static int __acpi_processor_set_throttling()

in processor_throttling.c [48:188]

• 90 lines of code
• 18 McCabe index (conditional complexity)

static int __acpi_processor_set_throttling(struct acpi_processor *pr,
					   int state, bool force, bool direct);

static int acpi_processor_update_tsd_coord(void)
{
	int count, count_target;
	int retval = 0;
	unsigned int i, j;
	cpumask_var_t covered_cpus;
	struct acpi_processor *pr, *match_pr;
	struct acpi_tsd_package *pdomain, *match_pdomain;
	struct acpi_processor_throttling *pthrottling, *match_pthrottling;

	if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
		return -ENOMEM;

	/*
	 * Now that we have _TSD data from all CPUs, lets setup T-state
	 * coordination between all CPUs.
	 */
	for_each_possible_cpu(i) {
		pr = per_cpu(processors, i);
		if (!pr)
			continue;

		/* Basic validity check for domain info */
		pthrottling = &(pr->throttling);

		/*
		 * If tsd package for one cpu is invalid, the coordination
		 * among all CPUs is thought as invalid.
		 * Maybe it is ugly.
		 */
		if (!pthrottling->tsd_valid_flag) {
			retval = -EINVAL;
			break;
		}
	}
	if (retval)
		goto err_ret;

	for_each_possible_cpu(i) {
		pr = per_cpu(processors, i);
		if (!pr)
			continue;

		if (cpumask_test_cpu(i, covered_cpus))
			continue;
		pthrottling = &pr->throttling;

		pdomain = &(pthrottling->domain_info);
		cpumask_set_cpu(i, pthrottling->shared_cpu_map);
		cpumask_set_cpu(i, covered_cpus);
		/*
		 * If the number of processor in the TSD domain is 1, it is
		 * unnecessary to parse the coordination for this CPU.
		 */
		if (pdomain->num_processors <= 1)
			continue;

		/* Validate the Domain info */
		count_target = pdomain->num_processors;
		count = 1;

		for_each_possible_cpu(j) {
			if (i == j)
				continue;

			match_pr = per_cpu(processors, j);
			if (!match_pr)
				continue;

			match_pthrottling = &(match_pr->throttling);
			match_pdomain = &(match_pthrottling->domain_info);
			if (match_pdomain->domain != pdomain->domain)
				continue;

			/* Here i and j are in the same domain.
			 * If two TSD packages have the same domain, they
			 * should have the same num_porcessors and
			 * coordination type. Otherwise it will be regarded
			 * as illegal.
			 */
			if (match_pdomain->num_processors != count_target) {
				retval = -EINVAL;
				goto err_ret;
			}

			if (pdomain->coord_type != match_pdomain->coord_type) {
				retval = -EINVAL;
				goto err_ret;
			}

			cpumask_set_cpu(j, covered_cpus);
			cpumask_set_cpu(j, pthrottling->shared_cpu_map);
			count++;
		}
		for_each_possible_cpu(j) {
			if (i == j)
				continue;

			match_pr = per_cpu(processors, j);
			if (!match_pr)
				continue;

			match_pthrottling = &(match_pr->throttling);
			match_pdomain = &(match_pthrottling->domain_info);
			if (match_pdomain->domain != pdomain->domain)
				continue;

			/*
			 * If some CPUS have the same domain, they
			 * will have the same shared_cpu_map.
			 */
			cpumask_copy(match_pthrottling->shared_cpu_map,
				     pthrottling->shared_cpu_map);
		}
	}

err_ret:
	free_cpumask_var(covered_cpus);

	for_each_possible_cpu(i) {
		pr = per_cpu(processors, i);
		if (!pr)
			continue;

		/*
		 * Assume no coordination on any error parsing domain info.
		 * The coordination type will be forced as SW_ALL.
		 */
		if (retval) {
			pthrottling = &(pr->throttling);
			cpumask_clear(pthrottling->shared_cpu_map);
			cpumask_set_cpu(i, pthrottling->shared_cpu_map);
			pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
		}
	}

	return retval;
}