /*< Delayed tasks. */
\r
280 static xList xDelayedTaskList2; /*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */
\r
281 static xList * volatile pxDelayedTaskList; /*< Points to the delayed task list currently being used. */
\r
282 static xList * volatile pxOverflowDelayedTaskList; /*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */
\r
283 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. */
\r
285 #if ( INCLUDE_vTaskDelete == 1 )
\r
287 static volatile xList xTasksWaitingTermination; /*< Tasks that have been deleted - but the their memory not yet freed. */
\r
288 static volatile unsigned portBASE_TYPE uxTasksDeleted = ( unsigned portBASE_TYPE ) 0;
\r
292 #if ( INCLUDE_vTaskSuspend == 1 )
\r
294 static xList xSuspendedTaskList; /*< Tasks that are currently suspended. */
\r
298 /* File private variables. --------------------------------*/
\r
299 static volatile unsigned portBASE_TYPE uxCurrentNumberOfTasks = ( unsigned portBASE_TYPE ) 0;
\r
300 static volatile portTickType xTickCount = ( portTickType ) 0;
\r
301 static unsigned portBASE_TYPE uxTopUsedPriority = tskIDLE_PRIORITY;
\r
302 static volatile unsigned portBASE_TYPE uxTopReadyPriority = tskIDLE_PRIORITY;
\r
303 static volatile signed portBASE_TYPE xSchedulerRunning = pdFALSE;
\r
304 static volatile unsigned portBASE_TYPE uxSchedulerSuspended = ( unsigned portBASE_TYPE ) pdFALSE;
\r
305 static volatile unsigned portBASE_TYPE uxMissedTicks = ( unsigned portBASE_TYPE ) 0;
\r
306 static volatile portBASE_TYPE xMissedYield = ( portBASE_TYPE ) pdFALSE;
\r
307 static volatile portBASE_TYPE xNumOfOverflows = ( portBASE_TYPE ) 0;
\r
308 /* Debugging and trace facilities private variables and macros. ------------*/
\r
311 * The value used to fill the stack of a task when the task is created. This
\r
312 * is used purely for checking the high water mark for tasks.
\r
314 #define tskSTACK_FILL_BYTE ( 0xa5 )
\r
317 * Macros used by vListTask to indicate which state a task is in.
\r
319 #define tskBLOCKED_CHAR ( ( signed portCHAR ) 'B' )
\r
320 #define tskREADY_CHAR ( ( signed portCHAR ) 'R' )
\r
321 #define tskDELETED_CHAR ( ( signed portCHAR ) 'D' )
\r
322 #define tskSUSPENDED_CHAR ( ( signed portCHAR ) 'S' )
\r
325 * Macros and private variables used by the trace facility.
\r
327 #if ( configUSE_TRACE_FACILITY == 1 )
\r
329 #define tskSIZE_OF_EACH_TRACE_LINE ( ( unsigned portLONG ) ( sizeof( unsigned portLONG ) + sizeof( unsigned portLONG ) ) )
\r
330 static volatile signed portCHAR * volatile pcTraceBuffer;
\r
331 static signed portCHAR *pcTraceBufferStart;
\r
332 static signed portCHAR *pcTraceBufferEnd;
\r
333 static signed portBASE_TYPE xTracing = pdFALSE;
\r
338 * Macro that writes a trace of scheduler activity to a buffer. This trace
\r
339 * shows which task is running when and is very useful as a debugging tool.
\r
340 * As this macro is called each context switch it is a good idea to undefine
\r
341 * it if not using the facility.
\r
343 #if ( configUSE_TRACE_FACILITY == 1 )
\r
345 #define vWriteTraceToBuffer() \
\r
349 static unsigned portBASE_TYPE uxPreviousTask = 255; \
\r
351 if( uxPreviousTask != pxCurrentTCB->uxTCBNumber ) \
\r
353 if( ( pcTraceBuffer + tskSIZE_OF_EACH_TRACE_LINE ) < pcTraceBufferEnd ) \
\r
355 uxPreviousTask = pxCurrentTCB->uxTCBNumber; \
\r
356 *( unsigned portLONG * ) pcTraceBuffer = ( unsigned portLONG ) xTickCount; \
\r
357 pcTraceBuffer += sizeof( unsigned portLONG ); \
\r
358 *( unsigned portLONG * ) pcTraceBuffer = ( unsigned portLONG ) uxPreviousTask; \
\r
359 pcTraceBuffer += sizeof( unsigned portLONG ); \
\r
363 xTracing = pdFALSE; \
\r
371 #define vWriteTraceToBuffer()
\r
377 * Place the task represented by pxTCB into the appropriate ready queue for
\r
378 * the task. It is inserted at the end of the list. One quirk of this is
\r
379 * that if the task being inserted is at the same priority as the currently
\r
380 * executing task, then it will only be rescheduled after the currently
\r
381 * executing task has been rescheduled.
\r
383 #define prvAddTaskToReadyQueue( pxTCB ) \
\r
385 if( pxTCB->uxPriority > uxTopReadyPriority ) \
\r
387 uxTopReadyPriority = pxTCB->uxPriority; \
\r
389 vListInsertEnd( ( xList * ) &( pxReadyTasksLists[ pxTCB->uxPriority ] ), &( pxTCB->xGenericListItem ) ); \
\r
393 * Macro that looks at the list of tasks that are currently delayed to see if
\r
394 * any require waking.
\r
396 * Tasks are stored in the queue in the order of their wake time - meaning
\r
397 * once one tasks has been found whose timer has not expired we need not look
\r
398 * any further down the list.
\r
400 #define prvCheckDelayedTasks() \
\r
402 register tskTCB *pxTCB; \
\r
404 while( ( pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxDelayedTaskList ) ) != NULL ) \
\r
406 if( xTickCount < listGET_LIST_ITEM_VALUE( &( pxTCB->xGenericListItem ) ) ) \
\r
410 vListRemove( &( pxTCB->xGenericListItem ) ); \
\r
411 /* Is the task waiting on an event also? */ \
\r
412 if( pxTCB->xEventListItem.pvContainer ) \
\r
414 vListRemove( &( pxTCB->xEventListItem ) ); \
\r
416 prvAddTaskToReadyQueue( pxTCB ); \
\r
421 * Several functions take an xTaskHandle parameter that can optionally be NULL,
\r
422 * where NULL is used to indicate that the handle of the currently executing
\r
423 * task should be used in place of the parameter. This macro simply checks to
\r
424 * see if the parameter is NULL and returns a pointer to the appropriate TCB.
\r
426 #define prvGetTCBFromHandle( pxHandle ) ( ( pxHandle == NULL ) ? ( tskTCB * ) pxCurrentTCB : ( tskTCB * ) pxHandle )
\r
429 /* File private functions. --------------------------------*/
\r
432 * Utility to ready a TCB for a given task. Mainly just copies the parameters
\r
433 * into the TCB structure.
\r
435 static void prvInitialiseTCBVariables( tskTCB *pxTCB, const signed portCHAR * const pcName, unsigned portBASE_TYPE uxPriority );
\r
438 * Utility to ready all the lists used by the scheduler. This is called
\r
439 * automatically upon the creation of the first task.
\r
441 static void prvInitialiseTaskLists( void );
\r
444 * The idle task, which as all tasks is implemented as a never ending loop.
\r
445 * The idle task is automatically created and added to the ready lists upon
\r
446 * creation of the first user task.
