func BenchmarkRWMutexR1(b *testing.B) {
var mtx sync.RWMutex
for i := 0; i < b.N; i++ {
mtx.RLock()
mtx.RUnlock()
}
}
func TestStream_Open_WithOp(t *testing.T) {
src := newStrSrc([]string{"HELLO", "WORLD", "HOW", "ARE", "YOU"})
snk := newStrSink()
op1 := api.UnFunc(func(ctx context.Context, data interface{}) interface{} {
str := data.(string)
return len(str)
})
var m sync.RWMutex
runeCount := 0
op2 := api.UnFunc(func(ctx context.Context, data interface{}) interface{} {
length := data.(int)
m.Lock()
runeCount += length
m.Unlock()
return nil
})
strm := New().From(src).Transform(op1).Transform(op2).To(snk)
select {
case err := <-strm.Open():
if err != nil {
t.Fatal(err)
}
case <-time.After(50 * time.Millisecond):
t.Fatal("Waited too long ...")
}
m.RLock()
if runeCount != 19 {
t.Fatal("Data not streaming, runeCount 19, got ", runeCount)
}
m.RUnlock()
}
func main() {
var l *sync.RWMutex
l = new(sync.RWMutex)
l.RUnlock()
fmt.Println("l")
l.RLock()
}
func Task(f func(in Receiver, out Sender)) Sender {
var running bool
var l sync.RWMutex
inR, inW := Pipe()
outR, outW := Pipe()
obj := NewServer()
obj.OnAttach(Handler(func(msg *Message) error {
msg.Ret.Send(&Message{Verb: Ack, Ret: inW})
fmt.Printf("copying task output from %#v to %#v\n", outR, msg.Ret)
defer fmt.Printf("(DONE) copying task output from %#v to %#v\n", outR, msg.Ret)
Copy(msg.Ret, outR)
return nil
}))
obj.OnStart(Handler(func(msg *Message) error {
l.RLock()
r := running
l.RUnlock()
if r {
return fmt.Errorf("already running")
}
l.Lock()
go f(inR, outW)
running = true
l.Unlock()
msg.Ret.Send(&Message{Verb: Ack})
return nil
}))
return obj
}
func TestSendReceiveWithWait(t *testing.T) {
conn := NewConn()
conn.ReceiveWait = true
conn.Command("HGETALL", "person:1").ExpectMap(map[string]string{
"name": "Mr. Johson",
"age": "42",
})
conn.Command("HGETALL", "person:2").ExpectMap(map[string]string{
"name": "Ms. Jennifer",
"age": "28",
})
ids := []string{"1", "2"}
for _, id := range ids {
conn.Send("HGETALL", fmt.Sprintf("person:%s", id))
}
var people []Person
var peopleLock sync.RWMutex
go func() {
for i := 0; i < len(ids); i++ {
values, err := redis.Values(conn.Receive())
if err != nil {
t.Fatal(err)
}
var person Person
err = redis.ScanStruct(values, &person)
if err != nil {
t.Fatal(err)
}
peopleLock.Lock()
people = append(people, person)
peopleLock.Unlock()
}
}()
for i := 0; i < len(ids); i++ {
conn.ReceiveNow <- true
}
time.Sleep(10 * time.Millisecond)
peopleLock.RLock()
defer peopleLock.RUnlock()
if len(people) != 2 {
t.Fatalf("Wrong number of people. Expected '2' and got '%d'", len(people))
}
if people[0].Name != "Mr. Johson" || people[1].Name != "Ms. Jennifer" {
t.Error("People name order are wrong")
}
if people[0].Age != 42 || people[1].Age != 28 {
t.Error("People age order are wrong")
}
}
// Readers-Writers
func rwlockExample() {
runtime.GOMAXPROCS(runtime.NumCPU())
// rand.Seed(time.Now().UnixNano())
// rand.Seed(0)
l := new(sync.RWMutex)
wg := new(sync.WaitGroup)
for i := 0; i < 10; i++ {
wg.Add(1)
go func(i int) {
r := rand.Intn(10)
time.Sleep(50 * time.Millisecond)
if r < 5 {
// I am reader.
fmt.Printf("Reader waiting %d\n", i)
l.RLock()
fmt.Printf("go reader %d\n", i)
l.RUnlock()
wg.Done()
} else {
// I am writer
fmt.Printf("Writer waiting %d\n", i)
l.Lock()
fmt.Printf("go writer %d\n", i)
time.Sleep(50 * time.Millisecond)
l.Unlock()
wg.Done()
}
}(i)
}
wg.Wait()
}
//GetCache checks nodes in lookuptable have the cache.
