| // Copyright 2019 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. | 
 |  | 
 | // Invoke signal hander in the VDSO context (see issue 32912). | 
 |  | 
 | package main | 
 |  | 
 | import ( | 
 | 	"fmt" | 
 | 	"os" | 
 | 	"runtime/pprof" | 
 | 	"time" | 
 | ) | 
 |  | 
 | func init() { | 
 | 	register("SignalInVDSO", signalInVDSO) | 
 | } | 
 |  | 
 | func signalInVDSO() { | 
 | 	f, err := os.CreateTemp("", "timeprofnow") | 
 | 	if err != nil { | 
 | 		fmt.Fprintln(os.Stderr, err) | 
 | 		os.Exit(2) | 
 | 	} | 
 |  | 
 | 	if err := pprof.StartCPUProfile(f); err != nil { | 
 | 		fmt.Fprintln(os.Stderr, err) | 
 | 		os.Exit(2) | 
 | 	} | 
 |  | 
 | 	t0 := time.Now() | 
 | 	t1 := t0 | 
 | 	// We should get a profiling signal 100 times a second, | 
 | 	// so running for 1 second should be sufficient. | 
 | 	for t1.Sub(t0) < time.Second { | 
 | 		t1 = time.Now() | 
 | 	} | 
 |  | 
 | 	pprof.StopCPUProfile() | 
 |  | 
 | 	name := f.Name() | 
 | 	if err := f.Close(); err != nil { | 
 | 		fmt.Fprintln(os.Stderr, err) | 
 | 		os.Exit(2) | 
 | 	} | 
 |  | 
 | 	if err := os.Remove(name); err != nil { | 
 | 		fmt.Fprintln(os.Stderr, err) | 
 | 		os.Exit(2) | 
 | 	} | 
 |  | 
 | 	fmt.Println("success") | 
 | } |