\r
448 * The portTASK_FUNCTION_PROTO() macro is used to allow port/compiler specific
\r
449 * language extensions. The equivalent prototype for this function is:
\r
451 * void prvIdleTask( void *pvParameters );
\r
454 static portTASK_FUNCTION_PROTO( prvIdleTask, pvParameters );
\r
457 * Utility to free all memory allocated by the scheduler to hold a TCB,
\r
458 * including the stack pointed to by the TCB.
\r
460 * This does not free memory allocated by the task itself (i.e. memory
\r
461 * allocated by calls to pvPortMalloc from within the tasks application code).
\r
463 #if ( ( INCLUDE_vTaskDelete == 1 ) || ( INCLUDE_vTaskCleanUpResources == 1 ) )
\r
464 static void prvDeleteTCB( tskTCB *pxTCB );
\r
468 * Used only by the idle task. This checks to see if anything has been placed
\r
469 * in the list of tasks waiting to be deleted. If so the task is cleaned up
\r
470 * and its TCB deleted.
\r
472 static void prvCheckTasksWaitingTermination( void );
\r
475 * Allocates memory from the heap for a TCB and associated stack. Checks the
\r
476 * allocation was successful.
\r
478 static tskTCB *prvAllocateTCBAndStack( unsigned portSHORT usStackDepth );
\r
481 * Called from vTaskList. vListTasks details all the tasks currently under
\r
482 * control of the scheduler. The tasks may be in one of a number of lists.
\r
483 * prvListTaskWithinSingleList accepts a list and details the tasks from
\r
484 * within just that list.
\r
486 * THIS FUNCTION IS INTENDED FOR DEBUGGING ONLY, AND SHOULD NOT BE CALLED FROM
\r
487 * NORMAL APPLICATION CODE.
\r
489 #if ( configUSE_TRACE_FACILITY == 1 )
\r
491 static void prvListTaskWithinSingleList( const signed portCHAR *pcWriteBuffer, xList *pxList, signed portCHAR cStatus );
\r
496 * When a task is created, the stack of the task is filled with a known value.
\r
497 * This function determines the 'high water mark' of the task stack by
\r
498 * determining how much of the stack remains at the original preset value.
\r
500 #if ( configUSE_TRACE_FACILITY == 1 )
\r
502 unsigned portSHORT usTaskCheckFreeStackSpace( const unsigned portCHAR * pucStackByte );
\r
507 * Checks that a task being resumed (unsuspended) is actually in the Suspended
\r
510 #if ( INCLUDE_vTaskSuspend == 1 )
\r
512 static portBASE_TYPE prvIsTaskSuspended( const tskTCB * const pxTCB );
\r
522 /*-----------------------------------------------------------
\r
523 * TASK CREATION API documented in task.h
\r
524 *----------------------------------------------------------*/
\r
526 signed portBASE_TYPE xTaskCreate( pdTASK_CODE pvTaskCode, const signed portCHAR * const pcName, unsigned portSHORT usStackDepth, void *pvParameters, unsigned portBASE_TYPE uxPriority, xTaskHandle *pxCreatedTask )
\r
528 signed portBASE_TYPE xReturn;
\r
530 #if ( configUSE_TRACE_FACILITY == 1 )
\r
531 static unsigned portBASE_TYPE uxTaskNumber = 0; /*lint !e956 Static is deliberate - this is guarded before use. */
\r
534 /* Allocate the memory required by the TCB and stack for the new task.
\r
535 checking that the allocation was successful. */
\r
536 pxNewTCB = prvAllocateTCBAndStack( usStackDepth );
\r
538 if( pxNewTCB != NULL )
\r
540 portSTACK_TYPE *pxTopOfStack;
\r
542 /* Setup the newly allocated TCB with the initial state of the task. */
\r
543 prvInitialiseTCBVariables( pxNewTCB, pcName, uxPriority );
\r
545 /* Calculate the top of stack address. This depends on whether the
\r
546 stack grows from high memory to low (as per the 80x86) or visa versa.
\r
547 portSTACK_GROWTH is used to make the result positive or negative as
\r
548 required by the port. */
\r
549 #if portSTACK_GROWTH < 0
\r
551 pxTopOfStack = pxNewTCB->pxStack + ( usStackDepth - 1 );
\r
555 pxTopOfStack = pxNewTCB->pxStack;
\r
559 /* Initialize the TCB stack to look as if the task was already running,
\r
560 but had been interrupted by the scheduler. The return address is set
\r
561 to the start of the task function. Once the stack has been initialised
\r
562 the top of stack variable is updated. */
\r
563 pxNewTCB->pxTopOfStack = pxPortInitialiseStack( pxTopOfStack, pvTaskCode, pvParameters );
\r
565 /* We are going to manipulate the task queues to add this task to a
\r
566 ready list, so must make sure no interrupts occur. */
\r
567 portENTER_CRITICAL();
\r
569 uxCurrentNumberOfTasks++;
\r
570 if( uxCurrentNumberOfTasks == ( unsigned portBASE_TYPE ) 1 )
\r
572 /* As this is the first task it must also be the current task. */
\r
573 pxCurrentTCB = pxNewTCB;
\r
575 /* This is the first task to be created so do the preliminary
\r
576 initialisation required. We will not recover if this call
\r
577 fails, but we will report the failure. */
\r
578 prvInitialiseTaskLists();
\r
582 /* If the scheduler is not already running, make this task the
\r
583 current task if it is the highest priority task to be created
\r
585 if( xSchedulerRunning == pdFALSE )
\r
587 if( pxCurrentTCB->uxPriority <= uxPriority )
\r
589 pxCurrentTCB = pxNewTCB;
\r
594 /* Remember the top priority to make context switching faster. Use
\r
595 the priority in pxNewTCB as this has been capped to a valid value. */
\r
596 if( pxNewTCB->uxPriority > uxTopUsedPriority )
\r
598 uxTopUsedPriority = pxNewTCB->uxPriority;
\r
601 #if ( configUSE_TRACE_FACILITY == 1 )
\r
603 /* Add a counter into the TCB for tracing only. */
\r
604 pxNewTCB->uxTCBNumber = uxTaskNumber;
\r
609 prvAddTaskToReadyQueue( pxNewTCB );
\r
613 portEXIT_CRITICAL();
\r
617 xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY;
\r
620 if( xReturn == pdPASS )
\r
622 if( ( void * ) pxCreatedTask != NULL )
\r
624 /* Pass the TCB out - in an anonymous way. The calling function/
\r
625 task can use this as a handle to delete the task later if
\r
627 *pxCreatedTask = ( xTaskHandle ) pxNewTCB;
\r
630 if( xSchedulerRunning != pdFALSE )
\r
632 /* If the created task is of a higher priority than the current task
\r
633 then it should run now. */
\r
634 if( pxCurrentTCB->uxPriority < uxPriority )
\r
643 /*-----------------------------------------------------------*/
\r
645 #if ( INCLUDE_vTaskDelete == 1 )
\r
647 void vTaskDelete( xTaskHandle pxTaskToDelete )
\r
651 taskENTER_CRITICAL();
\r
653 /* Ensure a yield is performed if the current task is being
\r
655 if( pxTaskToDelete == pxCurrentTCB )
\r
657 pxTaskToDelete = NULL;
\r
660 /* If null is passed in here then we are deleting ourselves. */
\r
661 pxTCB = prvGetTCBFromHandle( pxTaskToDelete );
\r
663 /* Remove task from the ready list and place in the termination list.
