2 * sgen-marksweep.c: The Mark & Sweep major collector.
5 * Mark Probst <mark.probst@gmail.com>
7 * Copyright 2009-2010 Novell, Inc.
8 * Copyright (C) 2012 Xamarin Inc
10 * This library is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Library General Public
12 * License 2.0 as published by the Free Software Foundation;
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Library General Public License for more details.
19 * You should have received a copy of the GNU Library General Public
20 * License 2.0 along with this library; if not, write to the Free
21 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
31 #include "utils/mono-counters.h"
32 #include "utils/mono-semaphore.h"
33 #include "utils/mono-time.h"
34 #include "metadata/object-internals.h"
35 #include "metadata/profiler-private.h"
37 #include "metadata/sgen-gc.h"
38 #include "metadata/sgen-protocol.h"
39 #include "metadata/sgen-cardtable.h"
40 #include "metadata/sgen-memory-governor.h"
41 #include "metadata/sgen-layout-stats.h"
42 #include "metadata/gc-internal.h"
43 #include "metadata/sgen-pointer-queue.h"
44 #include "metadata/sgen-pinning.h"
45 #include "metadata/sgen-workers.h"
47 #define SGEN_HAVE_CONCURRENT_MARK
49 #define MS_BLOCK_SIZE (16*1024)
50 #define MS_BLOCK_SIZE_SHIFT 14
51 #define MAJOR_SECTION_SIZE MS_BLOCK_SIZE
52 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
55 * Don't allocate single blocks, but alloc a contingent of this many
56 * blocks in one swoop. This must be a power of two.
58 #define MS_BLOCK_ALLOC_NUM 32
61 * Number of bytes before the first object in a block. At the start
62 * of a block is the MSBlockHeader, then opional padding, then come
63 * the objects, so this must be >= sizeof (MSBlockHeader).
65 #define BLOCK_INFO_IN_HEADER
66 #define MS_BLOCK_SKIP ((sizeof (MSBlockHeader) + 15) & ~15)
68 #define MS_BLOCK_FREE (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
70 #define MS_NUM_MARK_WORDS ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
72 typedef struct _MSBlockInfo MSBlockInfo;
76 unsigned int pinned : 1;
77 unsigned int has_references : 1;
78 unsigned int has_pinned : 1; /* means cannot evacuate */
79 unsigned int is_to_space : 1;
80 unsigned int swept : 1;
81 #ifndef BLOCK_INFO_IN_HEADER
85 MSBlockInfo *next_free;
86 size_t pin_queue_first_entry;
87 size_t pin_queue_last_entry;
88 #ifdef SGEN_HAVE_CONCURRENT_MARK
89 guint8 *cardtable_mod_union;
91 mword mark_words [MS_NUM_MARK_WORDS];
94 #ifdef BLOCK_INFO_IN_HEADER
95 #define MS_BLOCK_FOR_BLOCK_INFO(b) ((char*)(b))
97 #define MS_BLOCK_FOR_BLOCK_INFO(b) ((b)->block)
100 #define MS_BLOCK_OBJ(b,i) (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (b)->obj_size * (i))
101 #define MS_BLOCK_OBJ_FOR_SIZE(b,i,obj_size) (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (obj_size) * (i))
102 #define MS_BLOCK_DATA_FOR_OBJ(o) ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
105 #ifdef BLOCK_INFO_IN_HEADER
112 #ifdef BLOCK_INFO_IN_HEADER
113 #define MS_BLOCK_FOR_OBJ(o) (&((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
115 #define MS_BLOCK_FOR_OBJ(o) (((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
118 /* object index will always be small */
119 #define MS_BLOCK_OBJ_INDEX(o,b) ((int)(((char*)(o) - (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP)) / (b)->obj_size))
121 //casting to int is fine since blocks are 32k
122 #define MS_CALC_MARK_BIT(w,b,o) do { \
123 int i = ((int)((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o)))) >> SGEN_ALLOC_ALIGN_BITS; \
124 if (sizeof (mword) == 4) { \
133 #define MS_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] & (ONE_P << (b)))
134 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (ONE_P << (b)))
136 #define MS_OBJ_ALLOCED(o,b) (*(void**)(o) && (*(char**)(o) < MS_BLOCK_FOR_BLOCK_INFO (b) || *(char**)(o) >= MS_BLOCK_FOR_BLOCK_INFO (b) + MS_BLOCK_SIZE))
138 #define MS_BLOCK_OBJ_SIZE_FACTOR (sqrt (2.0))
141 * This way we can lookup block object size indexes for sizes up to
142 * 256 bytes with a single load.
144 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES 32
146 static int *block_obj_sizes;
147 static int num_block_obj_sizes;
148 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
150 #define MS_BLOCK_FLAG_PINNED 1
151 #define MS_BLOCK_FLAG_REFS 2
153 #define MS_BLOCK_TYPE_MAX 4
155 static gboolean *evacuate_block_obj_sizes;
156 static float evacuation_threshold = 0.666f;
157 #ifdef SGEN_HAVE_CONCURRENT_MARK
158 static float concurrent_evacuation_threshold = 0.666f;
159 static gboolean want_evacuation = FALSE;
162 static gboolean lazy_sweep = TRUE;
163 static gboolean have_swept;
165 #ifdef SGEN_HAVE_CONCURRENT_MARK
166 static gboolean concurrent_mark;
169 #define BLOCK_IS_TAGGED_HAS_REFERENCES(bl) SGEN_POINTER_IS_TAGGED_1 ((bl))
170 #define BLOCK_TAG_HAS_REFERENCES(bl) SGEN_POINTER_TAG_1 ((bl))
171 #define BLOCK_UNTAG_HAS_REFERENCES(bl) SGEN_POINTER_UNTAG_1 ((bl))
173 #define BLOCK_TAG(bl) ((bl)->has_references ? BLOCK_TAG_HAS_REFERENCES ((bl)) : (bl))
175 /* all allocated blocks in the system */
176 static SgenPointerQueue allocated_blocks;
178 /* non-allocated block free-list */
179 static void *empty_blocks = NULL;
180 static size_t num_empty_blocks = 0;
182 #define FOREACH_BLOCK(bl) { size_t __index; for (__index = 0; __index < allocated_blocks.next_slot; ++__index) { (bl) = BLOCK_UNTAG_HAS_REFERENCES (allocated_blocks.data [__index]);
183 #define FOREACH_BLOCK_HAS_REFERENCES(bl,hr) { size_t __index; for (__index = 0; __index < allocated_blocks.next_slot; ++__index) { (bl) = allocated_blocks.data [__index]; (hr) = BLOCK_IS_TAGGED_HAS_REFERENCES ((bl)); (bl) = BLOCK_UNTAG_HAS_REFERENCES ((bl));
184 #define END_FOREACH_BLOCK } }
185 #define DELETE_BLOCK_IN_FOREACH() (allocated_blocks.data [__index] = NULL)
187 static size_t num_major_sections = 0;
188 /* one free block list for each block object size */
189 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
191 static long long stat_major_blocks_alloced = 0;
192 static long long stat_major_blocks_freed = 0;
193 static long long stat_major_blocks_lazy_swept = 0;
194 static long long stat_major_objects_evacuated = 0;
196 #if SIZEOF_VOID_P != 8
197 static long long stat_major_blocks_freed_ideal = 0;
198 static long long stat_major_blocks_freed_less_ideal = 0;
199 static long long stat_major_blocks_freed_individual = 0;
200 static long long stat_major_blocks_alloced_less_ideal = 0;
203 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
204 static long long num_major_objects_marked = 0;
205 #define INC_NUM_MAJOR_OBJECTS_MARKED() (++num_major_objects_marked)
207 #define INC_NUM_MAJOR_OBJECTS_MARKED()
210 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
211 static mono_mutex_t scanned_objects_list_lock;
212 static SgenPointerQueue scanned_objects_list;
215 add_scanned_object (void *ptr)
217 if (!binary_protocol_is_enabled ())
220 mono_mutex_lock (&scanned_objects_list_lock);
221 sgen_pointer_queue_add (&scanned_objects_list, ptr);
222 mono_mutex_unlock (&scanned_objects_list_lock);
227 sweep_block (MSBlockInfo *block, gboolean during_major_collection);
230 ms_find_block_obj_size_index (size_t size)
233 SGEN_ASSERT (9, size <= SGEN_MAX_SMALL_OBJ_SIZE, "size %d is bigger than max small object size %d", size, SGEN_MAX_SMALL_OBJ_SIZE);
234 for (i = 0; i < num_block_obj_sizes; ++i)
235 if (block_obj_sizes [i] >= size)
237 g_error ("no object of size %d\n", size);
240 #define FREE_BLOCKS_FROM(lists,p,r) (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
241 #define FREE_BLOCKS(p,r) (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
243 #define MS_BLOCK_OBJ_SIZE_INDEX(s) \
244 (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ? \
245 fast_block_obj_size_indexes [((s)+7)>>3] : \
246 ms_find_block_obj_size_index ((s)))
249 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
253 start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
255 start = sgen_alloc_os_memory (nursery_size, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
261 update_heap_boundaries_for_block (MSBlockInfo *block)
263 sgen_update_heap_boundaries ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), (mword)MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE);
267 ms_get_empty_block (void)
271 void *block, *empty, *next;
276 * We try allocating MS_BLOCK_ALLOC_NUM blocks first. If that's
277 * unsuccessful, we halve the number of blocks and try again, until we're at
278 * 1. If that doesn't work, either, we assert.
