mirror of
https://github.com/php/php-src.git
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5513f00a97
Under the special circumstance where a garbage collected objects bucket slot was not reused until the end of the script, we get access into freed memory... No test added as it usually is valgrind-only, and only sometimes when the memory happens to have changed (i.e. (GC_FLAGS(obj) & IS_OBJ_FREE_CALLED) == 0), it actually *may* segfault
1161 lines
28 KiB
C
1161 lines
28 KiB
C
/*
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+----------------------------------------------------------------------+
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| Zend Engine |
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+----------------------------------------------------------------------+
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| Copyright (c) 1998-2016 Zend Technologies Ltd. (http://www.zend.com) |
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+----------------------------------------------------------------------+
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| This source file is subject to version 2.00 of the Zend license, |
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| that is bundled with this package in the file LICENSE, and is |
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| available through the world-wide-web at the following url: |
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| http://www.zend.com/license/2_00.txt. |
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| If you did not receive a copy of the Zend license and are unable to |
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| obtain it through the world-wide-web, please send a note to |
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| license@zend.com so we can mail you a copy immediately. |
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+----------------------------------------------------------------------+
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| Authors: David Wang <planetbeing@gmail.com> |
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| Dmitry Stogov <dmitry@zend.com> |
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+----------------------------------------------------------------------+
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*/
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/* $Id$ */
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#include "zend.h"
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#include "zend_API.h"
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|
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/* one (0) is reserved */
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#define GC_ROOT_BUFFER_MAX_ENTRIES 10001
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#define GC_FAKE_BUFFER_FLAG 0x80
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#define GC_TYPE_MASK 0x7f
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|
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#define GC_HAS_DESTRUCTORS (1<<0)
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|
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#ifndef ZEND_GC_DEBUG
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# define ZEND_GC_DEBUG 0
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#endif
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#define GC_NUM_ADDITIONAL_ENTRIES \
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((4096 - ZEND_MM_OVERHEAD - sizeof(void*) * 2) / sizeof(gc_root_buffer))
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typedef struct _gc_addtional_bufer gc_additional_buffer;
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struct _gc_addtional_bufer {
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uint32_t used;
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gc_additional_buffer *next;
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gc_root_buffer buf[GC_NUM_ADDITIONAL_ENTRIES];
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};
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|
|
|
#ifdef ZTS
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|
ZEND_API int gc_globals_id;
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#else
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ZEND_API zend_gc_globals gc_globals;
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#endif
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|
|
ZEND_API int (*gc_collect_cycles)(void);
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|
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#define GC_REMOVE_FROM_ROOTS(current) \
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gc_remove_from_roots((current))
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|
|
|
#if ZEND_GC_DEBUG > 1
|
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# define GC_TRACE(format, ...) fprintf(stderr, format "\n", ##__VA_ARGS__);
