2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved.
4 * Copyright (c) 1998 by Silicon Graphics. All rights reserved.
5 * Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.
7 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
8 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
10 * Permission is hereby granted to use or copy this program
11 * for any purpose, provided the above notices are retained on all copies.
12 * Permission to modify the code and to distribute modified code is granted,
13 * provided the above notices are retained, and a notice that the code was
14 * modified is included with the above copyright notice.
19 # include "private/gc_priv.h"
22 # if !defined(MACOS) && !defined(MSWINCE)
24 # include <sys/types.h>
28 * Separate free lists are maintained for different sized objects
30 * The call GC_allocobj(i,k) ensures that the freelist for
31 * kind k objects of size i points to a non-empty
32 * free list. It returns a pointer to the first entry on the free list.
33 * In a single-threaded world, GC_allocobj may be called to allocate
34 * an object of (small) size i as follows:
36 * opp = &(GC_objfreelist[i]);
37 * if (*opp == 0) GC_allocobj(i, NORMAL);
39 * *opp = obj_link(ptr);
41 * Note that this is very fast if the free list is non-empty; it should
42 * only involve the execution of 4 or 5 simple instructions.
43 * All composite objects on freelists are cleared, except for
48 * The allocator uses GC_allochblk to allocate large chunks of objects.
49 * These chunks all start on addresses which are multiples of
50 * HBLKSZ. Each allocated chunk has an associated header,
51 * which can be located quickly based on the address of the chunk.
52 * (See headers.c for details.)
53 * This makes it possible to check quickly whether an
54 * arbitrary address corresponds to an object administered by the
58 word GC_non_gc_bytes
= 0; /* Number of bytes not intended to be collected */
63 int GC_incremental
= 0; /* By default, stop the world. */
66 int GC_parallel
= FALSE
; /* By default, parallel GC is off. */
68 int GC_full_freq
= 19; /* Every 20th collection is a full */
69 /* collection, whether we need it */
72 GC_bool GC_need_full_gc
= FALSE
;
73 /* Need full GC do to heap growth. */
76 GC_bool GC_world_stopped
= FALSE
;
77 # define IF_THREADS(x) x
79 # define IF_THREADS(x)
82 word GC_used_heap_size_after_full
= 0;
84 char * GC_copyright
[] =
85 {"Copyright 1988,1989 Hans-J. Boehm and Alan J. Demers ",
86 "Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. ",
87 "Copyright (c) 1996-1998 by Silicon Graphics. All rights reserved. ",
88 "Copyright (c) 1999-2001 by Hewlett-Packard Company. All rights reserved. ",
89 "THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY",
90 " EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK.",
91 "See source code for details." };
95 /* some more variables */
97 extern signed_word GC_mem_found
; /* Number of reclaimed longwords */
98 /* after garbage collection */
100 GC_bool GC_dont_expand
= 0;
102 word GC_free_space_divisor
= 3;
104 extern GC_bool
GC_collection_in_progress();
105 /* Collection is in progress, or was abandoned. */
107 extern GC_bool GC_print_back_height
;
109 int GC_never_stop_func
GC_PROTO((void)) { return(0); }
111 unsigned long GC_time_limit
= TIME_LIMIT
;
113 CLOCK_TYPE GC_start_time
; /* Time at which we stopped world. */
114 /* used only in GC_timeout_stop_func. */
116 int GC_n_attempts
= 0; /* Number of attempts at finishing */
117 /* collection within GC_time_limit. */
119 #if defined(SMALL_CONFIG) || defined(NO_CLOCK)
120 # define GC_timeout_stop_func GC_never_stop_func
122 int GC_timeout_stop_func
GC_PROTO((void))
124 CLOCK_TYPE current_time
;
125 static unsigned count
= 0;
126 unsigned long time_diff
;
128 if ((count
++ & 3) != 0) return(0);
129 GET_TIME(current_time
);
130 time_diff
= MS_TIME_DIFF(current_time
,GC_start_time
);
131 if (time_diff
>= GC_time_limit
