Use cached state instead of runc state.

Signed-off-by: Lantao Liu <lantaol@google.com>

pkg/process/utils.go

@@ -27,6 +27,7 @@ import (
 	"path/filepath"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/containerd/containerd/errdefs"
@@ -62,6 +63,20 @@ func (s *safePid) set(pid int) {
 	s.Unlock()
 }
 
+type atomicBool int32
+
+func (ab *atomicBool) set(b bool) {
+	if b {
+		atomic.StoreInt32((*int32)(ab), 1)
+	} else {
+		atomic.StoreInt32((*int32)(ab), 0)
+	}
+}
+
+func (ab *atomicBool) get() bool {
+	return atomic.LoadInt32((*int32)(ab)) == 1
+}
+
 // TODO(mlaventure): move to runc package?
 func getLastRuntimeError(r *runc.Runc) (string, error) {
 	if r.Log == "" {