rtems_status_code rtems_semaphore_flush( rtems_id id )
{
Semaphore_Control *the_semaphore;
Thread_queue_Context queue_context;
the_semaphore = _Semaphore_Get( id, &queue_context );
if ( the_semaphore == NULL ) {
#if defined(RTEMS_MULTIPROCESSING)
if ( _Semaphore_MP_Is_remote( id ) ) {
return RTEMS_ILLEGAL_ON_REMOTE_OBJECT;
}
#endif
return RTEMS_INVALID_ID;
}
_Thread_queue_Acquire_critical(
&the_semaphore->Core_control.Wait_queue,
&queue_context
);
_Thread_queue_Context_set_MP_callout(
&queue_context,
_Semaphore_MP_Send_object_was_deleted
);
switch ( the_semaphore->variant ) {
#if defined(RTEMS_SMP)
case SEMAPHORE_VARIANT_MRSP:
_Thread_queue_Release(
&the_semaphore->Core_control.Wait_queue,
&queue_context
);
return RTEMS_NOT_DEFINED;
#endif
default:
_Assert(
the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_INHERIT_PRIORITY
|| the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_PRIORITY_CEILING
|| the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_NO_PROTOCOL
|| the_semaphore->variant == SEMAPHORE_VARIANT_SIMPLE_BINARY
|| the_semaphore->variant == SEMAPHORE_VARIANT_COUNTING
);
_Thread_queue_Flush_critical(
&the_semaphore->Core_control.Wait_queue.Queue,
_Semaphore_Get_operations( the_semaphore ),
_Thread_queue_Flush_status_unavailable,
&queue_context
);
break;
}
return RTEMS_SUCCESSFUL;
}
CORE_mutex_Status _CORE_mutex_Surrender(
CORE_mutex_Control *the_mutex,
#if defined(RTEMS_MULTIPROCESSING)
Objects_Id id,
CORE_mutex_API_mp_support_callout api_mutex_mp_support,
#else
Objects_Id id __attribute__((unused)),
CORE_mutex_API_mp_support_callout api_mutex_mp_support __attribute__((unused)),
#endif
ISR_lock_Context *lock_context
)
{
Thread_Control *the_thread;
Thread_Control *holder;
holder = the_mutex->holder;
/*
* The following code allows a thread (or ISR) other than the thread
* which acquired the mutex to release that mutex. This is only
* allowed when the mutex in quetion is FIFO or simple Priority
* discipline. But Priority Ceiling or Priority Inheritance mutexes
* must be released by the thread which acquired them.
*/
if ( the_mutex->Attributes.only_owner_release ) {
if ( !_Thread_Is_executing( holder ) ) {
_ISR_lock_ISR_enable( lock_context );
return CORE_MUTEX_STATUS_NOT_OWNER_OF_RESOURCE;
}
}
_Thread_queue_Acquire_critical( &the_mutex->Wait_queue, lock_context );
/* XXX already unlocked -- not right status */
if ( !the_mutex->nest_count ) {
_Thread_queue_Release( &the_mutex->Wait_queue, lock_context );
return CORE_MUTEX_STATUS_SUCCESSFUL;
}
the_mutex->nest_count--;
if ( the_mutex->nest_count != 0 ) {
/*
* All error checking is on the locking side, so if the lock was
* allowed to acquired multiple times, then we should just deal with
* that. The RTEMS_DEBUG is just a validation.
*/
#if defined(RTEMS_DEBUG)
switch ( the_mutex->Attributes.lock_nesting_behavior ) {
case CORE_MUTEX_NESTING_ACQUIRES:
_Thread_queue_Release( &the_mutex->Wait_queue, lock_context );
return CORE_MUTEX_STATUS_SUCCESSFUL;
#if defined(RTEMS_POSIX_API)
case CORE_MUTEX_NESTING_IS_ERROR:
/* should never occur */
_Thread_queue_Release( &the_mutex->Wait_queue, lock_context );
return CORE_MUTEX_STATUS_NESTING_NOT_ALLOWED;
#endif
case CORE_MUTEX_NESTING_BLOCKS:
/* Currently no API exercises this behavior. */
break;
}
#else
_Thread_queue_Release( &the_mutex->Wait_queue, lock_context );
/* must be CORE_MUTEX_NESTING_ACQUIRES or we wouldn't be here */
return CORE_MUTEX_STATUS_SUCCESSFUL;
#endif
}
/*
* Formally release the mutex before possibly transferring it to a
* blocked thread.