280 int alloc_num = MS_BLOCK_ALLOC_NUM;
282 p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * alloc_num, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE,
283 alloc_num == 1 ? "major heap section" : NULL);
289 for (i = 0; i < alloc_num; ++i) {
292 * We do the free list update one after the
293 * other so that other threads can use the new
294 * blocks as quickly as possible.
297 empty = empty_blocks;
298 *(void**)block = empty;
299 } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
303 SGEN_ATOMIC_ADD_P (num_empty_blocks, alloc_num);
305 stat_major_blocks_alloced += alloc_num;
306 #if SIZEOF_VOID_P != 8
307 if (alloc_num != MS_BLOCK_ALLOC_NUM)
308 stat_major_blocks_alloced_less_ideal += alloc_num;
313 empty = empty_blocks;
317 next = *(void**)block;
318 } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
320 SGEN_ATOMIC_ADD_P (num_empty_blocks, -1);
322 *(void**)block = NULL;
324 g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
330 ms_free_block (void *block)
334 sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
335 memset (block, 0, MS_BLOCK_SIZE);
338 empty = empty_blocks;
339 *(void**)block = empty;
340 } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
342 SGEN_ATOMIC_ADD_P (num_empty_blocks, 1);
345 //#define MARKSWEEP_CONSISTENCY_CHECK
347 #ifdef MARKSWEEP_CONSISTENCY_CHECK
349 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
353 for (; block; block = block->next_free) {
354 g_assert (block->obj_size == size);
355 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
357 /* blocks in the free lists must have at least
360 g_assert (block->free_list);
362 /* the block must be in the allocated_blocks array */
363 g_assert (sgen_pointer_queue_find (&allocated_blocks, BLOCK_TAG (block)) != (size_t)-1);
368 check_empty_blocks (void)
372 for (p = empty_blocks; p; p = *(void**)p)
374 g_assert (i == num_empty_blocks);
378 consistency_check (void)
383 /* check all blocks */
384 FOREACH_BLOCK (block) {
385 int count = MS_BLOCK_FREE / block->obj_size;
389 /* check block header */
390 g_assert (((MSBlockHeader*)block->block)->info == block);
392 /* count number of free slots */
393 for (i = 0; i < count; ++i) {
394 void **obj = (void**) MS_BLOCK_OBJ (block, i);
395 if (!MS_OBJ_ALLOCED (obj, block))
399 /* check free list */
400 for (free = block->free_list; free; free = (void**)*free) {
401 g_assert (MS_BLOCK_FOR_OBJ (free) == block);
404 g_assert (num_free == 0);
406 /* check all mark words are zero */
408 for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
409 g_assert (block->mark_words [i] == 0);
413 /* check free blocks */
414 for (i = 0; i < num_block_obj_sizes; ++i) {
416 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
417 check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
420 check_empty_blocks ();
425 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
427 int size = block_obj_sizes [size_index];
428 int count = MS_BLOCK_FREE / size;
430 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
434 if (!sgen_memgov_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
437 #ifdef BLOCK_INFO_IN_HEADER
438 info = (MSBlockInfo*)ms_get_empty_block ();
441 MSBlockHeader *header;
442 info = sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
443 info->block = ms_get_empty_block ();
444 header = (MSBlockHeader*)info->block;
449 SGEN_ASSERT (9, count >= 2, "block with %d objects, it must hold at least 2", count);
451 info->obj_size = size;
452 info->obj_size_index = size_index;
453 info->pinned = pinned;
454 info->has_references = has_references;
455 info->has_pinned = pinned;
457 * Blocks that are to-space are not evacuated from. During an major collection
458 * blocks are allocated for two reasons: evacuating objects from the nursery and
459 * evacuating them from major blocks marked for evacuation. In both cases we don't
460 * want further evacuation.
462 info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD);
464 #ifdef SGEN_HAVE_CONCURRENT_MARK
465 info->cardtable_mod_union = NULL;
468 update_heap_boundaries_for_block (info);
470 /* build free list */
471 obj_start = MS_BLOCK_FOR_BLOCK_INFO (info) + MS_BLOCK_SKIP;
472 info->free_list = (void**)obj_start;
473 /* we're skipping the last one - it must be nulled */
474 for (i = 0; i < count - 1; ++i) {
475 char *next_obj_start = obj_start + size;
476 *(void**)obj_start = next_obj_start;
477 obj_start = next_obj_start;
480 *(void**)obj_start = NULL;
482 info->next_free = free_blocks [size_index];
483 free_blocks [size_index] = info;
485 sgen_pointer_queue_add (&allocated_blocks, BLOCK_TAG (info));
487 ++num_major_sections;
492 obj_is_from_pinned_alloc (char *ptr)
496 FOREACH_BLOCK (block) {
497 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE)
498 return block->pinned;
504 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
509 block = free_blocks [size_index];
510 SGEN_ASSERT (9, block, "no free block to unlink from free_blocks %p size_index %d", free_blocks, size_index);
512 if (G_UNLIKELY (!block->swept)) {
513 stat_major_blocks_lazy_swept ++;
514 sweep_block (block, FALSE);
517 obj = block->free_list;
518 SGEN_ASSERT (9, obj, "block %p in free list had no available object to alloc from", block);
520 block->free_list = *(void**)obj;
521 if (!block->free_list) {
522 free_blocks [size_index] = block->next_free;
523 block->next_free = NULL;
530 alloc_obj (MonoVTable *vtable, size_t size, gboolean pinned, gboolean has_references)
532 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
533 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
536 if (!free_blocks [size_index]) {
537 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
541 obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
543 *(MonoVTable**)obj = vtable;
549 major_alloc_object (MonoVTable *vtable, size_t size, gboolean has_references)
551 return alloc_obj (vtable, size, FALSE, has_references);
555 * We're not freeing the block if it's empty. We leave that work for
556 * the next major collection.
558 * This is just called from the domain clearing code, which runs in a
559 * single thread and has the GC lock, so we don't need an extra lock.
562 free_object (char *obj, size_t size, gboolean pinned)
564 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
568 sweep_block (block, FALSE);
569 SGEN_ASSERT (9, (pinned && block->pinned) || (!pinned && !block->pinned), "free-object pinning mixup object %p pinned %d block %p pinned %d", obj, pinned, block, block->pinned);
570 SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p is already free", obj);
571 MS_CALC_MARK_BIT (word, bit, obj);
572 SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p has mark bit set");
573 if (!block->free_list) {
574 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
575 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
576 SGEN_ASSERT (9, !block->next_free, "block %p doesn't have a free-list of object but belongs to a free-list of blocks");
577 block->next_free = free_blocks [size_index];
578 free_blocks [size_index] = block;
580 memset (obj, 0, size);
581 *(void**)obj = block->free_list;
582 block->free_list = (void**)obj;
586 major_free_non_pinned_object (char *obj, size_t size)
588 free_object (obj, size, FALSE);
591 /* size is a multiple of SGEN_ALLOC_ALIGN */
593 major_alloc_small_pinned_obj (MonoVTable *vtable, size_t size, gboolean has_references)
597 res = alloc_obj (vtable, size, TRUE, has_references);
598 /*If we failed to alloc memory, we better try releasing memory
599 *as pinned alloc is requested by the runtime.
602 sgen_perform_collection (0, GENERATION_OLD, "pinned alloc failure", TRUE);
603 res = alloc_obj (vtable, size, TRUE, has_references);
609 free_pinned_object (char *obj, size_t size)
611 free_object (obj, size, TRUE);
615 * size is already rounded up and we hold the GC lock.
