libct/cgroups/fs: introduce NewManager()

...and use it from libcontainer/factory_linux.go.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

libcontainer/cgroups/fs/apply_raw.go

@@ -68,6 +68,14 @@ type Manager struct {
 	Paths    map[string]string
 }
 
+func NewManager(cg *configs.Cgroup, paths map[string]string, rootless bool) cgroups.Manager {
+	return &Manager{
+		Cgroups:  cg,
+		Paths:    paths,
+		Rootless: rootless,
+	}
+}
+
 // The absolute path to the root of the cgroup hierarchies.
 var cgroupRootLock sync.Mutex
 var cgroupRoot string

libcontainer/factory_linux.go

@@ -120,20 +120,21 @@ func cgroupfs2(l *LinuxFactory, rootless bool) error {
 	return nil
 }
 
+func cgroupfs(l *LinuxFactory, rootless bool) error {
+	if cgroups.IsCgroup2UnifiedMode() {
+		return cgroupfs2(l, rootless)
+	}
+	l.NewCgroupsManager = func(config *configs.Cgroup, paths map[string]string) cgroups.Manager {
+		return fs.NewManager(config, paths, rootless)
+	}
+	return nil
+}
+
 // Cgroupfs is an options func to configure a LinuxFactory to return containers
 // that use the native cgroups filesystem implementation to create and manage
 // cgroups.
 func Cgroupfs(l *LinuxFactory) error {
-	if cgroups.IsCgroup2UnifiedMode() {
+	return cgroupfs(l, false)
-		return cgroupfs2(l, false)
-	}
-	l.NewCgroupsManager = func(config *configs.Cgroup, paths map[string]string) cgroups.Manager {
-		return &fs.Manager{
-			Cgroups: config,
-			Paths:   paths,
-		}
-	}
-	return nil
 }
 
 // RootlessCgroupfs is an options func to configure a LinuxFactory to return
@@ -143,17 +144,7 @@ func Cgroupfs(l *LinuxFactory) error {
 // during rootless container (including euid=0 in userns) setup (while still allowing cgroup usage if
 // they've been set up properly).
 func RootlessCgroupfs(l *LinuxFactory) error {
-	if cgroups.IsCgroup2UnifiedMode() {
+	return cgroupfs(l, true)
-		return cgroupfs2(l, true)
-	}
-	l.NewCgroupsManager = func(config *configs.Cgroup, paths map[string]string) cgroups.Manager {
-		return &fs.Manager{
-			Cgroups:  config,
-			Rootless: true,
-			Paths:    paths,
-		}
-	}
-	return nil
 }
 
 // IntelRdtfs is an options func to configure a LinuxFactory to return