//if found gets records.
func GetCache(background bool, c *thread.Cache) bool {
const searchDepth = 5 // Search node size
ns := manager.NodesForGet(c.Datfile, searchDepth)
found := false
var wg sync.WaitGroup
var mutex sync.RWMutex
dm := NewManger(c)
for _, n := range ns {
wg.Add(1)
go func(n *node.Node) {
defer wg.Done()
if !headWithRange(n, c, dm) {
return
}
if getWithRange(n, c, dm) {
mutex.Lock()
found = true
mutex.Unlock()
return
}
}(n)
}
if background {
bg(c, &wg)
} else {
wg.Wait()
}
mutex.RLock()
defer mutex.RUnlock()
return found
}
func TestNoRaceRWMutexMultipleReaders(t *testing.T) {
var mu sync.RWMutex
x := int64(0)
ch := make(chan bool, 3)
go func() {
mu.Lock()
defer mu.Unlock()
x = 2
ch <- true
}()
go func() {
mu.RLock()
y := x + 1
_ = y
mu.RUnlock()
ch <- true
}()
go func() {
mu.RLock()
y := x + 2
_ = y
mu.RUnlock()
ch <- true
}()
<-ch
<-ch
<-ch
}
func TestRaceRWMutexMultipleReaders(t *testing.T) {
var mu sync.RWMutex
var x, y int64 = 0, 1
ch := make(chan bool, 3)
go func() {
mu.Lock()
defer mu.Unlock()
x = 2
ch <- true
}()
go func() {
mu.RLock()
y = x + 1
mu.RUnlock()
ch <- true
}()
go func() {
mu.RLock()
y = x + 2
mu.RUnlock()
ch <- true
}()
<-ch
<-ch
<-ch
_ = y
}
func (lm *lockManager) UnlockPolicy(lock *sync.RWMutex, lockType bool) {
if lockType == exclusive {
lock.Unlock()
} else {
lock.RUnlock()
}
}
func BenchmarkRWMutexRLock(b *testing.B) {
var l sync.RWMutex
for i := 0; i < b.N; i++ {
l.RLock()
l.RUnlock()
}
}
func compileVariableNode(node *parse.VariableNode, dotType reflect.Type, args []parse.Node, finalType reflect.Type) (cmd command, retType reflect.Type) {
var mu sync.RWMutex
type key struct {
dotType, finalType reflect.Type
}
cache := make(map[key]command)
name := node.Ident[0]
cmd = func(s state, dot, final interface{}) interface{} {
value := s.varValue(name)
if len(node.Ident) == 1 {
return value.Interface()
}
if dotType == nil {
dotType = reflect.ValueOf(dot).Type()
}
if finalType == nil && final != nil {
finalType = reflect.ValueOf(final).Type()
}
k := key{dotType, finalType}
mu.RLock()
f, exist := cache[k]
mu.RUnlock()
if !exist {
f, _ = compileFieldChain(node.Ident[1:], dotType, args, finalType)
mu.Lock()
cache[k] = f
mu.Unlock()
}
return f(s, dot, value)
}
return
}
// Returns an Action that runs the original Action when there is no cached value.
// The cached value is unset after the given ttl (time to live) duration.