|
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# define GC_TRACE_REF(ref, format, ...) \
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do { \
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gc_trace_ref((zend_refcounted *) ref); \
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fprintf(stderr, format "\n", ##__VA_ARGS__); \
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} while (0)
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# define GC_TRACE_SET_COLOR(ref, color) \
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GC_TRACE_REF(ref, "->%s", gc_color_name(color))
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#else
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# define GC_TRACE_REF(ref, format, ...)
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# define GC_TRACE_SET_COLOR(ref, new_color)
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# define GC_TRACE(str)
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#endif
|
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|
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#define GC_REF_SET_ADDRESS(ref, a) \
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GC_INFO_SET_ADDRESS(GC_INFO(ref), a)
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#define GC_REF_GET_COLOR(ref) \
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GC_INFO_GET_COLOR(GC_INFO(ref))
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#define GC_REF_SET_COLOR(ref, c) \
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do { GC_TRACE_SET_COLOR(ref, c); GC_INFO_SET_COLOR(GC_INFO(ref), c); } while (0)
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#define GC_REF_SET_BLACK(ref) \
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do { GC_TRACE_SET_COLOR(ref, GC_BLACK); GC_INFO_SET_BLACK(GC_INFO(ref)); } while (0)
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#define GC_REF_SET_PURPLE(ref) \
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do { GC_TRACE_SET_COLOR(ref, GC_PURPLE); GC_INFO_SET_PURPLE(GC_INFO(ref)); } while (0)
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|
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#if ZEND_GC_DEBUG > 1
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static const char *gc_color_name(uint32_t color) {
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switch (color) {
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case GC_BLACK: return "black";
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case GC_WHITE: return "white";
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case GC_GREY: return "grey";
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case GC_PURPLE: return "purple";
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default: return "unknown";
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}
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}
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static void gc_trace_ref(zend_refcounted *ref) {
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if (GC_TYPE(ref) == IS_OBJECT) {
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zend_object *obj = (zend_object *) ref;
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fprintf(stderr, "[%p] rc=%d addr=%d %s object(%s)#%d ",
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ref, GC_REFCOUNT(ref), GC_ADDRESS(GC_INFO(ref)),
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gc_color_name(GC_REF_GET_COLOR(ref)),
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obj->ce->name->val, obj->handle);
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} else if (GC_TYPE(ref) == IS_ARRAY) {
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zend_array *arr = (zend_array *) ref;
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fprintf(stderr, "[%p] rc=%d addr=%d %s array(%d) ",
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ref, GC_REFCOUNT(ref), GC_ADDRESS(GC_INFO(ref)),
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gc_color_name(GC_REF_GET_COLOR(ref)),
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zend_hash_num_elements(arr));
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} else {
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fprintf(stderr, "[%p] rc=%d addr=%d %s %s ",
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ref, GC_REFCOUNT(ref), GC_ADDRESS(GC_INFO(ref)),
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gc_color_name(GC_REF_GET_COLOR(ref)),
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zend_get_type_by_const(GC_TYPE(ref)));
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}
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}
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|
#endif
|
|
|
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static zend_always_inline void gc_remove_from_roots(gc_root_buffer *root)
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|
{