*/
if ( _CORE_mutex_Is_inherit_priority( &the_mutex->Attributes ) ||
_CORE_mutex_Is_priority_ceiling( &the_mutex->Attributes ) ) {
CORE_mutex_Status pop_status =
_CORE_mutex_Pop_priority( the_mutex, holder );
if ( pop_status != CORE_MUTEX_STATUS_SUCCESSFUL ) {
_Thread_queue_Release( &the_mutex->Wait_queue, lock_context );
return pop_status;
}
holder->resource_count--;
}
the_mutex->holder = NULL;
/*
* Now we check if another thread was waiting for this mutex. If so,
* transfer the mutex to that thread.
*/
if ( ( the_thread = _Thread_queue_First_locked( &the_mutex->Wait_queue ) ) ) {
/*
* We must extract the thread now since this will restore its default
* thread lock. This is necessary to avoid a deadlock in the
* _Thread_Change_priority() below due to a recursive thread queue lock
* acquire.
*/
_Thread_queue_Extract_locked( &the_mutex->Wait_queue, the_thread );
#if defined(RTEMS_MULTIPROCESSING)
_Thread_Dispatch_disable();
if ( _Objects_Is_local_id( the_thread->Object.id ) )
#endif
{
the_mutex->holder = the_thread;
the_mutex->nest_count = 1;
switch ( the_mutex->Attributes.discipline ) {
case CORE_MUTEX_DISCIPLINES_FIFO:
case CORE_MUTEX_DISCIPLINES_PRIORITY:
break;
case CORE_MUTEX_DISCIPLINES_PRIORITY_INHERIT:
_CORE_mutex_Push_priority( the_mutex, the_thread );
the_thread->resource_count++;
break;
case CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING:
_CORE_mutex_Push_priority( the_mutex, the_thread );
the_thread->resource_count++;
_Thread_Raise_priority(
the_thread,
the_mutex->Attributes.priority_ceiling
);
break;
}
}
_Thread_queue_Unblock_critical(
&the_mutex->Wait_queue,
the_thread,
lock_context
);
#if defined(RTEMS_MULTIPROCESSING)
if ( !_Objects_Is_local_id( the_thread->Object.id ) ) {
the_mutex->holder = NULL;
the_mutex->nest_count = 1;
( *api_mutex_mp_support)( the_thread, id );
}
_Thread_Dispatch_enable( _Per_CPU_Get() );
#endif
} else {
_Thread_queue_Release( &the_mutex->Wait_queue, lock_context );
}
/*
* Whether or not someone is waiting for the mutex, an
* inherited priority must be lowered if this is the last
* mutex (i.e. resource) this task has.
*/
if ( !_Thread_Owns_resources( holder ) ) {
/*
* Ensure that the holder resource count is visible to all other processors
* and that we read the latest priority restore hint.
*/
_Atomic_Fence( ATOMIC_ORDER_ACQ_REL );
if ( holder->priority_restore_hint ) {
Per_CPU_Control *cpu_self;
cpu_self = _Thread_Dispatch_disable();
_Thread_Restore_priority( holder );
_Thread_Dispatch_enable( cpu_self );
}
}
return CORE_MUTEX_STATUS_SUCCESSFUL;
}
static rtems_status_code _Semaphore_Set_priority(
Semaphore_Control *the_semaphore,
const Scheduler_Control *scheduler,
rtems_task_priority new_priority,
rtems_task_priority *old_priority_p,
Thread_queue_Context *queue_context
)
{
rtems_status_code sc;
bool valid;
Priority_Control core_priority;
Priority_Control old_priority;
core_priority = _RTEMS_Priority_To_core( scheduler, new_priority, &valid );
if ( new_priority != RTEMS_CURRENT_PRIORITY && !valid ) {
return RTEMS_INVALID_PRIORITY;
}
_Thread_queue_Acquire_critical(
&the_semaphore->Core_control.Wait_queue,
&queue_context->Lock_context
);
switch ( the_semaphore->variant ) {
case SEMAPHORE_VARIANT_MUTEX_PRIORITY_CEILING:
sc = _Semaphore_Is_scheduler_valid(
&the_semaphore->Core_control.Mutex,
scheduler
);
old_priority = _CORE_ceiling_mutex_Get_priority(
&the_semaphore->Core_control.Mutex
);
if ( sc == RTEMS_SUCCESSFUL && new_priority != RTEMS_CURRENT_PRIORITY ) {
