2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved.
4 * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
6 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
7 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
9 * Permission is hereby granted to use or copy this program
10 * for any purpose, provided the above notices are retained on all copies.
11 * Permission to modify the code and to distribute modified code is granted,
12 * provided the above notices are retained, and a notice that the code was
13 * modified is included with the above copyright notice.
15 /* Boehm, February 1, 1996 1:19 pm PST */
16 # define I_HIDE_POINTERS
17 # include "private/gc_pmark.h"
19 # ifdef FINALIZE_ON_DEMAND
20 int GC_finalize_on_demand
= 1;
22 int GC_finalize_on_demand
= 0;
25 # ifdef JAVA_FINALIZATION
26 int GC_java_finalization
= 1;
28 int GC_java_finalization
= 0;
31 /* Type of mark procedure used for marking from finalizable object. */
32 /* This procedure normally does not mark the object, only its */
34 typedef void finalization_mark_proc(/* ptr_t finalizable_obj_ptr */);
36 # define HASH3(addr,size,log_size) \
37 ((((word)(addr) >> 3) ^ ((word)(addr) >> (3+(log_size)))) \
39 #define HASH2(addr,log_size) HASH3(addr, 1 << log_size, log_size)
41 struct hash_chain_entry
{
43 struct hash_chain_entry
* next
;
46 unsigned GC_finalization_failures
= 0;
47 /* Number of finalization requests that failed for lack of memory. */
49 struct disappearing_link
{
50 struct hash_chain_entry prolog
;
51 # define dl_hidden_link prolog.hidden_key
52 /* Field to be cleared. */
53 # define dl_next(x) (struct disappearing_link *)((x) -> prolog.next)
54 # define dl_set_next(x,y) (x) -> prolog.next = (struct hash_chain_entry *)(y)
56 word dl_hidden_obj
; /* Pointer to object base */
60 struct disappearing_link
**head
;
66 static int GC_register_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
, GC_PTR obj
);
67 static int GC_unregister_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
);
69 static struct dl_hashtbl_s GC_dl_hashtbl
= {
70 /* head */ NULL
, /* log_size */ -1, /* entries */ 0 };
72 static struct dl_hashtbl_s GC_ll_hashtbl
= { NULL
, -1, 0 };
75 static struct finalizable_object
{
76 struct hash_chain_entry prolog
;
77 # define fo_hidden_base prolog.hidden_key
78 /* Pointer to object base. */
79 /* No longer hidden once object */
80 /* is on finalize_now queue. */
81 # define fo_next(x) (struct finalizable_object *)((x) -> prolog.next)
82 # define fo_set_next(x,y) (x) -> prolog.next = (struct hash_chain_entry *)(y)
83 GC_finalization_proc fo_fn
; /* Finalizer. */
85 word fo_object_size
; /* In bytes. */
86 finalization_mark_proc
* fo_mark_proc
; /* Mark-through procedure */
89 struct finalizable_object
* GC_finalize_now
= 0;
90 /* LIst of objects that should be finalized now. */
92 static signed_word log_fo_table_size
= -1;
94 word GC_fo_entries
= 0;
96 void GC_push_finalizer_structures
GC_PROTO((void))
98 GC_push_all((ptr_t
)(&GC_ll_hashtbl
.head
),
99 (ptr_t
)(&GC_ll_hashtbl
.head
) + sizeof(word
));
100 GC_push_all((ptr_t
)(&GC_dl_hashtbl
.head
),
101 (ptr_t
)(&GC_dl_hashtbl
.head
) + sizeof(word
));
102 GC_push_all((ptr_t
)(&fo_head
), (ptr_t
)(&fo_head
) + sizeof(word
));
103 GC_push_all((ptr_t
)(&GC_finalize_now
),
104 (ptr_t
)(&GC_finalize_now
) + sizeof(word
));
107 /* Double the size of a hash table. *size_ptr is the log of its current */
108 /* size. May be a noop. */
