/**
* @brief Finalize a blocking operation.
*
* This method is used to finalize a blocking operation that was
* satisfied. It may be used with thread queues or any other synchronization
* object that uses the blocking states and watchdog times for timeout.
*
* This method will restore the previous ISR disable level during the cancel
* operation. Thus it is an implicit _ISR_Enable().
*
* @param[in] the_thread is the thread whose blocking is canceled
* @param[in] lock_context is the previous ISR disable level
*/
static void _Thread_blocking_operation_Finalize(
Thread_Control *the_thread,
ISR_lock_Context *lock_context
)
{
/*
* The thread is not waiting on anything after this completes.
*/
the_thread->Wait.queue = NULL;
/*
* If the sync state is timed out, this is very likely not needed.
* But better safe than sorry when it comes to critical sections.
*/
if ( _Watchdog_Is_active( &the_thread->Timer ) ) {
_Watchdog_Deactivate( &the_thread->Timer );
_Thread_queue_Release( lock_context );
(void) _Watchdog_Remove( &the_thread->Timer );
} else
_Thread_queue_Release( lock_context );
/*
* Global objects with thread queue's should not be operated on from an
* ISR. But the sync code still must allow short timeouts to be processed
* correctly.
*/
_Thread_Unblock( the_thread );
#if defined(RTEMS_MULTIPROCESSING)
if ( !_Objects_Is_local_id( the_thread->Object.id ) )
_Thread_MP_Free_proxy( the_thread );
#endif
}
Thread_Control *_Thread_queue_Dequeue_fifo(
Thread_queue_Control *the_thread_queue
)
{
ISR_Level level;
Thread_Control *the_thread;
_ISR_Disable( level );
if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) ) {
the_thread = (Thread_Control *)
_Chain_Get_first_unprotected( &the_thread_queue->Queues.Fifo );
the_thread->Wait.queue = NULL;
if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
_ISR_Enable( level );
_Thread_Unblock( the_thread );
} else {
_Watchdog_Deactivate( &the_thread->Timer );
_ISR_Enable( level );
(void) _Watchdog_Remove( &the_thread->Timer );
_Thread_Unblock( the_thread );
}
#if defined(RTEMS_MULTIPROCESSING)
if ( !_Objects_Is_local_id( the_thread->Object.id ) )
_Thread_MP_Free_proxy( the_thread );
#endif
return the_thread;
}
_ISR_Enable( level );
return NULL;
}
void _Event_Surrender(
Thread_Control *the_thread
)
{
ISR_Level level;
rtems_event_set pending_events;
rtems_event_set event_condition;
rtems_event_set seized_events;
rtems_option option_set;
RTEMS_API_Control *api;
api = the_thread->API_Extensions[ THREAD_API_RTEMS ];
option_set = (rtems_option) the_thread->Wait.option;
_ISR_Disable( level );
pending_events = api->pending_events;
event_condition = (rtems_event_set) the_thread->Wait.count;
seized_events = _Event_sets_Get( pending_events, event_condition );
/*
* No events were seized in this operation
*/
if ( _Event_sets_Is_empty( seized_events ) ) {
_ISR_Enable( level );
return;
}
/*
* If we are in an ISR and sending to the current thread, then
* we have a critical section issue to deal with.
*/
if ( _ISR_Is_in_progress() &&
_Thread_Is_executing( the_thread ) &&
((_Event_Sync_state == THREAD_BLOCKING_OPERATION_TIMEOUT) ||
(_Event_Sync_state == THREAD_BLOCKING_OPERATION_NOTHING_HAPPENED)) ) {
if ( seized_events == event_condition || _Options_Is_any(option_set) ) {
api->pending_events = _Event_sets_Clear( pending_events,seized_events );
the_thread->Wait.count = 0;
*(rtems_event_set *)the_thread->Wait.return_argument = seized_events;
_Event_Sync_state = THREAD_BLOCKING_OPERATION_SATISFIED;
}
_ISR_Enable( level );
return;
}
/*
* Otherwise, this is a normal send to another thread
*/
if ( _States_Is_waiting_for_event( the_thread->current_state ) ) {
if ( seized_events == event_condition || _Options_Is_any( option_set ) ) {
api->pending_events = _Event_sets_Clear( pending_events, seized_events );
the_thread->Wait.count = 0;
*(rtems_event_set *)the_thread->Wait.return_argument = seized_events;
_ISR_Flash( level );
if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
_ISR_Enable( level );
_Thread_Unblock( the_thread );
} else {
_Watchdog_Deactivate( &the_thread->Timer );
_ISR_Enable( level );
(void) _Watchdog_Remove( &the_thread->Timer );
_Thread_Unblock( the_thread );
}
return;
}
}
_ISR_Enable( level );
}
Thread_Control *_Thread_queue_Dequeue_priority(
Thread_queue_Control *the_thread_queue
)
{
uint32_t index;
ISR_Level level;
Thread_Control *the_thread = NULL; /* just to remove warnings */
Thread_Control *new_first_thread;
Chain_Node *head;
Chain_Node *tail;
Chain_Node *new_first_node;
Chain_Node *new_second_node;
Chain_Node *last_node;
Chain_Node *next_node;
Chain_Node *previous_node;
_ISR_Disable( level );
for( index=0 ;
index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ;
index++ ) {
if ( !_Chain_Is_empty( &the_thread_queue->Queues.Priority[ index ] ) ) {
the_thread = (Thread_Control *) _Chain_First(
&the_thread_queue->Queues.Priority[ index ]
);
goto dequeue;
}
}
/*
* We did not find a thread to unblock.
