github.com/x04/go/src@v0.0.0-20200202162449-3d481ceb3525/runtime/testdata/testprog/vdso.go (about)

     1  // Copyright 2019 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Invoke signal hander in the VDSO context (see issue 32912).
     6  
     7  package main
     8  
     9  import (
    10  	"github.com/x04/go/src/fmt"
    11  	"github.com/x04/go/src/io/ioutil"
    12  	"github.com/x04/go/src/os"
    13  	"github.com/x04/go/src/runtime/pprof"
    14  	"github.com/x04/go/src/time"
    15  )
    16  
    17  func init() {
    18  	register("SignalInVDSO", signalInVDSO)
    19  }
    20  
    21  func signalInVDSO() {
    22  	f, err := ioutil.TempFile("", "timeprofnow")
    23  	if err != nil {
    24  		fmt.Fprintln(os.Stderr, err)
    25  		os.Exit(2)
    26  	}
    27  
    28  	if err := pprof.StartCPUProfile(f); err != nil {
    29  		fmt.Fprintln(os.Stderr, err)
    30  		os.Exit(2)
    31  	}
    32  
    33  	t0 := time.Now()
    34  	t1 := t0
    35  	// We should get a profiling signal 100 times a second,
    36  	// so running for 1 second should be sufficient.
    37  	for t1.Sub(t0) < time.Second {
    38  		t1 = time.Now()
    39  	}
    40  
    41  	pprof.StopCPUProfile()
    42  
    43  	name := f.Name()
    44  	if err := f.Close(); err != nil {
    45  		fmt.Fprintln(os.Stderr, err)
    46  		os.Exit(2)
    47  	}
    48  
    49  	if err := os.Remove(name); err != nil {
    50  		fmt.Fprintln(os.Stderr, err)
    51  		os.Exit(2)
    52  	}
    53  
    54  	fmt.Println("success")
    55  }