/*
* === FUNCTION ======================================================================
* Name: OS_SemPost
* Description: This functions release the semaphore and wakes up the task
* being blocked on it. A task can be also be waiting for a time event, so this
* function vefiries whether the relased task is also waiting for a time event
* or not. In case it is, the task is also removed from the time queue.
* =====================================================================================
*/
int OS_SemPost(OS_SemID_t _sem)
{
OS_task_t *task;
OS_Node_t *n;
OS_SemID_t id_sem = _sem;
KTRACE_EVENT_SEM(KEVENT_UNLOCK, SEM(id_sem)->sem_id);
if(OS_ListGetNum(&(SEM(id_sem)->list)) != 0)
{
/* Outs the task from the semaphore queue */
n = OS_ListGetNode(&(SEM(id_sem)->list));
task = GET_ELEMENT(OS_task_t, n, resource_node);
/* Store what is the blocked thread in the semaphore structure */
SEM(id_sem)->tid_in = task->tid;
KTRACE_EVENT_SEM_TID(KEVENT_LOCK_CATCHED, SEM(id_sem)->sem_id, task->tid);
/*
* Verifies if the thread is blocked in the time queue
* due to a TimedWait system call
*/
if(task->status | TS_TIME_BLOCKED) {
OS_TimeRemoveFromQueue(task);
}
/* Reset the wait_sem value */
task->wait_sem = 0;
/* Add the blocked task to the ready task queue */
OS_SchedTaskReady(task->tid);
}
else {
/* Increment the semaphore counter */
SEM(id_sem)->sem_value = 1;
OS_ListReset(&(SEM(id_sem)->list));
}
return 0;
}
/*
* Function: tid_t OS_TaskCreate(uint32_t _stack_size, void *_ip, uint8 _priority)
*
* This routine creates a new thread and returns the TCB created
*/
tid_t OS_TaskCreate(uint32_t *_stackaddr, uint32_t _stacksize, void *_ip, void *_arg, uint8_t _priority)
{
OS_task_t *task;
OS_Node_t *n;
// DEBUG ("(_stackaddr=%p, _stacksize=%p, _ip=%p, _arg=%p, priority=%d)",
// _stackaddr, _stacksize, _ip, _arg, _priority);
ASSERT (_priority <= SCHED_MIN_PRIORITY);
/* get a free thread control block */
n = (OS_Node_t *) OS_ListGetNode (&tcb_list);
/* assert that we really have a free tcb */
ASSERT (n != NULL);
if (n == NULL) return -1;
task = GET_ELEMENT(OS_task_t, n, node);
TRACE (task->tid, "d");
KTRACE (KTRACE_CREATE, task->tid, _priority);
/* Stablish the thread stack */
if (_stackaddr == NULL)
{
if (_stacksize < CONFIG_ERCOS_MIN_STACK) _stacksize = CONFIG_ERCOS_MIN_STACK;
_stackaddr = OS_Malloc (_stacksize);
} else {
ASSERT (_stacksize >= CONFIG_ERCOS_MIN_STACK);
}
task->stack.size = _stacksize;
task->stack.addr = (uint8_t *)_stackaddr;
/* Fill the stack with the 0x5a mark */
#ifndef CONFIG_NDEBUG
// unsigned i;
// DEBUG ("Stack @ %p, %p bytes", _stackaddr, _stacksize);
// for (i = 0; i < _stacksize; i++) ((uint8_t *) _stackaddr)[i] = 0x5a;
#endif
/* Init the new thread context */
ercos_hal_hwcontext_init (&(task->context), task->stack.addr, task->stack.size, 0, OS_ThreadWrapper);
/* Stablish the thread status */
task->status = TS_READY;
/* Stablish the thread entry point */
task->entry_point = _ip;
task->arg = _arg;
/* Init the pointer to the catched mutex */
task->pmutex =(OS_Mutex_t*) NULL;
/* Set the thread base and temporal priorities */
task->priority = _priority;
task->base_priority = _priority;
/* Add the task to the correspond sched queue */
OS_SchedTaskReady(task->tid);
return task->tid;
}
