Merge pull request google#1962 from dashpole/cherrypick_1959

Revert "Switch from Inotify to Fsnotify"

container/common/helpers.go

@@ -40,7 +40,7 @@ func DebugInfo(watches map[string][]string) map[string][]string {
 			lines = append(lines, fmt.Sprintf("\t%s", cg))
 		}
 	}
-	out["Fsnotify watches"] = lines
+	out["Inotify watches"] = lines
 
 	return out
 }

container/common/fsnotify_watcher.go → container/common/inotify_watcher.go

@@ -17,15 +17,15 @@ package common
 import (
 	"sync"
 
-	"github.com/fsnotify/fsnotify"
+	"golang.org/x/exp/inotify"
 )
 
-// Watcher for container-related fsnotify events in the cgroup hierarchy.
+// Watcher for container-related inotify events in the cgroup hierarchy.
 //
 // Implementation is thread-safe.
-type FsnotifyWatcher struct {
-	// Underlying fsnotify watcher.
-	watcher *fsnotify.Watcher
+type InotifyWatcher struct {
+	// Underlying inotify watcher.
+	watcher *inotify.Watcher
 
 	// Map of containers being watched to cgroup paths watched for that container.
 	containersWatched map[string]map[string]bool
@@ -34,28 +34,28 @@ type FsnotifyWatcher struct {
 	lock sync.Mutex
 }
 
-func NewFsnotifyWatcher() (*FsnotifyWatcher, error) {
-	w, err := fsnotify.NewWatcher()
+func NewInotifyWatcher() (*InotifyWatcher, error) {
+	w, err := inotify.NewWatcher()
 	if err != nil {
 		return nil, err
 	}
 
-	return &FsnotifyWatcher{
+	return &InotifyWatcher{
 		watcher:           w,
 		containersWatched: make(map[string]map[string]bool),
 	}, nil
 }
 
 // Add a watch to the specified directory. Returns if the container was already being watched.
-func (iw *FsnotifyWatcher) AddWatch(containerName, dir string) (bool, error) {
+func (iw *InotifyWatcher) AddWatch(containerName, dir string) (bool, error) {
 	iw.lock.Lock()
 	defer iw.lock.Unlock()
 
 	cgroupsWatched, alreadyWatched := iw.containersWatched[containerName]
 
-	// Register an fsnotify notification.
+	// Register an inotify notification.
 	if !cgroupsWatched[dir] {
-		err := iw.watcher.Add(dir)
+		err := iw.watcher.AddWatch(dir, inotify.IN_CREATE|inotify.IN_DELETE|inotify.IN_MOVE)
 		if err != nil {
 			return alreadyWatched, err
 		}
@@ -74,7 +74,7 @@ func (iw *FsnotifyWatcher) AddWatch(containerName, dir string) (bool, error) {
 }
 
 // Remove watch from the specified directory. Returns if this was the last watch on the specified container.
-func (iw *FsnotifyWatcher) RemoveWatch(containerName, dir string) (bool, error) {
+func (iw *InotifyWatcher) RemoveWatch(containerName, dir string) (bool, error) {
 	iw.lock.Lock()
 	defer iw.lock.Unlock()
 
@@ -84,9 +84,9 @@ func (iw *FsnotifyWatcher) RemoveWatch(containerName, dir string) (bool, error)
 		return false, nil
 	}
 
-	// Remove the fsnotify watch if it exists.
+	// Remove the inotify watch if it exists.
 	if cgroupsWatched[dir] {
-		err := iw.watcher.Remove(dir)
+		err := iw.watcher.RemoveWatch(dir)
 		if err != nil {
 			return false, nil
 		}
@@ -103,22 +103,22 @@ func (iw *FsnotifyWatcher) RemoveWatch(containerName, dir string) (bool, error)
 }
 
 // Errors are returned on this channel.
-func (iw *FsnotifyWatcher) Error() chan error {
-	return iw.watcher.Errors
+func (iw *InotifyWatcher) Error() chan error {
+	return iw.watcher.Error
 }
 
 // Events are returned on this channel.
-func (iw *FsnotifyWatcher) Event() chan fsnotify.Event {
-	return iw.watcher.Events
+func (iw *InotifyWatcher) Event() chan *inotify.Event {
+	return iw.watcher.Event
 }
 
-// Closes the fsnotify watcher.
-func (iw *FsnotifyWatcher) Close() error {
+// Closes the inotify watcher.
+func (iw *InotifyWatcher) Close() error {
 	return iw.watcher.Close()
 }
 
 // Returns a map of containers to the cgroup paths being watched.
-func (iw *FsnotifyWatcher) GetWatches() map[string][]string {
+func (iw *InotifyWatcher) GetWatches() map[string][]string {
 	out := make(map[string][]string, len(iw.containersWatched))
 	for k, v := range iw.containersWatched {
 		out[k] = mapToSlice(v)

container/raw/factory.go

@@ -40,8 +40,8 @@ type rawFactory struct {
 	// Information about mounted filesystems.
 	fsInfo fs.FsInfo
 
-	// Watcher for fsnotify events.
-	watcher *common.FsnotifyWatcher
+	// Watcher for inotify events.
+	watcher *common.InotifyWatcher
 
 	// List of metrics to be ignored.
 	ignoreMetrics map[container.MetricKind]struct{}
@@ -78,7 +78,7 @@ func Register(machineInfoFactory info.MachineInfoFactory, fsInfo fs.FsInfo, igno
 		return fmt.Errorf("failed to find supported cgroup mounts for the raw factory")
 	}
 
