2 * sgen-marksweep.c: Simple generational GC.
5 * Mark Probst <mark.probst@gmail.com>
7 * Copyright 2009-2010 Novell, Inc.
9 * Permission is hereby granted, free of charge, to any person obtaining
10 * a copy of this software and associated documentation files (the
11 * "Software"), to deal in the Software without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
24 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
25 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
26 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
36 #include "utils/mono-counters.h"
37 #include "utils/mono-semaphore.h"
38 #include "utils/mono-time.h"
39 #include "metadata/object-internals.h"
40 #include "metadata/profiler-private.h"
42 #include "metadata/sgen-gc.h"
43 #include "metadata/sgen-protocol.h"
44 #include "metadata/sgen-cardtable.h"
45 #include "metadata/gc-internal.h"
47 #define MS_BLOCK_SIZE (16*1024)
48 #define MS_BLOCK_SIZE_SHIFT 14
49 #define MAJOR_SECTION_SIZE MS_BLOCK_SIZE
50 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
53 #define MS_DEFAULT_HEAP_NUM_BLOCKS (32 * 1024) /* 512 MB */
57 * Don't allocate single blocks, but alloc a contingent of this many
58 * blocks in one swoop.
60 #define MS_BLOCK_ALLOC_NUM 32
63 * Number of bytes before the first object in a block. At the start
64 * of a block is the MSBlockHeader, then opional padding, then come
65 * the objects, so this must be >= sizeof (MSBlockHeader).
68 #define MS_BLOCK_SKIP 0
70 #define MS_BLOCK_SKIP 16
73 #define MS_BLOCK_FREE (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
75 #define MS_NUM_MARK_WORDS ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
77 #if SGEN_MAX_SMALL_OBJ_SIZE > MS_BLOCK_FREE / 2
78 #error MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2
81 typedef struct _MSBlockInfo MSBlockInfo;
85 int pin_queue_num_entries;
86 unsigned int pinned : 1;
87 unsigned int has_references : 1;
88 unsigned int has_pinned : 1; /* means cannot evacuate */
89 unsigned int is_to_space : 1;
91 unsigned int used : 1;
92 unsigned int zeroed : 1;
97 MSBlockInfo *next_free;
98 void **pin_queue_start;
99 mword mark_words [MS_NUM_MARK_WORDS];
103 static int ms_heap_num_blocks = MS_DEFAULT_HEAP_NUM_BLOCKS;
105 #define ms_heap_start nursery_end
106 static char *ms_heap_end;
108 #define MS_PTR_IN_SMALL_MAJOR_HEAP(p) ((char*)(p) >= ms_heap_start && (char*)(p) < ms_heap_end)
110 /* array of all all block infos in the system */
111 static MSBlockInfo *block_infos;
114 #define MS_BLOCK_OBJ(b,i) ((b)->block + MS_BLOCK_SKIP + (b)->obj_size * (i))
115 #define MS_BLOCK_DATA_FOR_OBJ(o) ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
118 #define MS_BLOCK_FOR_OBJ(o) (&block_infos [(mword)((char*)(o) - ms_heap_start) >> MS_BLOCK_SIZE_SHIFT])
124 #define MS_BLOCK_FOR_OBJ(o) (((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
127 #define MS_BLOCK_OBJ_INDEX(o,b) (((char*)(o) - ((b)->block + MS_BLOCK_SKIP)) / (b)->obj_size)
129 #define MS_CALC_MARK_BIT(w,b,o) do { \
130 int i = ((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o))) >> SGEN_ALLOC_ALIGN_BITS; \
131 if (sizeof (mword) == 4) { \
140 #define MS_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] & (1L << (b)))
141 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (1L << (b)))
142 #define MS_PAR_SET_MARK_BIT(was_marked,bl,w,b) do { \
143 mword __old = (bl)->mark_words [(w)]; \
144 mword __bitmask = 1L << (b); \
145 if (__old & __bitmask) { \
149 if (SGEN_CAS_PTR ((gpointer*)&(bl)->mark_words [(w)], \
150 (gpointer)(__old | __bitmask), \
151 (gpointer)__old) == \
153 was_marked = FALSE; \
158 #define MS_OBJ_ALLOCED(o,b) (*(void**)(o) && (*(char**)(o) < (b)->block || *(char**)(o) >= (b)->block + MS_BLOCK_SIZE))
160 #define MS_BLOCK_OBJ_SIZE_FACTOR (sqrt (2.0))
163 * This way we can lookup block object size indexes for sizes up to
164 * 256 bytes with a single load.
