Simplify synchronization between runsc and sandbox process

Make 'runsc create' join cgroup before creating sandbox process.
This removes the need to synchronize platform creation and ensure
that sandbox process is charged to the right cgroup from the start.

PiperOrigin-RevId: 227166451
Change-Id: Ieb4b18e6ca0daf7b331dc897699ca419bc5ee3a2

1 files changed, 32 insertions, 0 deletions

diff --git a/runsc/test/root/cgroup_test.go b/runsc/test/root/cgroup_test.go
index fdb94ff64..0eabf9561 100644
--- a/runsc/test/root/cgroup_test.go
+++ b/runsc/test/root/cgroup_test.go
@@ -18,6 +18,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"testing"
 
@@ -123,6 +124,8 @@ func TestCgroup(t *testing.T) {
 		t.Fatalf("Docker.ID() failed: %v", err)
 	}
 	t.Logf("cgroup ID: %s", gid)
+
+	// Check list of attributes defined above.
 	for _, attr := range attrs {
 		path := filepath.Join("/sys/fs/cgroup", attr.ctrl, "docker", gid, attr.file)
 		out, err := ioutil.ReadFile(path)
@@ -137,4 +140,33 @@ func TestCgroup(t *testing.T) {
 			t.Errorf("arg: %q, cgroup attribute %s/%s, got: %q, want: %q", attr.arg, attr.ctrl, attr.file, got, attr.want)
 		}
 	}
+
+	// Check that sandbox is inside cgroup.
+	controllers := []string{
+		"blkio",
+		"cpu",
+		"cpuset",
+		"memory",
+		"net_cls",
+		"net_prio",
+		"devices",
+		"freezer",
+		"perf_event",
+		"pids",
+		"systemd",
+	}
+	pid, err := d.SandboxPid()
+	if err != nil {
+		t.Fatalf("SandboxPid: %v", err)
+	}
+	for _, ctrl := range controllers {
+		path := filepath.Join("/sys/fs/cgroup", ctrl, "docker", gid, "cgroup.procs")
+		out, err := ioutil.ReadFile(path)
+		if err != nil {
+			t.Fatalf("failed to read %q: %v", path, err)
+		}
+		if got := string(out); !strings.Contains(got, strconv.Itoa(pid)) {
+			t.Errorf("cgroup control %s processes, got: %q, want: %q", ctrl, got, pid)
+		}
+	}
 }