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|
root->next->prev = root->prev;
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root->prev->next = root->next;
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|
root->prev = GC_G(unused);
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GC_G(unused) = root;
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GC_BENCH_DEC(root_buf_length);
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|
}
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|
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static void root_buffer_dtor(zend_gc_globals *gc_globals)
|
|
{
|
|
if (gc_globals->buf) {
|
|
free(gc_globals->buf);
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|
gc_globals->buf = NULL;
|
|
}
|
|
}
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|
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static void gc_globals_ctor_ex(zend_gc_globals *gc_globals)
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|
{
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gc_globals->gc_enabled = 0;
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gc_globals->gc_active = 0;
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|
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gc_globals->buf = NULL;
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|
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gc_globals->roots.next = &gc_globals->roots;
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gc_globals->roots.prev = &gc_globals->roots;
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gc_globals->unused = NULL;
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gc_globals->next_to_free = NULL;
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|
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gc_globals->to_free.next = &gc_globals->to_free;
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gc_globals->to_free.prev = &gc_globals->to_free;
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gc_globals->gc_runs = 0;
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gc_globals->collected = 0;
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|
|
#if GC_BENCH
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gc_globals->root_buf_length = 0;
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|
gc_globals->root_buf_peak = 0;
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|
gc_globals->zval_possible_root = 0;
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gc_globals->zval_buffered = 0;
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|
gc_globals->zval_remove_from_buffer = 0;
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gc_globals->zval_marked_grey = 0;
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|
#endif
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}
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|
|
|
ZEND_API void gc_globals_ctor(void)
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{
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#ifdef ZTS
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ts_allocate_id(&gc_globals_id, sizeof(zend_gc_globals), (ts_allocate_ctor) gc_globals_ctor_ex, (ts_allocate_dtor) root_buffer_dtor);
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#else
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gc_globals_ctor_ex(&gc_globals);
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#endif
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}
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|
|
ZEND_API void gc_globals_dtor(void)
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|
{
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#ifndef ZTS
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root_buffer_dtor(&gc_globals);
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#endif
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|
}
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|
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ZEND_API void gc_reset(void)
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{
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GC_G(gc_runs) = 0;
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GC_G(collected) = 0;
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GC_G(gc_full) = 0;
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|
|
#if GC_BENCH
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GC_G(root_buf_length) = 0;
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GC_G(root_buf_peak) = 0;
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GC_G(zval_possible_root) = 0;
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GC_G(zval_buffered) = 0;
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GC_G(zval_remove_from_buffer) = 0;
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GC_G(zval_marked_grey) = 0;
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#endif