166 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES 32
168 static int *block_obj_sizes;
169 static int num_block_obj_sizes;
170 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
172 #define MS_BLOCK_FLAG_PINNED 1
173 #define MS_BLOCK_FLAG_REFS 2
175 #define MS_BLOCK_TYPE_MAX 4
177 #ifdef SGEN_PARALLEL_MARK
178 static LOCK_DECLARE (ms_block_list_mutex);
179 #define LOCK_MS_BLOCK_LIST pthread_mutex_lock (&ms_block_list_mutex)
180 #define UNLOCK_MS_BLOCK_LIST pthread_mutex_unlock (&ms_block_list_mutex)
183 /* we get this at init */
184 static int nursery_bits;
185 static char *nursery_start;
186 static char *nursery_end;
188 static gboolean *evacuate_block_obj_sizes;
189 static float evacuation_threshold = 0.666;
191 static gboolean concurrent_sweep = FALSE;
192 static gboolean have_swept;
194 #define ptr_in_nursery(p) (SGEN_PTR_IN_NURSERY ((p), nursery_bits, nursery_start, nursery_end))
196 /* all allocated blocks in the system */
197 static MSBlockInfo *all_blocks;
200 /* non-allocated block free-list */
201 static MSBlockInfo *empty_blocks = NULL;
203 /* non-allocated block free-list */
204 static void *empty_blocks = NULL;
205 static int num_empty_blocks = 0;
208 #define FOREACH_BLOCK(bl) for ((bl) = all_blocks; (bl); (bl) = (bl)->next) {
209 #define END_FOREACH_BLOCK }
211 static int num_major_sections = 0;
212 /* one free block list for each block object size */
213 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
215 #ifdef SGEN_PARALLEL_MARK
216 #ifdef HAVE_KW_THREAD
217 static __thread MSBlockInfo ***workers_free_block_lists;
219 static pthread_key_t workers_free_block_lists_key;
223 static long long stat_major_blocks_alloced = 0;
224 static long long stat_major_blocks_freed = 0;
225 static long long stat_major_objects_evacuated = 0;
226 static long long stat_time_wait_for_sweep = 0;
227 #ifdef SGEN_PARALLEL_MARK
228 static long long stat_slots_allocated_in_vain = 0;
231 static gboolean ms_sweep_in_progress = FALSE;
232 static pthread_t ms_sweep_thread;
233 static MonoSemType ms_sweep_cmd_semaphore;
234 static MonoSemType ms_sweep_done_semaphore;
237 ms_signal_sweep_command (void)
239 if (!concurrent_sweep)
242 g_assert (!ms_sweep_in_progress);
243 ms_sweep_in_progress = TRUE;
244 MONO_SEM_POST (&ms_sweep_cmd_semaphore);
248 ms_signal_sweep_done (void)
250 if (!concurrent_sweep)
253 MONO_SEM_POST (&ms_sweep_done_semaphore);
257 ms_wait_for_sweep_done (void)
259 SGEN_TV_DECLARE (atv);
260 SGEN_TV_DECLARE (btv);
263 if (!concurrent_sweep)
266 if (!ms_sweep_in_progress)
269 SGEN_TV_GETTIME (atv);
270 while ((result = MONO_SEM_WAIT (&ms_sweep_done_semaphore)) != 0) {
272 g_error ("MONO_SEM_WAIT");
274 SGEN_TV_GETTIME (btv);
275 stat_time_wait_for_sweep += SGEN_TV_ELAPSED_MS (atv, btv);
277 g_assert (ms_sweep_in_progress);
278 ms_sweep_in_progress = FALSE;
282 ms_find_block_obj_size_index (int size)
285 DEBUG (9, g_assert (size <= SGEN_MAX_SMALL_OBJ_SIZE));
286 for (i = 0; i < num_block_obj_sizes; ++i)
287 if (block_obj_sizes [i] >= size)
289 g_assert_not_reached ();
