static int sched_dl_global_validate(void)
{
	u64 runtime = global_rt_runtime();
	u64 period = global_rt_period();
	u64 new_bw = to_ratio(period, runtime);
	struct dl_bw *dl_b;
	int cpu, ret = 0;
	unsigned long flags;

	/*
	 * Here we want to check the bandwidth not being set to some
	 * value smaller than the currently allocated bandwidth in
	 * any of the root_domains.
	 *
	 * FIXME: Cycling on all the CPUs is overdoing, but simpler than
	 * cycling on root_domains... Discussion on different/better
	 * solutions is welcome!
	 */
	for_each_possible_cpu(cpu) {
		rcu_read_lock_sched();
		dl_b = dl_bw_of(cpu);

		raw_spin_lock_irqsave(&dl_b->lock, flags);
		if (new_bw < dl_b->total_bw)
			ret = -EBUSY;
		raw_spin_unlock_irqrestore(&dl_b->lock, flags);

		rcu_read_unlock_sched();

		if (ret)
			break;
	}

	return ret;
}
Unknown