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GC_G(roots).next = &GC_G(roots);
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GC_G(roots).prev = &GC_G(roots);
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GC_G(to_free).next = &GC_G(to_free);
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GC_G(to_free).prev = &GC_G(to_free);
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|
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if (GC_G(buf)) {
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GC_G(unused) = NULL;
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GC_G(first_unused) = GC_G(buf) + 1;
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} else {
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|
GC_G(unused) = NULL;
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|
GC_G(first_unused) = NULL;
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|
GC_G(last_unused) = NULL;
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}
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}
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|
|
ZEND_API void gc_init(void)
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{
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if (GC_G(buf) == NULL && GC_G(gc_enabled)) {
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GC_G(buf) = (gc_root_buffer*) malloc(sizeof(gc_root_buffer) * GC_ROOT_BUFFER_MAX_ENTRIES);
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GC_G(last_unused) = &GC_G(buf)[GC_ROOT_BUFFER_MAX_ENTRIES];
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gc_reset();
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}
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}
|
|
|
|
ZEND_API void ZEND_FASTCALL gc_possible_root(zend_refcounted *ref)
|
|
{
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|
gc_root_buffer *newRoot;
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|
|
|
if (UNEXPECTED(CG(unclean_shutdown)) || UNEXPECTED(GC_G(gc_active))) {
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return;
|
|
}
|
|
|
|
ZEND_ASSERT(GC_TYPE(ref) == IS_ARRAY || GC_TYPE(ref) == IS_OBJECT);
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|
ZEND_ASSERT(EXPECTED(GC_REF_GET_COLOR(ref) == GC_BLACK));
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ZEND_ASSERT(!GC_ADDRESS(GC_INFO(ref)));
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|
|
GC_BENCH_INC(zval_possible_root);
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|
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newRoot = GC_G(unused);
|
|
if (newRoot) {
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|
GC_G(unused) = newRoot->prev;
|
|
} else if (GC_G(first_unused) != GC_G(last_unused)) {
|
|
newRoot = GC_G(first_unused);
|
|
GC_G(first_unused)++;
|
|
} else {
|
|
if (!GC_G(gc_enabled)) {
|
|
return;
|
|
}
|
|
GC_REFCOUNT(ref)++;
|
|
gc_collect_cycles();
|
|
GC_REFCOUNT(ref)--;
|
|
if (UNEXPECTED(GC_REFCOUNT(ref)) == 0) {
|
|
zval_dtor_func_for_ptr(ref);
|
|
return;
|
|
}
|
|
if (UNEXPECTED(GC_INFO(ref))) {
|
|
return;
|
|
}
|
|
newRoot = GC_G(unused);
|
|
if (!newRoot) {
|
|
#if ZEND_GC_DEBUG
|
|
if (!GC_G(gc_full)) {
|
|
fprintf(stderr, "GC: no space to record new root candidate\n");
|
|
GC_G(gc_full) = 1;
|
|
}
|
|
#endif
|
|
return;
|
|
}
|
|
GC_G(unused) = newRoot->prev;
|
|
}
|
|
|
|
GC_TRACE_SET_COLOR(ref, GC_PURPLE);
|
|
GC_INFO(ref) = (newRoot - GC_G(buf)) | GC_PURPLE;
|
|
newRoot->ref = ref;
|
|
|
|
newRoot->next = GC_G(roots).next;
|
|
newRoot->prev = &GC_G(roots);
|
|
GC_G(roots).next->prev = newRoot;
|
|
GC_G(roots).next = newRoot;
|
|
|
|
GC_BENCH_INC(zval_buffered);
|
|
GC_BENCH_INC(root_buf_length);
|
|
GC_BENCH_PEAK(root_buf_peak, root_buf_length);
|
|
}
|
|
|
|
ZEND_API void ZEND_FASTCALL gc_remove_from_buffer(zend_refcounted *ref)
|
|
{
|
|
gc_root_buffer *root;
|
|
|
|
ZEND_ASSERT(GC_ADDRESS(GC_INFO(ref)));
|
|
ZEND_ASSERT(GC_ADDRESS(GC_INFO(ref)) < GC_ROOT_BUFFER_MAX_ENTRIES);
|
|
|
|
GC_BENCH_INC(zval_remove_from_buffer);
|
|
|
|
root = GC_G(buf) + GC_ADDRESS(GC_INFO(ref));
|
|
if (GC_REF_GET_COLOR(ref) != GC_BLACK) {
|
|
GC_TRACE_SET_COLOR(ref, GC_PURPLE);
|
|
}
|
|
GC_INFO(ref) = 0;
|
|
GC_REMOVE_FROM_ROOTS(root);
|
|
|
|
/* updete next root that is going to be freed */
|
|
if (GC_G(next_to_free) == root) {
|
|
GC_G(next_to_free) = root->next;
|
|
}
|
|
}
|
|
|
|
static void gc_scan_black(zend_refcounted *ref)
|
|
{
|
|
HashTable *ht;
|
|
Bucket *p, *end;
|
|
zval *zv;
|
|
|
|
tail_call:
|
|
ht = NULL;
|
|
GC_REF_SET_BLACK(ref);
|
|
|
|
if (GC_TYPE(ref) == IS_OBJECT && !(GC_FLAGS(ref) & IS_OBJ_FREE_CALLED)) {
|
|
zend_object_get_gc_t get_gc;
|
|
zend_object *obj = (zend_object*)ref;
|
|
|
|
if (EXPECTED(IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle]) &&
|
|
(get_gc = obj->handlers->get_gc) != NULL)) {
|
|
int n;
|
|
zval *zv, *end;
|
|
zval tmp;
|
|
|
|
ZVAL_OBJ(&tmp, obj);
|
|
ht = get_gc(&tmp, &zv, &n);
|
|
end = zv + n;
|
|
if (EXPECTED(!ht)) {
|
|
if (!n) return;
|
