Merge pull request #352 from alekdu/improve_vpu_coverage

vpu: improve test coverage

cmd/vpu_plugin/vpu_plugin.go

@@ -39,6 +39,8 @@ const (
 	hddlServicePath1 = "/var/tmp/hddl_service_ready.mutex"
 	hddlServicePath2 = "/var/tmp/hddl_service_alive.mutex"
 	ionDevNode       = "/dev/ion"
+	// Frequency of device scans
+	scanFrequency = 5 * time.Second
 )
 
 var (
@@ -55,18 +57,27 @@ type devicePlugin struct {
 	vendorID     int
 	productIDs   []int
 	sharedDevNum int
+	scanTicker   *time.Ticker
+	scanDone     chan bool
 }
 
 func newDevicePlugin(usbContext gousbContext, vendorID int, productIDs []int, sharedDevNum int) *devicePlugin {
+	if sharedDevNum < 1 {
+		klog.V(1).Info("The number of containers sharing the same VPU must greater than zero")
+		return nil
+	}
 	return &devicePlugin{
 		usbContext:   usbContext,
 		vendorID:     vendorID,
 		productIDs:   productIDs,
 		sharedDevNum: sharedDevNum,
+		scanTicker:   time.NewTicker(scanFrequency),
+		scanDone:     make(chan bool, 1),
 	}
 }
 
 func (dp *devicePlugin) Scan(notifier dpapi.Notifier) error {
+	defer dp.scanTicker.Stop()
 	for {
 		devTree, err := dp.scan()
 		if err != nil {
@@ -75,7 +86,11 @@ func (dp *devicePlugin) Scan(notifier dpapi.Notifier) error {
 
 		notifier.Notify(devTree)
 
-		time.Sleep(5 * time.Second)
+		select {
+		case <-dp.scanDone:
+			return nil
+		case <-dp.scanTicker.C:
+		}
 	}
 }
 
@@ -156,16 +171,8 @@ func main() {
 	var sharedDevNum int
 
 	flag.IntVar(&sharedDevNum, "shared-dev-num", 1, "number of containers sharing the same VPU device")
-
 	flag.Parse()
 
-	klog.V(4).Info("debug is on")
-
-	if sharedDevNum < 1 {
-		klog.Fatal("The number of containers sharing the same VPU must greater than zero")
-		os.Exit(1)
-	}
-
 	klog.V(1).Info("VPU device plugin started")
 
 	// add lsusb here
@@ -179,6 +186,9 @@ func main() {
 	}
 
 	plugin := newDevicePlugin(ctx, vendorID, productIDs, sharedDevNum)
+	if plugin == nil {
+		klog.Fatal("Cannot create device plugin, please check above error messages.")
+	}
 	manager := dpapi.NewManager(namespace, plugin)
 	manager.Run()
 }

cmd/vpu_plugin/vpu_plugin_test.go

@@ -20,6 +20,7 @@ import (
 	"testing"
 
 	"github.com/google/gousb"
+	dpapi "github.com/intel/intel-device-plugins-for-kubernetes/pkg/deviceplugin"
 	"k8s.io/klog"
 )
 
@@ -49,9 +50,22 @@ func (t *testCase) OpenDevices(opener func(desc *gousb.DeviceDesc) bool) ([]*gou
 	return ret, nil
 }
 
+// fakeNotifier implements Notifier interface.
+type fakeNotifier struct {
+	scanDone chan bool
+	tree     dpapi.DeviceTree
+}
+
+// Notify stops plugin Scan
+func (n *fakeNotifier) Notify(newDeviceTree dpapi.DeviceTree) {
+	n.tree = newDeviceTree
+	n.scanDone <- true
+}
+
 func TestScan(t *testing.T) {
+	var fN fakeNotifier
+
 	f, err := os.Create("/var/tmp/hddl_service.sock")
-	defer f.Close()
 	if err != nil {
 		t.Error("create fake hddl file failed")
 	}
@@ -64,13 +78,40 @@ func TestScan(t *testing.T) {
 	testPlugin := newDevicePlugin(tc, vendorID, productIDs, 10)
 
 	if testPlugin == nil {
-		t.Error("vpu plugin test failed")
+		t.Error("vpu plugin test failed with newDevicePlugin().")
 	}
 
-	tree, err := testPlugin.scan()
+	fN.scanDone = testPlugin.scanDone
+	err = testPlugin.Scan(&fN)
 	if err != nil {
-		t.Error("vpu plugin test failed")
-	} else {
-		klog.V(4).Infof("tree len is %d", len(tree[deviceType]))
+		t.Error("vpu plugin test failed with testPlugin.Scan()")
+	}
+	if len(fN.tree[deviceType]) == 0 {
+		t.Error("vpu plugin test failed with testPlugin.Scan(): tree len is 0")
+	}
+	klog.V(4).Infof("tree len is %d", len(fN.tree[deviceType]))
+
+	//remove the hddl_service.sock and test with no hddl socket case
+	f.Close()
+	os.Remove("/var/tmp/hddl_service.sock")
+	testPlugin = newDevicePlugin(tc, vendorID, productIDs, 10)
+
+	if testPlugin == nil {
+		t.Error("vpu plugin test failed with newDevicePlugin() in no hddl_service.sock case.")
+	}
+
+	fN.scanDone = testPlugin.scanDone
+	err = testPlugin.Scan(&fN)
+	if err != nil {
+		t.Error("vpu plugin test failed with testPlugin.Scan() in no hddl_service.sock case.")
+	}
+	if len(fN.tree[deviceType]) != 0 {
+		t.Error("vpu plugin test failed with testPlugin.Scan(): tree len should be 0 in no hddl_service.sock case.")
+	}
+
+	//test with sharedNum equals 0 case
+	testPlugin = newDevicePlugin(tc, vendorID, productIDs, 0)
+	if testPlugin != nil {
+		t.Error("vpu plugin test fail: newDevicePlugin should fail with 0 sharedDevNum")
 	}
 }