618 major_alloc_degraded (MonoVTable *vtable, size_t size)
621 size_t old_num_sections;
623 old_num_sections = num_major_sections;
625 obj = alloc_obj (vtable, size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
626 if (G_LIKELY (obj)) {
627 HEAVY_STAT (++stat_objects_alloced_degraded);
628 HEAVY_STAT (stat_bytes_alloced_degraded += size);
629 g_assert (num_major_sections >= old_num_sections);
630 sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
636 * obj is some object. If it's not in the major heap (i.e. if it's in
637 * the nursery or LOS), return FALSE. Otherwise return whether it's
638 * been marked or copied.
641 major_is_object_live (char *obj)
647 if (sgen_ptr_in_nursery (obj))
650 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
653 if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
656 /* now we know it's in a major block */
657 block = MS_BLOCK_FOR_OBJ (obj);
658 SGEN_ASSERT (9, !block->pinned, "block %p is pinned, BTW why is this bad?");
659 MS_CALC_MARK_BIT (word, bit, obj);
660 return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
664 major_ptr_is_in_non_pinned_space (char *ptr, char **start)
668 FOREACH_BLOCK (block) {
669 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) {
670 int count = MS_BLOCK_FREE / block->obj_size;
674 for (i = 0; i <= count; ++i) {
675 if (ptr >= MS_BLOCK_OBJ (block, i) && ptr < MS_BLOCK_OBJ (block, i + 1)) {
676 *start = MS_BLOCK_OBJ (block, i);
680 return !block->pinned;
687 major_iterate_objects (IterateObjectsFlags flags, IterateObjectCallbackFunc callback, void *data)
689 gboolean sweep = flags & ITERATE_OBJECTS_SWEEP;
690 gboolean non_pinned = flags & ITERATE_OBJECTS_NON_PINNED;
691 gboolean pinned = flags & ITERATE_OBJECTS_PINNED;
694 FOREACH_BLOCK (block) {
695 int count = MS_BLOCK_FREE / block->obj_size;
698 if (block->pinned && !pinned)
700 if (!block->pinned && !non_pinned)
702 if (sweep && lazy_sweep) {
703 sweep_block (block, FALSE);
704 SGEN_ASSERT (0, block->swept, "Block must be swept after sweeping");
707 for (i = 0; i < count; ++i) {
708 void **obj = (void**) MS_BLOCK_OBJ (block, i);
711 MS_CALC_MARK_BIT (word, bit, obj);
712 if (!MS_MARK_BIT (block, word, bit))
715 if (MS_OBJ_ALLOCED (obj, block))
716 callback ((char*)obj, block->obj_size, data);
722 major_is_valid_object (char *object)
726 FOREACH_BLOCK (block) {
730 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > object) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= object))
733 idx = MS_BLOCK_OBJ_INDEX (object, block);
734 obj = (char*)MS_BLOCK_OBJ (block, idx);
737 return MS_OBJ_ALLOCED (obj, block);
745 major_describe_pointer (char *ptr)
749 FOREACH_BLOCK (block) {
757 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > ptr) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= ptr))
760 SGEN_LOG (0, "major-ptr (block %p sz %d pin %d ref %d)\n",
761 MS_BLOCK_FOR_BLOCK_INFO (block), block->obj_size, block->pinned, block->has_references);
763 idx = MS_BLOCK_OBJ_INDEX (ptr, block);
764 obj = (char*)MS_BLOCK_OBJ (block, idx);
765 live = MS_OBJ_ALLOCED (obj, block);
766 vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
768 MS_CALC_MARK_BIT (w, b, obj);
769 marked = MS_MARK_BIT (block, w, b);
774 SGEN_LOG (0, "object");
776 SGEN_LOG (0, "dead-object");
779 SGEN_LOG (0, "interior-ptr offset %td", ptr - obj);
781 SGEN_LOG (0, "dead-interior-ptr offset %td", ptr - obj);
784 SGEN_LOG (0, " marked %d)\n", marked ? 1 : 0);
793 major_check_scan_starts (void)
798 major_dump_heap (FILE *heap_dump_file)
801 int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
802 int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
805 for (i = 0; i < num_block_obj_sizes; ++i)
806 slots_available [i] = slots_used [i] = 0;
808 FOREACH_BLOCK (block) {
809 int index = ms_find_block_obj_size_index (block->obj_size);
810 int count = MS_BLOCK_FREE / block->obj_size;
812 slots_available [index] += count;
813 for (i = 0; i < count; ++i) {
814 if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
815 ++slots_used [index];
819 fprintf (heap_dump_file, "<occupancies>\n");
820 for (i = 0; i < num_block_obj_sizes; ++i) {
821 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
822 block_obj_sizes [i], slots_available [i], slots_used [i]);
824 fprintf (heap_dump_file, "</occupancies>\n");
826 FOREACH_BLOCK (block) {
827 int count = MS_BLOCK_FREE / block->obj_size;
831 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
833 for (i = 0; i <= count; ++i) {
834 if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
839 sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), MS_BLOCK_FOR_BLOCK_INFO (block));
845 fprintf (heap_dump_file, "</section>\n");
849 #define LOAD_VTABLE SGEN_LOAD_VTABLE
851 #ifdef SGEN_MARK_ON_ENQUEUE
852 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,desc,block,queue) do { \
854 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
855 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
856 MS_SET_MARK_BIT ((block), __word, __bit); \
857 if (sgen_gc_descr_has_references (desc)) \
858 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
859 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
860 INC_NUM_MAJOR_OBJECTS_MARKED (); \
863 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do { \
865 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
866 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj); \
867 if (!MS_MARK_BIT ((block), __word, __bit)) { \
868 MS_SET_MARK_BIT ((block), __word, __bit); \
869 if (sgen_gc_descr_has_references (desc)) \
870 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
871 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
872 INC_NUM_MAJOR_OBJECTS_MARKED (); \
875 #define MS_PAR_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do { \
877 gboolean __was_marked; \
878 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj); \
879 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
880 MS_PAR_SET_MARK_BIT (__was_marked, (block), __word, __bit); \
881 if (!__was_marked) { \
882 if (sgen_gc_descr_has_references (desc)) \
883 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
884 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
885 INC_NUM_MAJOR_OBJECTS_MARKED (); \
889 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,desc,block,queue) do { \
891 SGEN_ASSERT (0, sgen_get_current_collection_generation () == GENERATION_OLD, "Can't majorly enqueue objects when doing minor collection"); \
892 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
893 if (MS_OBJ_ALLOCED ((obj), (block))) { \
894 if (sgen_gc_descr_has_references (desc)) { \
895 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
897 MS_SET_MARK_BIT ((block), __word, __bit); \
898 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
900 INC_NUM_MAJOR_OBJECTS_MARKED (); \
903 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do { \
905 SGEN_ASSERT (0, sgen_get_current_collection_generation () == GENERATION_OLD, "Can't majorly enqueue objects when doing minor collection"); \
906 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
907 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj); \
909 if (sgen_gc_descr_has_references (desc)) { \
910 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
912 MS_SET_MARK_BIT ((block), __word, __bit); \
913 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
915 INC_NUM_MAJOR_OBJECTS_MARKED (); \
921 pin_major_object (char *obj, SgenGrayQueue *queue)
925 #ifdef SGEN_HAVE_CONCURRENT_MARK
927 g_assert_not_reached ();
930 block = MS_BLOCK_FOR_OBJ (obj);
931 block->has_pinned = TRUE;
932 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
935 #include "sgen-major-copy-object.h"
937 #ifdef SGEN_HAVE_CONCURRENT_MARK
939 major_copy_or_mark_object_concurrent (void **ptr, void *obj, SgenGrayQueue *queue)
941 SGEN_ASSERT (9, sgen_concurrent_collection_in_progress (), "Why are we scanning concurrently when there's no concurrent collection on?");
942 SGEN_ASSERT (9, !sgen_workers_are_working () || sgen_is_worker_thread (mono_native_thread_id_get ()), "We must not scan from two threads at the same time!");
944 g_assert (!SGEN_OBJECT_IS_FORWARDED (obj));
946 if (!sgen_ptr_in_nursery (obj)) {
949 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
951 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
952 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
953 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
955 if (sgen_los_object_is_pinned (obj))
959 if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
960 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
961 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
965 sgen_los_pin_object (obj);
966 if (SGEN_OBJECT_HAS_REFERENCES (obj))
967 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
968 INC_NUM_MAJOR_OBJECTS_MARKED ();
975 major_copy_or_mark_object (void **ptr, void *obj, SgenGrayQueue *queue)
979 HEAVY_STAT (++stat_copy_object_called_major);
981 SGEN_ASSERT (9, !sgen_concurrent_collection_in_progress (), "Why are we scanning non-concurrently when there's a concurrent collection on?");
983 SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
984 SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
986 if (sgen_ptr_in_nursery (obj)) {
988 char *forwarded, *old_obj;
990 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
991 SGEN_UPDATE_REFERENCE (ptr, forwarded);
994 if (SGEN_OBJECT_IS_PINNED (obj))
997 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
998 if (sgen_nursery_is_to_space (obj))
1001 HEAVY_STAT (++stat_objects_copied_major);
1005 obj = copy_object_no_checks (obj, queue);
1006 if (G_UNLIKELY (old_obj == obj)) {
1007 /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
1008 if (!sgen_ptr_in_nursery (obj)) {
1010 block = MS_BLOCK_FOR_OBJ (obj);
1011 size_index = block->obj_size_index;
1012 evacuate_block_obj_sizes [size_index] = FALSE;
1013 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
1017 SGEN_UPDATE_REFERENCE (ptr, obj);
1020 * FIXME: See comment for copy_object_no_checks(). If
1021 * we have that, we can let the allocation function
1022 * give us the block info, too, and we won't have to
1025 * FIXME (2): We should rework this to avoid all those nursery checks.