// A negative ttl will permanently cache
func (a Action) cache(ttl time.Duration) Action {
var data map[string]interface{}
lock := sync.RWMutex{}
return func(r *http.Request) (map[string]interface{}, error) {
lock.RLock()
if data != nil {
lock.RUnlock()
return data, nil
}
lock.RUnlock()
lock.Lock()
defer lock.Unlock()
var err error
data, err = a(r)
if data != nil {
if ttl > 0 {
time.AfterFunc(ttl, func() {
lock.Lock()
data = nil
lock.Unlock()
})
}
}
return data, err
}
}
func compileFieldDynamic(name string, args []parse.Node) lookupFn {
type key struct {
valueType reflect.Type
finalType reflect.Type
}
var m sync.RWMutex
cache := make(map[key]lookupFn)
return func(s state, value reflect.Value, final interface{}) reflect.Value {
valueType := value.Elem().Type()
var finalType reflect.Type
if v := reflect.ValueOf(final); v.IsValid() {
finalType = v.Type()
}
k := key{valueType, finalType}
m.RLock()
f, exist := cache[k]
m.RUnlock()
if !exist {
f, _ = compileField(valueType, name, args, finalType)
m.Lock()
cache[k] = f
m.Unlock()
}
return f(s, value.Elem(), final)
}
}
func main() {
Case := Init(6)
fmt.Printf("DEADLOCK\n")
c := make(chan int)
var mu sync.RWMutex
done := make(chan bool)
go func() {
time.Sleep(sleep3[Case][0])
mu.RLock()
c <- 1
mu.RUnlock()
done <- true
}()
go func() {
time.Sleep(sleep3[Case][1])
mu.RLock()
<-c
mu.RUnlock()
done <- true
}()
time.Sleep(sleep3[Case][2])
mu.Lock()
mu.Unlock()
<-done
<-done
}
//读文件
func (helper *FileHelper) ReadFile(filename string) (string, error) {
lock := new(sync.RWMutex)
lock.RLock()
var content string
file, err := os.Open(filename)
if err != nil {
fmt.Println("file open error:", err)
return content, err
}
reader := bufio.NewReader(file)
for {
line, _, err := reader.ReadLine()
if err != nil {
break
}
content += string(line) + ","
}
content = strings.TrimRight(content, ",")
file.Close()
lock.RUnlock()
fmt.Println(content)
return content, err
}
func main() {
Case := Init(6)
fmt.Printf("DEADLOCK\n")
c := make(chan int)
var mu sync.RWMutex
done := make(chan bool)
go func() {
time.Sleep(sleep3[Case][0])
mu.RLock()
c <- 1
mu.RUnlock()
done <- true
}()
go func() {
time.Sleep(sleep3[Case][1])
mu.RLock()
loop:
for {
select {
case <-c:
break loop
case <-time.After(time.Millisecond):
}
}
mu.RUnlock()
done <- true
}()
time.Sleep(sleep3[Case][2])
mu.Lock()
mu.Unlock()
<-done
<-done
}
// verifies the cacheWatcher.process goroutine is properly cleaned up even if
// the writes to cacheWatcher.result channel is blocked.
func TestCacheWatcherCleanupNotBlockedByResult(t *testing.T) {
var lock sync.RWMutex
count := 0
filter := func(string, labels.Set, fields.Set) bool { return true }
forget := func(bool) {
lock.Lock()
defer lock.Unlock()
count++
}
initEvents := []watchCacheEvent{
{Object: &api.Pod{}},
{Object: &api.Pod{}},
}
// set the size of the buffer of w.result to 0, so that the writes to
// w.result is blocked.
w := newCacheWatcher(0, 0, initEvents, filter, forget)
w.Stop()
if err := wait.PollImmediate(1*time.Second, 5*time.Second, func() (bool, error) {
lock.RLock()
defer lock.RUnlock()
return count == 2, nil
}); err != nil {
t.Fatalf("expected forget() to be called twice, because sendWatchCacheEvent should not be blocked by the result channel: %v", err)
}
}
// Serve starts an endless loop that reads FTP commands from the client and
// responds appropriately. terminated is a channel that will receive a true
// message when the connection closes. This loop will be running inside a
// goroutine, so use this channel to be notified when the connection can be
// cleaned up.
