mirror of
https://github.com/golang/go
synced 2024-10-07 11:11:21 -06:00
44753479c6
LGTM=iant, khr, rlh R=khr, iant, bradfitz, rlh CC=dvyukov, golang-codereviews https://golang.org/cl/142030044
42 lines
778 B
Go
42 lines
778 B
Go
// Copyright 2009 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.
|
|
|
|
package runtime
|
|
|
|
var ticks struct {
|
|
lock mutex
|
|
val uint64
|
|
}
|
|
|
|
// Note: Called by runtime/pprof in addition to runtime code.
|
|
func tickspersecond() int64 {
|
|
r := int64(atomicload64(&ticks.val))
|
|
if r != 0 {
|
|
return r
|
|
}
|
|
lock(&ticks.lock)
|
|
r = int64(ticks.val)
|
|
if r == 0 {
|
|
t0 := nanotime()
|
|
c0 := cputicks()
|
|
usleep(100 * 1000)
|
|
t1 := nanotime()
|
|
c1 := cputicks()
|
|
if t1 == t0 {
|
|
t1++
|
|
}
|
|
r = (c1 - c0) * 1000 * 1000 * 1000 / (t1 - t0)
|
|
if r == 0 {
|
|
r++
|
|
}
|
|
atomicstore64(&ticks.val, uint64(r))
|
|
}
|
|
unlock(&ticks.lock)
|
|
return r
|
|
}
|
|
|
|
func makeStringSlice(n int) []string {
|
|
return make([]string, n)
|
|
}
|