|
while (!Z_REFCOUNTED_P(--end)) {
|
|
if (zv == end) return;
|
|
}
|
|
}
|
|
while (zv != end) {
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
if (GC_REF_GET_COLOR(ref) != GC_BLACK) {
|
|
gc_scan_black(ref);
|
|
}
|
|
}
|
|
zv++;
|
|
}
|
|
if (EXPECTED(!ht)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
if (GC_REF_GET_COLOR(ref) != GC_BLACK) {
|
|
goto tail_call;
|
|
}
|
|
return;
|
|
}
|
|
} else {
|
|
return;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_ARRAY) {
|
|
if ((zend_array*)ref != &EG(symbol_table)) {
|
|
ht = (zend_array*)ref;
|
|
} else {
|
|
return;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_REFERENCE) {
|
|
if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
|
|
ref = Z_COUNTED(((zend_reference*)ref)->val);
|
|
GC_REFCOUNT(ref)++;
|
|
if (GC_REF_GET_COLOR(ref) != GC_BLACK) {
|
|
goto tail_call;
|
|
}
|
|
}
|
|
return;
|
|
} else {
|
|
return;
|
|
}
|
|
|
|
if (!ht->nNumUsed) return;
|
|
p = ht->arData;
|
|
end = p + ht->nNumUsed;
|
|
while (1) {
|
|
end--;
|
|
zv = &end->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
break;
|
|
}
|
|
if (p == end) return;
|
|
}
|
|
while (p != end) {
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
if (GC_REF_GET_COLOR(ref) != GC_BLACK) {
|
|
gc_scan_black(ref);
|
|
}
|
|
}
|
|
p++;
|
|
}
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
if (GC_REF_GET_COLOR(ref) != GC_BLACK) {
|
|
goto tail_call;
|
|
}
|
|
}
|
|
|
|
static void gc_mark_grey(zend_refcounted *ref)
|
|
{
|
|
HashTable *ht;
|
|
Bucket *p, *end;
|
|
zval *zv;
|
|
|
|
tail_call:
|
|
if (GC_REF_GET_COLOR(ref) != GC_GREY) {
|
|
ht = NULL;
|
|
GC_BENCH_INC(zval_marked_grey);
|
|
GC_REF_SET_COLOR(ref, GC_GREY);
|
|
|
|
if (GC_TYPE(ref) == IS_OBJECT && !(GC_FLAGS(ref) & IS_OBJ_FREE_CALLED)) {
|
|
zend_object_get_gc_t get_gc;
|
|
zend_object *obj = (zend_object*)ref;
|
|
|
|
if (EXPECTED(IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle]) &&
|
|
(get_gc = obj->handlers->get_gc) != NULL)) {
|
|
int n;
|
|
zval *zv, *end;
|
|
zval tmp;
|
|
|
|
ZVAL_OBJ(&tmp, obj);
|
|
ht = get_gc(&tmp, &zv, &n);
|
|
end = zv + n;
|
|
if (EXPECTED(!ht)) {
|
|
if (!n) return;
|
|
while (!Z_REFCOUNTED_P(--end)) {
|
|
if (zv == end) return;
|
|
}
|
|
}
|
|
while (zv != end) {
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)--;
|
|
gc_mark_grey(ref);
|
|
}
|
|
zv++;
|
|
}
|
|
if (EXPECTED(!ht)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)--;
|
|
goto tail_call;
|
|
}
|
|
} else {
|
|
return;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_ARRAY) {
|
|
if (((zend_array*)ref) == &EG(symbol_table)) {
|
|
GC_REF_SET_BLACK(ref);
|
|
return;
|
|
} else {
|
|
ht = (zend_array*)ref;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_REFERENCE) {
|
|
if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
|
|
if (UNEXPECTED(!EG(objects_store).object_buckets) &&
|
|
Z_TYPE(((zend_reference*)ref)->val) == IS_OBJECT) {
|
|
Z_TYPE_INFO(((zend_reference*)ref)->val) = IS_NULL;
|
|
return;
|
|
}
|
|
ref = Z_COUNTED(((zend_reference*)ref)->val);
|
|
GC_REFCOUNT(ref)--;
|
|
goto tail_call;
|
|
}
|
|
return;
|
|
} else {
|
|
return;
|
|
}
|
|
|
|
if (!ht->nNumUsed) return;
|
|
p = ht->arData;
|
|
end = p + ht->nNumUsed;
|
|
while (1) {
|
|
end--;
|
|
zv = &end->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
break;
|
|
}
|
|
if (p == end) return;
|
|
}
|
|
while (p != end) {
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
if (Z_TYPE_P(zv) == IS_OBJECT &&
|
|
UNEXPECTED(!EG(objects_store).object_buckets)) {
|
|
Z_TYPE_INFO_P(zv) = IS_NULL;
|
|
} else {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)--;
|
|
gc_mark_grey(ref);
|
|
}
|
|
}
|
|
p++;
|
|
}
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_TYPE_P(zv) == IS_OBJECT &&
|
|
UNEXPECTED(!EG(objects_store).object_buckets)) {
|
|
Z_TYPE_INFO_P(zv) = IS_NULL;
|
|
} else {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)--;
|
|
goto tail_call;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void gc_mark_roots(void)
|
|
{
|
|
gc_root_buffer *current = GC_G(roots).next;
|
|
|
|
while (current != &GC_G(roots)) {
|
|
if (GC_REF_GET_COLOR(current->ref) == GC_PURPLE) {
|
|
gc_mark_grey(current->ref);
|
|
}
|
|
current = current->next;
|
|
}
|
|
}
|
|
|
|
static void gc_scan(zend_refcounted *ref)
|
|
{
|
|
HashTable *ht;
|
|
Bucket *p, *end;
|
|
zval *zv;
|
|
|
|
tail_call:
|
|
if (GC_REF_GET_COLOR(ref) == GC_GREY) {
|
|
if (GC_REFCOUNT(ref) > 0) {
|
|
gc_scan_black(ref);
|
|
} else {
|
|
GC_REF_SET_COLOR(ref, GC_WHITE);
|
|
if (GC_TYPE(ref) == IS_OBJECT && !(GC_FLAGS(ref) & IS_OBJ_FREE_CALLED)) {
|
|
zend_object_get_gc_t get_gc;
|
|
zend_object *obj = (zend_object*)ref;
|
|
|
|
if (EXPECTED(IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle]) &&
|
|
(get_gc = obj->handlers->get_gc) != NULL)) {
|
|
int n;
|
|
zval *zv, *end;
|
|
zval tmp;
|
|
|
|
ZVAL_OBJ(&tmp, obj);
|
|
ht = get_gc(&tmp, &zv, &n);
|
|
end = zv + n;
|
|
if (EXPECTED(!ht)) {
|
|
if (!n) return;
|
|
