atomic - The Go Programming Language

Golang

Package atomic

import "sync/atomic"
Overview
Index

Overview ?

Overview ?

Package atomic provides low-level atomic memory primitives useful for implementing synchronization algorithms.

These functions require great care to be used correctly. Except for special, low-level applications, synchronization is better done with channels or the facilities of the sync package. Share memory by communicating; don't communicate by sharing memory.

The compare-and-swap operation, implemented by the CompareAndSwapT functions, is the atomic equivalent of:

if *val == old {
	*val = new
	return true
}
return false

Index

func AddInt32(val *int32, delta int32) (new int32)
func AddInt64(val *int64, delta int64) (new int64)
func AddUint32(val *uint32, delta uint32) (new uint32)
func AddUint64(val *uint64, delta uint64) (new uint64)
func AddUintptr(val *uintptr, delta uintptr) (new uintptr)
func CompareAndSwapInt32(val *int32, old, new int32) (swapped bool)
func CompareAndSwapInt64(val *int64, old, new int64) (swapped bool)
func CompareAndSwapPointer(val *unsafe.Pointer, old, new unsafe.Pointer) (swapped bool)
func CompareAndSwapUint32(val *uint32, old, new uint32) (swapped bool)
func CompareAndSwapUint64(val *uint64, old, new uint64) (swapped bool)
func CompareAndSwapUintptr(val *uintptr, old, new uintptr) (swapped bool)
func LoadInt32(addr *int32) (val int32)
func LoadInt64(addr *int64) (val int64)
func LoadPointer(addr *unsafe.Pointer) (val unsafe.Pointer)
func LoadUint32(addr *uint32) (val uint32)
func LoadUint64(addr *uint64) (val uint64)
func LoadUintptr(addr *uintptr) (val uintptr)
func StoreInt32(addr *int32, val int32)
func StoreInt64(addr *int64, val int64)
func StorePointer(addr *unsafe.Pointer, val unsafe.Pointer)
func StoreUint32(addr *uint32, val uint32)
func StoreUint64(addr *uint64, val uint64)
func StoreUintptr(addr *uintptr, val uintptr)
Bugs

Package files

doc.go

func AddInt32

func AddInt32(val *int32, delta int32) (new int32)

AddInt32 atomically adds delta to *val and returns the new value.

func AddInt64

func AddInt64(val *int64, delta int64) (new int64)

AddInt64 atomically adds delta to *val and returns the new value.

func AddUint32

func AddUint32(val *uint32, delta uint32) (new uint32)

AddUint32 atomically adds delta to *val and returns the new value.

func AddUint64

func AddUint64(val *uint64, delta uint64) (new uint64)

AddUint64 atomically adds delta to *val and returns the new value.

func AddUintptr

func AddUintptr(val *uintptr, delta uintptr) (new uintptr)

AddUintptr atomically adds delta to *val and returns the new value.

func CompareAndSwapInt32

func CompareAndSwapInt32(val *int32, old, new int32) (swapped bool)

CompareAndSwapInt32 executes the compare-and-swap operation for an int32 value.

func CompareAndSwapInt64

func CompareAndSwapInt64(val *int64, old, new int64) (swapped bool)

CompareAndSwapInt64 executes the compare-and-swap operation for an int64 value.

func CompareAndSwapPointer

func CompareAndSwapPointer(val *unsafe.Pointer, old, new unsafe.Pointer) (swapped bool)

CompareAndSwapPointer executes the compare-and-swap operation for a unsafe.Pointer value.

func CompareAndSwapUint32

func CompareAndSwapUint32(val *uint32, old, new uint32) (swapped bool)

CompareAndSwapUint32 executes the compare-and-swap operation for a uint32 value.

func CompareAndSwapUint64

func CompareAndSwapUint64(val *uint64, old, new uint64) (swapped bool)

CompareAndSwapUint64 executes the compare-and-swap operation for a uint64 value.

func CompareAndSwapUintptr

func CompareAndSwapUintptr(val *uintptr, old, new uintptr) (swapped bool)

CompareAndSwapUintptr executes the compare-and-swap operation for a uintptr value.

func LoadInt32

func LoadInt32(addr *int32) (val int32)

LoadInt32 atomically loads *addr.

func LoadInt64

func LoadInt64(addr *int64) (val int64)

LoadInt64 atomically loads *addr.

func LoadPointer

func LoadPointer(addr *unsafe.Pointer) (val unsafe.Pointer)

LoadPointer atomically loads *addr.

func LoadUint32

func LoadUint32(addr *uint32) (val uint32)

LoadUint32 atomically loads *addr.

func LoadUint64

func LoadUint64(addr *uint64) (val uint64)

LoadUint64 atomically loads *addr.

func LoadUintptr

func LoadUintptr(addr *uintptr) (val uintptr)

LoadUintptr atomically loads *addr.

func StoreInt32

func StoreInt32(addr *int32, val int32)

StoreInt32 atomically stores val into *addr.

func StoreInt64

func StoreInt64(addr *int64, val int64)

StoreInt64 atomically stores val into *addr.

func StorePointer

func StorePointer(addr *unsafe.Pointer, val unsafe.Pointer)

StorePointer atomically stores val into *addr.

func StoreUint32

func StoreUint32(addr *uint32, val uint32)

StoreUint32 atomically stores val into *addr.

func StoreUint64

func StoreUint64(addr *uint64, val uint64)

StoreUint64 atomically stores val into *addr.

func StoreUintptr

func StoreUintptr(addr *uintptr, val uintptr)

StoreUintptr atomically stores val into *addr.

Bugs

On ARM, the 64-bit functions use instructions unavailable before ARM 11.

On x86-32, the 64-bit functions use instructions unavailable before the Pentium MMX.