) {
133 if (GC_print_stats
) {
134 GC_printf0("Abandoning stopped marking after ");
135 GC_printf1("%lu msecs", (unsigned long)time_diff
);
136 GC_printf1("(attempt %ld)\n", (unsigned long) GC_n_attempts
);
143 #endif /* !SMALL_CONFIG */
145 /* Return the minimum number of words that must be allocated between */
146 /* collections to amortize the collection cost. */
147 static word
min_words_allocd()
150 /* We punt, for now. */
151 register signed_word stack_size
= 10000;
154 register signed_word stack_size
= (ptr_t
)(&dummy
) - GC_stackbottom
;
156 word total_root_size
; /* includes double stack size, */
157 /* since the stack is expensive */
159 word scan_size
; /* Estimate of memory to be scanned */
160 /* during normal GC. */
162 if (stack_size
< 0) stack_size
= -stack_size
;
163 total_root_size
= 2 * stack_size
+ GC_root_size
;
164 scan_size
= BYTES_TO_WORDS(GC_heapsize
- GC_large_free_bytes
165 + (GC_large_free_bytes
>> 2)
166 /* use a bit more of large empty heap */
168 if (TRUE_INCREMENTAL
) {
169 return scan_size
/ (2 * GC_free_space_divisor
);
171 return scan_size
/ GC_free_space_divisor
;
175 /* Return the number of words allocated, adjusted for explicit storage */
176 /* management, etc.. This number is used in deciding when to trigger */
178 word
GC_adj_words_allocd()
180 register signed_word result
;
181 register signed_word expl_managed
=
182 BYTES_TO_WORDS((long)GC_non_gc_bytes
183 - (long)GC_non_gc_bytes_at_gc
);
185 /* Don't count what was explicitly freed, or newly allocated for */
186 /* explicit management. Note that deallocating an explicitly */
187 /* managed object should not alter result, assuming the client */
188 /* is playing by the rules. */
189 result
= (signed_word
)GC_words_allocd
190 - (signed_word
)GC_mem_freed
191 + (signed_word
)GC_finalizer_mem_freed
- expl_managed
;
192 if (result
> (signed_word
)GC_words_allocd
) {
193 result
= GC_words_allocd
;
194 /* probably client bug or unfortunate scheduling */
196 result
+= GC_words_finalized
;
197 /* We count objects enqueued for finalization as though they */
198 /* had been reallocated this round. Finalization is user */
199 /* visible progress. And if we don't count this, we have */
200 /* stability problems for programs that finalize all objects. */
201 result
+= GC_words_wasted
;
202 /* This doesn't reflect useful work. But if there is lots of */
203 /* new fragmentation, the same is probably true of the heap, */
204 /* and the collection will be correspondingly cheaper. */
205 if (result
< (signed_word
)(GC_words_allocd
>> 3)) {
206 /* Always count at least 1/8 of the allocations. We don't want */
207 /* to collect too infrequently, since that would inhibit */
208 /* coalescing of free storage blocks. */
209 /* This also makes us partially robust against client bugs. */
210 return(GC_words_allocd
>> 3);
217 /* Clear up a few frames worth of garbage left at the top of the stack. */
218 /* This is used to prevent us from accidentally treating garbade left */
219 /* on the stack by other parts of the collector as roots. This */
220 /* differs from the code in misc.c, which actually tries to keep the */
221 /* stack clear of long-lived, client-generated garbage. */
222 void GC_clear_a_few_frames()
228 for (i
= 0; i
< NWORDS
; i
++) frames
[i
] = 0;
231 /* Heap size at which we need a collection to avoid expanding past */
232 /* limits used by blacklisting. */
233 static word GC_collect_at_heapsize
= (word
)(-1);
235 /* Have we allocated enough to amortize a collection? */
236 GC_bool
GC_should_collect()
238 return(GC_adj_words_allocd() >= min_words_allocd()
239 || GC_heapsize
>= GC_collect_at_heapsize
);
243 void GC_notify_full_gc()
245 if (GC_start_call_back
!= (void (*) GC_PROTO((void)))0) {
246 (*GC_start_call_back
)();
250 GC_bool GC_is_full_gc
= FALSE
;
253 * Initiate a garbage collection if appropriate.
255 * between partial, full, and stop-world collections.