while (!Z_REFCOUNTED_P(--end)) {
|
|
if (zv == end) return;
|
|
}
|
|
}
|
|
while (zv != end) {
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
gc_scan(ref);
|
|
}
|
|
zv++;
|
|
}
|
|
if (EXPECTED(!ht)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
goto tail_call;
|
|
}
|
|
} else {
|
|
return;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_ARRAY) {
|
|
if ((zend_array*)ref == &EG(symbol_table)) {
|
|
GC_REF_SET_BLACK(ref);
|
|
return;
|
|
} else {
|
|
ht = (zend_array*)ref;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_REFERENCE) {
|
|
if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
|
|
ref = Z_COUNTED(((zend_reference*)ref)->val);
|
|
goto tail_call;
|
|
}
|
|
return;
|
|
} else {
|
|
return;
|
|
}
|
|
|
|
if (!ht->nNumUsed) return;
|
|
p = ht->arData;
|
|
end = p + ht->nNumUsed;
|
|
while (1) {
|
|
end--;
|
|
zv = &end->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
break;
|
|
}
|
|
if (p == end) return;
|
|
}
|
|
while (p != end) {
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
gc_scan(ref);
|
|
}
|
|
p++;
|
|
}
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
ref = Z_COUNTED_P(zv);
|
|
goto tail_call;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void gc_scan_roots(void)
|
|
{
|
|
gc_root_buffer *current = GC_G(roots).next;
|
|
|
|
while (current != &GC_G(roots)) {
|
|
gc_scan(current->ref);
|
|
current = current->next;
|
|
}
|
|
}
|
|
|
|
static void gc_add_garbage(zend_refcounted *ref, gc_additional_buffer **additional_buffer)
|
|
{
|
|
gc_root_buffer *buf = GC_G(unused);
|
|
|
|
if (buf) {
|
|
GC_G(unused) = buf->prev;
|
|
#if 1
|
|
/* optimization: color is already GC_BLACK (0) */
|
|
GC_INFO(ref) = buf - GC_G(buf);
|
|
#else
|
|
GC_REF_SET_ADDRESS(ref, buf - GC_G(buf));
|
|
#endif
|
|
} else if (GC_G(first_unused) != GC_G(last_unused)) {
|
|
buf = GC_G(first_unused);
|
|
GC_G(first_unused)++;
|
|
#if 1
|
|
/* optimization: color is already GC_BLACK (0) */
|
|
GC_INFO(ref) = buf - GC_G(buf);
|
|
#else
|
|
GC_REF_SET_ADDRESS(ref, buf - GC_G(buf));
|
|
#endif
|
|
} else {
|
|
/* If we don't have free slots in the buffer, allocate a new one and
|
|
* set it's address to GC_ROOT_BUFFER_MAX_ENTRIES that have special
|
|
* meaning.
|
|
*/
|
|
if (!*additional_buffer || (*additional_buffer)->used == GC_NUM_ADDITIONAL_ENTRIES) {
|
|
gc_additional_buffer *new_buffer = emalloc(sizeof(gc_additional_buffer));
|
|
new_buffer->used = 0;
|
|
new_buffer->next = *additional_buffer;
|
|
*additional_buffer = new_buffer;
|
|
}
|
|
buf = (*additional_buffer)->buf + (*additional_buffer)->used;
|
|
(*additional_buffer)->used++;
|
|
#if 1
|
|
/* optimization: color is already GC_BLACK (0) */
|
|
GC_INFO(ref) = GC_ROOT_BUFFER_MAX_ENTRIES;
|
|
#else
|
|
GC_REF_SET_ADDRESS(ref, GC_ROOT_BUFFER_MAX_ENTRIES);
|
|
#endif
|
|
/* modify type to prevent indirect destruction */
|
|
GC_TYPE(ref) |= GC_FAKE_BUFFER_FLAG;
|
|
}
|
|
if (buf) {
|
|
GC_REFCOUNT(ref)++;
|
|
buf->ref = ref;
|
|
buf->next = GC_G(roots).next;
|
|
buf->prev = &GC_G(roots);
|
|
GC_G(roots).next->prev = buf;
|
|
GC_G(roots).next = buf;
|
|
}
|
|
}
|
|
|
|
static int gc_collect_white(zend_refcounted *ref, uint32_t *flags, gc_additional_buffer **additional_buffer)
|
|
{
|
|
int count = 0;
|
|
HashTable *ht;
|
|
Bucket *p, *end;
|
|
zval *zv;
|
|
|
|
tail_call:
|
|
if (GC_REF_GET_COLOR(ref) == GC_WHITE) {
|
|
ht = NULL;
|
|
GC_REF_SET_BLACK(ref);
|
|
|
|
/* don't count references for compatibility ??? */
|
|
if (GC_TYPE(ref) != IS_REFERENCE) {
|
|
count++;
|
|
}
|
|
|
|
if (GC_TYPE(ref) == IS_OBJECT && !(GC_FLAGS(ref) & IS_OBJ_FREE_CALLED)) {
|
|
zend_object_get_gc_t get_gc;
|
|
zend_object *obj = (zend_object*)ref;
|
|
|
|
if (EXPECTED(IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle]) &&
|
|
(get_gc = obj->handlers->get_gc) != NULL)) {
|
|
int n;
|
|
zval *zv, *end;
|
|
zval tmp;
|
|
|
|
#if 1
|
|
/* optimization: color is GC_BLACK (0) */
|
|
if (!GC_INFO(ref)) {
|
|
#else
|
|
if (!GC_ADDRESS(GC_INFO(ref))) {
|
|
#endif
|
|
gc_add_garbage(ref, additional_buffer);
|
|
}
|
|
if (obj->handlers->dtor_obj &&
|
|
((obj->handlers->dtor_obj != zend_objects_destroy_object) ||
|
|
(obj->ce->destructor != NULL))) {
|
|
*flags |= GC_HAS_DESTRUCTORS;
|
|
}
|
|
ZVAL_OBJ(&tmp, obj);
|
|
ht = get_gc(&tmp, &zv, &n);
|
|
end = zv + n;
|
|
if (EXPECTED(!ht)) {
|
|
if (!n) return count;
|
|
while (!Z_REFCOUNTED_P(--end)) {
|
|
/* count non-refcounted for compatibility ??? */
|
|
if (Z_TYPE_P(zv) != IS_UNDEF) {
|
|
count++;
|
|
}
|
|
if (zv == end) return count;
|
|
}
|
|
}
|
|
while (zv != end) {
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
count += gc_collect_white(ref, flags, additional_buffer);
|
|
/* count non-refcounted for compatibility ??? */
|
|
} else if (Z_TYPE_P(zv) != IS_UNDEF) {
|
|
count++;
|
|
}
|
|
zv++;
|
|
}
|
|
if (EXPECTED(!ht)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
goto tail_call;
|
|
}
|
|
} else {
|
|
return count;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_ARRAY) {
