fix: service group not working well when callback takes long time (#4531)

Signed-off-by: kevin <wanjunfeng@gmail.com>

core/proc/shutdown.go

@@ -82,6 +82,9 @@ func (lm *listenerManager) addListener(fn func()) (waitForCalled func()) {
 	})
 	lm.lock.Unlock()
 
+	// we can return lm.waitGroup.Wait directly,
+	// but we want to make the returned func more readable.
+	// creating an extra closure would be negligible in practice.
 	return func() {
 		lm.waitGroup.Wait()
 	}

core/proc/shutdown_test.go

@@ -3,6 +3,7 @@
 package proc
 
 import (
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -29,6 +30,42 @@ func TestShutdown(t *testing.T) {
 	assert.Equal(t, 3, val)
 }
 
+func TestShutdownWithMultipleServices(t *testing.T) {
+	SetTimeToForceQuit(time.Hour)
+	assert.Equal(t, time.Hour, delayTimeBeforeForceQuit)
+
+	var val int32
+	called1 := AddShutdownListener(func() {
+		atomic.AddInt32(&val, 1)
+	})
+	called2 := AddShutdownListener(func() {
+		atomic.AddInt32(&val, 2)
+	})
+	Shutdown()
+	called1()
+	called2()
+
+	assert.Equal(t, int32(3), atomic.LoadInt32(&val))
+}
+
+func TestWrapUpWithMultipleServices(t *testing.T) {
+	SetTimeToForceQuit(time.Hour)
+	assert.Equal(t, time.Hour, delayTimeBeforeForceQuit)
+
+	var val int32
+	called1 := AddWrapUpListener(func() {
+		atomic.AddInt32(&val, 1)
+	})
+	called2 := AddWrapUpListener(func() {
+		atomic.AddInt32(&val, 2)
+	})
+	WrapUp()
+	called1()
+	called2()
+
+	assert.Equal(t, int32(3), atomic.LoadInt32(&val))
+}
+
 func TestNotifyMoreThanOnce(t *testing.T) {
 	ch := make(chan struct{}, 1)