292 #define FREE_BLOCKS_FROM(lists,p,r) (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
293 #define FREE_BLOCKS(p,r) (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
294 #ifdef SGEN_PARALLEL_MARK
295 #ifdef HAVE_KW_THREAD
296 #define FREE_BLOCKS_LOCAL(p,r) (FREE_BLOCKS_FROM (workers_free_block_lists, (p), (r)))
298 #define FREE_BLOCKS_LOCAL(p,r) (FREE_BLOCKS_FROM (((MSBlockInfo***)(pthread_getspecific (workers_free_block_lists_key))), (p), (r)))
301 //#define FREE_BLOCKS_LOCAL(p,r) (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
304 #define MS_BLOCK_OBJ_SIZE_INDEX(s) \
305 (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ? \
306 fast_block_obj_size_indexes [((s)+7)>>3] : \
307 ms_find_block_obj_size_index ((s)))
311 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
314 mword major_heap_size = ms_heap_num_blocks * MS_BLOCK_SIZE;
315 mword alloc_size = nursery_size + major_heap_size;
318 g_assert (ms_heap_num_blocks > 0);
319 g_assert (nursery_size % MS_BLOCK_SIZE == 0);
321 g_assert (nursery_align % MS_BLOCK_SIZE == 0);
323 nursery_start = mono_sgen_alloc_os_memory_aligned (alloc_size, nursery_align ? nursery_align : MS_BLOCK_SIZE, TRUE);
324 nursery_end = heap_start = nursery_start + nursery_size;
325 nursery_bits = the_nursery_bits;
327 ms_heap_end = heap_start + major_heap_size;
329 block_infos = mono_sgen_alloc_internal_dynamic (sizeof (MSBlockInfo) * ms_heap_num_blocks, INTERNAL_MEM_MS_BLOCK_INFO);
331 for (i = 0; i < ms_heap_num_blocks; ++i) {
332 block_infos [i].block = heap_start + i * MS_BLOCK_SIZE;
333 if (i < ms_heap_num_blocks - 1)
334 block_infos [i].next_free = &block_infos [i + 1];
336 block_infos [i].next_free = NULL;
337 block_infos [i].zeroed = TRUE;
340 empty_blocks = &block_infos [0];
342 return nursery_start;
346 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
349 nursery_start = mono_sgen_alloc_os_memory_aligned (nursery_size, nursery_align, TRUE);
351 nursery_start = mono_sgen_alloc_os_memory (nursery_size, TRUE);
353 nursery_end = nursery_start + nursery_size;
354 nursery_bits = the_nursery_bits;
356 return nursery_start;
361 update_heap_boundaries_for_block (MSBlockInfo *block)
363 mono_sgen_update_heap_boundaries ((mword)block->block, (mword)block->block + MS_BLOCK_SIZE);
368 ms_get_empty_block (void)
372 g_assert (empty_blocks);
375 block = empty_blocks;
376 } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block->next_free, block) != block);
381 memset (block->block, 0, MS_BLOCK_SIZE);
387 ms_free_block (MSBlockInfo *block)
389 block->next_free = empty_blocks;
390 empty_blocks = block;
392 block->zeroed = FALSE;
393 mono_sgen_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
397 ms_get_empty_block (void)
401 void *block, *empty, *next;
405 p = mono_sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * MS_BLOCK_ALLOC_NUM, MS_BLOCK_SIZE, TRUE);
407 for (i = 0; i < MS_BLOCK_ALLOC_NUM; ++i) {
410 * We do the free list update one after the
411 * other so that other threads can use the new
412 * blocks as quickly as possible.