|
|
#if 1
|
|
/* optimization: color is GC_BLACK (0) */
|
|
if (!GC_INFO(ref)) {
|
|
#else
|
|
if (!GC_ADDRESS(GC_INFO(ref))) {
|
|
#endif
|
|
gc_add_garbage(ref, additional_buffer);
|
|
}
|
|
ht = (zend_array*)ref;
|
|
} else if (GC_TYPE(ref) == IS_REFERENCE) {
|
|
if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
|
|
ref = Z_COUNTED(((zend_reference*)ref)->val);
|
|
GC_REFCOUNT(ref)++;
|
|
goto tail_call;
|
|
}
|
|
return count;
|
|
} else {
|
|
return count;
|
|
}
|
|
|
|
if (!ht->nNumUsed) return count;
|
|
p = ht->arData;
|
|
end = p + ht->nNumUsed;
|
|
while (1) {
|
|
end--;
|
|
zv = &end->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
break;
|
|
}
|
|
/* count non-refcounted for compatibility ??? */
|
|
if (Z_TYPE_P(zv) != IS_UNDEF) {
|
|
count++;
|
|
}
|
|
if (p == end) return count;
|
|
}
|
|
while (p != end) {
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
count += gc_collect_white(ref, flags, additional_buffer);
|
|
/* count non-refcounted for compatibility ??? */
|
|
} else if (Z_TYPE_P(zv) != IS_UNDEF) {
|
|
count++;
|
|
}
|
|
p++;
|
|
}
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
ref = Z_COUNTED_P(zv);
|
|
GC_REFCOUNT(ref)++;
|
|
goto tail_call;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static int gc_collect_roots(uint32_t *flags, gc_additional_buffer **additional_buffer)
|
|
{
|
|
int count = 0;
|
|
gc_root_buffer *current = GC_G(roots).next;
|
|
|
|
/* remove non-garbage from the list */
|
|
while (current != &GC_G(roots)) {
|
|
gc_root_buffer *next = current->next;
|
|
if (GC_REF_GET_COLOR(current->ref) == GC_BLACK) {
|
|
GC_INFO(current->ref) = 0; /* reset GC_ADDRESS() and keep GC_BLACK */
|
|
GC_REMOVE_FROM_ROOTS(current);
|
|
}
|
|
current = next;
|
|
}
|
|
|
|
current = GC_G(roots).next;
|
|
while (current != &GC_G(roots)) {
|
|
GC_REFCOUNT(current->ref)++;
|
|
if (GC_REF_GET_COLOR(current->ref) == GC_WHITE) {
|
|
count += gc_collect_white(current->ref, flags, additional_buffer);
|
|
}
|
|
current = current->next;
|
|
}
|
|
|
|
/* relink remaining roots into list to free */
|
|
if (GC_G(roots).next != &GC_G(roots)) {
|
|
if (GC_G(to_free).next == &GC_G(to_free)) {
|
|
/* move roots into list to free */
|
|
GC_G(to_free).next = GC_G(roots).next;
|
|
GC_G(to_free).prev = GC_G(roots).prev;
|
|
GC_G(to_free).next->prev = &GC_G(to_free);
|
|
GC_G(to_free).prev->next = &GC_G(to_free);
|
|
} else {
|
|
/* add roots into list to free */
|
|
GC_G(to_free).prev->next = GC_G(roots).next;
|
|
GC_G(roots).next->prev = GC_G(to_free).prev;
|
|
GC_G(roots).prev->next = &GC_G(to_free);
|
|
GC_G(to_free).prev = GC_G(roots).prev;
|
|
}
|
|
|
|
GC_G(roots).next = &GC_G(roots);
|
|
GC_G(roots).prev = &GC_G(roots);
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static void gc_remove_nested_data_from_buffer(zend_refcounted *ref, gc_root_buffer *root)
|
|
{
|
|
HashTable *ht = NULL;
|
|
Bucket *p, *end;
|
|
zval *zv;
|
|
|
|
tail_call:
|
|
if (root ||
|
|
(GC_ADDRESS(GC_INFO(ref)) != 0 &&
|
|
GC_REF_GET_COLOR(ref) == GC_BLACK &&
|
|
GC_ADDRESS(GC_INFO(ref)) != GC_ROOT_BUFFER_MAX_ENTRIES)) {
|
|
GC_TRACE_REF(ref, "removing from buffer");
|
|
GC_REFCOUNT(ref)--;
|
|
if (root) {
|
|
GC_INFO(ref) = 0;
|
|
GC_REMOVE_FROM_ROOTS(root);
|
|
root = NULL;
|
|
} else {
|
|
GC_REMOVE_FROM_BUFFER(ref);
|
|
}
|
|
|
|
if (GC_TYPE(ref) == IS_OBJECT && !(GC_FLAGS(ref) & IS_OBJ_FREE_CALLED)) {
|
|
zend_object_get_gc_t get_gc;
|
|
zend_object *obj = (zend_object*)ref;
|
|
|
|
if (EXPECTED(IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle]) &&
|
|
(get_gc = obj->handlers->get_gc) != NULL)) {
|
|
int n;
|
|
zval *zv, *end;
|
|
zval tmp;
|
|
|
|
ZVAL_OBJ(&tmp, obj);
|
|
ht = get_gc(&tmp, &zv, &n);
|
|
end = zv + n;
|
|
if (EXPECTED(!ht)) {
|
|
if (!n) return;
|
|
while (!Z_REFCOUNTED_P(--end)) {
|
|
if (zv == end) return;
|
|
}
|
|
}
|
|
while (zv != end) {
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
gc_remove_nested_data_from_buffer(ref, NULL);
|
|
}
|
|
zv++;
|
|
}
|
|
if (EXPECTED(!ht)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
goto tail_call;
|
|
}
|
|
} else {
|
|
return;
|
|
}
|
|
} else if (GC_TYPE(ref) == IS_ARRAY) {
|
|
ht = (zend_array*)ref;
|
|
} else if (GC_TYPE(ref) == IS_REFERENCE) {
|
|
if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
|
|
ref = Z_COUNTED(((zend_reference*)ref)->val);
|
|
goto tail_call;
|
|
}
|
|
return;
|
|
} else {
|
|
return;
|
|
}
|
|
|
|
if (!ht->nNumUsed) return;
|
|
p = ht->arData;
|
|
end = p + ht->nNumUsed;
|
|
while (1) {
|
|
end--;
|
|
zv = &end->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
break;
|
|
}
|
|
if (p == end) return;
|
|
}
|
|
while (p != end) {
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
if (Z_REFCOUNTED_P(zv)) {
|
|
ref = Z_COUNTED_P(zv);
|
|
gc_remove_nested_data_from_buffer(ref, NULL);
|
|
}
|
|
p++;
|
|
}
|
|
zv = &p->val;
|
|
if (Z_TYPE_P(zv) == IS_INDIRECT) {
|
|
zv = Z_INDIRECT_P(zv);
|
|
}
|
|
ref = Z_COUNTED_P(zv);
|
|