1028 * For the split nursery allocator the object might
1029 * still be in the nursery despite having being
1030 * promoted, in which case we can't mark it.
1032 if (!sgen_ptr_in_nursery (obj)) {
1033 block = MS_BLOCK_FOR_OBJ (obj);
1034 MS_CALC_MARK_BIT (word, bit, obj);
1035 SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
1036 #ifndef SGEN_MARK_ON_ENQUEUE
1037 if (!SGEN_VTABLE_HAS_REFERENCES (LOAD_VTABLE (obj)))
1040 MS_SET_MARK_BIT (block, word, bit);
1041 binary_protocol_mark (obj, (gpointer)LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1049 * If we have don't have a fixed heap we cannot know
1050 * whether an object is in the LOS or in the small
1051 * object major heap without checking its size. To do
1052 * that, however, we need to know that we actually
1053 * have a valid object, not a forwarding pointer, so
1054 * we have to do this check first.
1056 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1057 SGEN_UPDATE_REFERENCE (ptr, forwarded);
1061 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
1063 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
1067 block = MS_BLOCK_FOR_OBJ (obj);
1068 size_index = block->obj_size_index;
1069 evacuate = evacuate_block_obj_sizes [size_index];
1071 if (evacuate && !block->has_pinned) {
1072 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1073 if (block->is_to_space)
1075 HEAVY_STAT (++stat_major_objects_evacuated);
1076 goto do_copy_object;
1078 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
1081 if (sgen_los_object_is_pinned (obj))
1083 binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1085 #ifdef ENABLE_DTRACE
1086 if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1087 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
1088 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
1092 #ifdef SGEN_MARK_ON_ENQUEUE
1093 sgen_los_pin_object (obj);
1095 if (SGEN_OBJECT_HAS_REFERENCES (obj))
1096 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
1102 major_copy_or_mark_object_canonical (void **ptr, SgenGrayQueue *queue)
1104 major_copy_or_mark_object (ptr, *ptr, queue);
1107 #ifdef SGEN_HAVE_CONCURRENT_MARK
1109 major_copy_or_mark_object_concurrent_canonical (void **ptr, SgenGrayQueue *queue)
1111 major_copy_or_mark_object_concurrent (ptr, *ptr, queue);
1116 major_get_and_reset_num_major_objects_marked (void)
1118 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
1119 long long num = num_major_objects_marked;
1120 num_major_objects_marked = 0;
1127 #include "sgen-major-scan-object.h"
1129 #ifdef SGEN_HAVE_CONCURRENT_MARK
1130 #define SCAN_FOR_CONCURRENT_MARK
1131 #include "sgen-major-scan-object.h"
1132 #undef SCAN_FOR_CONCURRENT_MARK
1135 #if !defined (FIXED_HEAP) && !defined (SGEN_PARALLEL_MARK)
1136 //#define USE_PREFETCH_QUEUE
1137 #define DESCRIPTOR_FAST_PATH
1139 #ifdef HEAVY_STATISTICS
1140 static long long stat_optimized_copy;
1141 static long long stat_optimized_copy_nursery;
1142 static long long stat_optimized_copy_nursery_forwarded;
1143 static long long stat_optimized_copy_nursery_pinned;
1144 #ifdef SGEN_MARK_ON_ENQUEUE
1145 static long long stat_optimized_copy_major;
1146 static long long stat_optimized_copy_major_small_fast;
1147 static long long stat_optimized_copy_major_small_slow;
1148 static long long stat_optimized_copy_major_large;
1150 static long long stat_optimized_major_mark;
1151 static long long stat_optimized_major_mark_small;
1152 static long long stat_optimized_major_mark_large;
1153 static long long stat_optimized_major_scan;
1154 static long long stat_optimized_major_scan_no_refs;
1155 #ifdef DESCRIPTOR_FAST_PATH
1156 static long long stat_optimized_major_scan_fast;
1157 static long long stat_optimized_major_scan_slow;
1160 static long long stat_drain_prefetch_fills;
1161 static long long stat_drain_prefetch_fill_failures;
1162 static long long stat_drain_loops;
1165 /* Returns whether the object is still in the nursery. */
1166 static inline MONO_ALWAYS_INLINE gboolean
1167 optimized_copy_or_mark_object (void **ptr, void *obj, SgenGrayQueue *queue)
1169 #ifdef SGEN_MARK_ON_ENQUEUE
1173 #ifdef HEAVY_STATISTICS
1174 ++stat_optimized_copy;
1178 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj)))
1179 desc = sgen_obj_get_descriptor_safe (forwarded);
1181 desc = sgen_obj_get_descriptor_safe (obj);
1183 sgen_descriptor_count_copied_object (desc);
1187 SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
1188 SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
1190 if (sgen_ptr_in_nursery (obj)) {
1191 #ifdef SGEN_MARK_ON_ENQUEUE
1194 char *forwarded, *old_obj;
1195 mword vtable_word = *(mword*)obj;
1197 HEAVY_STAT (++stat_optimized_copy_nursery);
1199 if (SGEN_VTABLE_IS_PINNED (vtable_word)) {
1200 HEAVY_STAT (++stat_optimized_copy_nursery_pinned);
1203 if ((forwarded = SGEN_VTABLE_IS_FORWARDED (vtable_word))) {
1204 HEAVY_STAT (++stat_optimized_copy_nursery_forwarded);
1206 return sgen_ptr_in_nursery (forwarded);
1209 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
1210 if (sgen_nursery_is_to_space (obj))
1215 obj = copy_object_no_checks (obj, queue);
1216 SGEN_ASSERT (0, old_obj != obj, "Cannot handle copy object failure.");
1217 HEAVY_STAT (++stat_objects_copied_major);
1220 if (sgen_ptr_in_nursery (obj))
1223 #ifdef SGEN_MARK_ON_ENQUEUE
1225 * FIXME: See comment for copy_object_no_checks(). If
1226 * we have that, we can let the allocation function
1227 * give us the block info, too, and we won't have to
1230 * FIXME (2): We should rework this to avoid all those nursery checks.
1233 * For the split nursery allocator the object might
1234 * still be in the nursery despite having being
1235 * promoted, in which case we can't mark it.
