1 files changed, 103 insertions, 0 deletions
diff --git a/src/cmd/trace/trace_unix_test.go b/src/cmd/trace/trace_unix_test.go
new file mode 100644
index 0000000..c569b40
--- /dev/null
+++ b/src/cmd/trace/trace_unix_test.go
@@ -0,0 +1,103 @@
+// Copyright 2017 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.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package main
+
+import (
+	"bytes"
+	"cmd/internal/traceviewer"
+	traceparser "internal/trace"
+	"io"
+	"runtime"
+	"runtime/trace"
+	"sync"
+	"syscall"
+	"testing"
+	"time"
+)
+
+// TestGoroutineInSyscall tests threads for timer goroutines
+// that preexisted when the tracing started were not counted
+// as threads in syscall. See golang.org/issues/22574.
+func TestGoroutineInSyscall(t *testing.T) {
+	// Start one goroutine blocked in syscall.
+	//
+	// TODO: syscall.Pipe used to cause the goroutine to
+	// remain blocked in syscall is not portable. Replace
+	// it with a more portable way so this test can run
+	// on non-unix architecture e.g. Windows.
+	var p [2]int
+	if err := syscall.Pipe(p[:]); err != nil {
+		t.Fatalf("failed to create pipe: %v", err)
+	}
+
+	var wg sync.WaitGroup
+	defer func() {
+		syscall.Write(p[1], []byte("a"))
+		wg.Wait()
+
+		syscall.Close(p[0])
+		syscall.Close(p[1])
+	}()
+	wg.Add(1)
+	go func() {
+		var tmp [1]byte
+		syscall.Read(p[0], tmp[:])
+		wg.Done()
+	}()
+
+	// Start multiple timer goroutines.
+	allTimers := make([]*time.Timer, 2*runtime.GOMAXPROCS(0))
+	defer func() {
+		for _, timer := range allTimers {
+			timer.Stop()
+		}
+	}()
+
+	var timerSetup sync.WaitGroup
+	for i := range allTimers {
+		timerSetup.Add(1)
+		go func(i int) {
+			defer timerSetup.Done()
+			allTimers[i] = time.AfterFunc(time.Hour, nil)
+		}(i)
+	}
+	timerSetup.Wait()
+
+	// Collect and parse trace.
+	buf := new(bytes.Buffer)
+	if err := trace.Start(buf); err != nil {
+		t.Fatalf("failed to start tracing: %v", err)
+	}
+	trace.Stop()
+
+	res, err := traceparser.Parse(buf, "")
+	if err == traceparser.ErrTimeOrder {
+		t.Skipf("skipping due to golang.org/issue/16755 (timestamps are unreliable): %v", err)
+	} else if err != nil {
+		t.Fatalf("failed to parse trace: %v", err)
+	}
+
+	// Check only one thread for the pipe read goroutine is
+	// considered in-syscall.
+	c := viewerDataTraceConsumer(io.Discard, 0, 1<<63-1)
+	c.consumeViewerEvent = func(ev *traceviewer.Event, _ bool) {
+		if ev.Name == "Threads" {
+			arg := ev.Arg.(*threadCountersArg)
+			if arg.InSyscall > 1 {
+				t.Errorf("%d threads in syscall at time %v; want less than 1 thread in syscall", arg.InSyscall, ev.Time)
+			}
+		}
+	}
+
+	param := &traceParams{
+		parsed:  res,
+		endTime: int64(1<<63 - 1),
+	}
+	if err := generateTrace(param, c); err != nil {
+		t.Fatalf("failed to generate ViewerData: %v", err)
+	}
+}