256 * Assumes lock held, signals disabled.
260 static int n_partial_gcs
= 0;
262 if (GC_should_collect()) {
263 if (!GC_incremental
) {
268 # ifdef PARALLEL_MARK
269 GC_wait_for_reclaim();
271 if (GC_need_full_gc
|| n_partial_gcs
>= GC_full_freq
) {
273 if (GC_print_stats
) {
275 "***>Full mark for collection %lu after %ld allocd bytes\n",
276 (unsigned long) GC_gc_no
+1,
277 (long)WORDS_TO_BYTES(GC_words_allocd
));
280 GC_promote_black_lists();
281 (void)GC_reclaim_all((GC_stop_func
)0, TRUE
);
285 GC_is_full_gc
= TRUE
;
290 /* We try to mark with the world stopped. */
291 /* If we run out of time, this turns into */
292 /* incremental marking. */
294 if (GC_time_limit
!= GC_TIME_UNLIMITED
) { GET_TIME(GC_start_time
); }
296 if (GC_stopped_mark(GC_time_limit
== GC_TIME_UNLIMITED
?
297 GC_never_stop_func
: GC_timeout_stop_func
)) {
298 # ifdef SAVE_CALL_CHAIN
299 GC_save_callers(GC_last_stack
);
301 GC_finish_collection();
303 if (!GC_is_full_gc
) {
304 /* Count this as the first attempt */
313 * Stop the world garbage collection. Assumes lock held, signals disabled.
314 * If stop_func is not GC_never_stop_func, then abort if stop_func returns TRUE.
315 * Return TRUE if we successfully completed the collection.
317 GC_bool
GC_try_to_collect_inner(stop_func
)
318 GC_stop_func stop_func
;
321 CLOCK_TYPE start_time
, current_time
;
323 if (GC_dont_gc
) return FALSE
;
324 if (GC_incremental
&& GC_collection_in_progress()) {
326 if (GC_print_stats
) {
328 "GC_try_to_collect_inner: finishing collection in progress\n");
330 # endif /* CONDPRINT */
331 /* Just finish collection already in progress. */
332 while(GC_collection_in_progress()) {
333 if (stop_func()) return(FALSE
);
334 GC_collect_a_little_inner(1);
337 if (stop_func
== GC_never_stop_func
) GC_notify_full_gc();
339 if (GC_print_stats
) {
340 if (GC_print_stats
) GET_TIME(start_time
);
342 "Initiating full world-stop collection %lu after %ld allocd bytes\n",
343 (unsigned long) GC_gc_no
+1,
344 (long)WORDS_TO_BYTES(GC_words_allocd
));
347 GC_promote_black_lists();
348 /* Make sure all blocks have been reclaimed, so sweep routines */
349 /* don't see cleared mark bits. */
350 /* If we're guaranteed to finish, then this is unnecessary. */
351 /* In the find_leak case, we have to finish to guarantee that */
352 /* previously unmarked objects are not reported as leaks. */
353 # ifdef PARALLEL_MARK
354 GC_wait_for_reclaim();
356 if ((GC_find_leak
|| stop_func
!= GC_never_stop_func
)
357 && !GC_reclaim_all(stop_func
, FALSE
)) {
358 /* Aborted. So far everything is still consistent. */
361 GC_invalidate_mark_state(); /* Flush mark stack. */
363 # ifdef SAVE_CALL_CHAIN
364 GC_save_callers(GC_last_stack
);
366 GC_is_full_gc
= TRUE
;
367 if (!GC_stopped_mark(stop_func
)) {
368 if (!GC_incremental
) {
369 /* We're partially done and have no way to complete or use */
370 /* current work. Reestablish invariants as cheaply as */
372 GC_invalidate_mark_state();
373 GC_unpromote_black_lists();
374 } /* else we claim the world is already still consistent. We'll */
375 /* finish incrementally. */
378 GC_finish_collection();
379 # if defined(CONDPRINT)
380 if (GC_print_stats
) {
381 GET_TIME(current_time
);
382 GC_printf1("Complete collection took %lu msecs\n",
383 MS_TIME_DIFF(current_time
,start_time
));
392 * Perform n units of garbage collection work. A unit is intended to touch
393 * roughly GC_RATE pages. Every once in a while, we do more than that.
