blob: f427e578dc7d4700af432fa66ddefa3db48242c7 [file] [log] [blame]
// Copyright 2014 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.
package trace_test
import (
"bytes"
"fmt"
"internal/goexperiment"
"internal/testenv"
"internal/trace"
"net"
"os"
"runtime"
. "runtime/trace"
"strings"
"sync"
"testing"
"text/tabwriter"
"time"
)
// 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) {
skipTraceSymbolizeTestIfNecessary(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() { // func1
select {}
}()
go func() { // func2
var c chan int
c <- 0
}()
go func() { // func3
var c chan int
<-c
}()
done1 := make(chan bool)
go func() { // func4
<-done1
}()
done2 := make(chan bool)
go func() { // func5
done2 <- true
}()
c1 := make(chan int)
c2 := make(chan int)
go func() { // func6
select {
case <-c1:
case <-c2:
}
}()
var mu sync.Mutex
mu.Lock()
go func() { // func7
mu.Lock()
mu.Unlock()
}()
var wg sync.WaitGroup
wg.Add(1)
go func() { // func8
wg.Wait()
}()
cv := sync.NewCond(&sync.Mutex{})
go func() { // func9
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() { // func10
c, err := ln.Accept()
if err != nil {
t.Errorf("failed to accept: %v", err)
return
}
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() { // func11
var data [1]byte
rp.Read(data[:])
pipeReadDone <- true
}()
time.Sleep(100 * time.Millisecond)
runtime.GC()
runtime.Gosched()
time.Sleep(100 * 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
oldGoMaxProcs := runtime.GOMAXPROCS(0)
runtime.GOMAXPROCS(oldGoMaxProcs + 1)
Stop()
runtime.GOMAXPROCS(oldGoMaxProcs)
events, _ := parseTrace(t, buf)
// Now check that the stacks are correct.
type eventDesc struct {
Type byte
Stk []frame
}
want := []eventDesc{
{trace.EvGCStart, []frame{
{"runtime.GC", 0},
{"runtime/trace_test.TestTraceSymbolize", 0},
{"testing.tRunner", 0},
}},
{trace.EvGoStart, []frame{
{"runtime/trace_test.TestTraceSymbolize.func1", 0},
}},
{trace.EvGoSched, []frame{
{"runtime/trace_test.TestTraceSymbolize", 112},
{"testing.tRunner", 0},
}},
{trace.EvGoCreate, []frame{
{"runtime/trace_test.TestTraceSymbolize", 41},
{"testing.tRunner", 0},
}},
{trace.EvGoStop, []frame{
{"runtime.block", 0},
{"runtime/trace_test.TestTraceSymbolize.func1", 0},
}},
{trace.EvGoStop, []frame{
{"runtime.chansend1", 0},
{"runtime/trace_test.TestTraceSymbolize.func2", 0},
}},
{trace.EvGoStop, []frame{
{"runtime.chanrecv1", 0},
{"runtime/trace_test.TestTraceSymbolize.func3", 0},
}},
{trace.EvGoBlockRecv, []frame{
{"runtime.chanrecv1", 0},
{"runtime/trace_test.TestTraceSymbolize.func4", 0},
}},
{trace.EvGoUnblock, []frame{
{"runtime.chansend1", 0},
{"runtime/trace_test.TestTraceSymbolize", 114},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSend, []frame{
{"runtime.chansend1", 0},
{"runtime/trace_test.TestTraceSymbolize.func5", 0},
}},
{trace.EvGoUnblock, []frame{
{"runtime.chanrecv1", 0},
{"runtime/trace_test.TestTraceSymbolize", 115},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSelect, []frame{
{"runtime.selectgo", 0},
{"runtime/trace_test.TestTraceSymbolize.func6", 0},
}},
{trace.EvGoUnblock, []frame{
