Refactor task service metrics

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

linux/runcopts/next.pb.txt

@@ -5,17 +5,31 @@ file {
   message_type {
     name: "RuncOptions"
     field {
-      name: "criu_path"
+      name: "runtime"
       number: 1
       label: LABEL_OPTIONAL
       type: TYPE_STRING
+      json_name: "runtime"
+    }
+    field {
+      name: "runtime_root"
+      number: 2
+      label: LABEL_OPTIONAL
+      type: TYPE_STRING
+      json_name: "runtimeRoot"
+    }
+    field {
+      name: "criu_path"
+      number: 3
+      label: LABEL_OPTIONAL
+      type: TYPE_STRING
       json_name: "criuPath"
     }
     field {
       name: "systemd_cgroup"
-      number: 2
+      number: 4
       label: LABEL_OPTIONAL
-      type: TYPE_STRING
+      type: TYPE_BOOL
       json_name: "systemdCgroup"
     }
   }

linux/runtime.go

@@ -245,7 +245,10 @@ func (r *Runtime) Create(ctx context.Context, id string, opts runtime.CreateOpts
 	if err != nil {
 		return nil, errdefs.FromGRPC(err)
 	}
-	t := newTask(id, namespace, int(cr.Pid), s)
+	t, err := newTask(id, namespace, int(cr.Pid), s)
+	if err != nil {
+		return nil, err
+	}
 	if err := r.tasks.Add(ctx, t); err != nil {
 		return nil, err
 	}

linux/task.go

@@ -5,6 +5,7 @@ package linux
 import (
 	"context"
 
+	"github.com/containerd/cgroups"
 	"github.com/containerd/containerd/api/types/task"
 	"github.com/containerd/containerd/errdefs"
 	client "github.com/containerd/containerd/linux/shim"
@@ -18,15 +19,21 @@ type Task struct {
 	pid       int
 	shim      *client.Client
 	namespace string
+	cg        *cgroups.Cgroup
 }
 
-func newTask(id, namespace string, pid int, shim *client.Client) *Task {
+func newTask(id, namespace string, pid int, shim *client.Client) (*Task, error) {
+	cg, err := cgroups.Load(cgroups.V1, cgroups.PidPath(pid))
+	if err != nil {
+		return nil, err
+	}
 	return &Task{
 		id:        id,
 		pid:       pid,
 		shim:      shim,
 		namespace: namespace,
-	}
+		cg:        cg,
+	}, nil
 }
 
 func (t *Task) ID() string {
@@ -201,3 +208,7 @@ func (t *Task) Process(ctx context.Context, id string) (runtime.Process, error)
 		t:  t,
 	}, nil
 }
+
+func (t *Task) Metrics(ctx context.Context) (interface{}, error) {
+	return nil, nil
+}