github.com/m10x/go/src@v0.0.0-20220112094212-ba61592315da/runtime/pprof/rusage_test.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  //go:build darwin || freebsd || linux || netbsd || openbsd
     6  
     7  package pprof
     8  
     9  import (
    10  	"syscall"
    11  	"time"
    12  )
    13  
    14  func init() {
    15  	diffCPUTimeImpl = diffCPUTimeRUsage
    16  }
    17  
    18  func diffCPUTimeRUsage(f func()) time.Duration {
    19  	ok := true
    20  	var before, after syscall.Rusage
    21  
    22  	err := syscall.Getrusage(syscall.RUSAGE_SELF, &before)
    23  	if err != nil {
    24  		ok = false
    25  	}
    26  
    27  	f()
    28  
    29  	err = syscall.Getrusage(syscall.RUSAGE_SELF, &after)
    30  	if err != nil {
    31  		ok = false
    32  	}
    33  
    34  	if !ok {
    35  		return 0
    36  	}
    37  
    38  	return time.Duration((after.Utime.Nano() + after.Stime.Nano()) - (before.Utime.Nano() + before.Stime.Nano()))
    39  }