static int __maybe_unused cgroup_extra_stat_show(struct seq_file *seq,
						 struct cgroup *cgrp, int ssid)
{
	struct cgroup_subsys *ss = cgroup_subsys[ssid];
	struct cgroup_subsys_state *css;
	int ret;

	if (!ss->css_extra_stat_show)
		return 0;

	css = cgroup_tryget_css(cgrp, ss);
	if (!css)
		return 0;

	ret = ss->css_extra_stat_show(seq, css);
	css_put(css);
	return ret;
}
static int __maybe_unused cgroup_extra_stat_show(struct seq_file *seq,
						 struct cgroup *cgrp, int ssid)
{
	struct cgroup_subsys *ss = cgroup_subsys[ssid];
	struct cgroup_subsys_state *css;
	int ret;

	if (!ss->css_extra_stat_show)
		return 0;

	css = cgroup_tryget_css(cgrp, ss);
	if (!css)
		return 0;

	ret = ss->css_extra_stat_show(seq, css);
	css_put(css);
	return ret;
}