1 // Copyright 2016 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 // +build windows,race 6 7 package race_test 8 9 import ( 10 "sync/atomic" 11 "syscall" 12 "testing" 13 "unsafe" 14 ) 15 16 func TestAtomicMmap(t *testing.T) { 17 // Test that atomic operations work on "external" memory. Previously they crashed (#16206). 18 // Also do a sanity correctness check: under race detector atomic operations 19 // are implemented inside of race runtime. 20 kernel32 := syscall.NewLazyDLL("kernel32.dll") 21 VirtualAlloc := kernel32.NewProc("VirtualAlloc") 22 VirtualFree := kernel32.NewProc("VirtualFree") 23 const ( 24 MEM_COMMIT = 0x00001000 25 MEM_RESERVE = 0x00002000 26 MEM_RELEASE = 0x8000 27 PAGE_READWRITE = 0x04 28 ) 29 mem, _, err := syscall.Syscall6(VirtualAlloc.Addr(), 4, 0, 1<<20, MEM_COMMIT|MEM_RESERVE, PAGE_READWRITE, 0, 0) 30 if err != 0 { 31 t.Fatalf("VirtualAlloc failed: %v", err) 32 } 33 defer syscall.Syscall(VirtualFree.Addr(), 3, mem, 1<<20, MEM_RELEASE) 34 a := (*uint64)(unsafe.Pointer(mem)) 35 if *a != 0 { 36 t.Fatalf("bad atomic value: %v, want 0", *a) 37 } 38 atomic.AddUint64(a, 1) 39 if *a != 1 { 40 t.Fatalf("bad atomic value: %v, want 1", *a) 41 } 42 atomic.AddUint64(a, 1) 43 if *a != 2 { 44 t.Fatalf("bad atomic value: %v, want 2", *a) 45 } 46 } 47