func (ftpConn *ftpConn) Serve() {
defer func() {
if closer, ok := ftpConn.driver.(io.Closer); ok {
closer.Close()
}
}()
ftpConn.logger.Printf("Connection Established (%s)", ftpConn.conn.RemoteAddr())
// send welcome
ftpConn.writeMessage(220, ftpConn.serverName)
// read commands
var readMutex sync.RWMutex
cmdCh := make(chan *BoundCommand, 0)
go func() {
defer func() {
if r := recover(); r != nil {
ftpConn.logger.Printf("Recovered in ftpConn Serve: %s", r)
}
ftpConn.Close()
close(cmdCh)
}()
for {
readMutex.RLock()
line, err := ftpConn.controlReader.ReadString('\n')
readMutex.RUnlock()
if err != nil {
return
} else {
cmdObj := ftpConn.receiveLine(line)
if cmdObj != nil {
if !cmdObj.CmdObj.Async() {
readMutex.Lock()
}
select {
case cmdCh <- cmdObj:
continue
case _ = <-time.After(10 * time.Second):
return
}
}
}
}
}()
for cmd := range cmdCh {
cmd.CmdObj.Execute(ftpConn, cmd.Param)
if !cmd.CmdObj.Async() {
readMutex.Unlock()
}
}
ftpConn.logger.Print("Connection Terminated")
}
func BenchmarkConcurrentRWMutex(b *testing.B) {
var mu sync.RWMutex
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
mu.RLock()
mu.RUnlock()
}
})
}
func (con FeedUpdateNotificator) Handler(c context.Context) http.HandlerFunc {
var mutex sync.RWMutex
receivers := make(map[chan readeef.Feed]bool)
go func() {
for {
select {
case feed := <-con.updateFeed:
mutex.RLock()
readeef.Debug.Printf("Feed %s updated. Notifying %d receivers.", feed.Link, len(receivers))
for receiver, _ := range receivers {
receiver <- feed
}
mutex.RUnlock()
}
}
}()
return func(w http.ResponseWriter, r *http.Request) {
var err error
receiver := make(chan readeef.Feed)
mutex.Lock()
receivers[receiver] = true
mutex.Unlock()
defer func() {
mutex.Lock()
delete(receivers, receiver)
mutex.Unlock()
}()
f := <-receiver
readeef.Debug.Println("Feed " + f.Link + " updated")
resp := map[string]interface{}{"Feed": feed{
Id: f.Id, Title: f.Title, Description: f.Description,
Link: f.Link, Image: f.Image,
}}
var b []byte
if err == nil {
b, err = json.Marshal(resp)
}
if err != nil {
webfw.GetLogger(c).Print(err)
w.WriteHeader(http.StatusInternalServerError)
return
}
w.Write(b)
}
}
func main() {
m := new(sync.RWMutex)
println("new RWMutex")
m.RLock()
println("got RLock")
m.RUnlock()
m.Lock()
println("Got Lock")
}
// discoverAndPollChromecasts runs an infinite loop, discovering and polling
// chromecast devices in the local network for whether they are currently
// playing. The first discovered device is used.
func discoverAndPollChromecasts() {
var chromecastsMu sync.RWMutex
chromecasts := make(map[string]chan bool)
entriesCh := make(chan *mdns.ServiceEntry, 5)
go mdnsLookup(entriesCh)
for {
select {
case entry := <-entriesCh:
if !strings.Contains(entry.Name, castService) {
continue
}
var deviceType chromecastDevice
for _, field := range entry.InfoFields {
if !strings.HasPrefix(field, "md=") {
continue
}
if field == "md=Chromecast" {
deviceType = chromecast
} else if field == "md=Chromecast Audio" {
deviceType = chromecastAudio
}
}
hostport := fmt.Sprintf("%s:%d", entry.Addr, entry.Port)
chromecastsMu.RLock()
_, exists := chromecasts[hostport]
chromecastsMu.RUnlock()
if exists {
continue
}
fmt.Printf("Found new chromecast at %q: %+v\n", hostport, entry)
done := make(chan bool)
chromecastsMu.Lock()
chromecasts[hostport] = done
chromecastsMu.Unlock()
go func(deviceType chromecastDevice, done chan bool, hostport string) {