109 /* *table is a pointer to an array of hash headers. If we succeed, we */
110 /* update both *table and *log_size_ptr. */
111 /* Lock is held. Signals are disabled. */
112 void GC_grow_table(table
, log_size_ptr
)
113 struct hash_chain_entry
***table
;
114 signed_word
* log_size_ptr
;
117 register struct hash_chain_entry
*p
;
118 int log_old_size
= *log_size_ptr
;
119 register int log_new_size
= log_old_size
+ 1;
120 word old_size
= ((log_old_size
== -1)? 0: (1 << log_old_size
));
121 register word new_size
= 1 << log_new_size
;
122 struct hash_chain_entry
**new_table
= (struct hash_chain_entry
**)
123 GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE(
124 (size_t)new_size
* sizeof(struct hash_chain_entry
*), NORMAL
);
126 if (new_table
== 0) {
128 ABORT("Insufficient space for initial table allocation");
133 for (i
= 0; i
< old_size
; i
++) {
136 register ptr_t real_key
= (ptr_t
)REVEAL_POINTER(p
-> hidden_key
);
137 register struct hash_chain_entry
*next
= p
-> next
;
138 register int new_hash
= HASH3(real_key
, new_size
, log_new_size
);
140 p
-> next
= new_table
[new_hash
];
141 new_table
[new_hash
] = p
;
145 *log_size_ptr
= log_new_size
;
149 # if defined(__STDC__) || defined(__cplusplus)
150 int GC_register_disappearing_link(GC_PTR
* link
)
152 int GC_register_disappearing_link(link
)
158 base
= (ptr_t
)GC_base((GC_PTR
)link
);
160 ABORT("Bad arg to GC_register_disappearing_link");
161 return(GC_general_register_disappearing_link(link
, base
));
164 # if defined(__STDC__) || defined(__cplusplus)
165 int GC_general_register_disappearing_link(GC_PTR
* link
,
168 int GC_general_register_disappearing_link(link
, obj
)
173 return GC_register_disappearing_link_inner(&GC_dl_hashtbl
, link
, obj
);
176 # if defined(__STDC__) || defined(__cplusplus)
177 static int GC_register_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
,
180 static int GC_register_disappearing_link_inner(dl_hashtbl
, link
, obj
)
181 struct dl_hashtbl_s
*dl_hashtbl
186 struct disappearing_link
*curr_dl
;
188 struct disappearing_link
* new_dl
;
191 if ((word
)link
& (ALIGNMENT
-1))
192 ABORT("Bad arg to GC_general_register_disappearing_link");
197 if (dl_hashtbl
-> log_size
== -1
198 || dl_hashtbl
-> entries
> ((word
)1 << dl_hashtbl
-> log_size
)) {
202 GC_grow_table((struct hash_chain_entry
***)(&dl_hashtbl
-> head
),
203 &dl_hashtbl
-> log_size
);
205 if (GC_print_stats
) {
206 GC_printf1("Grew dl table to %lu entries\n",
207 (unsigned long)(1 << dl_hashtbl
-> log_size
));
214 index
= HASH2(link
, dl_hashtbl
-> log_size
);
215 curr_dl
= dl_hashtbl
-> head
[index
];
216 for (curr_dl
= dl_hashtbl
-> head
[index
]; curr_dl
!= 0; curr_dl
= dl_next(curr_dl
)) {
217 if (curr_dl
-> dl_hidden_link
== HIDE_POINTER(link
)) {
218 curr_dl
-> dl_hidden_obj
= HIDE_POINTER(obj
);
226 new_dl
= (struct disappearing_link
*)
227 GC_INTERNAL_MALLOC(sizeof(struct disappearing_link
),NORMAL
);
233 new_dl
= (struct disappearing_link
*)
234 GC_oom_fn(sizeof(struct disappearing_link
));
236 GC_finalization_failures
++;
239 /* It's not likely we'll make it here, but ... */
245 new_dl
-> dl_hidden_obj
= HIDE_POINTER(obj
);
246 new_dl
-> dl_hidden_link
= HIDE_POINTER(link
);
247 dl_set_next(new_dl
, dl_hashtbl
-> head
[index
]);
248 dl_hashtbl
-> head
[index
] = new_dl
;
249 dl_hashtbl
-> entries
++;
257 # if defined(__STDC__) || defined(__cplusplus)
258 int GC_unregister_disappearing_link(GC_PTR
* link
)
260 int GC_unregister_disappearing_link(link
