func parseEvents() ([]*trace.Event, error) {
loader.once.Do(func() {
tracef, err := os.Open(flag.Arg(1))
if err != nil {
loader.err = fmt.Errorf("failed to open trace file: %v", err)
return
}
defer tracef.Close()
// Parse and symbolize.
events, err := trace.Parse(bufio.NewReader(tracef))
if err != nil {
loader.err = fmt.Errorf("failed to parse trace: %v", err)
return
}
err = trace.Symbolize(events, programBinary)
if err != nil {
loader.err = fmt.Errorf("failed to symbolize trace: %v", err)
return
}
loader.events = events
})
return loader.events, loader.err
}
// TestTraceSymbolize tests symbolization and that events has proper stacks.
// In particular that we strip bottom uninteresting frames like goexit,
// top uninteresting frames (runtime guts).
func TestTraceSymbolize(t *testing.T) {
testenv.MustHaveGoBuild(t)
buf := new(bytes.Buffer)
if err := Start(buf); err != nil {
t.Fatalf("failed to start tracing: %v", err)
}
defer Stop() // in case of early return
// Now we will do a bunch of things for which we verify stacks later.
// It is impossible to ensure that a goroutine has actually blocked
// on a channel, in a select or otherwise. So we kick off goroutines
// that need to block first in the hope that while we are executing
// the rest of the test, they will block.
go func() {
select {}
}()
go func() {
var c chan int
c <- 0
}()
go func() {
var c chan int
<-c
}()
done1 := make(chan bool)
go func() {
<-done1
}()
done2 := make(chan bool)
go func() {
done2 <- true
}()
c1 := make(chan int)
c2 := make(chan int)
go func() {
select {
case <-c1:
case <-c2:
}
}()
var mu sync.Mutex
mu.Lock()
go func() {
mu.Lock()
mu.Unlock()
}()
var wg sync.WaitGroup
wg.Add(1)
go func() {
wg.Wait()
}()
cv := sync.NewCond(&sync.Mutex{})
go func() {
cv.L.Lock()
cv.Wait()
cv.L.Unlock()
}()
ln, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
t.Fatalf("failed to listen: %v", err)
}
go func() {
c, err := ln.Accept()
if err != nil {
t.Fatalf("failed to accept: %v", err)
}
c.Close()
}()
rp, wp, err := os.Pipe()
if err != nil {
t.Fatalf("failed to create a pipe: %v", err)
}
defer rp.Close()
defer wp.Close()
pipeReadDone := make(chan bool)
go func() {
var data [1]byte
rp.Read(data[:])
pipeReadDone <- true
}()
time.Sleep(time.Millisecond)
runtime.GC()
runtime.Gosched()
time.Sleep(time.Millisecond) // the last chance for the goroutines above to block
done1 <- true
<-done2
select {
case c1 <- 0:
case c2 <- 0:
}
mu.Unlock()
wg.Done()
cv.Signal()
c, err := net.Dial("tcp", ln.Addr().String())
if err != nil {
t.Fatalf("failed to dial: %v", err)
}
c.Close()
var data [1]byte
wp.Write(data[:])
<-pipeReadDone
Stop()
events, _, err := parseTrace(t, buf)
if err != nil {
t.Fatalf("failed to parse trace: %v", err)
}
err = trace.Symbolize(events, os.Args[0])
if err != nil {
t.Fatalf("failed to symbolize trace: %v", err)
}
// Now check that the stacks are correct.