\r
664 This will stop the task from be scheduled. The idle task will check
\r
665 the termination list and free up any memory allocated by the
\r
666 scheduler for the TCB and stack. */
\r
667 vListRemove( &( pxTCB->xGenericListItem ) );
\r
669 /* Is the task waiting on an event also? */
\r
670 if( pxTCB->xEventListItem.pvContainer )
\r
672 vListRemove( &( pxTCB->xEventListItem ) );
\r
675 vListInsertEnd( ( xList * ) &xTasksWaitingTermination, &( pxTCB->xGenericListItem ) );
\r
677 /* Increment the ucTasksDeleted variable so the idle task knows
\r
678 there is a task that has been deleted and that it should therefore
\r
679 check the xTasksWaitingTermination list. */
\r
682 taskEXIT_CRITICAL();
\r
684 /* Force a reschedule if we have just deleted the current task. */
\r
685 if( xSchedulerRunning != pdFALSE )
\r
687 if( ( void * ) pxTaskToDelete == NULL )
\r
701 /*-----------------------------------------------------------
\r
702 * TASK CONTROL API documented in task.h
\r
703 *----------------------------------------------------------*/
\r
705 #if ( INCLUDE_vTaskDelayUntil == 1 )
\r
707 void vTaskDelayUntil( portTickType * const pxPreviousWakeTime, portTickType xTimeIncrement )
\r
709 portTickType xTimeToWake;
\r
710 portBASE_TYPE xAlreadyYielded, xShouldDelay = pdFALSE;
\r
714 /* Generate the tick time at which the task wants to wake. */
\r
715 xTimeToWake = *pxPreviousWakeTime + xTimeIncrement;
\r
717 if( xTickCount < *pxPreviousWakeTime )
\r
719 /* The tick count has overflowed since this function was
\r
720 lasted called. In this case the only time we should ever
\r
721 actually delay is if the wake time has also overflowed,
\r
722 and the wake time is greater than the tick time. When this
\r
723 is the case it is as if neither time had overflowed. */
\r
724 if( ( xTimeToWake < *pxPreviousWakeTime ) && ( xTimeToWake > xTickCount ) )
\r
726 xShouldDelay = pdTRUE;
\r
731 /* The tick time has not overflowed. In this case we will
\r
732 delay if either the wake time has overflowed, and/or the
\r
733 tick time is less than the wake time. */
\r
734 if( ( xTimeToWake < *pxPreviousWakeTime ) || ( xTimeToWake > xTickCount ) )
\r
736 xShouldDelay = pdTRUE;
\r
740 /* Update the wake time ready for the next call. */
\r
741 *pxPreviousWakeTime = xTimeToWake;
\r
745 /* We must remove ourselves from the ready list before adding
\r
746 ourselves to the blocked list as the same list item is used for
\r
748 vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
750 /* The list item will be inserted in wake time order. */
\r
751 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
\r
753 if( xTimeToWake < xTickCount )
\r
755 /* Wake time has overflowed. Place this item in the
\r
757 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
761 /* The wake time has not overflowed, so we can use the
\r
762 current block list. */
\r
763 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
767 xAlreadyYielded = xTaskResumeAll();
\r
769 /* Force a reschedule if xTaskResumeAll has not already done so, we may
\r
770 have put ourselves to sleep. */
\r
771 if( !xAlreadyYielded )
\r
778 /*-----------------------------------------------------------*/
\r
780 #if ( INCLUDE_vTaskDelay == 1 )
\r
782 void vTaskDelay( portTickType xTicksToDelay )
\r
784 portTickType xTimeToWake;
\r
785 signed portBASE_TYPE xAlreadyYielded = pdFALSE;
\r
787 /* A delay time of zero just forces a reschedule. */
\r
788 if( xTicksToDelay > ( portTickType ) 0 )
\r
792 /* A task that is removed from the event list while the
\r
793 scheduler is suspended will not get placed in the ready
\r
794 list or removed from the blocked list until the scheduler
\r
797 This task cannot be in an event list as it is the currently
\r
800 /* Calculate the time to wake - this may overflow but this is
\r
802 xTimeToWake = xTickCount + xTicksToDelay;
\r
804 /* We must remove ourselves from the ready list before adding
\r
805 ourselves to the blocked list as the same list item is used for
\r
807 vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
809 /* The list item will be inserted in wake time order. */
\r
810 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
\r
812 if( xTimeToWake < xTickCount )
\r
814 /* Wake time has overflowed. Place this item in the
\r
816 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
820 /* The wake time has not overflowed, so we can use the
\r
821 current block list. */
\r
822 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
825 xAlreadyYielded = xTaskResumeAll();
\r
828 /* Force a reschedule if xTaskResumeAll has not already done so, we may
\r
829 have put ourselves to sleep. */
\r
830 if( !xAlreadyYielded )
\r
837 /*-----------------------------------------------------------*/
\r
839 #if ( INCLUDE_uxTaskPriorityGet == 1 )
\r
841 unsigned portBASE_TYPE uxTaskPriorityGet( xTaskHandle pxTask )
\r
844 unsigned portBASE_TYPE uxReturn;
\r
846 taskENTER_CRITICAL();
\r
848 /* If null is passed in here then we are changing the
\r
849 priority of the calling function. */
\r
850 pxTCB = prvGetTCBFromHandle( pxTask );
\r
851 uxReturn = pxTCB->uxPriority;
\r
853 taskEXIT_CRITICAL();
\r
859 /*-----------------------------------------------------------*/
\r
861 #if ( INCLUDE_vTaskPrioritySet == 1 )
\r
863 void vTaskPrioritySet( xTaskHandle pxTask, unsigned portBASE_TYPE uxNewPriority )
\r
866 unsigned portBASE_TYPE uxCurrentPriority, xYieldRequired = pdFALSE;
\r
868 /* Ensure the new priority is valid. */
\r
869 if( uxNewPriority >= configMAX_PRIORITIES )
\r
871 uxNewPriority = configMAX_PRIORITIES - 1;
\r
874 taskENTER_CRITICAL();
\r
876 /* If null is passed in here then we are changing the
\r
877 priority of the calling function. */
\r
878 pxTCB = prvGetTCBFromHandle( pxTask );
\r
880 #if ( configUSE_MUTEXES == 1 )
\r
882 uxCurrentPriority = pxTCB->uxBasePriority;
\r
886 uxCurrentPriority = pxTCB->uxPriority;
\r
890 if( uxCurrentPriority != uxNewPriority )
\r
892 /* The priority change may have readied a task of higher
\r
893 priority than the calling task. */
\r
894 if( uxNewPriority > uxCurrentPriority )
\r
896 if( pxTask != NULL )
\r
898 /* The priority of another task is being raised. If we
\r
899 were raising the priority of the currently running task
\r
900 there would be no need to switch as it must have already
\r
901 been the highest priority task. */
\r
902 xYieldRequired = pdTRUE;
\r
905 else if( pxTask == NULL )
\r
907 /* Setting our own priority down means there may now be another
\r
908 task of higher priority that is ready to execute. */
\r
909 xYieldRequired = pdTRUE;
\r
914 #if ( configUSE_MUTEXES == 1 )