1237 block = MS_BLOCK_FOR_OBJ (obj);
1238 MS_CALC_MARK_BIT (word, bit, obj);
1239 SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
1240 MS_SET_MARK_BIT (block, word, bit);
1241 binary_protocol_mark (obj, (gpointer)LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1246 #ifdef SGEN_MARK_ON_ENQUEUE
1248 mword vtable_word = *(mword*)obj;
1249 mword desc = sgen_vtable_get_descriptor ((MonoVTable*)vtable_word);
1250 int type = desc & 7;
1252 HEAVY_STAT (++stat_optimized_copy_major);
1254 if ((forwarded = SGEN_VTABLE_IS_FORWARDED (vtable_word))) {
1255 HEAVY_STAT (++stat_optimized_copy_major_forwarded);
1260 if (type <= DESC_TYPE_MAX_SMALL_OBJ || SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj)) <= SGEN_MAX_SMALL_OBJ_SIZE) {
1264 #ifdef HEAVY_STATISTICS
1265 if (type <= DESC_TYPE_MAX_SMALL_OBJ)
1266 ++stat_optimized_copy_major_small_fast;
1268 ++stat_optimized_copy_major_small_slow;
1271 block = MS_BLOCK_FOR_OBJ (obj);
1272 size_index = block->obj_size_index;
1273 evacuate = evacuate_block_obj_sizes [size_index];
1275 if (evacuate && !block->has_pinned) {
1276 HEAVY_STAT (++stat_optimized_copy_major_small_evacuate);
1277 if (block->is_to_space)
1279 goto do_copy_object;
1282 MS_MARK_OBJECT_AND_ENQUEUE (obj, desc, block, queue);
1284 HEAVY_STAT (++stat_optimized_copy_major_large);
1286 if (sgen_los_object_is_pinned (obj))
1288 binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1290 sgen_los_pin_object (obj);
1291 if (SGEN_OBJECT_HAS_REFERENCES (obj))
1292 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
1296 GRAY_OBJECT_ENQUEUE (queue, obj, 0);
1303 sgen_gray_object_dequeue_fast (SgenGrayQueue *queue, char** obj, mword *desc) {
1304 GrayQueueEntry *cursor = queue->prefetch_cursor;
1305 GrayQueueEntry *const end = queue->prefetch + SGEN_GRAY_QUEUE_PREFETCH_SIZE;
1307 #ifdef SGEN_GRAY_QUEUE_HAVE_DESCRIPTORS
1308 *desc = cursor->desc;
1309 GRAY_OBJECT_DEQUEUE (queue, &cursor->obj, &cursor->desc);
1311 GRAY_OBJECT_DEQUEUE (queue, &cursor->obj, NULL);
1314 #if !defined (SGEN_MARK_ON_ENQUEUE) && defined (BLOCK_INFO_IN_HEADER)
1317 MSBlockInfo *block = (MSBlockInfo*)MS_BLOCK_DATA_FOR_OBJ (cursor->obj);
1318 MS_CALC_MARK_BIT (word, bit, cursor->obj);
1319 PREFETCH_WRITE (&block->mark_words [word]);
1323 PREFETCH_READ (cursor->obj);
1326 cursor = queue->prefetch;
1327 queue->prefetch_cursor = cursor;
1331 drain_gray_stack (ScanCopyContext ctx)
1333 SgenGrayQueue *queue = ctx.queue;
1335 SGEN_ASSERT (0, ctx.scan_func == major_scan_object, "Wrong scan function");
1337 #ifdef USE_PREFETCH_QUEUE
1338 HEAVY_STAT (++stat_drain_prefetch_fills);
1339 if (!sgen_gray_object_fill_prefetch (queue)) {
1340 HEAVY_STAT (++stat_drain_prefetch_fill_failures);
1350 HEAVY_STAT (++stat_drain_loops);
1352 #ifdef USE_PREFETCH_QUEUE
1353 sgen_gray_object_dequeue_fast (queue, &obj, &desc);
1355 HEAVY_STAT (++stat_drain_prefetch_fills);
1356 if (!sgen_gray_object_fill_prefetch (queue)) {
1357 HEAVY_STAT (++stat_drain_prefetch_fill_failures);
1363 GRAY_OBJECT_DEQUEUE (queue, &obj, &desc);
1368 #ifndef SGEN_GRAY_QUEUE_HAVE_DESCRIPTORS
1369 desc = sgen_obj_get_descriptor_safe (obj);
1373 #ifndef SGEN_MARK_ON_ENQUEUE
1374 HEAVY_STAT (++stat_optimized_major_mark);
1376 /* Mark object or, if already marked, don't process. */
1377 if (!sgen_ptr_in_nursery (obj)) {
1378 if (type <= DESC_TYPE_MAX_SMALL_OBJ || SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj)) <= SGEN_MAX_SMALL_OBJ_SIZE) {
1379 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1382 HEAVY_STAT (++stat_optimized_major_mark_small);
1384 MS_CALC_MARK_BIT (__word, __bit, (obj));
1385 if (MS_MARK_BIT ((block), __word, __bit))
1387 MS_SET_MARK_BIT ((block), __word, __bit);
1389 HEAVY_STAT (++stat_optimized_major_mark_large);
1391 if (sgen_los_object_is_pinned (obj))
1393 sgen_los_pin_object (obj);
1398 #ifdef HEAVY_STATISTICS
1399 ++stat_optimized_major_scan;
1400 if (!sgen_gc_descr_has_references (desc))
1401 ++stat_optimized_major_scan_no_refs;
1404 /* Now scan the object. */
1407 #define HANDLE_PTR(ptr,obj) do { \
1408 void *__old = *(ptr); \
1410 gboolean __still_in_nursery = optimized_copy_or_mark_object ((ptr), __old, queue); \
1411 if (G_UNLIKELY (__still_in_nursery && !sgen_ptr_in_nursery ((ptr)) && !SGEN_OBJECT_IS_CEMENTED (*(ptr)))) { \
1412 void *__copy = *(ptr); \
1413 sgen_add_to_global_remset ((ptr), __copy); \
1418 #ifdef DESCRIPTOR_FAST_PATH
1419 if (type == DESC_TYPE_LARGE_BITMAP) {
1420 OBJ_LARGE_BITMAP_FOREACH_PTR (desc, obj);
1421 #ifdef HEAVY_STATISTICS
1422 sgen_descriptor_count_scanned_object (desc);
1423 ++stat_optimized_major_scan_fast;
1429 #ifdef HEAVY_STATISTICS
1430 ++stat_optimized_major_scan_slow;
1431 sgen_descriptor_count_scanned_object (desc);
1433 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
1434 add_scanned_object (start);
1437 #include "sgen-scan-object.h"
1444 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
1446 void **entry, **end;
1447 int last_index = -1;
1449 if (block->pin_queue_first_entry == block->pin_queue_last_entry)
1452 block->has_pinned = TRUE;
1454 entry = sgen_pinning_get_entry (block->pin_queue_first_entry);
1455 end = sgen_pinning_get_entry (block->pin_queue_last_entry);
1457 for (; entry < end; ++entry) {
1458 int index = MS_BLOCK_OBJ_INDEX (*entry, block);
1460 SGEN_ASSERT (9, index >= 0 && index < MS_BLOCK_FREE / block->obj_size, "invalid object %p index %d max-index %d", *entry, index, MS_BLOCK_FREE / block->obj_size);
1461 if (index == last_index)
1463 obj = MS_BLOCK_OBJ (block, index);
1464 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (obj, sgen_obj_get_descriptor (obj), block, queue);
1470 sweep_block_for_size (MSBlockInfo *block, int count, int obj_size)
1474 for (obj_index = 0; obj_index < count; ++obj_index) {
1476 void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, obj_index, obj_size);
1478 MS_CALC_MARK_BIT (word, bit, obj);
1479 if (MS_MARK_BIT (block, word, bit)) {
1480 SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p not allocated", obj);
1482 /* an unmarked object */
1483 if (MS_OBJ_ALLOCED (obj, block)) {
1485 * FIXME: Merge consecutive
1486 * slots for lower reporting
1487 * overhead. Maybe memset
1488 * will also benefit?
1490 binary_protocol_empty (obj, obj_size);
1491 MONO_GC_MAJOR_SWEPT ((mword)obj, obj_size);
1492 memset (obj, 0, obj_size);
1494 *(void**)obj = block->free_list;
1495 block->free_list = obj;
1503 * Traverse BLOCK, freeing and zeroing unused objects.
1506 sweep_block (MSBlockInfo *block, gboolean during_major_collection)
1509 void *reversed = NULL;
1511 if (!during_major_collection)
1512 g_assert (!sgen_concurrent_collection_in_progress ());
1517 count = MS_BLOCK_FREE / block->obj_size;
1519 block->free_list = NULL;
1521 /* Use inline instances specialized to constant sizes, this allows the compiler to replace the memset calls with inline code */
1522 // FIXME: Add more sizes
1523 switch (block->obj_size) {
1525 sweep_block_for_size (block, count, 16);
1528 sweep_block_for_size (block, count, block->obj_size);
1532 /* reset mark bits */
1533 memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1535 /* Reverse free list so that it's in address order */
1537 while (block->free_list) {
1538 void *next = *(void**)block->free_list;
1539 *(void**)block->free_list = reversed;
1540 reversed = block->free_list;
1541 block->free_list = next;
1543 block->free_list = reversed;
1554 if (sizeof (mword) == sizeof (unsigned long))
1555 count += __builtin_popcountl (d);
1557 count += __builtin_popcount (d);
1573 /* statistics for evacuation */
1574 int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1575 int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1576 int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1578 #ifdef SGEN_HAVE_CONCURRENT_MARK
1579 mword total_evacuate_heap = 0;
1580 mword total_evacuate_saved = 0;
1583 for (i = 0; i < num_block_obj_sizes; ++i)
1584 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1586 /* clear all the free lists */
1587 for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1588 MSBlockInfo **free_blocks = free_block_lists [i];
1590 for (j = 0; j < num_block_obj_sizes; ++j)
1591 free_blocks [j] = NULL;
1594 /* traverse all blocks, free and zero unmarked objects */
1595 FOREACH_BLOCK (block) {
1597 gboolean have_live = FALSE;
1598 gboolean has_pinned;
1599 gboolean have_free = FALSE;
1603 obj_size_index = block->obj_size_index;
1605 has_pinned = block->has_pinned;
1606 block->has_pinned = block->pinned;
1608 block->is_to_space = FALSE;
1611 count = MS_BLOCK_FREE / block->obj_size;
1613 #ifdef SGEN_HAVE_CONCURRENT_MARK
1614 if (block->cardtable_mod_union) {
1615 sgen_free_internal_dynamic (block->cardtable_mod_union, CARDS_PER_BLOCK, INTERNAL_MEM_CARDTABLE_MOD_UNION);
1616 block->cardtable_mod_union = NULL;
1620 /* Count marked objects in the block */
1621 for (i = 0; i < MS_NUM_MARK_WORDS; ++i) {
1622 nused += bitcount (block->mark_words [i]);
1631 sweep_block (block, TRUE);
1635 ++num_blocks [obj_size_index];
1636 slots_used [obj_size_index] += nused;
1637 slots_available [obj_size_index] += count;
1641 * If there are free slots in the block, add
1642 * the block to the corresponding free list.
