topology.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Scheduler topology setup/handling methods
 */
#include "sched.h"

DEFINE_MUTEX(sched_domains_mutex);

/* Protected by sched_domains_mutex: */
static cpumask_var_t sched_domains_tmpmask;
static cpumask_var_t sched_domains_tmpmask2;

#ifdef CONFIG_SCHED_DEBUG

static int __init sched_debug_setup(char *str)
{
	sched_debug_enabled = true;

	return 0;
}
early_param("sched_debug", sched_debug_setup);

static inline bool sched_debug(void)
{
	return sched_debug_enabled;
}

static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
				  struct cpumask *groupmask)
{
	struct sched_group *group = sd->groups;

	cpumask_clear(groupmask);

	printk(KERN_DEBUG "%*s domain-%d: ", level, "", level);

	if (!(sd->flags & SD_LOAD_BALANCE)) {
		printk("does not load-balance\n");
		if (sd->parent)
			printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain has parent");
		return -1;
	}

	printk(KERN_CONT "span=%*pbl level=%s\n",
	       cpumask_pr_args(sched_domain_span(sd)), sd->name);

	if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) {
		printk(KERN_ERR "ERROR: domain->span does not contain CPU%d\n", cpu);
	}
	if (group && !cpumask_test_cpu(cpu, sched_group_span(group))) {
		printk(KERN_ERR "ERROR: domain->groups does not contain CPU%d\n", cpu);
	}

	printk(KERN_DEBUG "%*s groups:", level + 1, "");
	do {
		if (!group) {
			printk("\n");
			printk(KERN_ERR "ERROR: group is NULL\n");
			break;
		}

		if (!cpumask_weight(sched_group_span(group))) {
			printk(KERN_CONT "\n");
			printk(KERN_ERR "ERROR: empty group\n");
			break;
		}

		if (!(sd->flags & SD_OVERLAP) &&
		    cpumask_intersects(groupmask, sched_group_span(group))) {
			printk(KERN_CONT "\n");