)
264 return GC_unregister_disappearing_link_inner(&GC_dl_hashtbl
, link
);
267 # if defined(__STDC__) || defined(__cplusplus)
268 static int GC_unregister_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
)
270 static int GC_unregister_disappearing_link_inner(dl_hashtbl
, link
)
271 struct dl_hashtbl_s
*dl_hashtbl
;
275 struct disappearing_link
*curr_dl
, *prev_dl
;
281 index
= HASH2(link
, dl_hashtbl
->log_size
);
282 if (((unsigned long)link
& (ALIGNMENT
-1))) goto out
;
283 prev_dl
= 0; curr_dl
= dl_hashtbl
-> head
[index
];
284 while (curr_dl
!= 0) {
285 if (curr_dl
-> dl_hidden_link
== HIDE_POINTER(link
)) {
287 dl_hashtbl
-> head
[index
] = dl_next(curr_dl
);
289 dl_set_next(prev_dl
, dl_next(curr_dl
));
291 dl_hashtbl
-> entries
--;
295 dl_set_next(curr_dl
, 0);
297 GC_free((GC_PTR
)curr_dl
);
302 curr_dl
= dl_next(curr_dl
);
310 /* toggleref support */
313 GC_hidden_pointer weak_ref
;
316 static int (*GC_toggleref_callback
) (GC_PTR obj
);
317 static GCToggleRef
*GC_toggleref_array
;
318 static int GC_toggleref_array_size
;
319 static int GC_toggleref_array_capacity
;
323 GC_process_togglerefs (void)
326 int toggle_ref_counts
[3] = { 0, 0, 0 };
328 for (i
= w
= 0; i
< GC_toggleref_array_size
; ++i
) {
330 GCToggleRef r
= GC_toggleref_array
[i
];
337 obj
= REVEAL_POINTER (r
.weak_ref
);
341 res
= GC_toggleref_callback (obj
);
342 ++toggle_ref_counts
[res
];
347 GC_toggleref_array
[w
].strong_ref
= obj
;
348 GC_toggleref_array
[w
].weak_ref
= (GC_hidden_pointer
)NULL
;
352 GC_toggleref_array
[w
].strong_ref
= NULL
;
353 GC_toggleref_array
[w
].weak_ref
= HIDE_POINTER (obj
);
357 ABORT("Invalid callback result");
361 for (i
= w
; i
< GC_toggleref_array_size
; ++i
) {
362 GC_toggleref_array
[w
].strong_ref
= NULL
;
363 GC_toggleref_array
[w
].weak_ref
= (GC_hidden_pointer
)NULL
;
366 GC_toggleref_array_size
= w
;
369 /* Finalizer proc support */
370 static void (*GC_object_finalized_proc
) (GC_PTR obj
);
373 GC_set_finalizer_notify_proc (void (*proc
) (GC_PTR obj
))
375 GC_object_finalized_proc
= proc
;
379 static void push_and_mark_object (GC_PTR p
)
383 PUSH_OBJ((word
*)p
, hhdr
, GC_mark_stack_top
,
384 &(GC_mark_stack
[GC_mark_stack_size
]));
386 while (!GC_mark_stack_empty()) MARK_FROM_MARK_STACK();
388 if (GC_mark_state
!= MS_NONE
)
389 while (!GC_mark_some((ptr_t
)0)) {}
392 static void GC_mark_togglerefs ()
395 if (!GC_toggleref_array
)
398 GC_set_mark_bit ((GC_PTR
)GC_toggleref_array
);
399 for (i
= 0; i
< GC_toggleref_array_size
; ++i
) {
400 if (GC_toggleref_array
[i
].strong_ref
) {
401 GC_PTR object
= GC_toggleref_array
[i
].strong_ref
;
403 push_and_mark_object (object
);
408 static void GC_clear_togglerefs ()
411 for (i
= 0; i
< GC_toggleref_array_size
; ++i
) {
412 if (GC_toggleref_array
[i
].weak_ref
) {
413 GC_PTR object
= REVEAL_POINTER (GC_toggleref_array
[i
].weak_ref
);
415 if (!GC_is_marked (object
)) {
416 GC_toggleref_array
[i
].weak_ref
= (GC_hidden_pointer
)NULL
; /* We defer compaction to only happen on the callback step. */
418 /*No need to copy, boehm is non-moving */
426 void GC_toggleref_register_callback(int (*proccess_toggleref
) (GC_PTR obj
))
428 GC_toggleref_callback
= proccess_toggleref
;
432 ensure_toggleref_capacity (int capacity
)
434 if (!GC_toggleref_array
) {
435 GC_toggleref_array_capacity
= 32;
436 GC_toggleref_array
= (GCToggleRef
*) GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE (GC_toggleref_array_capacity
