[root@localhost ~]# mkdir /mnt/cgroup2
[root@localhost ~]# mount -t cgroup2 cgroup2 /mnt/cgroup2/

[root@localhost ~]# umount /sys/fs/cgroup/cpu
[root@localhost ~]# cat /mnt/cgroup2/cgroup.controllers
cpu
[root@localhost ~]# cat /mnt/cgroup2/cgroup.subtree_control
（输出为空）
[root@localhost ~]# echo "+cpu" > /mnt/cgroup2/cgroup.subtree_control
-bash: echo: write error: Invalid argument