Re: [PATCH v7 11/14] mpam,x86/resctrl: Resolve INTEL_PMT_TELEMETRY symbols at runtime

[Luck, Tony]

With renamed variable, and comment. Is this clearer?


/*
 * intel_aet_register_enumeration() provides the value of "THIS_MODULE"
 * from the the pmt_telemetry module. Note that this is NULL when
 * CONFIG_INTEL_PMT_TELEMETRY=y so it serves as a flag to decide whether
 * try_module_get() and module_put() need to be called.
 */
static struct module *pmt_is_a_module;

...


/*
 * Track whether pmt_telemetry enumeration succeeded during mount for use
 * during unmount.
 */
static bool pmt_in_use;

bool intel_aet_pre_mount(void)
{
	bool ret;

	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
		return false;

	guard(mutex)(&aet_register_lock);
	if (!get_feature || !put_feature)
		return false;

	if (pmt_is_a_module) {
		if (!try_module_get(pmt_is_a_module))
			return false;
	}

	ret = aet_get_events();

	if (!ret) {
		if (pmt_is_a_module)
			module_put(pmt_is_a_module);
	} else {
		pmt_in_use = true;
	}

	return ret;
}

void intel_aet_unmount(void)
{
	struct event_group **peg;

	guard(mutex)(&aet_register_lock);
	if (!pmt_in_use)
		return;

	for_each_event_group(peg) {
		if ((*peg)->pfg) {
			struct event_group *e = *peg;

			for (int j = 0; j < e->num_events; j++)
				resctrl_disable_mon_event(e->evts[j].id);
			put_feature((*peg)->pfg);
			(*peg)->pfg = NULL;
		}
	}
	if (pmt_is_a_module)
		module_put(pmt_is_a_module);
	pmt_in_use = false;
}


-Tony