static int push_pxx_to_hypervisor()

in xen-acpi-processor.c [204:267]

• 54 lines of code
• 11 McCabe index (conditional complexity)

static int push_pxx_to_hypervisor(struct acpi_processor *_pr)
{
	int ret = 0;
	struct xen_platform_op op = {
		.cmd			= XENPF_set_processor_pminfo,
		.interface_version	= XENPF_INTERFACE_VERSION,
		.u.set_pminfo.id	= _pr->acpi_id,
		.u.set_pminfo.type	= XEN_PM_PX,
	};
	struct xen_processor_performance *dst_perf;
	struct xen_processor_px *dst_states = NULL;

	dst_perf = &op.u.set_pminfo.perf;

	dst_perf->platform_limit = _pr->performance_platform_limit;
	dst_perf->flags |= XEN_PX_PPC;
	xen_copy_pct_data(&(_pr->performance->control_register),
			  &dst_perf->control_register);
	xen_copy_pct_data(&(_pr->performance->status_register),
			  &dst_perf->status_register);
	dst_perf->flags |= XEN_PX_PCT;
	dst_states = xen_copy_pss_data(_pr, dst_perf);
	if (!IS_ERR_OR_NULL(dst_states)) {
		set_xen_guest_handle(dst_perf->states, dst_states);
		dst_perf->flags |= XEN_PX_PSS;
	}
	if (!xen_copy_psd_data(_pr, dst_perf))
		dst_perf->flags |= XEN_PX_PSD;

	if (dst_perf->flags != (XEN_PX_PSD | XEN_PX_PSS | XEN_PX_PCT | XEN_PX_PPC)) {
		pr_warn("ACPI CPU%u missing some P-state data (%x), skipping\n",
			_pr->acpi_id, dst_perf->flags);
		ret = -ENODEV;
		goto err_free;
	}

	if (!no_hypercall)
		ret = HYPERVISOR_platform_op(&op);

	if (!ret) {
		struct acpi_processor_performance *perf;
		unsigned int i;

		perf = _pr->performance;
		pr_debug("ACPI CPU%u - P-states uploaded.\n", _pr->acpi_id);
		for (i = 0; i < perf->state_count; i++) {
			pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
			(i == perf->state ? '*' : ' '), i,
			(u32) perf->states[i].core_frequency,
			(u32) perf->states[i].power,
			(u32) perf->states[i].transition_latency);
		}
	} else if ((ret != -EINVAL) && (ret != -ENOSYS))
		/* EINVAL means the ACPI ID is incorrect - meaning the ACPI
		 * table is referencing a non-existing CPU - which can happen
		 * with broken ACPI tables. */
		pr_warn("(_PXX): Hypervisor error (%d) for ACPI CPU%u\n",
			ret, _pr->acpi_id);
err_free:
	if (!IS_ERR_OR_NULL(dst_states))
		kfree(dst_states);

	return ret;
}