* sizeof (GCToggleRef
), NORMAL
);
438 if (GC_toggleref_array_size
+ capacity
>= GC_toggleref_array_capacity
) {
440 int old_capacity
= GC_toggleref_array_capacity
;
441 while (GC_toggleref_array_capacity
< GC_toggleref_array_size
+ capacity
)
442 GC_toggleref_array_capacity
*= 2;
444 tmp
= (GCToggleRef
*) GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE (GC_toggleref_array_capacity
* sizeof (GCToggleRef
), NORMAL
);
445 memcpy (tmp
, GC_toggleref_array
, GC_toggleref_array_size
* sizeof (GCToggleRef
));
446 GC_INTERNAL_FREE (GC_toggleref_array
);
447 GC_toggleref_array
= tmp
;
452 GC_toggleref_add (GC_PTR object
, int strong_ref
)
460 if (!GC_toggleref_callback
)
463 ensure_toggleref_capacity (1);
464 GC_toggleref_array
[GC_toggleref_array_size
].strong_ref
= strong_ref
? object
: NULL
;
465 GC_toggleref_array
[GC_toggleref_array_size
].weak_ref
= strong_ref
? (GC_hidden_pointer
)NULL
: HIDE_POINTER (object
);
466 ++GC_toggleref_array_size
;
477 # if defined(__STDC__) || defined(__cplusplus)
478 int GC_register_long_link(GC_PTR
* link
, GC_PTR obj
)
480 int GC_register_long_link(link
, obj
)
485 return GC_register_disappearing_link_inner(&GC_ll_hashtbl
, link
, obj
);
488 # if defined(__STDC__) || defined(__cplusplus)
489 int GC_unregister_long_link(GC_PTR
* link
)
491 int GC_unregister_long_link(link
)
495 return GC_unregister_disappearing_link_inner(&GC_ll_hashtbl
, link
);
498 /* Possible finalization_marker procedures. Note that mark stack */
499 /* overflow is handled by the caller, and is not a disaster. */
500 GC_API
void GC_normal_finalize_mark_proc(p
)
505 PUSH_OBJ((word
*)p
, hhdr
, GC_mark_stack_top
,
506 &(GC_mark_stack
[GC_mark_stack_size
]));
509 /* This only pays very partial attention to the mark descriptor. */
510 /* It does the right thing for normal and atomic objects, and treats */
511 /* most others as normal. */
512 GC_API
void GC_ignore_self_finalize_mark_proc(p
)
516 word descr
= hhdr
-> hb_descr
;
519 ptr_t target_limit
= p
+ WORDS_TO_BYTES(hhdr
-> hb_sz
) - 1;
521 if ((descr
& GC_DS_TAGS
) == GC_DS_LENGTH
) {
522 scan_limit
= p
+ descr
- sizeof(word
);
524 scan_limit
= target_limit
+ 1 - sizeof(word
);
526 for (q
= p
; q
<= scan_limit
; q
+= ALIGNMENT
) {
528 if (r
< p
|| r
> target_limit
) {
529 GC_PUSH_ONE_HEAP((word
)r
, q
);
535 GC_API
void GC_null_finalize_mark_proc(p
)
542 /* Register a finalization function. See gc.h for details. */
543 /* in the nonthreads case, we try to avoid disabling signals, */
544 /* since it can be expensive. Threads packages typically */
545 /* make it cheaper. */
546 /* The last parameter is a procedure that determines */
547 /* marking for finalization ordering. Any objects marked */
548 /* by that procedure will be guaranteed to not have been */
549 /* finalized when this finalizer is invoked. */
550 GC_API
void GC_register_finalizer_inner(obj
, fn
, cd
, ofn
, ocd
, mp
)
552 GC_finalization_proc fn
;
554 GC_finalization_proc
* ofn
;
556 finalization_mark_proc
* mp
;
559 struct finalizable_object
* curr_fo
, * prev_fo
;
561 struct finalizable_object
*new_fo
;
569 if (log_fo_table_size
== -1
570 || GC_fo_entries
> ((word
)1 << log_fo_table_size
)) {
574 GC_grow_table((struct hash_chain_entry
***)(&fo_head
),
577 if (GC_print_stats
) {
578 GC_printf1("Grew fo table to %lu entries\n",
579 (unsigned long)(1 << log_fo_table_size
));
586 /* in the THREADS case signals are disabled and we hold allocation */