\r
916 /* Only change the priority being used if the task is not
\r
917 currently using an inherited priority. */
\r
918 if( pxTCB->uxBasePriority == pxTCB->uxPriority )
\r
920 pxTCB->uxPriority = uxNewPriority;
\r
923 /* The base priority gets set whatever. */
\r
924 pxTCB->uxBasePriority = uxNewPriority;
\r
928 pxTCB->uxPriority = uxNewPriority;
\r
932 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) uxNewPriority );
\r
934 /* If the task is in the blocked or suspended list we need do
\r
935 nothing more than change it's priority variable. However, if
\r
936 the task is in a ready list it needs to be removed and placed
\r
937 in the queue appropriate to its new priority. */
\r
938 if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ uxCurrentPriority ] ), &( pxTCB->xGenericListItem ) ) )
\r
940 /* The task is currently in its ready list - remove before adding
\r
941 it to it's new ready list. As we are in a critical section we
\r
942 can do this even if the scheduler is suspended. */
\r
943 vListRemove( &( pxTCB->xGenericListItem ) );
\r
944 prvAddTaskToReadyQueue( pxTCB );
\r
947 if( xYieldRequired == pdTRUE )
\r
953 taskEXIT_CRITICAL();
\r
957 /*-----------------------------------------------------------*/
\r
959 #if ( INCLUDE_vTaskSuspend == 1 )
\r
961 void vTaskSuspend( xTaskHandle pxTaskToSuspend )
\r
965 taskENTER_CRITICAL();
\r
967 /* Ensure a yield is performed if the current task is being
\r
969 if( pxTaskToSuspend == pxCurrentTCB )
\r
971 pxTaskToSuspend = NULL;
\r
974 /* If null is passed in here then we are suspending ourselves. */
\r
975 pxTCB = prvGetTCBFromHandle( pxTaskToSuspend );
\r
977 /* Remove task from the ready/delayed list and place in the suspended list. */
\r
978 vListRemove( &( pxTCB->xGenericListItem ) );
\r
980 /* Is the task waiting on an event also? */
\r
981 if( pxTCB->xEventListItem.pvContainer )
\r
983 vListRemove( &( pxTCB->xEventListItem ) );
\r
986 vListInsertEnd( ( xList * ) &xSuspendedTaskList, &( pxTCB->xGenericListItem ) );
\r
988 taskEXIT_CRITICAL();
\r
990 /* We may have just suspended the current task. */
\r
991 if( ( void * ) pxTaskToSuspend == NULL )
\r
998 /*-----------------------------------------------------------*/
\r
1000 #if ( INCLUDE_vTaskSuspend == 1 )
\r
1002 static portBASE_TYPE prvIsTaskSuspended( const tskTCB * const pxTCB )
\r
1004 portBASE_TYPE xReturn = pdFALSE;
\r
1006 /* Is the task we are attempting to resume actually in the
\r
1007 suspended list? */
\r
1008 if( listIS_CONTAINED_WITHIN( &xSuspendedTaskList, &( pxTCB->xGenericListItem ) ) != pdFALSE )
\r
1010 /* Has the task already been resumed from within an ISR? */
\r
1011 if( listIS_CONTAINED_WITHIN( &xPendingReadyList, &( pxTCB->xEventListItem ) ) != pdTRUE )
\r
1013 /* Is it in the suspended list because it is in the
\r
1014 Suspended state? It is possible to be in the suspended
\r
1015 list because it is blocked on a task with no timeout
\r
1017 if( listIS_CONTAINED_WITHIN( NULL, &( pxTCB->xEventListItem ) ) == pdTRUE )
\r
1028 /*-----------------------------------------------------------*/
\r
1030 #if ( INCLUDE_vTaskSuspend == 1 )
\r
1032 void vTaskResume( xTaskHandle pxTaskToResume )
\r
1036 /* Remove the task from whichever list it is currently in, and place
\r
1037 it in the ready list. */
\r
1038 pxTCB = ( tskTCB * ) pxTaskToResume;
\r
1040 /* The parameter cannot be NULL as it is impossible to resume the
\r
1041 currently executing task. */
\r
1042 if( pxTCB != NULL )
\r
1044 taskENTER_CRITICAL();
\r
1046 if( prvIsTaskSuspended( pxTCB ) == pdTRUE )
\r
1048 /* As we are in a critical section we can access the ready
\r
1049 lists even if the scheduler is suspended. */
\r
1050 vListRemove( &( pxTCB->xGenericListItem ) );
\r
1051 prvAddTaskToReadyQueue( pxTCB );
\r
1053 /* We may have just resumed a higher priority task. */
\r
1054 if( pxTCB->uxPriority >= pxCurrentTCB->uxPriority )
\r
1056 /* This yield may not cause the task just resumed to run, but
\r
1057 will leave the lists in the correct state for the next yield. */
\r
1062 taskEXIT_CRITICAL();
\r
1068 /*-----------------------------------------------------------*/
\r
1070 #if ( ( INCLUDE_xTaskResumeFromISR == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
\r
1072 portBASE_TYPE xTaskResumeFromISR( xTaskHandle pxTaskToResume )
\r
1074 portBASE_TYPE xYieldRequired = pdFALSE;
\r
1077 pxTCB = ( tskTCB * ) pxTaskToResume;
\r
1079 if( prvIsTaskSuspended( pxTCB ) == pdTRUE )
\r
1081 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
\r
1083 xYieldRequired = ( pxTCB->uxPriority >= pxCurrentTCB->uxPriority );
\r
1084 vListRemove( &( pxTCB->xGenericListItem ) );
\r
1085 prvAddTaskToReadyQueue( pxTCB );
\r
1089 /* We cannot access the delayed or ready lists, so will hold this
\r
1090 task pending until the scheduler is resumed, at which point a
\r
1091 yield will be performed if necessary. */
\r
1092 vListInsertEnd( ( xList * ) &( xPendingReadyList ), &( pxTCB->xEventListItem ) );
\r
1096 return xYieldRequired;
\r
1104 /*-----------------------------------------------------------
\r
1105 * PUBLIC SCHEDULER CONTROL documented in task.h
\r
1106 *----------------------------------------------------------*/
\r
1109 void vTaskStartScheduler( void )
\r
1111 portBASE_TYPE xReturn;
\r
1113 /* Add the idle task at the lowest priority. */
\r
1114 xReturn = xTaskCreate( prvIdleTask, ( signed portCHAR * ) "IDLE", tskIDLE_STACK_SIZE, ( void * ) NULL, tskIDLE_PRIORITY, ( xTaskHandle * ) NULL );
\r
1116 if( xReturn == pdPASS )
\r
1118 /* Interrupts are turned off here, to ensure a tick does not occur
\r
1119 before or during the call to xPortStartScheduler(). The stacks of
\r
1120 the created tasks contain a status word with interrupts switched on
\r
1121 so interrupts will automatically get re-enabled when the first task
\r
1124 STEPPING THROUGH HERE USING A DEBUGGER CAN CAUSE BIG PROBLEMS IF THE
\r
1125 DEBUGGER ALLOWS INTERRUPTS TO BE PROCESSED. */
\r
1126 portDISABLE_INTERRUPTS();
\r
1128 xSchedulerRunning = pdTRUE;
\r
1129 xTickCount = ( portTickType ) 0;
\r
1131 /* Setting up the timer tick is hardware specific and thus in the
\r
1132 portable interface. */
\r
1133 if( xPortStartScheduler() )
\r
1135 /* Should not reach here as if the scheduler is running the
\r
1136 function will not return. */
\r
1140 /* Should only reach here if a task calls xTaskEndScheduler(). */
\r
1144 /*-----------------------------------------------------------*/
\r
1146 void vTaskEndScheduler( void )
\r
1148 /* Stop the scheduler interrupts and call the portable scheduler end
\r
