static int __init parse_cede_parameters()

in cpuidle-pseries.c [164:212]

• 35 lines of code
• 4 McCabe index (conditional complexity)

static int __init parse_cede_parameters(void)
{
	struct xcede_latency_payload *payload;
	u32 total_xcede_records_size;
	u8 xcede_record_size;
	u16 payload_size;
	int ret, i;

	ret = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1,
			NULL, CEDE_LATENCY_TOKEN, __pa(&xcede_latency_parameter),
			sizeof(xcede_latency_parameter));
	if (ret) {
		pr_err("xcede: Error parsing CEDE_LATENCY_TOKEN\n");
		return ret;
	}

	payload_size = be16_to_cpu(xcede_latency_parameter.payload_size);
	payload = &xcede_latency_parameter.payload;

	xcede_record_size = payload->record_size + 1;

	if (xcede_record_size != sizeof(struct xcede_latency_record)) {
		pr_err("xcede: Expected record-size %lu. Observed size %u.\n",
		       sizeof(struct xcede_latency_record), xcede_record_size);
		return -EINVAL;
	}

	pr_info("xcede: xcede_record_size = %d\n", xcede_record_size);

	/*
	 * Since the payload_size includes the last NULL byte and the
	 * xcede_record_size, the remaining bytes correspond to array of all
	 * cede_latency settings.
	 */
	total_xcede_records_size = payload_size - 2;
	nr_xcede_records = total_xcede_records_size / xcede_record_size;

	for (i = 0; i < nr_xcede_records; i++) {
		struct xcede_latency_record *record = &payload->records[i];
		u64 latency_ticks = be64_to_cpu(record->latency_ticks);
		u8 wake_on_irqs = record->wake_on_irqs;
		u8 hint = record->hint;

		pr_info("xcede: Record %d : hint = %u, latency = 0x%llx tb ticks, Wake-on-irq = %u\n",
			i, hint, latency_ticks, wake_on_irqs);
	}

	return 0;
}