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// Copyright 2011 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_test
import (
"runtime"
"testing"
"time"
"unsafe"
)
type Tintptr *int // assignable to *int
type Tint int // *Tint implements Tinter, interface{}
func (t *Tint) m() {}
type Tinter interface {
m()
}
func TestFinalizerType(t *testing.T) {
if runtime.GOARCH != "amd64" {
t.Skipf("Skipping on non-amd64 machine")
}
ch := make(chan bool, 10)
finalize := func(x *int) {
if *x != 97531 {
t.Errorf("finalizer %d, want %d", *x, 97531)
}
ch <- true
}
var finalizerTests = []struct {
convert func(*int) interface{}
finalizer interface{}
}{
{func(x *int) interface{} { return x }, func(v *int) { finalize(v) }},
{func(x *int) interface{} { return Tintptr(x) }, func(v Tintptr) { finalize(v) }},
{func(x *int) interface{} { return Tintptr(x) }, func(v *int) { finalize(v) }},
{func(x *int) interface{} { return (*Tint)(x) }, func(v *Tint) { finalize((*int)(v)) }},
{func(x *int) interface{} { return (*Tint)(x) }, func(v Tinter) { finalize((*int)(v.(*Tint))) }},
}
for _, tt := range finalizerTests {
done := make(chan bool, 1)
go func() {
v := new(int)
*v = 97531
runtime.SetFinalizer(tt.convert(v), tt.finalizer)
v = nil
done <- true
}()
<-done
runtime.GC()
select {
case <-ch:
case <-time.After(time.Second * 4):
t.Errorf("finalizer for type %T didn't run", tt.finalizer)
}
}
}
type bigValue struct {
fill uint64
it bool
up string
}
func TestFinalizerInterfaceBig(t *testing.T) {
if runtime.GOARCH != "amd64" {
t.Skipf("Skipping on non-amd64 machine")
}
ch := make(chan bool)
done := make(chan bool, 1)
go func() {
v := &bigValue{0xDEADBEEFDEADBEEF, true, "It matters not how strait the gate"}
old := *v
runtime.SetFinalizer(v, func(v interface{}) {
i, ok := v.(*bigValue)
if !ok {
t.Errorf("finalizer called with type %T, want *bigValue", v)
}
if *i != old {
t.Errorf("finalizer called with %+v, want %+v", *i, old)
}
close(ch)
})
v = nil
done <- true
}()
<-done
runtime.GC()
select {
case <-ch:
case <-time.After(4 * time.Second):
t.Errorf("finalizer for type *bigValue didn't run")
}
}
func fin(v *int) {
}
// Verify we don't crash at least. golang.org/issue/6857
func TestFinalizerZeroSizedStruct(t *testing.T) {
type Z struct{}
z := new(Z)
runtime.SetFinalizer(z, func(*Z) {})
}
func BenchmarkFinalizer(b *testing.B) {
const Batch = 1000
b.RunParallel(func(pb *testing.PB) {
var data [Batch]*int
for i := 0; i < Batch; i++ {
data[i] = new(int)
}
for pb.Next() {
for i := 0; i < Batch; i++ {
runtime.SetFinalizer(data[i], fin)
}
for i := 0; i < Batch; i++ {
runtime.SetFinalizer(data[i], nil)
}
}
})
}
func BenchmarkFinalizerRun(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
v := new(int)
runtime.SetFinalizer(v, fin)
}
})
}
// One chunk must be exactly one sizeclass in size.
// It should be a sizeclass not used much by others, so we
// have a greater chance of finding adjacent ones.
// size class 19: 320 byte objects, 25 per page, 1 page alloc at a time
const objsize = 320
type objtype [objsize]byte
func adjChunks() (*objtype, *objtype) {
var s []*objtype
for {
c := new(objtype)
for _, d := range s {
if uintptr(unsafe.Pointer(c))+unsafe.Sizeof(*c) == uintptr(unsafe.Pointer(d)) {
return c, d
}
if uintptr(unsafe.Pointer(d))+unsafe.Sizeof(*c) == uintptr(unsafe.Pointer(c)) {
return d, c
}
}
s = append(s, c)
}
}
// Make sure an empty slice on the stack doesn't pin the next object in memory.
func TestEmptySlice(t *testing.T) {
if true { // disable until bug 7564 is fixed.
return
}
x, y := adjChunks()
// the pointer inside xs points to y.
xs := x[objsize:] // change objsize to objsize-1 and the test passes
fin := make(chan bool, 1)
runtime.SetFinalizer(y, func(z *objtype) { fin <- true })
runtime.GC()
select {
case <-fin:
case <-time.After(4 * time.Second):
t.Errorf("finalizer of next object in memory didn't run")
}
xsglobal = xs // keep empty slice alive until here
}
var xsglobal []byte
func adjStringChunk() (string, *objtype) {
b := make([]byte, objsize)
for {
s := string(b)
t := new(objtype)
p := *(*uintptr)(unsafe.Pointer(&s))
q := uintptr(unsafe.Pointer(t))
if p+objsize == q {
return s, t
}
}
}
// Make sure an empty string on the stack doesn't pin the next object in memory.
func TestEmptyString(t *testing.T) {
x, y := adjStringChunk()
ss := x[objsize:] // change objsize to objsize-1 and the test passes
fin := make(chan bool, 1)
// set finalizer on string contents of y
runtime.SetFinalizer(y, func(z *objtype) { fin <- true })
runtime.GC()
select {
case <-fin:
case <-time.After(4 * time.Second):
t.Errorf("finalizer of next string in memory didn't run")
}
ssglobal = ss // keep 0-length string live until here
}
var ssglobal string
// Test for issue 7656.
func TestFinalizerOnGlobal(t *testing.T) {
runtime.SetFinalizer(Foo1, func(p *Object1) {})
runtime.SetFinalizer(Foo2, func(p *Object2) {})
runtime.SetFinalizer(Foo1, nil)
runtime.SetFinalizer(Foo2, nil)
}
type Object1 struct {
Something []byte
}
type Object2 struct {
Something byte
}
var (
Foo2 = &Object2{}
Foo1 = &Object1{}
)
|