1149 routine so the original ISRs can be restored if necessary. The port
\r
1150 layer must ensure interrupts enable bit is left in the correct state. */
\r
1151 portDISABLE_INTERRUPTS();
\r
1152 xSchedulerRunning = pdFALSE;
\r
1153 vPortEndScheduler();
\r
1155 /*----------------------------------------------------------*/
\r
1157 void vTaskSuspendAll( void )
\r
1159 portENTER_CRITICAL();
\r
1160 ++uxSchedulerSuspended;
\r
1161 portEXIT_CRITICAL();
\r
1163 /*----------------------------------------------------------*/
\r
1165 signed portBASE_TYPE xTaskResumeAll( void )
\r
1167 register tskTCB *pxTCB;
\r
1168 signed portBASE_TYPE xAlreadyYielded = pdFALSE;
\r
1170 /* It is possible that an ISR caused a task to be removed from an event
\r
1171 list while the scheduler was suspended. If this was the case then the
\r
1172 removed task will have been added to the xPendingReadyList. Once the
\r
1173 scheduler has been resumed it is safe to move all the pending ready
\r
1174 tasks from this list into their appropriate ready list. */
\r
1175 portENTER_CRITICAL();
\r
1177 --uxSchedulerSuspended;
\r
1179 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
\r
1181 if( uxCurrentNumberOfTasks > ( unsigned portBASE_TYPE ) 0 )
\r
1183 portBASE_TYPE xYieldRequired = pdFALSE;
\r
1185 /* Move any readied tasks from the pending list into the
\r
1186 appropriate ready list. */
\r
1187 while( ( pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xPendingReadyList ) ) ) != NULL )
\r
1189 vListRemove( &( pxTCB->xEventListItem ) );
\r
1190 vListRemove( &( pxTCB->xGenericListItem ) );
\r
1191 prvAddTaskToReadyQueue( pxTCB );
\r
1193 /* If we have moved a task that has a priority higher than
\r
1194 the current task then we should yield. */
\r
1195 if( pxTCB->uxPriority >= pxCurrentTCB->uxPriority )
\r
1197 xYieldRequired = pdTRUE;
\r
1201 /* If any ticks occurred while the scheduler was suspended then
\r
1202 they should be processed now. This ensures the tick count does not
\r
1203 slip, and that any delayed tasks are resumed at the correct time. */
\r
1204 if( uxMissedTicks > ( unsigned portBASE_TYPE ) 0 )
\r
1206 while( uxMissedTicks > ( unsigned portBASE_TYPE ) 0 )
\r
1208 vTaskIncrementTick();
\r
1212 /* As we have processed some ticks it is appropriate to yield
\r
1213 to ensure the highest priority task that is ready to run is
\r
1214 the task actually running. */
\r
1215 xYieldRequired = pdTRUE;
\r
1218 if( ( xYieldRequired == pdTRUE ) || ( xMissedYield == pdTRUE ) )
\r
1220 xAlreadyYielded = pdTRUE;
\r
1221 xMissedYield = pdFALSE;
\r
1227 portEXIT_CRITICAL();
\r
1229 return xAlreadyYielded;
\r
1237 /*-----------------------------------------------------------
\r
1238 * PUBLIC TASK UTILITIES documented in task.h
\r
1239 *----------------------------------------------------------*/
\r
1243 portTickType xTaskGetTickCount( void )
\r
1245 portTickType xTicks;
\r
1247 /* Critical section required if running on a 16 bit processor. */
\r
1248 taskENTER_CRITICAL();
\r
1250 xTicks = xTickCount;
\r
1252 taskEXIT_CRITICAL();
\r
1256 /*-----------------------------------------------------------*/
\r
1258 unsigned portBASE_TYPE uxTaskGetNumberOfTasks( void )
\r
1260 unsigned portBASE_TYPE uxNumberOfTasks;
\r
1262 taskENTER_CRITICAL();
\r
1263 uxNumberOfTasks = uxCurrentNumberOfTasks;
\r
1264 taskEXIT_CRITICAL();
\r
1266 return uxNumberOfTasks;
\r
1268 /*-----------------------------------------------------------*/
\r
1270 #if ( ( configUSE_TRACE_FACILITY == 1 ) && ( INCLUDE_vTaskDelete == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
\r
1272 void vTaskList( signed portCHAR *pcWriteBuffer )
\r
1274 unsigned portBASE_TYPE uxQueue;
\r
1276 /* This is a VERY costly function that should be used for debug only.
\r
1277 It leaves interrupts disabled for a LONG time. */
\r
1279 vTaskSuspendAll();
\r
1281 /* Run through all the lists that could potentially contain a TCB and
\r
1282 report the task name, state and stack high water mark. */
\r
1284 pcWriteBuffer[ 0 ] = ( signed portCHAR ) 0x00;
\r
1285 strcat( ( portCHAR * ) pcWriteBuffer, ( const portCHAR * ) "\r\n" );
\r
1287 uxQueue = uxTopUsedPriority + 1;
\r
1293 if( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxQueue ] ) ) )
\r
1295 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &( pxReadyTasksLists[ uxQueue ] ), tskREADY_CHAR );
\r
1297 }while( uxQueue > ( unsigned portSHORT ) tskIDLE_PRIORITY );
\r
1299 if( !listLIST_IS_EMPTY( pxDelayedTaskList ) )
\r
1301 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) pxDelayedTaskList, tskBLOCKED_CHAR );
\r
1304 if( !listLIST_IS_EMPTY( pxOverflowDelayedTaskList ) )
\r
1306 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) pxOverflowDelayedTaskList, tskBLOCKED_CHAR );
\r
1309 if( !listLIST_IS_EMPTY( &xTasksWaitingTermination ) )
\r
1311 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &xTasksWaitingTermination, tskDELETED_CHAR );
\r
1314 if( !listLIST_IS_EMPTY( &xSuspendedTaskList ) )
\r
1316 prvListTaskWithinSingleList( pcWriteBuffer, ( xList * ) &xSuspendedTaskList, tskSUSPENDED_CHAR );
\r
1323 /*----------------------------------------------------------*/
\r
1325 #if ( configUSE_TRACE_FACILITY == 1 )
\r
1327 void vTaskStartTrace( signed portCHAR * pcBuffer, unsigned portLONG ulBufferSize )
\r
1329 portENTER_CRITICAL();
\r
1331 pcTraceBuffer = ( volatile signed portCHAR * volatile )pcBuffer;
\r
1332 pcTraceBufferStart = pcBuffer;
\r
1333 pcTraceBufferEnd = pcBuffer + ( ulBufferSize - tskSIZE_OF_EACH_TRACE_LINE );
\r
1334 xTracing = pdTRUE;
\r
1336 portEXIT_CRITICAL();
\r
1340 /*----------------------------------------------------------*/
\r
1342 #if ( configUSE_TRACE_FACILITY == 1 )
\r
1344 unsigned portLONG ulTaskEndTrace( void )
\r
1346 unsigned portLONG ulBufferLength;
\r
1348 portENTER_CRITICAL();
\r
1349 xTracing = pdFALSE;
\r
1350 portEXIT_CRITICAL();
\r
1352 ulBufferLength = ( unsigned portLONG ) ( pcTraceBuffer - pcTraceBufferStart );
\r
1354 return ulBufferLength;
\r
1361 /*-----------------------------------------------------------
\r
1362 * SCHEDULER INTERNALS AVAILABLE FOR PORTING PURPOSES
\r
1363 * documented in task.h
\r
1364 *----------------------------------------------------------*/
\r
1367 inline void vTaskIncrementTick( void )
\r
1369 /* Called by the portable layer each time a tick interrupt occurs.
\r
1370 Increments the tick then checks to see if the new tick value will cause any
\r
1371 tasks to be unblocked. */
\r
1372 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
\r
1375 if( xTickCount == ( portTickType ) 0 )
\r
1379 /* Tick count has overflowed so we need to swap the delay lists.