_CORE_ceiling_mutex_Set_priority(
&the_semaphore->Core_control.Mutex,
core_priority
);
}
break;
#if defined(RTEMS_SMP)
case SEMAPHORE_VARIANT_MRSP:
old_priority = _MRSP_Get_priority(
&the_semaphore->Core_control.MRSP,
scheduler
);
if ( new_priority != RTEMS_CURRENT_PRIORITY ) {
_MRSP_Set_priority(
&the_semaphore->Core_control.MRSP,
scheduler,
core_priority
);
}
sc = RTEMS_SUCCESSFUL;
break;
#endif
default:
_Assert(
the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_INHERIT_PRIORITY
|| the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_NO_PROTOCOL
|| the_semaphore->variant == SEMAPHORE_VARIANT_SIMPLE_BINARY
|| the_semaphore->variant == SEMAPHORE_VARIANT_COUNTING
);
old_priority = 0;
sc = RTEMS_NOT_DEFINED;
break;
}
_Thread_queue_Release(
&the_semaphore->Core_control.Wait_queue,
&queue_context->Lock_context
);
*old_priority_p = _RTEMS_Priority_From_core( scheduler, old_priority );
return sc;
}
rtems_status_code rtems_semaphore_delete(
rtems_id id
)
{
Semaphore_Control *the_semaphore;
Thread_queue_Context queue_context;
Status_Control status;
_Objects_Allocator_lock();
the_semaphore = _Semaphore_Get( id, &queue_context );
if ( the_semaphore == NULL ) {
_Objects_Allocator_unlock();
#if defined(RTEMS_MULTIPROCESSING)
if ( _Semaphore_MP_Is_remote( id ) ) {
return RTEMS_ILLEGAL_ON_REMOTE_OBJECT;
}
#endif
return RTEMS_INVALID_ID;
}
_Thread_queue_Acquire_critical(
&the_semaphore->Core_control.Wait_queue,
&queue_context.Lock_context
);
switch ( the_semaphore->variant ) {
case SEMAPHORE_VARIANT_MUTEX_INHERIT_PRIORITY:
case SEMAPHORE_VARIANT_MUTEX_PRIORITY_CEILING:
case SEMAPHORE_VARIANT_MUTEX_NO_PROTOCOL:
if (
_CORE_mutex_Is_locked(
&the_semaphore->Core_control.Mutex.Recursive.Mutex
)
) {
status = STATUS_RESOURCE_IN_USE;
} else {
status = STATUS_SUCCESSFUL;
}
break;
#if defined(RTEMS_SMP)
case SEMAPHORE_VARIANT_MRSP:
status = _MRSP_Can_destroy( &the_semaphore->Core_control.MRSP );
break;
#endif
default:
_Assert(
the_semaphore->variant == SEMAPHORE_VARIANT_SIMPLE_BINARY
|| the_semaphore->variant == SEMAPHORE_VARIANT_COUNTING
);
status = STATUS_SUCCESSFUL;
break;
}
if ( status != STATUS_SUCCESSFUL ) {
_Thread_queue_Release(
&the_semaphore->Core_control.Wait_queue,
&queue_context.Lock_context
);
_Objects_Allocator_unlock();
return _Status_Get( status );
}
_Objects_Close( &_Semaphore_Information, &the_semaphore->Object );
switch ( the_semaphore->variant ) {
#if defined(RTEMS_SMP)
case SEMAPHORE_VARIANT_MRSP:
_MRSP_Destroy( &the_semaphore->Core_control.MRSP, &queue_context );
break;
#endif
default:
_Assert(
the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_INHERIT_PRIORITY
|| the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_PRIORITY_CEILING
|| the_semaphore->variant == SEMAPHORE_VARIANT_MUTEX_NO_PROTOCOL
|| the_semaphore->variant == SEMAPHORE_VARIANT_SIMPLE_BINARY
|| the_semaphore->variant == SEMAPHORE_VARIANT_COUNTING
);
_Thread_queue_Flush_critical(
&the_semaphore->Core_control.Wait_queue.Queue,
_Semaphore_Get_operations( the_semaphore ),
_Thread_queue_Flush_status_object_was_deleted,
&queue_context
);
_Thread_queue_Destroy( &the_semaphore->Core_control.Wait_queue );
break;
}
#if defined(RTEMS_MULTIPROCESSING)
if ( the_semaphore->is_global ) {
_Objects_MP_Close( &_Semaphore_Information, id );
_Semaphore_MP_Send_process_packet(
SEMAPHORE_MP_ANNOUNCE_DELETE,
id,
0, /* Not used */
0 /* Not used */
);
}
#endif
_Semaphore_Free( the_semaphore );
_Objects_Allocator_unlock();
return RTEMS_SUCCESSFUL;
}
