First commit of smarter-device-manager

main.go

@@ -0,0 +1,190 @@
+// Copyright (c) 2019, ARM
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"regexp"
+	"syscall"
+        "io/ioutil"
+
+	"github.com/fsnotify/fsnotify"
+	"github.com/golang/glog"
+	"gopkg.in/yaml.v2"
+	pluginapi "k8s.io/kubernetes/pkg/kubelet/apis/deviceplugin/v1beta1"
+)
+
+var confFileName string
+
+type DeviceInstance struct {
+	devicePlugin *SmarterDevicePlugin
+
+	deviceName string
+	socketName string
+	deviceFile string
+	numDevices uint
+}
+
+type DesiredDevice struct {
+	DeviceMatch   string
+	NumMaxDevices uint
+}
+
+func usage() {
+	fmt.Fprintf(os.Stderr, "usage: smarter-device-manager\n")
+	flag.PrintDefaults()
+	os.Exit(2)
+}
+
+func init() {
+	flag.Usage = usage
+	// NOTE: This next line is key you have to call flag.Parse() for the command line
+	// options or "flags" that are defined in the glog module to be picked up.
+        flag.StringVar(&confFileName,"config","config/conf.yaml","set the configuration file to use")
+	flag.Parse()
+}
+
+func readDevDirectory() (files []string, err error) {
+	f, err := os.Open("/dev")
+	if err != nil {
+		return nil, err
+	}
+	files, err = f.Readdirnames(-1)
+	f.Close()
+	if err != nil {
+		return nil, err
+	}
+
+	return files, nil
+}
+
+func findDevicesPattern(listDevices []string, pattern string) ([]string,error) {
+	var found []string
+
+	for _, file := range listDevices {
+		res,err := regexp.MatchString(pattern, file)
+                if err != nil {
+                        return nil, err
+                }
+                if res {
+                        found = append(found, file)
+                }
+	}
+	return found,nil
+}
+
+func main() {
+	defer glog.Flush()
+	glog.V(0).Info("Loading smarter-device-manager")
+
+	// Setting up the devices to check
+
+        var desiredDevices []DesiredDevice
+	glog.V(0).Info("Reading configuration file ",confFileName)
+        yamlFile, err := ioutil.ReadFile(confFileName)
+        if err != nil {
+                glog.Fatal("yamlFile.Get err   #%v ", err)
+        }
+        err = yaml.Unmarshal(yamlFile, &desiredDevices)
+        if err != nil {
+                glog.Fatal("Unmarshal: %v", err)
+                os.Exit(-1)
+        }
+
+	glog.V(0).Info("Reading existing devices on /dev")
+	ExistingDevices, err := readDevDirectory()
+	if err != nil {
+		glog.Errorf(err.Error())
+		os.Exit(1)
+	}
+
+	var listDevicesAvailable []DeviceInstance
+
+	for _, deviceToTest := range desiredDevices {
+                glog.V(0).Infof("Checking devices %s on /dev",deviceToTest.DeviceMatch)
+		foundDevices,err := findDevicesPattern(ExistingDevices, deviceToTest.DeviceMatch)
+                if err != nil {
+                        glog.Errorf(err.Error())
+                        os.Exit(1)
+                }
+
+		// If found some create the devices entry
+		if len(foundDevices) > 0 {
+			for _, deviceToCreate := range foundDevices {
+				var newDevice DeviceInstance
+				newDevice.deviceName = "smarter-devices/" + deviceToCreate
+				newDevice.socketName = pluginapi.DevicePluginPath + "smarter-" + deviceToCreate + ".sock"
+				newDevice.deviceFile = "/dev/" + deviceToCreate
+				newDevice.numDevices = deviceToTest.NumMaxDevices
+				listDevicesAvailable = append(listDevicesAvailable, newDevice)
+                                glog.V(0).Infof("Creating device %s socket and %s name for %s",newDevice.deviceName,newDevice.deviceFile,deviceToTest.DeviceMatch)
+			}
+		}
+	}
+
+	glog.V(0).Info("Starting FS watcher.")
+	watcher, err := newFSWatcher(pluginapi.DevicePluginPath)
+	if err != nil {
+		glog.V(0).Info("Failed to created FS watcher.")
+		os.Exit(1)
+	}
+	defer watcher.Close()
+
+	glog.V(0).Info("Starting OS watcher.")
+	sigs := newOSWatcher(syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)
+
+	restart := true
+
+L:
+	for {
+		if restart {
+			for _, devicesInUse := range listDevicesAvailable {
+				if devicesInUse.devicePlugin != nil {
+					devicesInUse.devicePlugin.Stop()
+				}
+			}
+
+			var err error
+			for _, devicesInUse := range listDevicesAvailable {
+				devicesInUse.devicePlugin = NewSmarterDevicePlugin(devicesInUse.numDevices, devicesInUse.deviceFile, devicesInUse.deviceName, devicesInUse.socketName)
+				if err = devicesInUse.devicePlugin.Serve(); err != nil {
+					glog.V(0).Info("Could not contact Kubelet, retrying. Did you enable the device plugin feature gate?")
+					break
+				}
+			}
+			if err != nil {
+				continue
+			}
+
+			restart = false
+		}
+
+		select {
+		case event := <-watcher.Events:
+			if event.Name == pluginapi.KubeletSocket && event.Op&fsnotify.Create == fsnotify.Create {
+				glog.V(0).Infof("inotify: %s created, restarting.", pluginapi.KubeletSocket)
+				restart = true
+			}
+
+		case err := <-watcher.Errors:
+			glog.V(0).Infof("inotify: %s", err)
+
+		case s := <-sigs:
+			switch s {
+			case syscall.SIGHUP:
+				glog.V(0).Info("Received SIGHUP, restarting.")
+				restart = true
+			default:
+				glog.V(0).Infof("Received signal \"%v\", shutting down.", s)
+				for _, devicesInUse := range listDevicesAvailable {
+					if devicesInUse.devicePlugin != nil {
+						devicesInUse.devicePlugin.Stop()
+					}
+				}
+				break L
+			}
+		}
+	}
+}