From 08fb980ad26eafede58f534574644572bf605ff4 Mon Sep 17 00:00:00 2001
From: Kevin Wan <wanjunfeng@gmail.com>
Date: Tue, 13 Apr 2021 00:04:19 +0800
Subject: [PATCH] add syncx.Guard func (#620)

---
 core/syncx/barrier.go      |  9 +++++++--
 core/syncx/barrier_test.go | 16 ++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/core/syncx/barrier.go b/core/syncx/barrier.go
index f790bcfd..0a3c894c 100644
--- a/core/syncx/barrier.go
+++ b/core/syncx/barrier.go
@@ -9,7 +9,12 @@ type Barrier struct {
 
 // Guard guards the given fn on the resource.
 func (b *Barrier) Guard(fn func()) {
-	b.lock.Lock()
-	defer b.lock.Unlock()
+	Guard(&b.lock, fn)
+}
+
+// Guard guards the given fn with lock.
+func Guard(lock sync.Locker, fn func()) {
+	lock.Lock()
+	defer lock.Unlock()
 	fn()
 }
diff --git a/core/syncx/barrier_test.go b/core/syncx/barrier_test.go
index 95cb7574..7e2426ef 100644
--- a/core/syncx/barrier_test.go
+++ b/core/syncx/barrier_test.go
@@ -38,3 +38,19 @@ func TestBarrierPtr_Guard(t *testing.T) {
 	wg.Wait()
 	assert.Equal(t, total, count)
 }
+
+func TestGuard(t *testing.T) {
+	const total = 10000
+	var count int
+	var lock sync.Mutex
+	wg := new(sync.WaitGroup)
+	wg.Add(total)
+	for i := 0; i < total; i++ {
+		go Guard(&lock, func() {
+			count++
+			wg.Done()
+		})
+	}
+	wg.Wait()
+	assert.Equal(t, total, count)
+}