1645 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1646 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1647 block->next_free = free_blocks [index];
1648 free_blocks [index] = block;
1651 update_heap_boundaries_for_block (block);
1654 * Blocks without live objects are removed from the
1655 * block list and freed.
1657 DELETE_BLOCK_IN_FOREACH ();
1659 binary_protocol_empty (MS_BLOCK_OBJ (block, 0), (char*)MS_BLOCK_OBJ (block, count) - (char*)MS_BLOCK_OBJ (block, 0));
1660 #if defined (FIXED_HEAP) || defined (BLOCK_INFO_IN_HEADER)
1661 ms_free_block (block);
1663 ms_free_block (block->block);
1664 sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
1667 --num_major_sections;
1669 } END_FOREACH_BLOCK;
1670 sgen_pointer_queue_remove_nulls (&allocated_blocks);
1672 for (i = 0; i < num_block_obj_sizes; ++i) {
1673 float usage = (float)slots_used [i] / (float)slots_available [i];
1674 if (num_blocks [i] > 5 && usage < evacuation_threshold) {
1675 evacuate_block_obj_sizes [i] = TRUE;
1677 g_print ("slot size %d - %d of %d used\n",
1678 block_obj_sizes [i], slots_used [i], slots_available [i]);
1681 evacuate_block_obj_sizes [i] = FALSE;
1683 #ifdef SGEN_HAVE_CONCURRENT_MARK
1685 mword total_bytes = block_obj_sizes [i] * slots_available [i];
1686 total_evacuate_heap += total_bytes;
1687 if (evacuate_block_obj_sizes [i])
1688 total_evacuate_saved += total_bytes - block_obj_sizes [i] * slots_used [i];
1693 #ifdef SGEN_HAVE_CONCURRENT_MARK
1694 want_evacuation = (float)total_evacuate_saved / (float)total_evacuate_heap > (1 - concurrent_evacuation_threshold);
1706 static int count_pinned_ref;
1707 static int count_pinned_nonref;
1708 static int count_nonpinned_ref;
1709 static int count_nonpinned_nonref;
1712 count_nonpinned_callback (char *obj, size_t size, void *data)
1714 MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1716 if (vtable->klass->has_references)
1717 ++count_nonpinned_ref;
1719 ++count_nonpinned_nonref;
1723 count_pinned_callback (char *obj, size_t size, void *data)
1725 MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1727 if (vtable->klass->has_references)
1730 ++count_pinned_nonref;
1733 static G_GNUC_UNUSED void
1734 count_ref_nonref_objs (void)
1738 count_pinned_ref = 0;
1739 count_pinned_nonref = 0;
1740 count_nonpinned_ref = 0;
1741 count_nonpinned_nonref = 0;
1743 major_iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, count_nonpinned_callback, NULL);
1744 major_iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, count_pinned_callback, NULL);
1746 total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1748 g_print ("ref: %d pinned %d non-pinned non-ref: %d pinned %d non-pinned -- %.1f\n",
1749 count_pinned_ref, count_nonpinned_ref,
1750 count_pinned_nonref, count_nonpinned_nonref,
1751 (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1755 ms_calculate_block_obj_sizes (double factor, int *arr)
1757 double target_size = sizeof (MonoObject);
1762 int target_count = (int)ceil (MS_BLOCK_FREE / target_size);
1763 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1765 if (size != last_size) {
1767 arr [num_sizes] = size;
1772 target_size *= factor;
1773 } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1778 /* only valid during minor collections */
1779 static mword old_num_major_sections;
1782 major_start_nursery_collection (void)
1784 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1785 consistency_check ();
1788 old_num_major_sections = num_major_sections;
1792 major_finish_nursery_collection (void)
1794 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1795 consistency_check ();
1797 sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1801 major_start_major_collection (void)
1805 /* clear the free lists */
1806 for (i = 0; i < num_block_obj_sizes; ++i) {
1807 if (!evacuate_block_obj_sizes [i])
1810 free_block_lists [0][i] = NULL;
1811 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1814 // Sweep all unswept blocks
1818 MONO_GC_SWEEP_BEGIN (GENERATION_OLD, TRUE);
1820 FOREACH_BLOCK (block) {
1821 sweep_block (block, TRUE);
1822 } END_FOREACH_BLOCK;
1824 MONO_GC_SWEEP_END (GENERATION_OLD, TRUE);
1829 major_finish_major_collection (ScannedObjectCounts *counts)
1831 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
1832 if (binary_protocol_is_enabled ()) {
1833 counts->num_scanned_objects = scanned_objects_list.next_slot;
1835 sgen_pointer_queue_sort_uniq (&scanned_objects_list);
1836 counts->num_unique_scanned_objects = scanned_objects_list.next_slot;
1838 sgen_pointer_queue_clear (&scanned_objects_list);
1843 #if SIZEOF_VOID_P != 8
1845 compare_pointers (const void *va, const void *vb) {
1846 char *a = *(char**)va, *b = *(char**)vb;
1856 major_have_computer_minor_collection_allowance (void)
1858 size_t section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1860 g_assert (have_swept);
1862 #if SIZEOF_VOID_P != 8
1864 int i, num_empty_blocks_orig, num_blocks, arr_length;
1866 void **empty_block_arr;
1867 void **rebuild_next;
1871 * sgen_free_os_memory () asserts in mono_vfree () because windows doesn't like freeing the middle of
1872 * a VirtualAlloc ()-ed block.
1877 if (num_empty_blocks <= section_reserve)
1879 SGEN_ASSERT (0, num_empty_blocks > 0, "section reserve can't be negative");
1881 num_empty_blocks_orig = num_empty_blocks;
1882 empty_block_arr = (void**)sgen_alloc_internal_dynamic (sizeof (void*) * num_empty_blocks_orig,
1883 INTERNAL_MEM_MS_BLOCK_INFO_SORT, FALSE);
1884 if (!empty_block_arr)
1888 for (block = empty_blocks; block; block = *(void**)block)
1889 empty_block_arr [i++] = block;
1890 SGEN_ASSERT (0, i == num_empty_blocks, "empty block count wrong");
1892 sgen_qsort (empty_block_arr, num_empty_blocks, sizeof (void*), compare_pointers);
1895 * We iterate over the free blocks, trying to find MS_BLOCK_ALLOC_NUM
1896 * contiguous ones. If we do, we free them. If that's not enough to get to
1897 * section_reserve, we halve the number of contiguous blocks we're looking
1898 * for and have another go, until we're done with looking for pairs of
1899 * blocks, at which point we give up and go to the fallback.