587 /* lock; otherwise neither is true. Proceed carefully. */
589 index
= HASH2(base
, log_fo_table_size
);
590 prev_fo
= 0; curr_fo
= fo_head
[index
];
591 while (curr_fo
!= 0) {
592 if (curr_fo
-> fo_hidden_base
== HIDE_POINTER(base
)) {
593 /* Interruption by a signal in the middle of this */
594 /* should be safe. The client may see only *ocd */
595 /* updated, but we'll declare that to be his */
597 if (ocd
) *ocd
= (GC_PTR
) curr_fo
-> fo_client_data
;
598 if (ofn
) *ofn
= curr_fo
-> fo_fn
;
599 /* Delete the structure for base. */
601 fo_head
[index
] = fo_next(curr_fo
);
603 fo_set_next(prev_fo
, fo_next(curr_fo
));
607 /* May not happen if we get a signal. But a high */
608 /* estimate will only make the table larger than */
610 # if !defined(THREADS) && !defined(DBG_HDRS_ALL)
611 GC_free((GC_PTR
)curr_fo
);
614 curr_fo
-> fo_fn
= fn
;
615 curr_fo
-> fo_client_data
= (ptr_t
)cd
;
616 curr_fo
-> fo_mark_proc
= mp
;
617 /* Reinsert it. We deleted it first to maintain */
618 /* consistency in the event of a signal. */
620 fo_head
[index
] = curr_fo
;
622 fo_set_next(prev_fo
, curr_fo
);
632 curr_fo
= fo_next(curr_fo
);
645 /* We won't collect it, hence finalizer wouldn't be run. */
652 new_fo
= (struct finalizable_object
*)
653 GC_INTERNAL_MALLOC(sizeof(struct finalizable_object
),NORMAL
);
659 new_fo
= (struct finalizable_object
*)
660 GC_oom_fn(sizeof(struct finalizable_object
));
662 GC_finalization_failures
++;
665 /* It's not likely we'll make it here, but ... */
671 new_fo
-> fo_hidden_base
= (word
)HIDE_POINTER(base
);
672 new_fo
-> fo_fn
= fn
;
673 new_fo
-> fo_client_data
= (ptr_t
)cd
;
674 new_fo
-> fo_object_size
= hhdr
-> hb_sz
;
675 new_fo
-> fo_mark_proc
= mp
;
676 fo_set_next(new_fo
, fo_head
[index
]);
678 fo_head
[index
] = new_fo
;
685 # if defined(__STDC__)
686 void GC_register_finalizer(void * obj
,
687 GC_finalization_proc fn
, void * cd
,
688 GC_finalization_proc
*ofn
, void ** ocd
)
690 void GC_register_finalizer(obj
, fn
, cd
, ofn
, ocd
)
692 GC_finalization_proc fn
;
694 GC_finalization_proc
* ofn
;
698 GC_register_finalizer_inner(obj
, fn
, cd
, ofn
,
699 ocd
, GC_normal_finalize_mark_proc
);
702 # if defined(__STDC__)
703 void GC_register_finalizer_ignore_self(void * obj
,
704 GC_finalization_proc fn
, void * cd
,
705 GC_finalization_proc
*ofn
, void ** ocd
)
707 void GC_register_finalizer_ignore_self(obj
, fn
, cd
, ofn
, ocd
)
709 GC_finalization_proc fn
;
711 GC_finalization_proc
* ofn
;
715 GC_register_finalizer_inner(obj
, fn
, cd
, ofn
,
716 ocd
, GC_ignore_self_finalize_mark_proc
);
719 # if defined(__STDC__)
720 void GC_register_finalizer_no_order(void * obj
,
721 GC_finalization_proc fn
, void * cd
,
722 GC_finalization_proc
*ofn
, void ** ocd
)
724 void GC_register_finalizer_no_order(obj
, fn
, cd
, ofn
, ocd
)
726 GC_finalization_proc fn
;
728 GC_finalization_proc
* ofn
;
732 GC_register_finalizer_inner(obj
, fn
, cd
, ofn
,
733 ocd
, GC_null_finalize_mark_proc
);
738 static void GC_dump_finalization_links(struct dl_hashtbl_s
*dl_hashtbl
)
740 struct disappearing_link
*curr_dl
;
741 ptr_t real_ptr
, real_link
;
742 size_t dl_size
= dl_hashtbl
->log_size
== -1 ? 0 :
743 1 << dl_hashtbl
->log_size
;
746 for (i
= 0; i
< dl_size
; i
++) {
747 for (curr_dl
= dl_hashtbl
-> head
[i
]; curr_dl
!= 0;
748 curr_dl
= dl_next(curr_dl
)) {
749 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_obj
);
750 real_link
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_link