394 * This needa to be a fairly large number with our current incremental
395 * GC strategy, since otherwise we allocate too much during GC, and the
396 * cleanup gets expensive.
399 # define MAX_PRIOR_ATTEMPTS 1
400 /* Maximum number of prior attempts at world stop marking */
401 /* A value of 1 means that we finish the second time, no matter */
402 /* how long it takes. Doesn't count the initial root scan */
405 int GC_deficit
= 0; /* The number of extra calls to GC_mark_some */
406 /* that we have made. */
408 void GC_collect_a_little_inner(n
)
413 if (GC_dont_gc
) return;
414 if (GC_incremental
&& GC_collection_in_progress()) {
415 for (i
= GC_deficit
; i
< GC_RATE
*n
; i
++) {
416 if (GC_mark_some((ptr_t
)0)) {
417 /* Need to finish a collection */
418 # ifdef SAVE_CALL_CHAIN
419 GC_save_callers(GC_last_stack
);
421 # ifdef PARALLEL_MARK
422 GC_wait_for_reclaim();
424 if (GC_n_attempts
< MAX_PRIOR_ATTEMPTS
425 && GC_time_limit
!= GC_TIME_UNLIMITED
) {
426 GET_TIME(GC_start_time
);
427 if (!GC_stopped_mark(GC_timeout_stop_func
)) {
432 (void)GC_stopped_mark(GC_never_stop_func
);
434 GC_finish_collection();
438 if (GC_deficit
> 0) GC_deficit
-= GC_RATE
*n
;
439 if (GC_deficit
< 0) GC_deficit
= 0;
445 int GC_collect_a_little
GC_PROTO(())
452 GC_collect_a_little_inner(1);
453 result
= (int)GC_collection_in_progress();
456 if (!result
&& GC_debugging_started
) GC_print_all_smashed();
461 * Assumes lock is held, signals are disabled.
463 * If stop_func() ever returns TRUE, we may fail and return FALSE.
464 * Increment GC_gc_no if we succeed.
466 GC_bool
GC_stopped_mark(stop_func
)
467 GC_stop_func stop_func
;
471 # if defined(PRINTTIMES) || defined(CONDPRINT)
472 CLOCK_TYPE start_time
, current_time
;
476 GET_TIME(start_time
);
478 # if defined(CONDPRINT) && !defined(PRINTTIMES)
479 if (GC_print_stats
) GET_TIME(start_time
);
481 # if defined(REGISTER_LIBRARIES_EARLY)
482 GC_cond_register_dynamic_libraries();
485 IF_THREADS(GC_world_stopped
= TRUE
);
487 if (GC_print_stats
) {
488 GC_printf1("--> Marking for collection %lu ",
489 (unsigned long) GC_gc_no
+ 1);
490 GC_printf2("after %lu allocd bytes + %lu wasted bytes\n",
491 (unsigned long) WORDS_TO_BYTES(GC_words_allocd
),
492 (unsigned long) WORDS_TO_BYTES(GC_words_wasted
));
495 # ifdef MAKE_BACK_GRAPH
496 if (GC_print_back_height
) {
497 GC_build_back_graph();
501 /* Mark from all roots. */
502 /* Minimize junk left in my registers and on the stack */
503 GC_clear_a_few_frames();
504 GC_noop(0,0,0,0,0,0);
507 if ((*stop_func
)()) {
509 if (GC_print_stats
) {
510 GC_printf0("Abandoned stopped marking after ");
511 GC_printf1("%lu iterations\n",
515 GC_deficit
= i
; /* Give the mutator a chance. */
516 IF_THREADS(GC_world_stopped
= FALSE
);
520 if (GC_mark_some((ptr_t
)(&dummy
))) break;
525 GC_printf2("Collection %lu reclaimed %ld bytes",
526 (unsigned long) GC_gc_no
- 1,
527 (long)WORDS_TO_BYTES(GC_mem_found
));
530 if (GC_print_stats
) {
531 GC_printf1("Collection %lu finished", (unsigned long) GC_gc_no
- 1);
534 # endif /* !PRINTSTATS */
