Fixed GC bug

This commit is contained in:
Dmitry Stogov 2008-03-14 13:21:04 +00:00
parent 8f6b35ccd3
commit e1a28ee945
3 changed files with 116 additions and 29 deletions

31
Zend/tests/gc_028.phpt Normal file
View File

@ -0,0 +1,31 @@
--TEST--
GC 028: GC and destructors
--FILE--
<?php
class Foo {
public $bar;
function __destruct() {
if ($this->bar !== null) {
unset($this->bar);
}
}
}
class Bar {
public $foo;
function __destruct() {
if ($this->foo !== null) {
unset($this->foo);
}
}
}
$foo = new Foo();
$bar = new Bar();
$foo->bar = $bar;
$bar->foo = $foo;
unset($foo);
unset($bar);
var_dump(gc_collect_cycles());
?>
--EXPECT--
int(2)

View File

@ -55,6 +55,7 @@ static void gc_globals_ctor_ex(zend_gc_globals *gc_globals TSRMLS_DC)
gc_globals->roots.prev = NULL;
gc_globals->unused = NULL;
gc_globals->zval_to_free = NULL;
gc_globals->free_list = NULL;
gc_globals->gc_runs = 0;
gc_globals->collected = 0;
@ -136,6 +137,19 @@ ZEND_API void gc_init(TSRMLS_D)
ZEND_API void gc_zval_possible_root(zval *zv TSRMLS_DC)
{
if (UNEXPECTED(GC_G(free_list) != NULL &&
GC_ZVAL_ADDRESS(zv) != NULL &&
GC_ZVAL_GET_COLOR(zv) == GC_BLACK)) {
zval_gc_info **p = &GC_G(free_list);
while (*p != NULL) {
if (*p == (zval_gc_info*)zv) {
return;
}
p = &(*p)->u.next;
}
}
if (zv->type == IS_OBJECT) {
GC_ZOBJ_CHECK_POSSIBLE_ROOT(zv);
return;
@ -235,6 +249,28 @@ ZEND_API void gc_zobj_possible_root(zval *zv TSRMLS_DC)
}
}
ZEND_API void _gc_remove_zval_from_buffer(zval *zv)
{
gc_root_buffer* root_buffer = GC_ADDRESS(((zval_gc_info*)zv)->u.buffered);
TSRMLS_FETCH();
if (UNEXPECTED(GC_G(free_list) != NULL &&
GC_ZVAL_GET_COLOR(zv) == GC_BLACK)) {
zval_gc_info **p = &GC_G(free_list);
while (*p != NULL) {
if (*p == (zval_gc_info*)zv) {
*p = (*p)->u.next;
return;
}
p = &(*p)->u.next;
}
}
GC_BENCH_INC(zval_remove_from_buffer);
GC_REMOVE_FROM_BUFFER(root_buffer);
((zval_gc_info*)zv)->u.buffered = NULL;
}
static void zobj_scan_black(struct _store_object *obj, zval *pz TSRMLS_DC)
{
GC_SET_BLACK(obj->buffered);
@ -371,7 +407,6 @@ static int zval_scan(zval *pz TSRMLS_DC)
zval_scan_black(pz TSRMLS_CC);
} else {
GC_ZVAL_SET_COLOR(pz, GC_WHITE);
if (Z_TYPE_P(pz) == IS_OBJECT) {
zobj_scan(pz TSRMLS_CC);
} else if (Z_TYPE_P(pz) == IS_ARRAY) {
@ -435,17 +470,22 @@ static void zval_collect_white(zval *pz TSRMLS_DC)
if (Z_TYPE_P(pz) == IS_OBJECT) {
zobj_collect_white(pz TSRMLS_CC);
if (EXPECTED(EG(objects_store).object_buckets[Z_OBJ_HANDLE_P(pz)].valid &&
Z_OBJ_HANDLER_P(pz, get_properties) != NULL)) {
Z_OBJPROP_P(pz)->pDestructor = NULL;
}
} else {
if (Z_TYPE_P(pz) == IS_ARRAY) {
if (Z_ARRVAL_P(pz) == &EG(symbol_table)) {
return;
}
// if (Z_ARRVAL_P(pz) == &EG(symbol_table)) {
// return;
// }
zend_hash_apply(Z_ARRVAL_P(pz), (apply_func_t) children_collect_white TSRMLS_CC);
Z_ARRVAL_P(pz)->pDestructor = NULL;
}
/* restore refcount */
pz->refcount__gc++;
}
/* restore refcount and put into list to free */
pz->refcount__gc++;
((zval_gc_info*)pz)->u.next = GC_G(zval_to_free);
GC_G(zval_to_free) = (zval_gc_info*)pz;
}
@ -453,6 +493,9 @@ static void zval_collect_white(zval *pz TSRMLS_DC)
static int children_collect_white(zval **pz TSRMLS_DC)
{
if (Z_TYPE_PP(pz) != IS_ARRAY || Z_ARRVAL_PP(pz) != &EG(symbol_table)) {
(*pz)->refcount__gc++;
}
zval_collect_white(*pz TSRMLS_CC);
return 0;
}
@ -486,7 +529,7 @@ ZEND_API int gc_collect_cycles(TSRMLS_D)
int count = 0;
if (GC_G(roots).next != &GC_G(roots)) {
zval_gc_info *p, *q;
zval_gc_info *p, *q, *orig_free_list;
if (GC_G(gc_active)) {
return 0;
@ -497,35 +540,53 @@ ZEND_API int gc_collect_cycles(TSRMLS_D)
gc_mark_roots(TSRMLS_C);
gc_scan_roots(TSRMLS_C);
gc_collect_roots(TSRMLS_C);
orig_free_list = GC_G(free_list);
p = GC_G(free_list) = GC_G(zval_to_free);
GC_G(zval_to_free) = NULL;
GC_G(gc_active) = 0;
p = GC_G(zval_to_free);
GC_G(zval_to_free) = NULL;
/* First call destructors */
while (p) {
if (Z_TYPE(p->z) == IS_OBJECT) {
if (EG(objects_store).object_buckets &&
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].valid &&
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].bucket.obj.refcount <= 0 &&
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].bucket.obj.dtor &&
!EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].destructor_called) {
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].destructor_called = 1;
zend_try {
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].bucket.obj.dtor(EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].bucket.obj.object, Z_OBJ_HANDLE(p->z) TSRMLS_CC);
} zend_end_try();
}
}
p = p->u.next;
}
p = GC_G(free_list);
while (p) {
q = p->u.next;
if (Z_TYPE(p->z) == IS_OBJECT) {
if (EG(objects_store).object_buckets &&
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].valid &&
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].bucket.obj.refcount <= 0) {
if (EXPECTED(Z_OBJ_HANDLER(p->z, get_properties) != NULL)) {
GC_G(gc_active) = 1;
Z_OBJPROP(p->z)->pDestructor = NULL;
GC_G(gc_active) = 0;
}
EG(objects_store).object_buckets[Z_OBJ_HANDLE(p->z)].bucket.obj.refcount = 1;
zend_objects_store_del_ref_by_handle(Z_OBJ_HANDLE(p->z) TSRMLS_CC);
zend_try {
zend_objects_store_del_ref_by_handle(Z_OBJ_HANDLE(p->z) TSRMLS_CC);
} zend_end_try();
}
} else {
if (Z_TYPE(p->z) == IS_ARRAY) {
Z_ARRVAL(p->z)->pDestructor = NULL;
}
zval_dtor(&p->z);
zend_try {
zval_dtor(&p->z);
} zend_end_try();
}
FREE_ZVAL_EX(&p->z);
p = q;
count++;
}
GC_G(collected) += count;
GC_G(free_list) = orig_free_list;
}
return count;