\r
1380 If there are any items in pxDelayedTaskList here then there is
\r
1382 pxTemp = pxDelayedTaskList;
\r
1383 pxDelayedTaskList = pxOverflowDelayedTaskList;
\r
1384 pxOverflowDelayedTaskList = pxTemp;
\r
1385 xNumOfOverflows++;
\r
1388 /* See if this tick has made a timeout expire. */
\r
1389 prvCheckDelayedTasks();
\r
1395 /* The tick hook gets called at regular intervals, even if the
\r
1396 scheduler is locked. */
\r
1397 #if ( configUSE_TICK_HOOK == 1 )
\r
1399 extern void vApplicationTickHook( void );
\r
1401 vApplicationTickHook();
\r
1406 #if ( configUSE_TICK_HOOK == 1 )
\r
1408 extern void vApplicationTickHook( void );
\r
1410 /* Guard against the tick hook being called when the missed tick
\r
1411 count is being unwound (when the scheduler is being unlocked. */
\r
1412 if( uxMissedTicks == 0 )
\r
1414 vApplicationTickHook();
\r
1419 /*-----------------------------------------------------------*/
\r
1421 #if ( ( INCLUDE_vTaskCleanUpResources == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
\r
1423 void vTaskCleanUpResources( void )
\r
1425 unsigned portSHORT usQueue;
\r
1426 volatile tskTCB *pxTCB;
\r
1428 usQueue = ( unsigned portSHORT ) uxTopUsedPriority + ( unsigned portSHORT ) 1;
\r
1430 /* Remove any TCB's from the ready queues. */
\r
1435 while( !listLIST_IS_EMPTY( &( pxReadyTasksLists[ usQueue ] ) ) )
\r
1437 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &( pxReadyTasksLists[ usQueue ] ) );
\r
1438 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
\r
1440 prvDeleteTCB( ( tskTCB * ) pxTCB );
\r
1442 }while( usQueue > ( unsigned portSHORT ) tskIDLE_PRIORITY );
\r
1444 /* Remove any TCB's from the delayed queue. */
\r
1445 while( !listLIST_IS_EMPTY( &xDelayedTaskList1 ) )
\r
1447 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xDelayedTaskList1 );
\r
1448 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
\r
1450 prvDeleteTCB( ( tskTCB * ) pxTCB );
\r
1453 /* Remove any TCB's from the overflow delayed queue. */
\r
1454 while( !listLIST_IS_EMPTY( &xDelayedTaskList2 ) )
\r
1456 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xDelayedTaskList2 );
\r
1457 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
\r
1459 prvDeleteTCB( ( tskTCB * ) pxTCB );
\r
1462 while( !listLIST_IS_EMPTY( &xSuspendedTaskList ) )
\r
1464 listGET_OWNER_OF_NEXT_ENTRY( pxTCB, &xSuspendedTaskList );
\r
1465 vListRemove( ( xListItem * ) &( pxTCB->xGenericListItem ) );
\r
1467 prvDeleteTCB( ( tskTCB * ) pxTCB );
\r
1472 /*-----------------------------------------------------------*/
\r
1474 void vTaskSwitchContext( void )
\r
1476 if( uxSchedulerSuspended != ( unsigned portBASE_TYPE ) pdFALSE )
\r
1478 /* The scheduler is currently suspended - do not allow a context
\r
1480 xMissedYield = pdTRUE;
\r
1484 /* Find the highest priority queue that contains ready tasks. */
\r
1485 while( listLIST_IS_EMPTY( &( pxReadyTasksLists[ uxTopReadyPriority ] ) ) )
\r
1487 --uxTopReadyPriority;
\r
1490 /* listGET_OWNER_OF_NEXT_ENTRY walks through the list, so the tasks of the
\r
1491 same priority get an equal share of the processor time. */
\r
1492 listGET_OWNER_OF_NEXT_ENTRY( pxCurrentTCB, &( pxReadyTasksLists[ uxTopReadyPriority ] ) );
\r
1493 vWriteTraceToBuffer();
\r
1495 /*-----------------------------------------------------------*/
\r
1497 void vTaskPlaceOnEventList( const xList * const pxEventList, portTickType xTicksToWait )
\r
1499 portTickType xTimeToWake;
\r
1501 /* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
\r
1502 SCHEDULER SUSPENDED. */
\r
1504 /* Place the event list item of the TCB in the appropriate event list.
\r
1505 This is placed in the list in priority order so the highest priority task
\r
1506 is the first to be woken by the event. */
\r
1507 vListInsert( ( xList * ) pxEventList, ( xListItem * ) &( pxCurrentTCB->xEventListItem ) );
\r
1509 /* We must remove ourselves from the ready list before adding ourselves
\r
1510 to the blocked list as the same list item is used for both lists. We have
\r
1511 exclusive access to the ready lists as the scheduler is locked. */
\r
1512 vListRemove( ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
1515 #if ( INCLUDE_vTaskSuspend == 1 )
\r
1517 if( xTicksToWait == portMAX_DELAY )
\r
1519 /* Add ourselves to the suspended task list instead of a delayed task
\r
1520 list to ensure we are not woken by a timing event. We will block
\r
1522 vListInsertEnd( ( xList * ) &xSuspendedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
1526 /* Calculate the time at which the task should be woken if the event does
\r
1527 not occur. This may overflow but this doesn't matter. */
\r
1528 xTimeToWake = xTickCount + xTicksToWait;
\r
1530 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
\r
1532 if( xTimeToWake < xTickCount )
\r
1534 /* Wake time has overflowed. Place this item in the overflow list. */
\r
1535 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
1539 /* The wake time has not overflowed, so we can use the current block list. */
\r
1540 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
1546 /* Calculate the time at which the task should be woken if the event does
\r
1547 not occur. This may overflow but this doesn't matter. */
\r
1548 xTimeToWake = xTickCount + xTicksToWait;
\r
1550 listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xGenericListItem ), xTimeToWake );
\r
1552 if( xTimeToWake < xTickCount )
\r
1554 /* Wake time has overflowed. Place this item in the overflow list. */
\r
1555 vListInsert( ( xList * ) pxOverflowDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
1559 /* The wake time has not overflowed, so we can use the current block list. */
\r
1560 vListInsert( ( xList * ) pxDelayedTaskList, ( xListItem * ) &( pxCurrentTCB->xGenericListItem ) );
\r
1565 /*-----------------------------------------------------------*/
\r
1567 signed portBASE_TYPE xTaskRemoveFromEventList( const xList * const pxEventList )
\r
1569 tskTCB *pxUnblockedTCB;
\r
1570 portBASE_TYPE xReturn;
\r
1572 /* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
\r
1573 SCHEDULER SUSPENDED. It can also be called from within an ISR. */
\r
1575 /* The event list is sorted in priority order, so we can remove the
\r
1576 first in the list, remove the TCB from the delayed list, and add
\r
1577 it to the ready list.
