1 files changed, 91 insertions, 0 deletions
diff --git a/libgo/go/sync/mutex_test.go b/libgo/go/sync/mutex_test.go
new file mode 100644
index 0000000000..d0e048ed7a
--- /dev/null
+++ b/libgo/go/sync/mutex_test.go
@@ -0,0 +1,91 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// GOMAXPROCS=10 gotest
+
+package sync_test
+
+import (
+	"runtime"
+	. "sync"
+	"testing"
+)
+
+func HammerSemaphore(s *uint32, loops int, cdone chan bool) {
+	for i := 0; i < loops; i++ {
+		runtime.Semacquire(s)
+		runtime.Semrelease(s)
+	}
+	cdone <- true
+}
+
+func TestSemaphore(t *testing.T) {
+	s := new(uint32)
+	*s = 1
+	c := make(chan bool)
+	for i := 0; i < 10; i++ {
+		go HammerSemaphore(s, 1000, c)
+	}
+	for i := 0; i < 10; i++ {
+		<-c
+	}
+}
+
+func BenchmarkUncontendedSemaphore(b *testing.B) {
+	s := new(uint32)
+	*s = 1
+	HammerSemaphore(s, b.N, make(chan bool, 2))
+}
+
+func BenchmarkContendedSemaphore(b *testing.B) {
+	b.StopTimer()
+	s := new(uint32)
+	*s = 1
+	c := make(chan bool)
+	runtime.GOMAXPROCS(2)
+	b.StartTimer()
+
+	go HammerSemaphore(s, b.N/2, c)
+	go HammerSemaphore(s, b.N/2, c)
+	<-c
+	<-c
+}
+
+
+func HammerMutex(m *Mutex, loops int, cdone chan bool) {
+	for i := 0; i < loops; i++ {
+		m.Lock()
+		m.Unlock()
+	}
+	cdone <- true
+}
+
+func TestMutex(t *testing.T) {
+	m := new(Mutex)
+	c := make(chan bool)
+	for i := 0; i < 10; i++ {
+		go HammerMutex(m, 1000, c)
+	}
+	for i := 0; i < 10; i++ {
+		<-c
+	}
+}
+
+func BenchmarkUncontendedMutex(b *testing.B) {
+	m := new(Mutex)
+	HammerMutex(m, b.N, make(chan bool, 2))
+}
+
+func BenchmarkContendedMutex(b *testing.B) {
+	b.StopTimer()
+	m := new(Mutex)
+	c := make(chan bool)
+	runtime.GOMAXPROCS(2)
+	b.StartTimer()
+
+	go HammerMutex(m, b.N/2, c)
+	go HammerMutex(m, b.N/2, c)
+	<-c
+	<-c
+}