err := pollChromecast(deviceType, done, hostport)
if err != nil {
log.Printf("Error polling chromecast %s:%d: %v\n", entry.Addr, entry.Port, err)
}
chromecastsMu.Lock()
delete(chromecasts, hostport)
chromecastsMu.Unlock()
}(deviceType, done, hostport)
stateMu.Lock()
state.chromecastPlaying = false
stateMu.Unlock()
stateChanged.Broadcast()
case <-time.After(10 * time.Second):
log.Printf("Starting new MDNS lookup\n")
go mdnsLookup(entriesCh)
}
}
}
func BenchmarkStreamOp_Exec(b *testing.B) {
ctx := context.Background()
o := NewStreamOp(ctx)
N := b.N
chanSize := func() int {
if N == 1 {
return N
}
return int(float64(0.5) * float64(N))
}()
in := make(chan interface{}, chanSize)
o.SetInput(in)
go func() {
for i := 0; i < N; i++ {
in <- []string{
testutil.GenWord(),
testutil.GenWord(),
testutil.GenWord(),
}
}
close(in)
}()
counter := 0
expected := N * 3
var m sync.RWMutex
// process output
done := make(chan struct{})
go func() {
defer close(done)
for _ = range o.GetOutput() {
m.Lock()
counter++
m.Unlock()
}
}()
if err := o.Exec(); err != nil {
b.Fatal("Error during execution:", err)
}
select {
case <-done:
case <-time.After(time.Second * 60):
b.Fatal("Took too long")
}
m.RLock()
b.Logf("Input %d, counted %d", N, counter)
if counter != expected {
b.Fatalf("Expected %d items processed, got %d", expected, counter)
}
m.RUnlock()
}
func BenchmarkRWMutexR(b *testing.B) {
b.SetParallelism(10)
var mtx sync.RWMutex
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
mtx.RLock()
mtx.RUnlock()
}
})
}
func (p *genericPacketTransport) acceptConnections(clientMap map[string]*genericPacketClient,
clientMapLock sync.RWMutex) {
log.Println("Started accepting clients")
var pkt [65535]byte
var n int
var err error
var addr net.Addr
for {
n, addr, err = p.conn.ReadFrom(pkt[:])
if err != nil {
log.Printf("Error reading new packet: %s\n")
}
log.Printf("Got packet of length %d\n", n)
clientMapLock.RLock()
client, found := clientMap[addr.String()]
clientMapLock.RUnlock()
if !found {
log.Printf("Got new client: %s\n", addr)
// We create a new client that will proxy all writes to this
// transport's underlying send channel.
recv_ch := make(chan []byte)
send_ch := make(chan []byte)
// When the client is closed, it needs to remove itself from the map.
onClose := func() {
clientMapLock.Lock()
delete(clientMap, addr.String())
clientMapLock.Unlock()
}
client = &genericPacketClient{
send_ch, recv_ch,
nil, addr,
"host", p.network,
onClose,
}
go client.startAsServerConn(p.send_ch)
clientMapLock.Lock()
clientMap[addr.String()] = client
clientMapLock.Unlock()
p.accept_ch <- client
}
client.RecvChannel() <- pkt[0:n]
}
}
func hasVisitedPage(pms []*PageMap, m *sync.RWMutex, u *url.URL) bool {
m.RLock()
defer m.RUnlock()
for _, pm := range pms {
if pm.URL.String() == u.String() {
return true
}
}
return false
}
func BenchmarkMapGet(b *testing.B) {
b.StopTimer()
cache := map[string]string{"foo": "bar"}
mu := sync.RWMutex{}
b.StartTimer()
for i := 0; i < b.N; i++ {
mu.RLock()
_, _ = cache["foo"]
mu.RUnlock()
}
}
func ConcurrentInterpret(mutex *sync.RWMutex, actives map[string]*LabelNode, rule []string) bool {
mutex.RLock()
for i := range rule {
if actives[rule[i]] == nil {
mutex.RUnlock()
return false
}
}
mutex.RUnlock()
return true
}
func roLock(mu *sync.RWMutex) chan<- bool {
unlock := make(chan bool)
mu.RLock()
go func() {
<-unlock
mu.RUnlock()
}()
return unlock
}