static void cgroup_propagate_control(struct cgroup *cgrp)
{
	struct cgroup *dsct;
	struct cgroup_subsys_state *d_css;

	cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp) {
		dsct->subtree_control &= cgroup_control(dsct);
		dsct->subtree_ss_mask =
			cgroup_calc_subtree_ss_mask(dsct->subtree_control,
						    cgroup_ss_mask(dsct));
	}
}
static void cgroup_propagate_control(struct cgroup *cgrp)
{
	struct cgroup *dsct;
	struct cgroup_subsys_state *d_css;

	cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp) {
		dsct->subtree_control &= cgroup_control(dsct);
		dsct->subtree_ss_mask =
			cgroup_calc_subtree_ss_mask(dsct->subtree_control,
						    cgroup_ss_mask(dsct));
	}
}