536 if (GC_print_stats
) {
537 GC_printf1(" ---> heapsize = %lu bytes\n",
538 (unsigned long) GC_heapsize
);
539 /* Printf arguments may be pushed in funny places. Clear the */
543 # endif /* CONDPRINT */
545 /* Check all debugged objects for consistency */
546 if (GC_debugging_started
) {
550 IF_THREADS(GC_world_stopped
= FALSE
);
553 GET_TIME(current_time
);
554 GC_printf1("World-stopped marking took %lu msecs\n",
555 MS_TIME_DIFF(current_time
,start_time
));
558 if (GC_print_stats
) {
559 GET_TIME(current_time
);
560 GC_printf1("World-stopped marking took %lu msecs\n",
561 MS_TIME_DIFF(current_time
,start_time
));
568 /* Set all mark bits for the free list whose first entry is q */
570 void GC_set_fl_marks(ptr_t q
)
572 void GC_set_fl_marks(q
)
577 struct hblk
* h
, * last_h
= 0;
581 for (p
= q
; p
!= 0; p
= obj_link(p
)){
587 word_no
= (((word
*)p
) - ((word
*)h
));
588 set_mark_bit_from_hdr(hhdr
, word_no
);
592 /* Clear all mark bits for the free list whose first entry is q */
593 /* Decrement GC_mem_found by number of words on free list. */
595 void GC_clear_fl_marks(ptr_t q
)
597 void GC_clear_fl_marks(q
)
602 struct hblk
* h
, * last_h
= 0;
606 for (p
= q
; p
!= 0; p
= obj_link(p
)){
612 word_no
= (((word
*)p
) - ((word
*)h
));
613 clear_mark_bit_from_hdr(hhdr
, word_no
);
615 GC_mem_found
-= hhdr
-> hb_sz
;
620 /* Finish up a collection. Assumes lock is held, signals are disabled, */
621 /* but the world is otherwise running. */
622 void GC_finish_collection()
625 CLOCK_TYPE start_time
;
626 CLOCK_TYPE finalize_time
;
627 CLOCK_TYPE done_time
;
629 GET_TIME(start_time
);
630 finalize_time
= start_time
;
636 # if defined(LINUX) && defined(__ELF__) && !defined(SMALL_CONFIG)
637 if (getenv("GC_PRINT_ADDRESS_MAP") != 0) {
638 GC_print_address_map();
643 /* Mark all objects on the free list. All objects should be */
644 /* marked when we're done. */
646 register word size
; /* current object size */
650 for (kind
= 0; kind
< GC_n_kinds
; kind
++) {
651 for (size
= 1; size
<= MAXOBJSZ
; size
++) {
652 q
= GC_obj_kinds
[kind
].ok_freelist
[size
];
653 if (q
!= 0) GC_set_fl_marks(q
);
657 GC_start_reclaim(TRUE
);
658 /* The above just checks; it doesn't really reclaim anything. */
662 # ifdef STUBBORN_ALLOC
663 GC_clean_changing_list();
667 GET_TIME(finalize_time
);
670 if (GC_print_back_height
) {
671 # ifdef MAKE_BACK_GRAPH
672 GC_traverse_back_graph();
674 # ifndef SMALL_CONFIG
675 GC_err_printf0("Back height not available: "
676 "Rebuild collector with -DMAKE_BACK_GRAPH\n");
681 /* Clear free list mark bits, in case they got accidentally marked */
682 /* (or GC_find_leak is set and they were intentionally marked). */
683 /* Also subtract memory remaining from GC_mem_found count. */
684 /* Note that composite objects on free list are cleared. */
685 /* Thus accidentally marking a free list is not a problem; only */
686 /* objects on the list itself will be marked, and that's fixed here. */
688 register word size
; /* current object size */
689 register ptr_t q
; /* pointer to current object */
