diff --git a/pkg/cgfsmon/private.go b/pkg/cgfsmon/private.go
index 9cb9ce2..cacad9e 100644
--- a/pkg/cgfsmon/private.go
+++ b/pkg/cgfsmon/private.go
@@ -3,12 +3,86 @@ package cgfsmon
 import (
 	"context"
 	"errors"
+	"io/fs"
 	"os"
+	"path/filepath"
+	"strings"
 
 	"github.com/black-desk/cgtproxy/pkg/types"
 	fsevents "github.com/tywkeene/go-fsevents"
 )
 
+func (m *CGroupFSMonitor) walkFn(ctx context.Context) func(path string, d fs.DirEntry, err error) error {
+	return func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			if errors.Is(err, fs.ErrNotExist) {
+				m.log.Debug(
+					"Cgroup had been removed.",
+					"path", path,
+				)
+				err = nil
+			}
+			m.log.Errorw(
+				"Errors occurred while first time going through cgroupfs.",
+				"path", path,
+				"error", err,
+			)
+			err = nil
+		}
+
+		if !d.IsDir() {
+			return nil
+		}
+
+		cgEvent := &types.CGroupEvent{
+			Path:      path,
+			EventType: types.CgroupEventTypeNew,
+		}
+
+		err = m.send(ctx, cgEvent)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	}
+}
+
+func (m *CGroupFSMonitor) walk(ctx context.Context, path string) {
+	err := filepath.WalkDir(path, m.walkFn(ctx))
+	if err == nil {
+		return
+	}
+
+	return
+}
+
+func (m *CGroupFSMonitor) send(ctx context.Context, cgEvent *types.CGroupEvent) (err error) {
+	path := strings.TrimRight(cgEvent.Path, "/")
+	cgEvent.Path = path
+
+	if cgEvent.Path == string(m.root) {
+		// NOTE: Ignore cgroup root.
+		return nil
+	}
+
+	m.log.Debugw("New cgroup envent.",
+		"event", cgEvent,
+	)
+
+	select {
+	case <-ctx.Done():
+		err = ctx.Err()
+		return
+	case m.events <- *cgEvent:
+		m.log.Debugw("Cgroup event sent.",
+			"path", path,
+		)
+	}
+
+	return
+}
+
 type handle struct {
 	ctx context.Context
 	mon *CGroupFSMonitor
diff --git a/pkg/cgfsmon/public.go b/pkg/cgfsmon/public.go
index 70c150a..9820074 100644
--- a/pkg/cgfsmon/public.go
+++ b/pkg/cgfsmon/public.go
@@ -2,10 +2,6 @@ package cgfsmon
 
 import (
 	"context"
-	"errors"
-	"io/fs"
-	"path/filepath"
-	"strings"
 
 	"github.com/black-desk/cgtproxy/pkg/types"
 	. "github.com/black-desk/lib/go/errwrap"
@@ -16,77 +12,6 @@ func (w *CGroupFSMonitor) Events() <-chan types.CGroupEvent {
 	return w.events
 }
 
-func (m *CGroupFSMonitor) walkFn(ctx context.Context) func(path string, d fs.DirEntry, err error) error {
-	return func(path string, d fs.DirEntry, err error) error {
-		if err != nil {
-			if errors.Is(err, fs.ErrNotExist) {
-				m.log.Debug(
-					"Cgroup had been removed.",
-					"path", path,
-				)
-				err = nil
-			}
-			m.log.Errorw(
-				"Errors occurred while first time going through cgroupfs.",
-				"path", path,
-				"error", err,
-			)
-			err = nil
-		}
-
-		if !d.IsDir() {
-			return nil
-		}
-
-		cgEvent := &types.CGroupEvent{
-			Path:      path,
-			EventType: types.CgroupEventTypeNew,
-		}
-
-		err = m.send(ctx, cgEvent)
-		if err != nil {
-			return err
-		}
-
-		return nil
-	}
-}
-
-func (m *CGroupFSMonitor) walk(ctx context.Context, path string) {
-	err := filepath.WalkDir(path, m.walkFn(ctx))
-	if err == nil {
-		return
-	}
-
-	return
-}
-
-func (m *CGroupFSMonitor) send(ctx context.Context, cgEvent *types.CGroupEvent) (err error) {
-	path := strings.TrimRight(cgEvent.Path, "/")
-	cgEvent.Path = path
-
-	if cgEvent.Path == string(m.root) {
-		// NOTE: Ignore cgroup root.
-		return nil
-	}
-
-	m.log.Debugw("New cgroup envent.",
-		"event", cgEvent,
-	)
-
-	select {
-	case <-ctx.Done():
-		err = ctx.Err()
-		return
-	case m.events <- *cgEvent:
-		m.log.Debugw("Cgroup event sent.",
-			"path", path,
-		)
-	}
-
-	return
-}
-
 func (w *CGroupFSMonitor) Run(ctx context.Context) (err error) {
 	defer Wrap(&err, "running filesystem watcher")
 	defer close(w.events)