Exemplo n.º 1
0
/** 
 * Switches the CPU's active thread context to that of the specified thread
 * @param new_thread The thread to switch to
 */
static void SwitchContext(Thread* new_thread) {
    DEBUG_ASSERT_MSG(new_thread->status == THREADSTATUS_READY, "Thread must be ready to become running.");

    Thread* previous_thread = GetCurrentThread();

    // Save context for previous thread
    if (previous_thread) {
        Core::g_app_core->SaveContext(previous_thread->context);

        if (previous_thread->status == THREADSTATUS_RUNNING) {
            // This is only the case when a reschedule is triggered without the current thread
            // yielding execution (i.e. an event triggered, system core time-sliced, etc)
            ready_queue.push_front(previous_thread->current_priority, previous_thread);
            previous_thread->status = THREADSTATUS_READY;
        }
    }

    // Load context of new thread
    if (new_thread) {
        current_thread = new_thread;

        ready_queue.remove(new_thread->current_priority, new_thread);
        new_thread->status = THREADSTATUS_RUNNING;

        Core::g_app_core->LoadContext(new_thread->context);
    } else {
        current_thread = nullptr;
    }
}
Exemplo n.º 2
0
/// Change a thread to "ready" state
void ChangeReadyState(Thread* t, bool ready) {
    Handle handle = t->GetHandle();
    if (t->IsReady()) {
        if (!ready) {
            g_thread_ready_queue.remove(t->current_priority, handle);
        }
    }  else if (ready) {
        if (t->IsRunning()) {
            g_thread_ready_queue.push_front(t->current_priority, handle);
        } else {
            g_thread_ready_queue.push_back(t->current_priority, handle);
        }
        t->status = THREADSTATUS_READY;
    }
}