692 for (kind
= 0; kind
< GC_n_kinds
; kind
++) {
693 for (size
= 1; size
<= MAXOBJSZ
; size
++) {
694 q
= GC_obj_kinds
[kind
].ok_freelist
[size
];
695 if (q
!= 0) GC_clear_fl_marks(q
);
702 GC_printf1("Bytes recovered before sweep - f.l. count = %ld\n",
703 (long)WORDS_TO_BYTES(GC_mem_found
));
705 /* Reconstruct free lists to contain everything not marked */
706 GC_start_reclaim(FALSE
);
708 GC_used_heap_size_after_full
= USED_HEAP_SIZE
;
709 GC_need_full_gc
= FALSE
;
712 BYTES_TO_WORDS(USED_HEAP_SIZE
- GC_used_heap_size_after_full
)
713 > min_words_allocd();
718 "Immediately reclaimed %ld bytes in heap of size %lu bytes",
719 (long)WORDS_TO_BYTES(GC_mem_found
),
720 (unsigned long)GC_heapsize
);
722 GC_printf1("(%lu unmapped)", GC_unmapped_bytes
);
725 "\n%lu (atomic) + %lu (composite) collectable bytes in use\n",
726 (unsigned long)WORDS_TO_BYTES(GC_atomic_in_use
),
727 (unsigned long)WORDS_TO_BYTES(GC_composite_in_use
));
731 GC_is_full_gc
= FALSE
;
732 /* Reset or increment counters for next cycle */
733 GC_words_allocd_before_gc
+= GC_words_allocd
;
734 GC_non_gc_bytes_at_gc
= GC_non_gc_bytes
;
738 GC_finalizer_mem_freed
= 0;
745 GC_printf2("Finalize + initiate sweep took %lu + %lu msecs\n",
746 MS_TIME_DIFF(finalize_time
,start_time
),
747 MS_TIME_DIFF(done_time
,finalize_time
));
751 /* Externally callable routine to invoke full, stop-world collection */
752 # if defined(__STDC__) || defined(__cplusplus)
753 int GC_try_to_collect(GC_stop_func stop_func
)
755 int GC_try_to_collect(stop_func
)
756 GC_stop_func stop_func
;
762 if (GC_debugging_started
) GC_print_all_smashed();
763 GC_INVOKE_FINALIZERS();
767 if (!GC_is_initialized
) GC_init_inner();
768 /* Minimize junk left in my registers */
769 GC_noop(0,0,0,0,0,0);
770 result
= (int)GC_try_to_collect_inner(stop_func
);
775 if (GC_debugging_started
) GC_print_all_smashed();
776 GC_INVOKE_FINALIZERS();
781 void GC_gcollect
GC_PROTO(())
783 (void)GC_try_to_collect(GC_never_stop_func
);
784 if (GC_have_errors
) GC_print_all_errors();
787 word GC_n_heap_sects
= 0; /* Number of sections currently in heap. */
790 * Use the chunk of memory starting at p of size bytes as part of the heap.
791 * Assumes p is HBLKSIZE aligned, and bytes is a multiple of HBLKSIZE.
793 void GC_add_to_heap(p
, bytes
)
800 if (GC_n_heap_sects
>= MAX_HEAP_SECTS
) {
801 ABORT("Too many heap sections: Increase MAXHINCR or MAX_HEAP_SECTS");
803 phdr
= GC_install_header(p
);
805 /* This is extremely unlikely. Can't add it. This will */
806 /* almost certainly result in a 0 return from the allocator, */
807 /* which is entirely appropriate. */
810 GC_heap_sects
[GC_n_heap_sects
].hs_start
= (ptr_t
)p
;
811 GC_heap_sects
[GC_n_heap_sects
].hs_bytes
= bytes
;
813 words
= BYTES_TO_WORDS(bytes
);
814 phdr
-> hb_sz
= words
;
815 phdr
-> hb_map
= (unsigned char *)1; /* A value != GC_invalid_map */
816 phdr
-> hb_flags
= 0;
818 GC_heapsize
+= bytes
;
819 if ((ptr_t
)p
<= (ptr_t
)GC_least_plausible_heap_addr
820 || GC_least_plausible_heap_addr
== 0) {
