mirror of
https://github.com/golang/go
synced 2024-11-20 02:24:43 -07:00
67faca7d9c
This change breaks out most of the atomics functions in the runtime into package runtime/internal/atomic. It adds some basic support in the toolchain for runtime packages, and also modifies linux/arm atomics to remove the dependency on the runtime's mutex. The mutexes have been replaced with spinlocks. all trybots are happy! In addition to the trybots, I've tested on the darwin/arm64 builder, on the darwin/arm builder, and on a ppc64le machine. Change-Id: I6698c8e3cf3834f55ce5824059f44d00dc8e3c2f Reviewed-on: https://go-review.googlesource.com/14204 Run-TryBot: Michael Matloob <matloob@golang.org> Reviewed-by: Russ Cox <rsc@golang.org>
59 lines
1.3 KiB
Go
59 lines
1.3 KiB
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
|
|
|
|
import (
|
|
"runtime/internal/atomic"
|
|
_ "unsafe" // for go:linkname
|
|
)
|
|
|
|
//go:generate go run wincallback.go
|
|
//go:generate go run mkduff.go
|
|
//go:generate go run mkfastlog2table.go
|
|
|
|
var ticks struct {
|
|
lock mutex
|
|
pad uint32 // ensure 8-byte alignment of val on 386
|
|
val uint64
|
|
}
|
|
|
|
var tls0 [8]uintptr // available storage for m0's TLS; not necessarily used; opaque to GC
|
|
|
|
// Note: Called by runtime/pprof in addition to runtime code.
|
|
func tickspersecond() int64 {
|
|
r := int64(atomic.Load64(&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++
|
|
}
|
|
atomic.Store64(&ticks.val, uint64(r))
|
|
}
|
|
unlock(&ticks.lock)
|
|
return r
|
|
}
|
|
|
|
var envs []string
|
|
var argslice []string
|
|
|
|
//go:linkname syscall_runtime_envs syscall.runtime_envs
|
|
func syscall_runtime_envs() []string { return append([]string{}, envs...) }
|
|
|
|
//go:linkname os_runtime_args os.runtime_args
|
|
func os_runtime_args() []string { return append([]string{}, argslice...) }
|