2.6.0 schedule_tick question

[Der Herr Hofrat]

HI !

 in 2.6.0 kernel/sched.c scheduler_tick currently the 
 case of rt_tasks for SCHED_RR is doing

	if ((p->policy == SCHED_RR) && !--p->time_slice) {
			...
                        dequeue_task(p, rq->active);
                        enqueue_task(p, rq->active);

 which is:

static inline void dequeue_task(struct task_struct *p, prio_array_t *array)
{
        array->nr_active--;
        list_del(&p->run_list);
        if (list_empty(array->queue + p->prio))
                __clear_bit(p->prio, array->bitmap);
}

static inline void enqueue_task(struct task_struct *p, prio_array_t *array)
{
        list_add_tail(&p->run_list, array->queue + p->prio);
        __set_bit(p->prio, array->bitmap);
        array->nr_active++;
        p->array = array;
}

 looking at these two functions this looks like quite some overhead as it
 actually could be reduced to:

        list_del(&p->run_list);
	list_add_tail(&p->run_list, array->queue + p->prio);

 for the rest I don't see any effect it would have ?

hofrat
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