\r
1579 If an event is for a queue that is locked then this function will never
\r
1580 get called - the lock count on the queue will get modified instead. This
\r
1581 means we can always expect exclusive access to the event list here. */
\r
1582 pxUnblockedTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxEventList );
\r
1583 vListRemove( &( pxUnblockedTCB->xEventListItem ) );
\r
1585 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
\r
1587 vListRemove( &( pxUnblockedTCB->xGenericListItem ) );
\r
1588 prvAddTaskToReadyQueue( pxUnblockedTCB );
\r
1592 /* We cannot access the delayed or ready lists, so will hold this
\r
1593 task pending until the scheduler is resumed. */
\r
1594 vListInsertEnd( ( xList * ) &( xPendingReadyList ), &( pxUnblockedTCB->xEventListItem ) );
\r
1597 if( pxUnblockedTCB->uxPriority >= pxCurrentTCB->uxPriority )
\r
1599 /* Return true if the task removed from the event list has
\r
1600 a higher priority than the calling task. This allows
\r
1601 the calling task to know if it should force a context
\r
1607 xReturn = pdFALSE;
\r
1612 /*-----------------------------------------------------------*/
\r
1614 void vTaskSetTimeOutState( xTimeOutType * const pxTimeOut )
\r
1616 pxTimeOut->xOverflowCount = xNumOfOverflows;
\r
1617 pxTimeOut->xTimeOnEntering = xTickCount;
\r
1619 /*-----------------------------------------------------------*/
\r
1621 portBASE_TYPE xTaskCheckForTimeOut( xTimeOutType * const pxTimeOut, portTickType * const pxTicksToWait )
\r
1623 portBASE_TYPE xReturn;
\r
1625 #if ( INCLUDE_vTaskSuspend == 1 )
\r
1626 /* If INCLUDE_vTaskSuspend is set to 1 and the block time specified is
\r
1627 the maximum block time then the task should block indefinitely, and
\r
1628 therefore never time out. */
\r
1629 if( *pxTicksToWait == portMAX_DELAY )
\r
1631 xReturn = pdFALSE;
\r
1633 else /* We are not blocking indefinitely, perform the checks below. */
\r
1636 if( ( xNumOfOverflows != pxTimeOut->xOverflowCount ) && ( xTickCount >= pxTimeOut->xTimeOnEntering ) )
\r
1638 /* The tick count is greater than the time at which vTaskSetTimeout()
\r
1639 was called, but has also overflowed since vTaskSetTimeOut() was called.
\r
1640 It must have wrapped all the way around and gone past us again. This
\r
1641 passed since vTaskSetTimeout() was called. */
\r
1644 else if( ( xTickCount - pxTimeOut->xTimeOnEntering ) < *pxTicksToWait )
\r
1646 /* Not a genuine timeout. Adjust parameters for time remaining. */
\r
1647 *pxTicksToWait -= ( xTickCount - pxTimeOut->xTimeOnEntering );
\r
1648 vTaskSetTimeOutState( pxTimeOut );
\r
1649 xReturn = pdFALSE;
\r
1658 /*-----------------------------------------------------------*/
\r
1660 void vTaskMissedYield( void )
\r
1662 xMissedYield = pdTRUE;
\r
1666 * -----------------------------------------------------------
\r
1668 * ----------------------------------------------------------
\r
1670 * The portTASK_FUNCTION() macro is used to allow port/compiler specific
\r
1671 * language extensions. The equivalent prototype for this function is:
\r
1673 * void prvIdleTask( void *pvParameters );
\r
1676 static portTASK_FUNCTION( prvIdleTask, pvParameters )
\r
1678 /* Stop warnings. */
\r
1679 ( void ) pvParameters;
\r
1683 /* See if any tasks have been deleted. */
\r
1684 prvCheckTasksWaitingTermination();
\r
1686 #if ( configUSE_PREEMPTION == 0 )
\r
1688 /* If we are not using preemption we keep forcing a task switch to
\r
1689 see if any other task has become available. If we are using
\r
1690 preemption we don't need to do this as any task becoming available
\r
1691 will automatically get the processor anyway. */
\r
1696 #if ( ( configUSE_PREEMPTION == 1 ) && ( configIDLE_SHOULD_YIELD == 1 ) )
\r
1698 /* When using preemption tasks of equal priority will be
\r
1699 timesliced. If a task that is sharing the idle priority is ready
\r
1700 to run then the idle task should yield before the end of the
\r
1703 A critical region is not required here as we are just reading from
\r
1704 the list, and an occasional incorrect value will not matter. If
\r
1705 the ready list at the idle priority contains more than one task
\r
1706 then a task other than the idle task is ready to execute. */
\r
1707 if( listCURRENT_LIST_LENGTH( &( pxReadyTasksLists[ tskIDLE_PRIORITY ] ) ) > ( unsigned portBASE_TYPE ) 1 )
\r
1714 #if ( configUSE_IDLE_HOOK == 1 )
\r
1716 extern void vApplicationIdleHook( void );
\r
1718 /* Call the user defined function from within the idle task. This
\r
1719 allows the application designer to add background functionality
\r
1720 without the overhead of a separate task.
\r
1721 NOTE: vApplicationIdleHook() MUST NOT, UNDER ANY CIRCUMSTANCES,
\r
1722 CALL A FUNCTION THAT MIGHT BLOCK. */
\r
1723 vApplicationIdleHook();
\r
1727 } /*lint !e715 pvParameters is not accessed but all task functions require the same prototype. */
\r
1735 /*-----------------------------------------------------------
\r
1736 * File private functions documented at the top of the file.
\r
1737 *----------------------------------------------------------*/
\r
1741 static void prvInitialiseTCBVariables( tskTCB *pxTCB, const signed portCHAR * const pcName, unsigned portBASE_TYPE uxPriority )
\r
1743 /* Store the function name in the TCB. */
\r
1744 strncpy( ( char * ) pxTCB->pcTaskName, ( const char * ) pcName, ( unsigned portSHORT ) configMAX_TASK_NAME_LEN );
\r
1745 pxTCB->pcTaskName[ ( unsigned portSHORT ) configMAX_TASK_NAME_LEN - ( unsigned portSHORT ) 1 ] = '\0';
\r
1747 /* This is used as an array index so must ensure it's not too large. */
\r
1748 if( uxPriority >= configMAX_PRIORITIES )
\r
1750 uxPriority = configMAX_PRIORITIES - 1;
\r
1753 pxTCB->uxPriority = uxPriority;
\r
1754 #if ( configUSE_MUTEXES == 1 )
\r
1756 pxTCB->uxBasePriority = uxPriority;
\r
1760 vListInitialiseItem( &( pxTCB->xGenericListItem ) );
\r
1761 vListInitialiseItem( &( pxTCB->xEventListItem ) );
\r
1763 /* Set the pxTCB as a link back from the xListItem. This is so we can get
\r
1764 back to the containing TCB from a generic item in a list. */
\r
1765 listSET_LIST_ITEM_OWNER( &( pxTCB->xGenericListItem ), pxTCB );
\r
1767 /* Event lists are always in priority order. */
\r
1768 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) uxPriority );
\r
1769 listSET_LIST_ITEM_OWNER( &( pxTCB->xEventListItem ), pxTCB );
\r
1771 /*-----------------------------------------------------------*/
\r
1773 static void prvInitialiseTaskLists( void )
\r
1775 unsigned portBASE_TYPE uxPriority;
\r
1777 for( uxPriority = 0; uxPriority < configMAX_PRIORITIES; uxPriority++ )
\r
1779 vListInitialise( ( xList * ) &( pxReadyTasksLists[ uxPriority ] ) );
\r
1782 vListInitialise( ( xList * ) &xDelayedTaskList1 );
\r
1783 vListInitialise( ( xList * ) &xDelayedTaskList2 );
\r
1784 vListInitialise( ( xList * ) &xPendingReadyList );
\r
1786 #if ( INCLUDE_vTaskDelete == 1 )
\r
1788 vListInitialise( ( xList * ) &xTasksWaitingTermination );
\r
1792 #if ( INCLUDE_vTaskSuspend == 1 )
\r
1794 vListInitialise( ( xList * ) &xSuspendedTaskList );
\r
1798 /* Start with pxDelayedTaskList using list1 and the pxOverflowDelayedTaskList
\r
1800 pxDelayedTaskList = &xDelayedTaskList1;
\r
1801 pxOverflowDelayedTaskList = &xDelayedTaskList2;
\r
1803 /*-----------------------------------------------------------*/
\r
1805 static void prvCheckTasksWaitingTermination( void )
\r
1807 #if ( INCLUDE_vTaskDelete == 1 )
\r
1809 portBASE_TYPE xListIsEmpty;
\r
1811 /* ucTasksDeleted is used to prevent vTaskSuspendAll() being called
\r
1812 too often in the idle task. */
\r
1813 if( uxTasksDeleted > ( unsigned portBASE_TYPE ) 0 )
\r
1815 vTaskSuspendAll();
\r
1816 xListIsEmpty = listLIST_IS_EMPTY( &xTasksWaitingTermination );
\r
1819 if( !xListIsEmpty )
\r
1823 portENTER_CRITICAL();
\r
1825 pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xTasksWaitingTermination ) );
\r
1826 vListRemove( &( pxTCB->xGenericListItem ) );
\r
1827 --uxCurrentNumberOfTasks;
\r
1830 portEXIT_CRITICAL();
\r
1832 prvDeleteTCB( pxTCB );
\r
1838 /*-----------------------------------------------------------*/
\r
1840 static tskTCB *prvAllocateTCBAndStack( unsigned portSHORT usStackDepth )
\r
1844 /* Allocate space for the TCB. Where the memory comes from depends on
\r
1845 the implementation of the port malloc function. */
\r
1846 pxNewTCB = ( tskTCB * ) pvPortMalloc( sizeof( tskTCB ) );
\r
1848 if( pxNewTCB != NULL )
\r
1850 /* Allocate space for the stack used by the task being created.