-	watcher, err := common.NewFsnotifyWatcher()
+	watcher, err := common.NewInotifyWatcher()
 	if err != nil {
 		return err
 	}

container/raw/handler.go

@@ -49,7 +49,7 @@ func isRootCgroup(name string) bool {
 	return name == "/"
 }
 
-func newRawContainerHandler(name string, cgroupSubsystems *libcontainer.CgroupSubsystems, machineInfoFactory info.MachineInfoFactory, fsInfo fs.FsInfo, watcher *common.FsnotifyWatcher, rootFs string, ignoreMetrics container.MetricSet) (container.ContainerHandler, error) {
+func newRawContainerHandler(name string, cgroupSubsystems *libcontainer.CgroupSubsystems, machineInfoFactory info.MachineInfoFactory, fsInfo fs.FsInfo, watcher *common.InotifyWatcher, rootFs string, ignoreMetrics container.MetricSet) (container.ContainerHandler, error) {
 	cgroupPaths := common.MakeCgroupPaths(cgroupSubsystems.MountPoints, name)
 
 	cHints, err := common.GetContainerHintsFromFile(*common.ArgContainerHints)

manager/watcher/raw/raw.go

@@ -27,8 +27,8 @@ import (
 	"github.com/google/cadvisor/container/libcontainer"
 	"github.com/google/cadvisor/manager/watcher"
 
-	"github.com/fsnotify/fsnotify"
 	"github.com/golang/glog"
+	"golang.org/x/exp/inotify"
 )
 
 type rawContainerWatcher struct {
@@ -37,8 +37,8 @@ type rawContainerWatcher struct {
 
 	cgroupSubsystems *libcontainer.CgroupSubsystems
 
-	// Fsnotify event watcher.
-	watcher *common.FsnotifyWatcher
+	// Inotify event watcher.
+	watcher *common.InotifyWatcher
 
 	// Signal for watcher thread to stop.
 	stopWatcher chan error
@@ -53,7 +53,7 @@ func NewRawContainerWatcher() (watcher.ContainerWatcher, error) {
 		return nil, fmt.Errorf("failed to find supported cgroup mounts for the raw factory")
 	}
 
-	watcher, err := common.NewFsnotifyWatcher()
+	watcher, err := common.NewInotifyWatcher()
 	if err != nil {
 		return nil, err
 	}
@@ -121,7 +121,7 @@ func (self *rawContainerWatcher) watchDirectory(events chan watcher.ContainerEve
 		if cleanup {
 			_, err := self.watcher.RemoveWatch(containerName, dir)
 			if err != nil {
-				glog.Warningf("Failed to remove fsnotify watch for %q: %v", dir, err)
+				glog.Warningf("Failed to remove inotify watch for %q: %v", dir, err)
 			}
 		}
 	}()
@@ -163,16 +163,18 @@ func (self *rawContainerWatcher) watchDirectory(events chan watcher.ContainerEve
 	return alreadyWatching, nil
 }
 
-func (self *rawContainerWatcher) processEvent(event fsnotify.Event, events chan watcher.ContainerEvent) error {
-	// Convert the fsnotify event type to a container create or delete.
+func (self *rawContainerWatcher) processEvent(event *inotify.Event, events chan watcher.ContainerEvent) error {
+	// Convert the inotify event type to a container create or delete.
 	var eventType watcher.ContainerEventType
 	switch {
-	case event.Op == fsnotify.Create:
+	case (event.Mask & inotify.IN_CREATE) > 0:
 		eventType = watcher.ContainerAdd
-	case event.Op == fsnotify.Remove:
+	case (event.Mask & inotify.IN_DELETE) > 0:
 		eventType = watcher.ContainerDelete
-	case event.Op == fsnotify.Rename:
+	case (event.Mask & inotify.IN_MOVED_FROM) > 0:
 		eventType = watcher.ContainerDelete
+	case (event.Mask & inotify.IN_MOVED_TO) > 0:
+		eventType = watcher.ContainerAdd
 	default:
 		// Ignore other events.
 		return nil

utils/tail/tail.go

@@ -24,8 +24,8 @@ import (
 	"sync"
 	"time"
 
-	"github.com/fsnotify/fsnotify"
 	"github.com/golang/glog"
+	"golang.org/x/exp/inotify"
 )
 
 type Tail struct {
@@ -35,7 +35,7 @@ type Tail struct {
 	filename   string
 	file       *os.File
 	stop       chan bool
-	watcher    *fsnotify.Watcher
+	watcher    *inotify.Watcher
 }
 
 const (
@@ -60,9 +60,9 @@ func newTail(filename string) (*Tail, error) {
 	}
 	var err error
 	t.stop = make(chan bool)
-	t.watcher, err = fsnotify.NewWatcher()
+	t.watcher, err = inotify.NewWatcher()
 	if err != nil {
-		return nil, fmt.Errorf("fsnotify init failed on %s: %v", t.filename, err)
+		return nil, fmt.Errorf("inotify init failed on %s: %v", t.filename, err)
 	}
 	// Initialize readerErr as io.EOF, so that the reader can work properly
 	// during initialization.
@@ -141,15 +141,15 @@ func (t *Tail) watchFile() error {
 	defer t.file.Close()
 
 	watchDir := filepath.Dir(t.filename)
-	err = t.watcher.Add(watchDir)
+	err = t.watcher.AddWatch(watchDir, inotify.IN_MOVED_FROM|inotify.IN_DELETE)
 	if err != nil {
 		return fmt.Errorf("Failed to add watch to directory %s: %v", watchDir, err)
 	}
-	defer t.watcher.Remove(watchDir)
+	defer t.watcher.RemoveWatch(watchDir)
 
 	for {
 		select {
-		case event := <-t.watcher.Events:
+		case event := <-t.watcher.Event:
 			eventPath := filepath.Clean(event.Name) // Directory events have an extra '/'
 			if eventPath == t.filename {
 				glog.V(4).Infof("Log file %s moved/deleted", t.filename)