kubernetes/vendor/github.com/opencontainers/runc/libcontainer/cgroups/manager/new.go

// New returns the instance of a cgroup manager, which is chosen
// based on the local environment (whether cgroup v1 or v2 is used)
// and the config (whether config.Systemd is set or not).
func New(config *configs.Cgroup) (cgroups.Manager, error) { … }

// NewWithPaths is similar to New, and can be used in case cgroup paths
// are already well known, which can save some resources.
//
// For cgroup v1, the keys are controller/subsystem name, and the values
// are absolute filesystem paths to the appropriate cgroups.
//
// For cgroup v2, the only key allowed is "" (empty string), and the value
// is the unified cgroup path.
func NewWithPaths(config *configs.Cgroup, paths map[string]string) (cgroups.Manager, error) { … }

// getUnifiedPath is an implementation detail of libcontainer.
// Historically, libcontainer.Create saves cgroup paths as per-subsystem path
// map (as returned by cm.GetPaths(""), but with v2 we only have one single
// unified path (with "" as a key).
//
// This function converts from that map to string (using "" as a key),
// and also checks that the map itself is sane.
func getUnifiedPath(paths map[string]string) (string, error) { … }