View File

@ -105,6 +105,7 @@ typedef struct _zend_gc_globals {
gc_root_buffer *unused; /* list of unused buffers */
zval_gc_info *zval_to_free; /* temporaryt list of zvals to free */
zval_gc_info *free_list;
zend_uint gc_runs;
zend_uint collected;
@ -138,6 +139,7 @@ BEGIN_EXTERN_C()
ZEND_API int gc_collect_cycles(TSRMLS_D);
ZEND_API void gc_zval_possible_root(zval *zv TSRMLS_DC);
ZEND_API void gc_zobj_possible_root(zval *zv TSRMLS_DC);
ZEND_API void _gc_remove_zval_from_buffer(zval *zv);
ZEND_API void gc_globals_ctor(TSRMLS_D);
ZEND_API void gc_globals_dtor(TSRMLS_D);
ZEND_API void gc_init(TSRMLS_D);
@ -163,7 +165,7 @@ END_EXTERN_C()
#define GC_REMOVE_ZOBJ_FROM_BUFFER(obj) \
do { \
if (GC_ADDRESS((obj)->buffered)) { \
if (GC_ADDRESS((obj)->buffered) && !GC_G(gc_active)) { \
GC_BENCH_INC(zobj_remove_from_buffer); \
GC_REMOVE_FROM_BUFFER(GC_ADDRESS((obj)->buffered)); \
(obj)->buffered = NULL; \
@ -188,15 +190,8 @@ static zend_always_inline void gc_remove_from_buffer(gc_root_buffer *root TSRMLS
static zend_always_inline void gc_remove_zval_from_buffer(zval* z)
{
gc_root_buffer* root_buffer;
root_buffer = GC_ADDRESS(((zval_gc_info*)z)->u.buffered);
if (root_buffer) {
TSRMLS_FETCH();
GC_BENCH_INC(zval_remove_from_buffer);
GC_REMOVE_FROM_BUFFER(root_buffer);
((zval_gc_info*)z)->u.buffered = NULL;
if (GC_ADDRESS(((zval_gc_info*)z)->u.buffered)) {
_gc_remove_zval_from_buffer(z);
}
}