1901 arr_length = num_empty_blocks_orig;
1902 num_blocks = MS_BLOCK_ALLOC_NUM;
1903 while (num_empty_blocks > section_reserve && num_blocks > 1) {
1908 for (i = 0; i < arr_length; ++i) {
1910 void *block = empty_block_arr [i];
1911 SGEN_ASSERT (0, block, "we're not shifting correctly");
1913 empty_block_arr [dest] = block;
1915 * This is not strictly necessary, but we're
1918 empty_block_arr [i] = NULL;
1927 SGEN_ASSERT (0, first >= 0 && d > first, "algorithm is wrong");
1929 if ((char*)block != ((char*)empty_block_arr [d-1]) + MS_BLOCK_SIZE) {
1934 if (d + 1 - first == num_blocks) {
1936 * We found num_blocks contiguous blocks. Free them
1937 * and null their array entries. As an optimization
1938 * we could, instead of nulling the entries, shift
1939 * the following entries over to the left, while
1943 sgen_free_os_memory (empty_block_arr [first], MS_BLOCK_SIZE * num_blocks, SGEN_ALLOC_HEAP);
1944 for (j = first; j <= d; ++j)
1945 empty_block_arr [j] = NULL;
1949 num_empty_blocks -= num_blocks;
1951 stat_major_blocks_freed += num_blocks;
1952 if (num_blocks == MS_BLOCK_ALLOC_NUM)
1953 stat_major_blocks_freed_ideal += num_blocks;
1955 stat_major_blocks_freed_less_ideal += num_blocks;
1960 SGEN_ASSERT (0, dest <= i && dest <= arr_length, "array length is off");
1962 SGEN_ASSERT (0, arr_length == num_empty_blocks, "array length is off");
1967 /* rebuild empty_blocks free list */
1968 rebuild_next = (void**)&empty_blocks;
1969 for (i = 0; i < arr_length; ++i) {
1970 void *block = empty_block_arr [i];
1971 SGEN_ASSERT (0, block, "we're missing blocks");
1972 *rebuild_next = block;
1973 rebuild_next = (void**)block;
1975 *rebuild_next = NULL;
1978 sgen_free_internal_dynamic (empty_block_arr, sizeof (void*) * num_empty_blocks_orig, INTERNAL_MEM_MS_BLOCK_INFO_SORT);
1981 SGEN_ASSERT (0, num_empty_blocks >= 0, "we freed more blocks than we had in the first place?");
1985 * This is our threshold. If there's not more empty than used blocks, we won't
1986 * release uncontiguous blocks, in fear of fragmenting the address space.
1988 if (num_empty_blocks <= num_major_sections)
1992 while (num_empty_blocks > section_reserve) {
1993 void *next = *(void**)empty_blocks;
1994 sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP);
1995 empty_blocks = next;
1997 * Needs not be atomic because this is running
2002 ++stat_major_blocks_freed;
2003 #if SIZEOF_VOID_P != 8
2004 ++stat_major_blocks_freed_individual;
2010 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
2014 FOREACH_BLOCK (block) {
2015 sgen_find_optimized_pin_queue_area (MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SKIP, MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE,
2016 &block->pin_queue_first_entry, &block->pin_queue_last_entry);
2017 } END_FOREACH_BLOCK;
2021 major_pin_objects (SgenGrayQueue *queue)
2025 FOREACH_BLOCK (block) {
2026 mark_pinned_objects_in_block (block, queue);
2027 } END_FOREACH_BLOCK;
2031 major_init_to_space (void)
2036 major_report_pinned_memory_usage (void)
2038 g_assert_not_reached ();
2042 major_get_used_size (void)
2047 FOREACH_BLOCK (block) {
2048 int count = MS_BLOCK_FREE / block->obj_size;
2050 size += count * block->obj_size;
2051 for (iter = block->free_list; iter; iter = (void**)*iter)
2052 size -= block->obj_size;
2053 } END_FOREACH_BLOCK;
2059 get_num_major_sections (void)
2061 return num_major_sections;
2065 major_handle_gc_param (const char *opt)
2067 if (g_str_has_prefix (opt, "evacuation-threshold=")) {
2068 const char *arg = strchr (opt, '=') + 1;
2069 int percentage = atoi (arg);
2070 if (percentage < 0 || percentage > 100) {
2071 fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
2074 evacuation_threshold = (float)percentage / 100.0f;
2076 } else if (!strcmp (opt, "lazy-sweep")) {
2079 } else if (!strcmp (opt, "no-lazy-sweep")) {
2088 major_print_gc_param_usage (void)
2092 " evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
2093 " (no-)lazy-sweep\n"
2098 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
2101 gboolean has_references;
2103 FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
2105 callback ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE);
2106 } END_FOREACH_BLOCK;
2109 #ifdef HEAVY_STATISTICS
2110 extern long long marked_cards;
2111 extern long long scanned_cards;
2112 extern long long scanned_objects;
2113 extern long long remarked_cards;
2116 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
2118 * MS blocks are 16K aligned.
2119 * Cardtables are 4K aligned, at least.
2120 * This means that the cardtable of a given block is 32 bytes aligned.
2123 initial_skip_card (guint8 *card_data)
2125 mword *cards = (mword*)card_data;
2128 for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
2134 if (i == CARD_WORDS_PER_BLOCK)
2135 return card_data + CARDS_PER_BLOCK;
2137 #if defined(__i386__) && defined(__GNUC__)
2138 return card_data + i * 4 + (__builtin_ffs (card) - 1) / 8;
2139 #elif defined(__x86_64__) && defined(__GNUC__)
2140 return card_data + i * 8 + (__builtin_ffsll (card) - 1) / 8;
2141 #elif defined(__s390x__) && defined(__GNUC__)
2142 return card_data + i * 8 + (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
2144 for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
2146 return &card_data [i];
2153 static G_GNUC_UNUSED guint8*
2154 skip_card (guint8 *card_data, guint8 *card_data_end)
2156 while (card_data < card_data_end && !*card_data)
2161 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
2162 #define MS_BLOCK_OBJ_FAST(b,os,i) ((b) + MS_BLOCK_SKIP + (os) * (i))
2163 #define MS_OBJ_ALLOCED_FAST(o,b) (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
2166 major_scan_card_table (gboolean mod_union, SgenGrayQueue *queue)
2169 gboolean has_references;
2170 ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
2172 #ifdef SGEN_HAVE_CONCURRENT_MARK
2173 if (!concurrent_mark)
2174 g_assert (!mod_union);
2176 g_assert (!mod_union);
2179 FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
2183 if (!has_references)
2186 block_obj_size = block->obj_size;
2187 block_start = MS_BLOCK_FOR_BLOCK_INFO (block);
2189 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
2191 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
2192 guint8 cards_data [CARDS_PER_BLOCK];
2194 char *obj, *end, *base;
2197 #ifdef SGEN_HAVE_CONCURRENT_MARK
2198 cards = block->cardtable_mod_union;
2200 * This happens when the nursery
2201 * collection that precedes finishing
2202 * the concurrent collection allocates
2209 /*We can avoid the extra copy since the remark cardtable was cleaned before */
2210 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
2211 cards = sgen_card_table_get_card_scan_address ((mword)block_start);
2214 if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
2219 obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
2220 end = block_start + MS_BLOCK_SIZE;
2221 base = sgen_card_table_align_pointer (obj);
2227 sweep_block (block, FALSE);
2229 if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
2233 /* FIXME: do this more efficiently */
2235 MS_CALC_MARK_BIT (w, b, obj);
2236 if (!MS_MARK_BIT (block, w, b))
2240 card_offset = (obj - base) >> CARD_BITS;
2241 sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, mod_union, queue);
2244 obj += block_obj_size;
2247 guint8 *card_data, *card_base;
2248 guint8 *card_data_end;
2251 * This is safe in face of card aliasing for the following reason:
2253 * Major blocks are 16k aligned, or 32 cards aligned.
2254 * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
2255 * sizes, they won't overflow the cardtable overlap modulus.
