cgroups: Make systemd cgroup parent support to use specified slices.

Signed-off-by: Mrunal Patel <[email protected]>

cgroups/systemd/apply_systemd.go

@@ -147,8 +147,8 @@ func (m *Manager) Apply(pid int) error {
 		properties []systemd.Property
 	)
 
-	if c.Slice != "" {
-		slice = c.Slice
+	if c.Parent != "" {
+		slice = c.Parent
 	}
 
 	properties = append(properties,
@@ -312,8 +312,8 @@ func getSubsystemPath(c *configs.Cgroup, subsystem string) (string, error) {
 	}
 
 	slice := "system.slice"
-	if c.Slice != "" {
-		slice = c.Slice
+	if c.Parent != "" {
+		slice = c.Parent
 	}
 
 	return filepath.Join(mountpoint, initPath, slice, getUnitName(c)), nil
@@ -377,7 +377,7 @@ func (m *Manager) Set(container *configs.Config) error {
 }
 
 func getUnitName(c *configs.Cgroup) string {
-	return fmt.Sprintf("%s-%s.scope", c.Parent, c.Name)
+	return fmt.Sprintf("%s-%s.scope", c.ScopePrefix, c.Name)
 }
 
 // Atm we can't use the systemd device support because of two missing things:

configs/cgroup.go

@@ -52,8 +52,8 @@ type Cgroup struct {
 	// set the freeze value for the process
 	Freezer FreezerState `json:"freezer"`
 
-	// Parent slice to use for systemd TODO: remove in favor or parent
-	Slice string `json:"slice"`
+	// prefix for the scope name
+	ScopePrefix string `json:"scope_prefix"`
 
 	// Whether to disable OOM Killer
 	OomKillDisable bool `json:"oom_kill_disable"`

nsinit/config.go

@@ -28,6 +28,7 @@ var createFlags = []cli.Flag{
 	cli.IntFlag{Name: "memory-swap", Usage: "set the memory swap limit for the container"},
 	cli.StringFlag{Name: "cpuset-cpus", Usage: "set the cpuset cpus"},
 	cli.StringFlag{Name: "cpuset-mems", Usage: "set the cpuset mems"},
+	cli.StringFlag{Name: "cgroup-parent", Usage: "set the cgroup parent"},
 	cli.StringFlag{Name: "apparmor-profile", Usage: "set the apparmor profile"},
 	cli.StringFlag{Name: "process-label", Usage: "set the process label"},
 	cli.StringFlag{Name: "mount-label", Usage: "set the mount label"},
@@ -92,6 +93,11 @@ func modify(config *configs.Config, context *cli.Context) {
 		config.Rootfs = rootfs
 	}
 
+	cgroupParent := context.String("cgroup-parent")
+	if cgroupParent != "" {
+		config.Cgroups.Parent = cgroupParent
+	}
+
 	userns_uid := context.Int("userns-root-uid")
 	if userns_uid != 0 {
 		config.Namespaces.Add(configs.NEWUSER, "")
@@ -222,7 +228,7 @@ func getTemplate() *configs.Config {
 		}),
 		Cgroups: &configs.Cgroup{
 			Name:            filepath.Base(cwd),
-			Parent:          "nsinit",
+			ScopePrefix:     "nsinit",
 			AllowAllDevices: false,
 			AllowedDevices:  configs.DefaultAllowedDevices,
 		},