in tasks.c [1520:1679]
void vTaskPrioritySet( TaskHandle_t xTask,
UBaseType_t uxNewPriority )
{
TCB_t * pxTCB;
UBaseType_t uxCurrentBasePriority, uxPriorityUsedOnEntry;
BaseType_t xYieldRequired = pdFALSE;
configASSERT( uxNewPriority < configMAX_PRIORITIES );
/* Ensure the new priority is valid. */
if( uxNewPriority >= ( UBaseType_t ) configMAX_PRIORITIES )
{
uxNewPriority = ( UBaseType_t ) configMAX_PRIORITIES - ( UBaseType_t ) 1U;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
taskENTER_CRITICAL();
{
/* If null is passed in here then it is the priority of the calling
* task that is being changed. */
pxTCB = prvGetTCBFromHandle( xTask );
traceTASK_PRIORITY_SET( pxTCB, uxNewPriority );
#if ( configUSE_MUTEXES == 1 )
{
uxCurrentBasePriority = pxTCB->uxBasePriority;
}
#else
{
uxCurrentBasePriority = pxTCB->uxPriority;
}
#endif
if( uxCurrentBasePriority != uxNewPriority )
{
/* The priority change may have readied a task of higher
* priority than the calling task. */
if( uxNewPriority > uxCurrentBasePriority )
{
if( pxTCB != pxCurrentTCB )
{
/* The priority of a task other than the currently
* running task is being raised. Is the priority being
* raised above that of the running task? */
if( uxNewPriority >= pxCurrentTCB->uxPriority )
{
xYieldRequired = pdTRUE;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
else
{
/* The priority of the running task is being raised,
* but the running task must already be the highest
* priority task able to run so no yield is required. */
}
}
else if( pxTCB == pxCurrentTCB )
{
/* Setting the priority of the running task down means
* there may now be another task of higher priority that
* is ready to execute. */
xYieldRequired = pdTRUE;
}
else
{
/* Setting the priority of any other task down does not
* require a yield as the running task must be above the
* new priority of the task being modified. */
}
/* Remember the ready list the task might be referenced from
* before its uxPriority member is changed so the
* taskRESET_READY_PRIORITY() macro can function correctly. */
uxPriorityUsedOnEntry = pxTCB->uxPriority;
#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;
}
else
{
mtCOVERAGE_TEST_MARKER();
}
/* The base priority gets set whatever. */
pxTCB->uxBasePriority = uxNewPriority;
}
#else /* if ( configUSE_MUTEXES == 1 ) */
{
pxTCB->uxPriority = uxNewPriority;
}
#endif /* if ( configUSE_MUTEXES == 1 ) */
/* Only reset the event list item value if the value is not
* being used for anything else. */
if( ( listGET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ) ) & taskEVENT_LIST_ITEM_VALUE_IN_USE ) == 0UL )
{
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), ( ( TickType_t ) configMAX_PRIORITIES - ( TickType_t ) uxNewPriority ) ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
}
else
{
mtCOVERAGE_TEST_MARKER();
}
/* If the task is in the blocked or suspended list we need do
* nothing more than change its priority variable. However, if
* the task is in a ready list it needs to be removed and placed
* in the list appropriate to its new priority. */
if( listIS_CONTAINED_WITHIN( &( pxReadyTasksLists[ uxPriorityUsedOnEntry ] ), &( pxTCB->xStateListItem ) ) != pdFALSE )
{
/* The task is currently in its ready list - remove before
* adding it to its new ready list. As we are in a critical
* section we can do this even if the scheduler is suspended. */
if( uxListRemove( &( pxTCB->xStateListItem ) ) == ( UBaseType_t ) 0 )
{
/* It is known that the task is in its ready list so
* there is no need to check again and the port level
* reset macro can be called directly. */
portRESET_READY_PRIORITY( uxPriorityUsedOnEntry, uxTopReadyPriority );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
prvAddTaskToReadyList( pxTCB );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
if( xYieldRequired != pdFALSE )
{
taskYIELD_IF_USING_PREEMPTION();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
/* Remove compiler warning about unused variables when the port
* optimised task selection is not being used. */
( void ) uxPriorityUsedOnEntry;
}
}
taskEXIT_CRITICAL();
}