type frame struct {
Fn string
Line int
}
type eventDesc struct {
Type byte
Stk []frame
}
want := []eventDesc{
{trace.EvGCStart, []frame{
{"runtime.GC", 0},
{"runtime/trace_test.TestTraceSymbolize", 106},
{"testing.tRunner", 0},
}},
{trace.EvGoSched, []frame{
{"runtime/trace_test.TestTraceSymbolize", 107},
{"testing.tRunner", 0},
}},
{trace.EvGoCreate, []frame{
{"runtime/trace_test.TestTraceSymbolize", 39},
{"testing.tRunner", 0},
}},
{trace.EvGoStop, []frame{
{"runtime.block", 0},
{"runtime/trace_test.TestTraceSymbolize.func1", 38},
}},
{trace.EvGoStop, []frame{
{"runtime.chansend1", 0},
{"runtime/trace_test.TestTraceSymbolize.func2", 42},
}},
{trace.EvGoStop, []frame{
{"runtime.chanrecv1", 0},
{"runtime/trace_test.TestTraceSymbolize.func3", 46},
}},
{trace.EvGoBlockRecv, []frame{
{"runtime.chanrecv1", 0},
{"runtime/trace_test.TestTraceSymbolize.func4", 50},
}},
{trace.EvGoUnblock, []frame{
{"runtime.chansend1", 0},
{"runtime/trace_test.TestTraceSymbolize", 109},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSend, []frame{
{"runtime.chansend1", 0},
{"runtime/trace_test.TestTraceSymbolize.func5", 54},
}},
{trace.EvGoUnblock, []frame{
{"runtime.chanrecv1", 0},
{"runtime/trace_test.TestTraceSymbolize", 110},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSelect, []frame{
{"runtime.selectgo", 0},
{"runtime/trace_test.TestTraceSymbolize.func6", 59},
}},
{trace.EvGoUnblock, []frame{
{"runtime.selectgo", 0},
{"runtime/trace_test.TestTraceSymbolize", 111},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSync, []frame{
{"sync.(*Mutex).Lock", 0},
{"runtime/trace_test.TestTraceSymbolize.func7", 67},
}},
{trace.EvGoUnblock, []frame{
{"sync.(*Mutex).Unlock", 0},
{"runtime/trace_test.TestTraceSymbolize", 115},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSync, []frame{
{"sync.(*WaitGroup).Wait", 0},
{"runtime/trace_test.TestTraceSymbolize.func8", 73},
}},
{trace.EvGoUnblock, []frame{
{"sync.(*WaitGroup).Add", 0},
{"sync.(*WaitGroup).Done", 0},
{"runtime/trace_test.TestTraceSymbolize", 116},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockCond, []frame{
{"sync.(*Cond).Wait", 0},
{"runtime/trace_test.TestTraceSymbolize.func9", 78},
}},
{trace.EvGoUnblock, []frame{
{"sync.(*Cond).Signal", 0},
{"runtime/trace_test.TestTraceSymbolize", 117},
{"testing.tRunner", 0},
}},
{trace.EvGoSleep, []frame{
{"time.Sleep", 0},
{"runtime/trace_test.TestTraceSymbolize", 108},
{"testing.tRunner", 0},
}},
}
// Stacks for the following events are OS-dependent due to OS-specific code in net package.
if runtime.GOOS != "windows" && runtime.GOOS != "plan9" {
want = append(want, []eventDesc{
{trace.EvGoBlockNet, []frame{
{"net.(*netFD).accept", 0},
{"net.(*TCPListener).AcceptTCP", 0},
{"net.(*TCPListener).Accept", 0},
{"runtime/trace_test.TestTraceSymbolize.func10", 86},
}},
{trace.EvGoSysCall, []frame{
{"syscall.read", 0},
{"syscall.Read", 0},
{"os.(*File).read", 0},
{"os.(*File).Read", 0},
{"runtime/trace_test.TestTraceSymbolize.func11", 101},
}},
}...)
}
matched := make([]bool, len(want))
for _, ev := range events {
wantLoop:
for i, w := range want {
if matched[i] || w.Type != ev.Type || len(w.Stk) != len(ev.Stk) {
continue
}
for fi, f := range ev.Stk {
wf := w.Stk[fi]
if wf.Fn != f.Fn || wf.Line != 0 && wf.Line != f.Line {
continue wantLoop
}
}
matched[i] = true
}
}
for i, m := range matched {
if m {
continue
}
w := want[i]
t.Errorf("did not match event %v at %v:%v", trace.EventDescriptions[w.Type].Name, w.Stk[0].Fn, w.Stk[0].Line)
t.Errorf("seen the following events of this type:")
for _, ev := range events {
if ev.Type != w.Type {
continue
}
for _, f := range ev.Stk {
t.Logf(" %v:%v", f.Fn, f.Line)
}
t.Logf("---")
}
}
}