static int add_module_usage(struct module *a, struct module *b)
{
	struct module_use *use;

	pr_debug("Allocating new usage for %s.\n", a->name);
	use = kmalloc(sizeof(*use), GFP_ATOMIC);
	if (!use)
		return -ENOMEM;

	use->source = a;
	use->target = b;
	list_add(&use->source_list, &b->source_list);
	list_add(&use->target_list, &a->target_list);
	return 0;
}
static int add_module_usage(struct module *a, struct module *b)
{
	struct module_use *use;

	pr_debug("Allocating new usage for %s.\n", a->name);
	use = kmalloc(sizeof(*use), GFP_ATOMIC);
	if (!use)
		return -ENOMEM;

	use->source = a;
	use->target = b;
	list_add(&use->source_list, &b->source_list);
	list_add(&use->target_list, &a->target_list);
	return 0;
}