);
751 GC_printf2("Object: %lx, link: %lx\n", real_ptr
, real_link
);
756 void GC_dump_finalization()
758 struct finalizable_object
* curr_fo
;
760 int fo_size
= (log_fo_table_size
== -1 ) ? 0 : (1 << log_fo_table_size
);
763 GC_printf0("Disappearing (short) links:\n");
764 GC_dump_finalization_links(&GC_dl_hashtbl
);
765 GC_printf0("Disappearing long links:\n");
766 GC_dump_finalization_links(&GC_ll_hashtbl
);
768 GC_printf0("Finalizers:\n");
769 for (i
= 0; i
< fo_size
; i
++) {
770 for (curr_fo
= fo_head
[i
]; curr_fo
!= 0; curr_fo
= fo_next(curr_fo
)) {
771 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
772 GC_printf1("Finalizable object: 0x%lx\n", real_ptr
);
778 static void GC_make_disappearing_links_disappear(struct dl_hashtbl_s
*dl_hashtbl
)
780 struct disappearing_link
* curr_dl
, * prev_dl
, * next_dl
;
781 ptr_t real_ptr
, real_link
;
783 int dl_size
= (dl_hashtbl
-> log_size
== -1 ) ? 0 : (1 << dl_hashtbl
-> log_size
);
785 for (i
= 0; i
< dl_size
; i
++) {
786 curr_dl
= dl_hashtbl
-> head
[i
];
788 while (curr_dl
!= 0) {
789 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_obj
);
790 real_link
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_link
);
791 if (!GC_is_marked(real_ptr
)) {
792 *(word
*)real_link
= 0;
793 next_dl
= dl_next(curr_dl
);
795 dl_hashtbl
-> head
[i
] = next_dl
;
797 dl_set_next(prev_dl
, next_dl
);
799 GC_clear_mark_bit((ptr_t
)curr_dl
);
800 dl_hashtbl
-> entries
--;
804 curr_dl
= dl_next(curr_dl
);
810 static void GC_remove_dangling_disappearing_links(struct dl_hashtbl_s
*dl_hashtbl
)
812 struct disappearing_link
* curr_dl
, * prev_dl
, * next_dl
;
813 ptr_t real_ptr
, real_link
;
815 int dl_size
= (dl_hashtbl
-> log_size
== -1 ) ? 0 : (1 << dl_hashtbl
-> log_size
);
817 for (i
= 0; i
< dl_size
; i
++) {
818 curr_dl
= dl_hashtbl
-> head
[i
];
820 while (curr_dl
!= 0) {
821 real_link
= GC_base((ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_link
));
822 if (real_link
!= 0 && !GC_is_marked(real_link
)) {
823 next_dl
= dl_next(curr_dl
);
825 dl_hashtbl
-> head
[i
] = next_dl
;
827 dl_set_next(prev_dl
, next_dl
);
829 GC_clear_mark_bit((ptr_t
)curr_dl
);
830 dl_hashtbl
-> entries
--;
834 curr_dl
= dl_next(curr_dl
);
840 /* Called with world stopped. Cause disappearing links to disappear, */
841 /* and invoke finalizers. */
844 struct finalizable_object
* curr_fo
, * prev_fo
, * next_fo
;
847 int fo_size
= (log_fo_table_size
== -1 ) ? 0 : (1 << log_fo_table_size
);
849 GC_mark_togglerefs();
851 /* Make non-tracking disappearing links disappear */
852 GC_make_disappearing_links_disappear(&GC_dl_hashtbl
);
854 /* Mark all objects reachable via chains of 1 or more pointers */
855 /* from finalizable objects. */
856 GC_ASSERT(GC_mark_state
== MS_NONE
);
857 for (i
= 0; i
< fo_size
; i
++) {
858 for (curr_fo
= fo_head
[i
]; curr_fo
!= 0; curr_fo
= fo_next(curr_fo
)) {
859 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
860 if (!GC_is_marked(real_ptr
)) {
861 GC_MARKED_FOR_FINALIZATION(real_ptr
);
862 GC_MARK_FO(real_ptr
, curr_fo
-> fo_mark_proc
);
863 if (GC_is_marked(real_ptr
)) {
864 WARN("Finalization cycle involving %lx\n", real_ptr
);
869 /* Enqueue for finalization all objects that are still */
871 GC_words_finalized
= 0;
872 for (i
= 0; i
< fo_size
; i
++) {
873 curr_fo
= fo_head
[i
];
875 while (curr_fo
!= 0) {
876 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
877 if (!GC_is_marked(real_ptr
)) {