goto tail_call;
|
|
}
|
|
}
|
|
|
|
ZEND_API int zend_gc_collect_cycles(void)
|
|
{
|
|
int count = 0;
|
|
|
|
if (GC_G(roots).next != &GC_G(roots)) {
|
|
gc_root_buffer *current, *next, *orig_next_to_free;
|
|
zend_refcounted *p;
|
|
gc_root_buffer to_free;
|
|
uint32_t gc_flags = 0;
|
|
gc_additional_buffer *additional_buffer;
|
|
#if ZEND_GC_DEBUG
|
|
zend_bool orig_gc_full;
|
|
#endif
|
|
|
|
if (GC_G(gc_active)) {
|
|
return 0;
|
|
}
|
|
|
|
GC_TRACE("Collecting cycles");
|
|
GC_G(gc_runs)++;
|
|
GC_G(gc_active) = 1;
|
|
|
|
GC_TRACE("Marking roots");
|
|
gc_mark_roots();
|
|
GC_TRACE("Scanning roots");
|
|
gc_scan_roots();
|
|
|
|
#if ZEND_GC_DEBUG
|
|
orig_gc_full = GC_G(gc_full);
|
|
GC_G(gc_full) = 0;
|
|
#endif
|
|
|
|
GC_TRACE("Collecting roots");
|
|
additional_buffer = NULL;
|
|
count = gc_collect_roots(&gc_flags, &additional_buffer);
|
|
#if ZEND_GC_DEBUG
|
|
GC_G(gc_full) = orig_gc_full;
|
|
#endif
|
|
GC_G(gc_active) = 0;
|
|
|
|
if (GC_G(to_free).next == &GC_G(to_free)) {
|
|
/* nothing to free */
|
|
GC_TRACE("Nothing to free");
|
|
return 0;
|
|
}
|
|
|
|
/* Copy global to_free list into local list */
|
|
to_free.next = GC_G(to_free).next;
|
|
to_free.prev = GC_G(to_free).prev;
|
|
to_free.next->prev = &to_free;
|
|
to_free.prev->next = &to_free;
|
|
|
|
/* Free global list */
|
|
GC_G(to_free).next = &GC_G(to_free);
|
|
GC_G(to_free).prev = &GC_G(to_free);
|
|
|
|
orig_next_to_free = GC_G(next_to_free);
|
|
|
|
#if ZEND_GC_DEBUG
|
|
orig_gc_full = GC_G(gc_full);
|
|
GC_G(gc_full) = 0;
|
|
#endif
|
|
|
|
if (gc_flags & GC_HAS_DESTRUCTORS) {
|
|
GC_TRACE("Calling destructors");
|
|
if (EG(objects_store).object_buckets) {
|
|
/* Remember reference counters before calling destructors */
|
|
current = to_free.next;
|
|
while (current != &to_free) {
|
|
current->refcount = GC_REFCOUNT(current->ref);
|
|
current = current->next;
|
|
}
|
|
|
|
/* Call destructors */
|
|
current = to_free.next;
|
|
while (current != &to_free) {
|
|
p = current->ref;
|
|
GC_G(next_to_free) = current->next;
|
|
if ((GC_TYPE(p) & GC_TYPE_MASK) == IS_OBJECT) {
|
|
zend_object *obj = (zend_object*)p;
|
|
|
|
if (IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle]) &&
|
|
!(GC_FLAGS(obj) & IS_OBJ_DESTRUCTOR_CALLED)) {
|
|
GC_TRACE_REF(obj, "calling destructor");
|
|
GC_FLAGS(obj) |= IS_OBJ_DESTRUCTOR_CALLED;
|
|
if (obj->handlers->dtor_obj) {
|
|
GC_REFCOUNT(obj)++;
|
|
obj->handlers->dtor_obj(obj);
|
|
GC_REFCOUNT(obj)--;
|
|
}
|
|
}
|
|
}
|
|
current = GC_G(next_to_free);
|
|
}
|
|
|
|
/* Remove values captured in destructors */
|
|
current = to_free.next;
|
|
while (current != &to_free) {
|
|
GC_G(next_to_free) = current->next;
|
|
if (GC_REFCOUNT(current->ref) > current->refcount) {
|
|
gc_remove_nested_data_from_buffer(current->ref, current);
|
|
}
|
|
current = GC_G(next_to_free);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Destroy zvals */
|
|
GC_TRACE("Destroying zvals");
|
|
GC_G(gc_active) = 1;
|
|
current = to_free.next;
|
|
while (current != &to_free) {
|
|
p = current->ref;
|
|
GC_G(next_to_free) = current->next;
|
|
GC_TRACE_REF(p, "destroying");
|
|
if ((GC_TYPE(p) & GC_TYPE_MASK) == IS_OBJECT) {
|
|
zend_object *obj = (zend_object*)p;
|
|
|
|
if (EG(objects_store).object_buckets &&
|
|
IS_OBJ_VALID(EG(objects_store).object_buckets[obj->handle])) {
|
|
EG(objects_store).object_buckets[obj->handle] = SET_OBJ_INVALID(obj);
|
|
GC_TYPE(obj) = IS_NULL;
|
|
if (!(GC_FLAGS(obj) & IS_OBJ_FREE_CALLED)) {
|
|
GC_FLAGS(obj) |= IS_OBJ_FREE_CALLED;
|
|
if (obj->handlers->free_obj) {
|
|
GC_REFCOUNT(obj)++;
|
|
obj->handlers->free_obj(obj);
|
|
GC_REFCOUNT(obj)--;
|
|
}
|
|
}
|
|
SET_OBJ_BUCKET_NUMBER(EG(objects_store).object_buckets[obj->handle], EG(objects_store).free_list_head);
|
|
EG(objects_store).free_list_head = obj->handle;
|
|
p = current->ref = (zend_refcounted*)(((char*)obj) - obj->handlers->offset);
|
|
}
|
|
} else if ((GC_TYPE(p) & GC_TYPE_MASK) == IS_ARRAY) {
|
|
zend_array *arr = (zend_array*)p;
|
|
|
|
GC_TYPE(arr) = IS_NULL;
|
|
zend_hash_destroy(arr);
|
|
}
|
|
current = GC_G(next_to_free);
|
|
}
|
|
|
|
/* Free objects */
|
|
current = to_free.next;
|
|
while (current != &to_free) {
|
|
next = current->next;
|
|
p = current->ref;
|
|
if (EXPECTED(current >= GC_G(buf) && current < GC_G(buf) + GC_ROOT_BUFFER_MAX_ENTRIES)) {
|
|
current->prev = GC_G(unused);
|
|
GC_G(unused) = current;
|
|
}
|
|
efree(p);
|
|
current = next;
|
|
}
|
|
|
|
while (additional_buffer != NULL) {
|
|
gc_additional_buffer *next = additional_buffer->next;
|
|
efree(additional_buffer);
|
|
additional_buffer = next;
|
|
}
|
|
|
|
GC_TRACE("Collection finished");
|
|
GC_G(collected) += count;
|
|
GC_G(next_to_free) = orig_next_to_free;
|
|
#if ZEND_GC_DEBUG
|
|
GC_G(gc_full) = orig_gc_full;
|
|
#endif
|
|
GC_G(gc_active) = 0;
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
/*
|
|
* Local variables:
|
|
* tab-width: 4
|
|
* c-basic-offset: 4
|
|
* indent-tabs-mode: t
|
|
* End:
|
|
*/
|