// 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" "internal/testenv" "internal/trace" "net" "os" "runtime" . "runtime/trace" "sync" "testing" "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) { 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.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() { 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 Stop() events, _ := parseTrace(t, buf) // 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", 107}, {"testing.tRunner", 0}, }}, {trace.EvGoStart, []frame{ {"runtime/trace_test.TestTraceSymbolize.func1", 37}, }}, {trace.EvGoSched, []frame{ {"runtime/trace_test.TestTraceSymbolize", 108}, {"testing.tRunner", 0}, }}, {trace.EvGoCreate, []frame{ {"runtime/trace_test.TestTraceSymbolize", 37}, {"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", 110}, {"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", 111}, {"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", 112}, {"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", 116}, {"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", 117}, {"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", 118}, {"testing.tRunner", 0}, }}, {trace.EvGoSleep, []frame{ {"time.Sleep", 0}, {"runtime/trace_test.TestTraceSymbolize", 109}, {"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", 86}, }}, {trace.EvGoSysCall, []frame{ {"syscall.read", 0}, {"syscall.Read", 0}, {"internal/poll.(*FD).Read", 0}, {"os.(*File).read", 0}, {"os.(*File).Read", 0}, {"runtime/trace_test.TestTraceSymbolize.func11", 102}, }}, }...) } 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 :: %s:%v", f.Fn, f.File, f.Line) } t.Logf("---") } t.Logf("======") } }