dl_sched_class 是最终期限调度类:


const struct sched_class dl_sched_class = {
	.next			= &rt_sched_class,
	.enqueue_task		= enqueue_task_dl,
	.dequeue_task		= dequeue_task_dl,
	.yield_task		= yield_task_dl,


	.check_preempt_curr	= check_preempt_curr_dl,


	.pick_next_task		= pick_next_task_dl,
	.put_prev_task		= put_prev_task_dl,


#ifdef CONFIG_SMP
	.select_task_rq		= select_task_rq_dl,
	.set_cpus_allowed       = set_cpus_allowed_dl,
	.rq_online              = rq_online_dl,
	.rq_offline             = rq_offline_dl,
	.task_woken		= task_woken_dl,
#endif


	.set_curr_task		= set_curr_task_dl,
	.task_tick		= task_tick_dl,
	.task_fork              = task_fork_dl,
	.task_dead		= task_dead_dl,


	.prio_changed           = prio_changed_dl,
	.switched_from		= switched_from_dl,
	.switched_to		= switched_to_dl,


	.update_curr		= update_curr_dl,
};