*/
_ISR_Enable( level );
return NULL;
dequeue:
the_thread->Wait.queue = NULL;
new_first_node = _Chain_First( &the_thread->Wait.Block2n );
new_first_thread = (Thread_Control *) new_first_node;
next_node = the_thread->Object.Node.next;
previous_node = the_thread->Object.Node.previous;
if ( !_Chain_Is_empty( &the_thread->Wait.Block2n ) ) {
last_node = _Chain_Last( &the_thread->Wait.Block2n );
new_second_node = new_first_node->next;
previous_node->next = new_first_node;
next_node->previous = new_first_node;
new_first_node->next = next_node;
new_first_node->previous = previous_node;
if ( !_Chain_Has_only_one_node( &the_thread->Wait.Block2n ) ) {
/* > two threads on 2-n */
head = _Chain_Head( &new_first_thread->Wait.Block2n );
tail = _Chain_Tail( &new_first_thread->Wait.Block2n );
new_second_node->previous = head;
head->next = new_second_node;
tail->previous = last_node;
last_node->next = tail;
}
} else {
previous_node->next = next_node;
next_node->previous = previous_node;
}
if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
_ISR_Enable( level );
_Thread_Unblock( the_thread );
} else {
_Watchdog_Deactivate( &the_thread->Timer );
_ISR_Enable( level );
(void) _Watchdog_Remove( &the_thread->Timer );
_Thread_Unblock( the_thread );
}
#if defined(RTEMS_MULTIPROCESSING)
if ( !_Objects_Is_local_id( the_thread->Object.id ) )
_Thread_MP_Free_proxy( the_thread );
#endif
return( the_thread );
}
void _Event_Seize(
rtems_event_set event_in,
rtems_option option_set,
rtems_interval ticks,
rtems_event_set *event_out
)
{
Thread_Control *executing;
rtems_event_set seized_events;
rtems_event_set pending_events;
ISR_Level level;
RTEMS_API_Control *api;
Event_Sync_states sync_state;
executing = _Thread_Executing;
executing->Wait.return_code = RTEMS_SUCCESSFUL;
api = executing->API_Extensions[ THREAD_API_RTEMS ];
_ISR_Disable( level );
pending_events = api->pending_events;
seized_events = _Event_sets_Get( pending_events, event_in );
if ( !_Event_sets_Is_empty( seized_events ) &&
(seized_events == event_in || _Options_Is_any( option_set )) ) {
api->pending_events =
_Event_sets_Clear( pending_events, seized_events );
_ISR_Enable( level );
*event_out = seized_events;
return;
}
if ( _Options_Is_no_wait( option_set ) ) {
_ISR_Enable( level );
executing->Wait.return_code = RTEMS_UNSATISFIED;
*event_out = seized_events;
return;
}
_Event_Sync_state = EVENT_SYNC_NOTHING_HAPPENED;
executing->Wait.option = (uint32_t ) option_set;
executing->Wait.count = (uint32_t ) event_in;
executing->Wait.return_argument = event_out;
_ISR_Enable( level );
if ( ticks ) {
_Watchdog_Initialize(
&executing->Timer,
_Event_Timeout,
executing->Object.id,
NULL
);
_Watchdog_Insert_ticks( &executing->Timer, ticks );
}
_Thread_Set_state( executing, STATES_WAITING_FOR_EVENT );
_ISR_Disable( level );
sync_state = _Event_Sync_state;
_Event_Sync_state = EVENT_SYNC_SYNCHRONIZED;
switch ( sync_state ) {
case EVENT_SYNC_SYNCHRONIZED:
/*
* This cannot happen. It indicates that this routine did not
* enter the synchronization states above.
*/
return;
case EVENT_SYNC_NOTHING_HAPPENED:
_ISR_Enable( level );
return;
case EVENT_SYNC_TIMEOUT:
executing->Wait.return_code = RTEMS_TIMEOUT;
_ISR_Enable( level );
_Thread_Unblock( executing );
return;
case EVENT_SYNC_SATISFIED:
if ( _Watchdog_Is_active( &executing->Timer ) ) {
_Watchdog_Deactivate( &executing->Timer );
_ISR_Enable( level );
(void) _Watchdog_Remove( &executing->Timer );
} else
_ISR_Enable( level );
_Thread_Unblock( executing );
return;
}
}
