func TestMutexProfile(t *testing.T) {
old := runtime.SetMutexProfileFraction(1)
defer runtime.SetMutexProfileFraction(old)
if old != 0 {
t.Fatalf("need MutexProfileRate 0, got %d", old)
}
blockMutex()
var w bytes.Buffer
Lookup("mutex").WriteTo(&w, 1)
prof := w.String()
if !strings.HasPrefix(prof, "--- mutex:\ncycles/second=") {
t.Errorf("Bad profile header:\n%v", prof)
}
prof = strings.Trim(prof, "\n")
lines := strings.Split(prof, "\n")
if len(lines) != 6 {
t.Errorf("expected 6 lines, got %d %q\n%s", len(lines), prof, prof)
}
if len(lines) < 6 {
return
}
// checking that the line is like "35258904 1 @ 0x48288d 0x47cd28 0x458931"
r2 := `^\d+ 1 @(?: 0x[[:xdigit:]]+)+`
//r2 := "^[0-9]+ 1 @ 0x[0-9a-f x]+$"
if ok, err := regexp.MatchString(r2, lines[3]); err != nil || !ok {
t.Errorf("%q didn't match %q", lines[3], r2)
}
r3 := "^#.*runtime/pprof_test.blockMutex.*$"
if ok, err := regexp.MatchString(r3, lines[5]); err != nil || !ok {
t.Errorf("%q didn't match %q", lines[5], r3)
}
}
func TestMutex(t *testing.T) {
if n := runtime.SetMutexProfileFraction(1); n != 0 {
t.Logf("got mutexrate %d expected 0", n)
}
defer runtime.SetMutexProfileFraction(0)
m := new(Mutex)
c := make(chan bool)
for i := 0; i < 10; i++ {
go HammerMutex(m, 1000, c)
}
for i := 0; i < 10; i++ {
<-c
}
}
// writeMutex writes the current mutex profile to w.
func writeMutex(w io.Writer, debug int) error {
// TODO(pjw): too much common code with writeBlock. FIX!
var p []runtime.BlockProfileRecord
n, ok := runtime.MutexProfile(nil)
for {
p = make([]runtime.BlockProfileRecord, n+50)
n, ok = runtime.MutexProfile(p)
if ok {
p = p[:n]
break
}
}
sort.Slice(p, func(i, j int) bool { return p[i].Cycles > p[j].Cycles })
b := bufio.NewWriter(w)
var tw *tabwriter.Writer
w = b
if debug > 0 {
tw = tabwriter.NewWriter(w, 1, 8, 1, '\t', 0)
w = tw
}
fmt.Fprintf(w, "--- mutex:\n")
fmt.Fprintf(w, "cycles/second=%v\n", runtime_cyclesPerSecond())
fmt.Fprintf(w, "sampling period=%d\n", runtime.SetMutexProfileFraction(-1))
for i := range p {
r := &p[i]
fmt.Fprintf(w, "%v %v @", r.Cycles, r.Count)
for _, pc := range r.Stack() {
fmt.Fprintf(w, " %#x", pc)
}
fmt.Fprint(w, "\n")
if debug > 0 {
printStackRecord(w, r.Stack(), true)
}
}
if tw != nil {
tw.Flush()
}
return b.Flush()
}
// before runs before all testing.
func (m *M) before() {
if *memProfileRate > 0 {
runtime.MemProfileRate = *memProfileRate
}
if *cpuProfile != "" {
f, err := os.Create(toOutputDir(*cpuProfile))
if err != nil {
fmt.Fprintf(os.Stderr, "testing: %s", err)
return
}
if err := m.deps.StartCPUProfile(f); err != nil {
fmt.Fprintf(os.Stderr, "testing: can't start cpu profile: %s", err)
f.Close()
return
}
// Could save f so after can call f.Close; not worth the effort.
}
if *traceFile != "" {
f, err := os.Create(toOutputDir(*traceFile))
if err != nil {
fmt.Fprintf(os.Stderr, "testing: %s", err)
return
}
if err := trace.Start(f); err != nil {
fmt.Fprintf(os.Stderr, "testing: can't start tracing: %s", err)
f.Close()
return
}
// Could save f so after can call f.Close; not worth the effort.
}
if *blockProfile != "" && *blockProfileRate >= 0 {
runtime.SetBlockProfileRate(*blockProfileRate)
}
if *mutexProfile != "" && *mutexProfileFraction >= 0 {
runtime.SetMutexProfileFraction(*mutexProfileFraction)
}
if *coverProfile != "" && cover.Mode == "" {
fmt.Fprintf(os.Stderr, "testing: cannot use -test.coverprofile because test binary was not built with coverage enabled\n")
os.Exit(2)
}
}