878 if (!GC_java_finalization
) {
879 GC_set_mark_bit(real_ptr
);
881 /* Delete from hash table */
882 next_fo
= fo_next(curr_fo
);
884 fo_head
[i
] = next_fo
;
886 fo_set_next(prev_fo
, next_fo
);
890 if (GC_object_finalized_proc
)
891 GC_object_finalized_proc (real_ptr
);
893 /* Add to list of objects awaiting finalization. */
894 fo_set_next(curr_fo
, GC_finalize_now
);
895 GC_finalize_now
= curr_fo
;
896 /* unhide object pointer so any future collections will */
898 curr_fo
-> fo_hidden_base
=
899 (word
) REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
900 GC_words_finalized
+=
901 ALIGNED_WORDS(curr_fo
-> fo_object_size
)
902 + ALIGNED_WORDS(sizeof(struct finalizable_object
));
903 GC_ASSERT(GC_is_marked(GC_base((ptr_t
)curr_fo
)));
907 curr_fo
= fo_next(curr_fo
);
912 if (GC_java_finalization
) {
913 /* make sure we mark everything reachable from objects finalized
914 using the no_order mark_proc */
915 for (curr_fo
= GC_finalize_now
;
916 curr_fo
!= NULL
; curr_fo
= fo_next(curr_fo
)) {
917 real_ptr
= (ptr_t
)curr_fo
-> fo_hidden_base
;
918 if (!GC_is_marked(real_ptr
)) {
919 if (curr_fo
-> fo_mark_proc
== GC_null_finalize_mark_proc
) {
920 GC_MARK_FO(real_ptr
, GC_normal_finalize_mark_proc
);
922 GC_set_mark_bit(real_ptr
);
927 /* Remove dangling disappearing links. */
928 GC_remove_dangling_disappearing_links(&GC_dl_hashtbl
);
930 GC_clear_togglerefs ();
932 /* Make long links disappear and remove dangling ones. */
933 GC_make_disappearing_links_disappear(&GC_ll_hashtbl
);
934 GC_remove_dangling_disappearing_links(&GC_ll_hashtbl
);
937 #ifndef JAVA_FINALIZATION_NOT_NEEDED
939 /* Enqueue all remaining finalizers to be run - Assumes lock is
940 * held, and signals are disabled */
941 void GC_enqueue_all_finalizers()
943 struct finalizable_object
* curr_fo
, * prev_fo
, * next_fo
;
948 fo_size
= (log_fo_table_size
== -1 ) ? 0 : (1 << log_fo_table_size
);
949 GC_words_finalized
= 0;
950 for (i
= 0; i
< fo_size
; i
++) {
951 curr_fo
= fo_head
[i
];
953 while (curr_fo
!= 0) {
954 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
955 GC_MARK_FO(real_ptr
, GC_normal_finalize_mark_proc
);
956 GC_set_mark_bit(real_ptr
);
958 /* Delete from hash table */
959 next_fo
= fo_next(curr_fo
);
961 fo_head
[i
] = next_fo
;
963 fo_set_next(prev_fo
, next_fo
);
967 /* Add to list of objects awaiting finalization. */
968 fo_set_next(curr_fo
, GC_finalize_now
);
969 GC_finalize_now
= curr_fo
;
971 /* unhide object pointer so any future collections will */
973 curr_fo
-> fo_hidden_base
=
974 (word
) REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
976 GC_words_finalized
+=
977 ALIGNED_WORDS(curr_fo
-> fo_object_size
)
978 + ALIGNED_WORDS(sizeof(struct finalizable_object
));
986 /* Invoke all remaining finalizers that haven't yet been run.
987 * This is needed for strict compliance with the Java standard,
988 * which can make the runtime guarantee that all finalizers are run.
989 * Unfortunately, the Java standard implies we have to keep running
990 * finalizers until there are no more left, a potential infinite loop.
992 * Note that this is even more dangerous than the usual Java
993 * finalizers, in that objects reachable from static variables
994 * may have been finalized when these finalizers are run.
995 * Finalizers run at this point must be prepared to deal with a
996 * mostly broken world.
997 * This routine is externally callable, so is called without
998 * the allocation lock.
