Refector deadlock into detector pkg

pkg/util/threading/deadlock-detector_test.go

@@ -0,0 +1,127 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package threading
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+type fakeExiter struct {
+	format string
+	args   []interface{}
+	exited bool
+}
+
+func (f *fakeExiter) Exitf(format string, args ...interface{}) {
+	f.format = format
+	f.args = args
+	f.exited = true
+}
+
+func TestMaxLockPeriod(t *testing.T) {
+	lock := &sync.RWMutex{}
+	panicked := false
+	func() {
+		defer func() {
+			if r := recover(); r != nil {
+				panicked = true
+			}
+		}()
+		DeadlockWatchdogReadLock(lock, "test lock", 0)
+	}()
+	if !panicked {
+		t.Errorf("expected a panic for a zero max lock period")
+	}
+}
+
+func TestDeadlockWatchdogLocked(t *testing.T) {
+	lock := &sync.RWMutex{}
+	lock.Lock()
+
+	exitCh := make(chan time.Time, 1)
+	fake := fakeExiter{}
+
+	detector := &deadlockDetector{
+		lock:          &rwMutexToLockableAdapter{lock},
+		name:          "test deadlock",
+		exitChannelFn: func() <-chan time.Time { return exitCh },
+		exiter:        &fake,
+	}
+
+	exitCh <- time.Time{}
+
+	detector.run()
+
+	if !fake.exited {
+		t.Errorf("expected to have exited")
+	}
+
+	if len(fake.args) != 1 || fake.args[0].(string) != detector.name {
+		t.Errorf("unexpected args: %v", fake.args)
+	}
+}
+
+func TestDeadlockWatchdogUnlocked(t *testing.T) {
+	lock := &sync.RWMutex{}
+
+	fake := fakeExiter{}
+
+	detector := &deadlockDetector{
+		lock:          &rwMutexToLockableAdapter{lock},
+		name:          "test deadlock",
+		exitChannelFn: func() <-chan time.Time { return time.After(time.Second * 5) },
+		exiter:        &fake,
+	}
+
+	for i := 0; i < 100; i++ {
+		detector.runOnce()
+	}
+
+	if fake.exited {
+		t.Errorf("expected to have not exited")
+	}
+}
+
+func TestDeadlockWatchdogLocking(t *testing.T) {
+	lock := &sync.RWMutex{}
+
+	fake := fakeExiter{}
+
+	go func() {
+		for {
+			lock.Lock()
+			lock.Unlock()
+		}
+	}()
+
+	detector := &deadlockDetector{
+		lock:          &rwMutexToLockableAdapter{lock},
+		name:          "test deadlock",
+		exitChannelFn: func() <-chan time.Time { return time.After(time.Second * 5) },
+		exiter:        &fake,
+	}
+
+	for i := 0; i < 100; i++ {
+		detector.runOnce()
+	}
+
+	if fake.exited {
+		t.Errorf("expected to have not exited")
+	}
+}