2258 #ifdef SGEN_HAVE_CONCURRENT_MARK
2259 card_data = card_base = block->cardtable_mod_union;
2261 * This happens when the nursery
2262 * collection that precedes finishing
2263 * the concurrent collection allocates
2269 g_assert_not_reached ();
2273 card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
2275 card_data_end = card_data + CARDS_PER_BLOCK;
2277 for (card_data = initial_skip_card (card_data); card_data < card_data_end; ++card_data) { //card_data = skip_card (card_data + 1, card_data_end)) {
2279 size_t idx = card_data - card_base;
2280 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
2281 char *end = start + CARD_SIZE_IN_BYTES;
2282 char *first_obj, *obj;
2284 HEAVY_STAT (++scanned_cards);
2290 sweep_block (block, FALSE);
2292 HEAVY_STAT (++marked_cards);
2294 sgen_card_table_prepare_card_for_scanning (card_data);
2299 index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
2301 obj = first_obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
2303 if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
2307 /* FIXME: do this more efficiently */
2309 MS_CALC_MARK_BIT (w, b, obj);
2310 if (!MS_MARK_BIT (block, w, b))
2314 HEAVY_STAT (++scanned_objects);
2315 scan_func (obj, sgen_obj_get_descriptor (obj), queue);
2317 obj += block_obj_size;
2319 HEAVY_STAT (if (*card_data) ++remarked_cards);
2320 binary_protocol_card_scan (first_obj, obj - first_obj);
2323 } END_FOREACH_BLOCK;
2327 major_count_cards (long long *num_total_cards, long long *num_marked_cards)
2330 gboolean has_references;
2331 long long total_cards = 0;
2332 long long marked_cards = 0;
2334 FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
2335 guint8 *cards = sgen_card_table_get_card_scan_address ((mword) MS_BLOCK_FOR_BLOCK_INFO (block));
2338 if (!has_references)
2341 total_cards += CARDS_PER_BLOCK;
2342 for (i = 0; i < CARDS_PER_BLOCK; ++i) {
2346 } END_FOREACH_BLOCK;
2348 *num_total_cards = total_cards;
2349 *num_marked_cards = marked_cards;
2352 #ifdef SGEN_HAVE_CONCURRENT_MARK
2354 update_cardtable_mod_union (void)
2358 FOREACH_BLOCK (block) {
2361 block->cardtable_mod_union = sgen_card_table_update_mod_union (block->cardtable_mod_union,
2362 MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE, &num_cards);
2364 SGEN_ASSERT (0, num_cards == CARDS_PER_BLOCK, "Number of cards calculation is wrong");
2365 } END_FOREACH_BLOCK;
2369 major_get_cardtable_mod_union_for_object (char *obj)
2371 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
2372 return &block->cardtable_mod_union [(obj - (char*)sgen_card_table_align_pointer (MS_BLOCK_FOR_BLOCK_INFO (block))) >> CARD_BITS];
2377 alloc_free_block_lists (MSBlockInfo ***lists)
2380 for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
2381 lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2384 #undef pthread_create
2387 post_param_init (SgenMajorCollector *collector)
2389 collector->sweeps_lazily = lazy_sweep;
2392 #ifdef SGEN_HAVE_CONCURRENT_MARK
2394 sgen_marksweep_init_internal (SgenMajorCollector *collector, gboolean is_concurrent)
2395 #else // SGEN_HAVE_CONCURRENT_MARK
2396 #error unknown configuration
2397 #endif // SGEN_HAVE_CONCURRENT_MARK
2401 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
2403 num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
2404 block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2405 ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
2407 evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2408 for (i = 0; i < num_block_obj_sizes; ++i)
2409 evacuate_block_obj_sizes [i] = FALSE;
2414 g_print ("block object sizes:\n");
2415 for (i = 0; i < num_block_obj_sizes; ++i)
2416 g_print ("%d\n", block_obj_sizes [i]);
2420 alloc_free_block_lists (free_block_lists);
2422 for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
2423 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
2424 for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
2425 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
2427 mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
2428 mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
2429 mono_counters_register ("# major blocks lazy swept", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_lazy_swept);
2430 mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
2431 #if SIZEOF_VOID_P != 8
2432 mono_counters_register ("# major blocks freed ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_ideal);
2433 mono_counters_register ("# major blocks freed less ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_less_ideal);
2434 mono_counters_register ("# major blocks freed individually", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_individual);
2435 mono_counters_register ("# major blocks allocated less ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced_less_ideal);
2438 collector->section_size = MAJOR_SECTION_SIZE;
2440 #ifdef SGEN_HAVE_CONCURRENT_MARK
2441 concurrent_mark = is_concurrent;
2442 if (is_concurrent) {
2443 collector->is_concurrent = TRUE;
2444 collector->want_synchronous_collection = &want_evacuation;
2448 collector->is_concurrent = FALSE;
2449 collector->want_synchronous_collection = NULL;
2451 collector->get_and_reset_num_major_objects_marked = major_get_and_reset_num_major_objects_marked;
2452 collector->supports_cardtable = TRUE;
2454 collector->have_swept = &have_swept;
2456 collector->alloc_heap = major_alloc_heap;
2457 collector->is_object_live = major_is_object_live;
2458 collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2459 collector->alloc_degraded = major_alloc_degraded;
2461 collector->alloc_object = major_alloc_object;
2462 collector->free_pinned_object = free_pinned_object;
2463 collector->iterate_objects = major_iterate_objects;
2464 collector->free_non_pinned_object = major_free_non_pinned_object;
2465 collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2466 collector->pin_objects = major_pin_objects;
2467 collector->pin_major_object = pin_major_object;
2468 collector->scan_card_table = major_scan_card_table;
2469 collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2470 #ifdef SGEN_HAVE_CONCURRENT_MARK
2471 if (is_concurrent) {
2472 collector->update_cardtable_mod_union = update_cardtable_mod_union;
2473 collector->get_cardtable_mod_union_for_object = major_get_cardtable_mod_union_for_object;
2476 collector->init_to_space = major_init_to_space;
2477 collector->sweep = major_sweep;
2478 collector->check_scan_starts = major_check_scan_starts;
2479 collector->dump_heap = major_dump_heap;
2480 collector->get_used_size = major_get_used_size;
2481 collector->start_nursery_collection = major_start_nursery_collection;
2482 collector->finish_nursery_collection = major_finish_nursery_collection;
2483 collector->start_major_collection = major_start_major_collection;
2484 collector->finish_major_collection = major_finish_major_collection;
2485 collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2486 collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2487 collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2488 collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2489 collector->get_num_major_sections = get_num_major_sections;
2490 collector->handle_gc_param = major_handle_gc_param;
2491 collector->print_gc_param_usage = major_print_gc_param_usage;
2492 collector->post_param_init = post_param_init;
2493 collector->is_valid_object = major_is_valid_object;
2494 collector->describe_pointer = major_describe_pointer;
2495 collector->count_cards = major_count_cards;
2497 collector->major_ops.copy_or_mark_object = major_copy_or_mark_object_canonical;
2498 collector->major_ops.scan_object = major_scan_object;
2499 #ifdef SGEN_HAVE_CONCURRENT_MARK
2500 if (is_concurrent) {
2501 collector->major_concurrent_ops.copy_or_mark_object = major_copy_or_mark_object_concurrent_canonical;
2502 collector->major_concurrent_ops.scan_object = major_scan_object_concurrent;
2503 collector->major_concurrent_ops.scan_vtype = major_scan_vtype_concurrent;
2507 #if !defined (FIXED_HEAP) && !defined (SGEN_PARALLEL_MARK)
2508 /* FIXME: this will not work with evacuation or the split nursery. */
2510 collector->drain_gray_stack = drain_gray_stack;
2512 #ifdef HEAVY_STATISTICS
2513 mono_counters_register ("Optimized copy", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy);
2514 mono_counters_register ("Optimized copy nursery", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_nursery);
2515 mono_counters_register ("Optimized copy nursery forwarded", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_nursery_forwarded);
2516 mono_counters_register ("Optimized copy nursery pinned", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_nursery_pinned);
2517 #ifdef SGEN_MARK_ON_ENQUEUE
2518 mono_counters_register ("Optimized copy major", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major);
2519 mono_counters_register ("Optimized copy major small fast", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major_small_fast);
2520 mono_counters_register ("Optimized copy major small slow", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major_small_slow);
2521 mono_counters_register ("Optimized copy major large", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major_large);
2523 mono_counters_register ("Optimized major mark", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_mark);
2524 mono_counters_register ("Optimized major mark small", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_mark_small);
2525 mono_counters_register ("Optimized major mark large", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_mark_large);
2526 mono_counters_register ("Optimized major scan", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan);
2527 mono_counters_register ("Optimized major scan no refs", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan_no_refs);
2528 #ifdef DESCRIPTOR_FAST_PATH
2529 mono_counters_register ("Optimized major scan slow", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan_slow);
2530 mono_counters_register ("Optimized major scan fast", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan_fast);
2533 mono_counters_register ("Gray stack drain loops", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_drain_loops);
2534 mono_counters_register ("Gray stack prefetch fills", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_drain_prefetch_fills);
2535 mono_counters_register ("Gray stack prefetch failures", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_drain_prefetch_fill_failures);
2539 #ifdef HEAVY_STATISTICS
2540 mono_mutex_init (&scanned_objects_list_lock);
2543 SGEN_ASSERT (0, SGEN_MAX_SMALL_OBJ_SIZE <= MS_BLOCK_FREE / 2, "MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2");
2545 /*cardtable requires major pages to be 8 cards aligned*/
2546 g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);
2549 #ifdef SGEN_HAVE_CONCURRENT_MARK
2551 sgen_marksweep_init (SgenMajorCollector *collector)
2553 sgen_marksweep_init_internal (collector, FALSE);
2557 sgen_marksweep_conc_init (SgenMajorCollector *collector)
2559 sgen_marksweep_init_internal (collector, TRUE);