struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
		const struct cpumask *cpu_map, struct sched_domain_attr *attr,
		struct sched_domain *child, int cpu)
{
	struct sched_domain *sd = sd_init(tl, cpu);
	if (!sd)
		return child;

	cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu));
	if (child) {
		sd->level = child->level + 1;
		sched_domain_level_max = max(sched_domain_level_max, sd->level);
		child->parent = sd;
		sd->child = child;

		if (!cpumask_subset(sched_domain_span(child),
				    sched_domain_span(sd))) {
			pr_err("BUG: arch topology borken\n");
#ifdef CONFIG_SCHED_DEBUG
			pr_err("     the %s domain not a subset of the %s domain\n",
					child->name, sd->name);
#endif
			/* Fixup, ensure @sd has at least @child cpus. */
			cpumask_or(sched_domain_span(sd),
				   sched_domain_span(sd),
				   sched_domain_span(child));
		}

	}
	set_domain_attribute(sd, attr);

	return sd;
}
Unknown