{"runtime.selectgo", 0},
{"runtime/trace_test.TestTraceSymbolize", 116},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSync, []frame{
{"sync.(*Mutex).Lock", 0},
{"runtime/trace_test.TestTraceSymbolize.func7", 0},
}},
{trace.EvGoUnblock, []frame{
{"sync.(*Mutex).Unlock", 0},
{"runtime/trace_test.TestTraceSymbolize", 0},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockSync, []frame{
{"sync.(*WaitGroup).Wait", 0},
{"runtime/trace_test.TestTraceSymbolize.func8", 0},
}},
{trace.EvGoUnblock, []frame{
{"sync.(*WaitGroup).Add", 0},
{"sync.(*WaitGroup).Done", 0},
{"runtime/trace_test.TestTraceSymbolize", 121},
{"testing.tRunner", 0},
}},
{trace.EvGoBlockCond, []frame{
{"sync.(*Cond).Wait", 0},
{"runtime/trace_test.TestTraceSymbolize.func9", 0},
}},
{trace.EvGoUnblock, []frame{
{"sync.(*Cond).Signal", 0},
{"runtime/trace_test.TestTraceSymbolize", 0},
{"testing.tRunner", 0},
}},
{trace.EvGoSleep, []frame{
{"time.Sleep", 0},
{"runtime/trace_test.TestTraceSymbolize", 0},
{"testing.tRunner", 0},
}},
{trace.EvGomaxprocs, []frame{
{"runtime.startTheWorld", 0}, // this is when the current gomaxprocs is logged.
{"runtime.startTheWorldGC", 0},
{"runtime.GOMAXPROCS", 0},
{"runtime/trace_test.TestTraceSymbolize", 0},
{"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{
{"internal/poll.(*FD).Accept", 0},
{"net.(*netFD).accept", 0},
{"net.(*TCPListener).accept", 0},
{"net.(*TCPListener).Accept", 0},
{"runtime/trace_test.TestTraceSymbolize.func10", 0},
}},
{trace.EvGoSysCall, []frame{
{"syscall.read", 0},
{"syscall.Read", 0},
{"internal/poll.ignoringEINTRIO", 0},
{"internal/poll.(*FD).Read", 0},
{"os.(*File).read", 0},
{"os.(*File).Read", 0},
{"runtime/trace_test.TestTraceSymbolize.func11", 0},
}},
}...)
}
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, w := range want {
if matched[i] {
continue
}
seen, n := dumpEventStacks(w.Type, events)
t.Errorf("Did not match event %v with stack\n%s\nSeen %d events of the type\n%s",
trace.EventDescriptions[w.Type].Name, dumpFrames(w.Stk), n, seen)
}
}
func skipTraceSymbolizeTestIfNecessary(t *testing.T) {
testenv.MustHaveGoBuild(t)
if goexperiment.ExecTracer2 {
// An equivalent test exists in internal/trace/v2.
t.Skip("skipping because this test is incompatible with the new tracer")
}
if IsEnabled() {
t.Skip("skipping because -test.trace is set")
}
}
func dumpEventStacks(typ byte, events []*trace.Event) ([]byte, int) {
matched := 0
o := new(bytes.Buffer)
tw := tabwriter.NewWriter(o, 0, 8, 0, '\t', 0)
for _, ev := range events {
if ev.Type != typ {
continue
}
matched++
fmt.Fprintf(tw, "Offset %d\n", ev.Off)
for _, f := range ev.Stk {
fname := f.File
if idx := strings.Index(fname, "/go/src/"); idx > 0 {
fname = fname[idx:]
}
fmt.Fprintf(tw, " %v\t%s:%d\n", f.Fn, fname, f.Line)
}
}
tw.Flush()
return o.Bytes(), matched
}
type frame struct {
Fn string
Line int
}
func dumpFrames(frames []frame) []byte {
o := new(bytes.Buffer)
tw := tabwriter.NewWriter(o, 0, 8, 0, '\t', 0)
for _, f := range frames {
fmt.Fprintf(tw, " %v\t :%d\n", f.Fn, f.Line)
}
tw.Flush()
return o.Bytes()
}