\r
1851 The base of the stack memory stored in the TCB so the task can
\r
1852 be deleted later if required. */
\r
1853 pxNewTCB->pxStack = ( portSTACK_TYPE * ) pvPortMalloc( ( ( size_t )usStackDepth ) * sizeof( portSTACK_TYPE ) );
\r
1855 if( pxNewTCB->pxStack == NULL )
\r
1857 /* Could not allocate the stack. Delete the allocated TCB. */
\r
1858 vPortFree( pxNewTCB );
\r
1863 /* Just to help debugging. */
\r
1864 memset( pxNewTCB->pxStack, tskSTACK_FILL_BYTE, usStackDepth * sizeof( portSTACK_TYPE ) );
\r
1870 /*-----------------------------------------------------------*/
\r
1872 #if ( configUSE_TRACE_FACILITY == 1 )
\r
1874 static void prvListTaskWithinSingleList( const signed portCHAR *pcWriteBuffer, xList *pxList, signed portCHAR cStatus )
\r
1876 volatile tskTCB *pxNextTCB, *pxFirstTCB;
\r
1877 static portCHAR pcStatusString[ 50 ];
\r
1878 unsigned portSHORT usStackRemaining;
\r
1880 /* Write the details of all the TCB's in pxList into the buffer. */
\r
1881 listGET_OWNER_OF_NEXT_ENTRY( pxFirstTCB, pxList );
\r
1884 listGET_OWNER_OF_NEXT_ENTRY( pxNextTCB, pxList );
\r
1885 usStackRemaining = usTaskCheckFreeStackSpace( ( unsigned portCHAR * ) pxNextTCB->pxStack );
\r
1886 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 );
\r
1887 strcat( ( portCHAR * ) pcWriteBuffer, ( portCHAR * ) pcStatusString );
\r
1889 } while( pxNextTCB != pxFirstTCB );
\r
1893 /*-----------------------------------------------------------*/
\r
1895 #if ( configUSE_TRACE_FACILITY == 1 )
\r
1896 unsigned portSHORT usTaskCheckFreeStackSpace( const unsigned portCHAR * pucStackByte )
\r
1898 register unsigned portSHORT usCount = 0;
\r
1900 while( *pucStackByte == tskSTACK_FILL_BYTE )
\r
1902 pucStackByte -= portSTACK_GROWTH;
\r
1906 usCount /= sizeof( portSTACK_TYPE );
\r
1911 /*-----------------------------------------------------------*/
\r
1915 #if ( ( INCLUDE_vTaskDelete == 1 ) || ( INCLUDE_vTaskCleanUpResources == 1 ) )
\r
1917 static void prvDeleteTCB( tskTCB *pxTCB )
\r
1919 /* Free up the memory allocated by the scheduler for the task. It is up to
\r
1920 the task to free any memory allocated at the application level. */
\r
1921 vPortFree( pxTCB->pxStack );
\r
1922 vPortFree( pxTCB );
\r
1928 /*-----------------------------------------------------------*/
\r
1930 #if ( INCLUDE_xTaskGetCurrentTaskHandle == 1 )
\r
1932 xTaskHandle xTaskGetCurrentTaskHandle( void )
\r
1934 xTaskHandle xReturn;
\r
1936 portENTER_CRITICAL();
\r
1938 xReturn = ( xTaskHandle ) pxCurrentTCB;
\r
1940 portEXIT_CRITICAL();
\r
1947 /*-----------------------------------------------------------*/
\r
1949 #if ( INCLUDE_xTaskGetSchedulerState == 1 )
\r
1951 portBASE_TYPE xTaskGetSchedulerState( void )
\r
1953 portBASE_TYPE xReturn;
\r
1955 if( xSchedulerRunning == pdFALSE )
\r
1957 xReturn = taskSCHEDULER_NOT_STARTED;
\r
1961 if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
\r
1963 xReturn = taskSCHEDULER_RUNNING;
\r
1967 xReturn = taskSCHEDULER_SUSPENDED;
\r
1976 #if ( configUSE_MUTEXES == 1 )
\r
1978 void vTaskPriorityInherit( xTaskHandle * const pxMutexHolder )
\r
1980 tskTCB * const pxTCB = ( tskTCB * ) pxMutexHolder;
\r
1982 if( pxTCB->uxPriority < pxCurrentTCB->uxPriority )
\r
1984 /* Adjust the mutex holder state to account for its new priority. */
\r
1985 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) pxCurrentTCB->uxPriority );
\r
1987 /* If the task being modified is in the read state it will need to
\r
1988 be moved in to a new list. */
\r
1989 if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ pxTCB->uxPriority ] ), &( pxTCB->xGenericListItem ) ) )
\r
1991 vListRemove( &( pxTCB->xGenericListItem ) );
\r
1993 /* Inherit the priority before being moved into the new list. */
\r
1994 pxTCB->uxPriority = pxCurrentTCB->uxPriority;
\r
1995 prvAddTaskToReadyQueue( pxTCB );
\r
1999 /* Just inherit the priority. */
\r
2000 pxTCB->uxPriority = pxCurrentTCB->uxPriority;
\r
2007 #if ( configUSE_MUTEXES == 1 )
\r
2009 void vTaskPriorityDisinherit( xTaskHandle * const pxMutexHolder )
\r
2011 tskTCB * const pxTCB = ( tskTCB * ) pxMutexHolder;
\r
2013 if( pxMutexHolder != NULL )
\r
2015 if( pxTCB->uxPriority != pxTCB->uxBasePriority )
\r
2017 /* We must be the running task to be able to give the mutex back.
\r
2018 Remove ourselves from the ready list we currently appear in. */
\r
2019 vListRemove( &( pxTCB->xGenericListItem ) );
\r
2021 /* Disinherit the priority before adding ourselves into the new
\r
2023 pxTCB->uxPriority = pxTCB->uxBasePriority;
\r
2024 listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) pxTCB->uxPriority );
\r
2025 prvAddTaskToReadyQueue( pxTCB );
\r