containerd-shim-kata-v2: add the service Stats support

Add the Stats api support to get the container's
resouces statistic.

Signed-off-by: ZeroMagic <[email protected]>

containerd-shim-v2/metrics.go

@@ -0,0 +1,66 @@
+// Copyright (c) 2018 HyperHQ Inc.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package containerdshim
+
+import (
+	"github.com/containerd/cgroups"
+	"github.com/containerd/typeurl"
+
+	google_protobuf "github.com/gogo/protobuf/types"
+)
+
+func marshalMetrics(s *service, containerID string) (*google_protobuf.Any, error) {
+	stats, err := s.sandbox.StatsContainer(containerID)
+	if err != nil {
+		return nil, err
+	}
+
+	cgStats := stats.CgroupStats
+
+	var hugetlb []*cgroups.HugetlbStat
+	for _, v := range cgStats.HugetlbStats {
+		hugetlb = append(
+			hugetlb,
+			&cgroups.HugetlbStat{
+				Usage:   v.Usage,
+				Max:     v.MaxUsage,
+				Failcnt: v.Failcnt,
+			})
+	}
+
+	var perCPU []uint64
+	for _, v := range cgStats.CPUStats.CPUUsage.PercpuUsage {
+		perCPU = append(perCPU, v)
+	}
+
+	metrics := &cgroups.Metrics{
+		Hugetlb: hugetlb,
+		Pids: &cgroups.PidsStat{
+			Current: cgStats.PidsStats.Current,
+			Limit:   cgStats.PidsStats.Limit,
+		},
+		CPU: &cgroups.CPUStat{
+			Usage: &cgroups.CPUUsage{
+				Total:  cgStats.CPUStats.CPUUsage.TotalUsage,
+				PerCPU: perCPU,
+			},
+		},
+		Memory: &cgroups.MemoryStat{
+			Cache: cgStats.MemoryStats.Cache,
+			Usage: &cgroups.MemoryEntry{
+				Limit: cgStats.MemoryStats.Usage.Limit,
+				Usage: cgStats.MemoryStats.Usage.Usage,
+			},
+		},
+	}
+
+	data, err := typeurl.MarshalAny(metrics)
+	if err != nil {
+		return nil, err
+	}
+
+	return data, nil
+}

containerd-shim-v2/service.go

@@ -661,7 +661,22 @@ func (s *service) Shutdown(ctx context.Context, r *taskAPI.ShutdownRequest) (*pt
 }
 
 func (s *service) Stats(ctx context.Context, r *taskAPI.StatsRequest) (*taskAPI.StatsResponse, error) {
-	return nil, errdefs.ErrNotImplemented
+	s.Lock()
+	defer s.Unlock()
+
+	c, err := s.getContainer(r.ID)
+	if err != nil {
+		return nil, err
+	}
+
+	data, err := marshalMetrics(s, c.id)
+	if err != nil {
+		return nil, err
+	}
+
+	return &taskAPI.StatsResponse{
+		Stats: data,
+	}, nil
 }
 
 // Update a running container