basecginfo is:
11:hugetlb:/
10:perf_event:/
9:blkio:/init.scope
8:devices:/init.scope
7:pids:/init.scope
6:memory:/init.scope
5:cpuset:/
4:freezer:/
3:cpu,cpuacct:/init.scope
2:net_cls,net_prio:/
1:name=systemd:/init.scope
0::/init.scope

kernel subsystem 0: hugetlb
kernel subsystem 1: perf_event
kernel subsystem 2: blkio
kernel subsystem 3: devices
kernel subsystem 4: pids
kernel subsystem 5: memory
kernel subsystem 6: cpuset
kernel subsystem 7: freezer
kernel subsystem 8: cpu
kernel subsystem 9: cpuacct
kernel subsystem 10: net_cls
kernel subsystem 11: net_prio
kernel subsystem 12: cgroup2
named subsystem 0: name=systemd
writeable subsystems:
  Hierarchies:
  0: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/unified
      controllers:
      0: cgroup2
  1: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/systemd
      controllers:
      0: name=systemd
  2: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/net_cls,net_prio
      controllers:
      0: net_cls
      1: net_prio
  3: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/cpu,cpuacct
      controllers:
      0: cpu
      1: cpuacct
  4: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/freezer
      controllers:
      0: freezer
  5: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/cpuset
      controllers:
      0: cpuset
  6: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/memory
      controllers:
      0: memory
  7: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/pids
      controllers:
      0: pids
  8: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/devices
      controllers:
      0: devices
  9: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/blkio
      controllers:
      0: blkio
  10: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/perf_event
      controllers:
      0: perf_event
  11: base_cgroup: /
      mountpoint:  /sys/fs/cgroup/hugetlb
      controllers:
      0: hugetlb
rootu1