821 GC_least_plausible_heap_addr
= (GC_PTR
)((ptr_t
)p
- sizeof(word
));
822 /* Making it a little smaller than necessary prevents */
823 /* us from getting a false hit from the variable */
824 /* itself. There's some unintentional reflection */
827 if ((ptr_t
)p
+ bytes
>= (ptr_t
)GC_greatest_plausible_heap_addr
) {
828 GC_greatest_plausible_heap_addr
= (GC_PTR
)((ptr_t
)p
+ bytes
);
832 # if !defined(NO_DEBUGGING)
833 void GC_print_heap_sects()
837 GC_printf1("Total heap size: %lu\n", (unsigned long) GC_heapsize
);
838 for (i
= 0; i
< GC_n_heap_sects
; i
++) {
839 unsigned long start
= (unsigned long) GC_heap_sects
[i
].hs_start
;
840 unsigned long len
= (unsigned long) GC_heap_sects
[i
].hs_bytes
;
844 GC_printf3("Section %ld from 0x%lx to 0x%lx ", (unsigned long)i
,
845 start
, (unsigned long)(start
+ len
));
846 for (h
= (struct hblk
*)start
; h
< (struct hblk
*)(start
+ len
); h
++) {
847 if (GC_is_black_listed(h
, HBLKSIZE
)) nbl
++;
849 GC_printf2("%lu/%lu blacklisted\n", (unsigned long)nbl
,
850 (unsigned long)(len
/HBLKSIZE
));
855 GC_PTR GC_least_plausible_heap_addr
= (GC_PTR
)ONES
;
856 GC_PTR GC_greatest_plausible_heap_addr
= 0;
861 return(x
> y
? x
: y
);
867 return(x
< y
? x
: y
);
870 # if defined(__STDC__) || defined(__cplusplus)
871 void GC_set_max_heap_size(GC_word n
)
873 void GC_set_max_heap_size(n
)
880 GC_word GC_max_retries
= 0;
883 * this explicitly increases the size of the heap. It is used
884 * internally, but may also be invoked from GC_expand_hp by the user.
885 * The argument is in units of HBLKSIZE.
886 * Tiny values of n are rounded up.
887 * Returns FALSE on failure.
889 GC_bool
GC_expand_hp_inner(n
)
894 word expansion_slop
; /* Number of bytes by which we expect the */
895 /* heap to expand soon. */
897 if (n
< MINHINCR
) n
= MINHINCR
;
898 bytes
= n
* HBLKSIZE
;
899 /* Make sure bytes is a multiple of GC_page_size */
901 word mask
= GC_page_size
- 1;
906 if (GC_max_heapsize
!= 0 && GC_heapsize
+ bytes
> GC_max_heapsize
) {
907 /* Exceeded self-imposed limit */
910 space
= GET_MEM(bytes
);
913 if (GC_print_stats
) {
914 GC_printf1("Failed to expand heap by %ld bytes\n",
915 (unsigned long)bytes
);
921 if (GC_print_stats
) {
922 GC_printf2("Increasing heap size by %lu after %lu allocated bytes\n",
923 (unsigned long)bytes
,
924 (unsigned long)WORDS_TO_BYTES(GC_words_allocd
));
926 GC_printf1("Root size = %lu\n", GC_root_size
);
927 GC_print_block_list(); GC_print_hblkfreelist();
932 expansion_slop
= WORDS_TO_BYTES(min_words_allocd()) + 4*MAXHINCR
*HBLKSIZE
;
933 if (GC_last_heap_addr
== 0 && !((word
)space
& SIGNB
)
934 || GC_last_heap_addr
!= 0 && GC_last_heap_addr
< (ptr_t
)space
) {
935 /* Assume the heap is growing up */
936 GC_greatest_plausible_heap_addr
=
937 (GC_PTR
)GC_max((ptr_t
)GC_greatest_plausible_heap_addr
,
938 (ptr_t
)space
+ bytes
+ expansion_slop
);
940 /* Heap is growing down */
941 GC_least_plausible_heap_addr
=
942 (GC_PTR
)GC_min((ptr_t
)GC_least_plausible_heap_addr
,
943 (ptr_t
)space
- expansion_slop
);
945 # if defined(LARGE_CONFIG)
