static int rapl_package_register_powercap()

in intel_rapl_common.c [1153:1223]

• 55 lines of code
• 10 McCabe index (conditional complexity)

static int rapl_package_register_powercap(struct rapl_package *rp)
{
	struct rapl_domain *rd;
	struct powercap_zone *power_zone = NULL;
	int nr_pl, ret;

	/* Update the domain data of the new package */
	rapl_update_domain_data(rp);

	/* first we register package domain as the parent zone */
	for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) {
		if (rd->id == RAPL_DOMAIN_PACKAGE) {
			nr_pl = find_nr_power_limit(rd);
			pr_debug("register package domain %s\n", rp->name);
			power_zone = powercap_register_zone(&rd->power_zone,
					    rp->priv->control_type, rp->name,
					    NULL, &zone_ops[rd->id], nr_pl,
					    &constraint_ops);
			if (IS_ERR(power_zone)) {
				pr_debug("failed to register power zone %s\n",
					 rp->name);
				return PTR_ERR(power_zone);
			}
			/* track parent zone in per package/socket data */
			rp->power_zone = power_zone;
			/* done, only one package domain per socket */
			break;
		}
	}
	if (!power_zone) {
		pr_err("no package domain found, unknown topology!\n");
		return -ENODEV;
	}
	/* now register domains as children of the socket/package */
	for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) {
		struct powercap_zone *parent = rp->power_zone;

		if (rd->id == RAPL_DOMAIN_PACKAGE)
			continue;
		if (rd->id == RAPL_DOMAIN_PLATFORM)
			parent = NULL;
		/* number of power limits per domain varies */
		nr_pl = find_nr_power_limit(rd);
		power_zone = powercap_register_zone(&rd->power_zone,
						    rp->priv->control_type,
						    rd->name, parent,
						    &zone_ops[rd->id], nr_pl,
						    &constraint_ops);

		if (IS_ERR(power_zone)) {
			pr_debug("failed to register power_zone, %s:%s\n",
				 rp->name, rd->name);
			ret = PTR_ERR(power_zone);
			goto err_cleanup;
		}
	}
	return 0;

err_cleanup:
	/*
	 * Clean up previously initialized domains within the package if we
	 * failed after the first domain setup.
	 */
	while (--rd >= rp->domains) {
		pr_debug("unregister %s domain %s\n", rp->name, rd->name);
		powercap_unregister_zone(rp->priv->control_type,
					 &rd->power_zone);
	}

	return ret;
}