$ systemd-cgls --help
systemd-cgls [OPTIONS...] [CGROUP...]
Recursively show control group contents.
-h --help Show this help
--version Show package version
--no-pager Do not pipe output into a pager
-a --all Show all groups, including empty
-u --unit Show the subtrees of specified system units
--user-unit Show the subtrees of specified user units
-x --xattr=BOOL Show cgroup extended attributes
-c --cgroup-id=BOOL Show cgroup ID
-l --full Do not ellipsize output
-k Include kernel threads in output
-M --machine=NAME Show container NAME
See the systemd-cgls(1) man page for details.