946 if (((ptr_t
)GC_greatest_plausible_heap_addr
<= (ptr_t
)space
+ bytes
947 || (ptr_t
)GC_least_plausible_heap_addr
>= (ptr_t
)space
)
948 && GC_heapsize
> 0) {
949 /* GC_add_to_heap will fix this, but ... */
950 WARN("Too close to address space limit: blacklisting ineffective\n", 0);
953 GC_prev_heap_addr
= GC_last_heap_addr
;
954 GC_last_heap_addr
= (ptr_t
)space
;
955 GC_add_to_heap(space
, bytes
);
956 /* Force GC before we are likely to allocate past expansion_slop */
957 GC_collect_at_heapsize
=
958 GC_heapsize
+ expansion_slop
- 2*MAXHINCR
*HBLKSIZE
;
959 # if defined(LARGE_CONFIG)
960 if (GC_collect_at_heapsize
< GC_heapsize
/* wrapped */)
961 GC_collect_at_heapsize
= (word
)(-1);
966 /* Really returns a bool, but it's externally visible, so that's clumsy. */
967 /* Arguments is in bytes. */
968 # if defined(__STDC__) || defined(__cplusplus)
969 int GC_expand_hp(size_t bytes
)
971 int GC_expand_hp(bytes
)
980 if (!GC_is_initialized
) GC_init_inner();
981 result
= (int)GC_expand_hp_inner(divHBLKSZ((word
)bytes
));
982 if (result
) GC_requested_heapsize
+= bytes
;
988 unsigned GC_fail_count
= 0;
989 /* How many consecutive GC/expansion failures? */
990 /* Reset by GC_allochblk. */
992 GC_bool
GC_collect_or_expand(needed_blocks
, ignore_off_page
)
994 GC_bool ignore_off_page
;
996 if (!GC_incremental
&& !GC_dont_gc
&&
997 (GC_dont_expand
&& GC_words_allocd
> 0 || GC_should_collect())) {
1000 word blocks_to_get
= GC_heapsize
/(HBLKSIZE
*GC_free_space_divisor
)
1003 if (blocks_to_get
> MAXHINCR
) {
1006 if (ignore_off_page
) {
1009 slop
= 2*divHBLKSZ(BL_LIMIT
);
1010 if (slop
> needed_blocks
) slop
= needed_blocks
;
1012 if (needed_blocks
+ slop
> MAXHINCR
) {
1013 blocks_to_get
= needed_blocks
+ slop
;
1015 blocks_to_get
= MAXHINCR
;
1018 if (!GC_expand_hp_inner(blocks_to_get
)
1019 && !GC_expand_hp_inner(needed_blocks
)) {
1020 if (GC_fail_count
++ < GC_max_retries
) {
1021 WARN("Out of Memory! Trying to continue ...\n", 0);
1022 GC_gcollect_inner();
1024 # if !defined(AMIGA) || !defined(GC_AMIGA_FASTALLOC)
1025 WARN("Out of Memory! Returning NIL!\n", 0);
1031 if (GC_fail_count
&& GC_print_stats
) {
1032 GC_printf0("Memory available again ...\n");
1041 * Make sure the object free list for sz is not empty.
1042 * Return a pointer to the first object on the free list.
1043 * The object MUST BE REMOVED FROM THE FREE LIST BY THE CALLER.
1044 * Assumes we hold the allocator lock and signals are disabled.
1047 ptr_t
GC_allocobj(sz
, kind
)
1051 ptr_t
* flh
= &(GC_obj_kinds
[kind
].ok_freelist
[sz
]);
1052 GC_bool tried_minor
= FALSE
;
1054 if (sz
== 0) return(0);
1058 /* Do our share of marking work */
1059 if(TRUE_INCREMENTAL
) GC_collect_a_little_inner(1);
1060 /* Sweep blocks for objects of this size */
1061 GC_continue_reclaim(sz
, kind
);
1064 GC_new_hblk(sz
, kind
);
1068 if (GC_incremental
&& GC_time_limit
== GC_TIME_UNLIMITED
1069 && ! tried_minor
) {
1070 GC_collect_a_little_inner(1);
1073 if (!GC_collect_or_expand((word
)1,FALSE
)) {
1081 /* Successful allocation; reset failure count. */