1000 GC_API
void GC_finalize_all()
1006 while (GC_fo_entries
> 0) {
1007 GC_enqueue_all_finalizers();
1010 GC_INVOKE_FINALIZERS();
1019 /* Returns true if it is worth calling GC_invoke_finalizers. (Useful if */
1020 /* finalizers can only be called from some kind of `safe state' and */
1021 /* getting into that safe state is expensive.) */
1022 int GC_should_invoke_finalizers
GC_PROTO((void))
1024 return GC_finalize_now
!= 0;
1027 /* Invoke finalizers for all objects that are ready to be finalized. */
1028 /* Should be called without allocation lock. */
1029 int GC_invoke_finalizers()
1031 struct finalizable_object
* curr_fo
;
1033 word mem_freed_before
;
1036 while (GC_finalize_now
!= 0) {
1042 mem_freed_before
= GC_mem_freed
;
1044 curr_fo
= GC_finalize_now
;
1046 if (curr_fo
!= 0) GC_finalize_now
= fo_next(curr_fo
);
1049 if (curr_fo
== 0) break;
1051 GC_finalize_now
= fo_next(curr_fo
);
1053 fo_set_next(curr_fo
, 0);
1054 (*(curr_fo
-> fo_fn
))((ptr_t
)(curr_fo
-> fo_hidden_base
),
1055 curr_fo
-> fo_client_data
);
1056 curr_fo
-> fo_client_data
= 0;
1059 /* This is probably a bad idea. It throws off accounting if */
1060 /* nearly all objects are finalizable. O.w. it shouldn't */
1062 GC_free((GC_PTR
)curr_fo
);
1065 if (count
!= 0 && mem_freed_before
!= GC_mem_freed
) {
1067 GC_finalizer_mem_freed
+= (GC_mem_freed
- mem_freed_before
);
1073 void (* GC_finalizer_notifier
)() = (void (*) GC_PROTO((void)))0;
1075 static GC_word last_finalizer_notification
= 0;
1077 void GC_notify_or_invoke_finalizers
GC_PROTO((void))
1079 /* This is a convenient place to generate backtraces if appropriate, */
1080 /* since that code is not callable with the allocation lock. */
1081 # if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
1082 static word last_back_trace_gc_no
= 1; /* Skip first one. */
1084 if (GC_gc_no
> last_back_trace_gc_no
) {
1087 # ifdef KEEP_BACK_PTRS
1089 /* Stops when GC_gc_no wraps; that's OK. */
1090 last_back_trace_gc_no
= (word
)(-1); /* disable others. */
1091 for (i
= 0; i
< GC_backtraces
; ++i
) {
1092 /* FIXME: This tolerates concurrent heap mutation, */
1093 /* which may cause occasional mysterious results. */
1094 /* We need to release the GC lock, since GC_print_callers */
1095 /* acquires it. It probably shouldn't. */
1097 GC_generate_random_backtrace_no_gc();
1100 last_back_trace_gc_no
= GC_gc_no
;
1103 # ifdef MAKE_BACK_GRAPH
1104 if (GC_print_back_height
)
1105 GC_print_back_graph_stats();
1109 if (GC_finalize_now
== 0) return;
1110 if (!GC_finalize_on_demand
) {
1111 (void) GC_invoke_finalizers();
1113 GC_ASSERT(GC_finalize_now
== 0);
1114 # endif /* Otherwise GC can run concurrently and add more */
1117 if (GC_finalizer_notifier
!= (void (*) GC_PROTO((void)))0
1118 && last_finalizer_notification
!= GC_gc_no
) {
1119 last_finalizer_notification
= GC_gc_no
;
1120 GC_finalizer_notifier();
1125 GC_PTR
GC_call_with_alloc_lock(GC_fn_type fn
,
1128 GC_PTR
GC_call_with_alloc_lock(fn
, client_data
)
1141 result
= (*fn
)(client_data
);
1143 # ifndef GC_ASSERTIONS
1144 UNSET_LOCK_HOLDER();
1145 # endif /* o.w. UNLOCK() does it implicitly */
1152 #if !defined(NO_DEBUGGING)
1154 void GC_print_finalization_stats()
1156 struct finalizable_object
*fo
= GC_finalize_now
;
1159 GC_printf3("%lu finalization table entries; %lu/%lu short/long disappearing links alive\n",
1160 GC_fo_entries
, (unsigned long)GC_dl_hashtbl
.entries
, (unsigned long)GC_ll_hashtbl
.entries
);
1161 for (; 0 != fo
; fo
= fo_next(fo
)) ++ready
;
1162 GC_printf1("%lu objects are eligible for immediate finalization\n", ready
);
1165 #endif /* NO_DEBUGGING */