415 empty = empty_blocks;
416 *(void**)block = empty;
417 } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
421 SGEN_ATOMIC_ADD (num_empty_blocks, MS_BLOCK_ALLOC_NUM);
423 stat_major_blocks_alloced += MS_BLOCK_ALLOC_NUM;
427 empty = empty_blocks;
431 next = *(void**)block;
432 } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
434 SGEN_ATOMIC_ADD (num_empty_blocks, -1);
436 *(void**)block = NULL;
438 g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
444 ms_free_block (void *block)
448 mono_sgen_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
449 memset (block, 0, MS_BLOCK_SIZE);
452 empty = empty_blocks;
453 *(void**)block = empty;
454 } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
456 SGEN_ATOMIC_ADD (num_empty_blocks, 1);
460 //#define MARKSWEEP_CONSISTENCY_CHECK
462 #ifdef MARKSWEEP_CONSISTENCY_CHECK
464 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
468 for (; block; block = block->next_free) {
469 g_assert (block->obj_size == size);
470 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
472 /* blocks in the free lists must have at least
474 g_assert (block->free_list);
477 /* the block must not be in the empty_blocks list */
478 for (b = empty_blocks; b; b = b->next_free)
479 g_assert (b != block);
481 /* the block must be in the all_blocks list */
482 for (b = all_blocks; b; b = b->next) {
486 g_assert (b == block);
491 check_empty_blocks (void)
496 for (p = empty_blocks; p; p = *(void**)p)
498 g_assert (i == num_empty_blocks);
503 consistency_check (void)
508 /* check all blocks */
509 FOREACH_BLOCK (block) {
510 int count = MS_BLOCK_FREE / block->obj_size;
515 /* check block header */
516 g_assert (((MSBlockHeader*)block->block)->info == block);
519 /* count number of free slots */
520 for (i = 0; i < count; ++i) {
521 void **obj = (void**) MS_BLOCK_OBJ (block, i);
522 if (!MS_OBJ_ALLOCED (obj, block))
526 /* check free list */
527 for (free = block->free_list; free; free = (void**)*free) {
528 g_assert (MS_BLOCK_FOR_OBJ (free) == block);
531 g_assert (num_free == 0);
533 /* check all mark words are zero */
534 for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
535 g_assert (block->mark_words [i] == 0);
538 /* check free blocks */
539 for (i = 0; i < num_block_obj_sizes; ++i) {
541 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
542 check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
545 check_empty_blocks ();
550 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
552 int size = block_obj_sizes [size_index];
553 int count = MS_BLOCK_FREE / size;
555 #ifdef SGEN_PARALLEL_MARK
559 MSBlockHeader *header;
561 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
565 if (!mono_sgen_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
569 info = ms_get_empty_block ();
571 info = mono_sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
574 DEBUG (9, g_assert (count >= 2));
576 info->obj_size = size;
577 info->obj_size_index = size_index;
578 info->pinned = pinned;
579 info->has_references = has_references;
580 info->has_pinned = pinned;
581 info->is_to_space = (mono_sgen_get_current_collection_generation () == GENERATION_OLD);
583 info->block = ms_get_empty_block ();
585 header = (MSBlockHeader*) info->block;
589 update_heap_boundaries_for_block (info);
591 /* build free list */
592 obj_start = info->block + MS_BLOCK_SKIP;
593 info->free_list = (void**)obj_start;
594 /* we're skipping the last one - it must be nulled */
595 for (i = 0; i < count - 1; ++i) {
596 char *next_obj_start = obj_start + size;
597 *(void**)obj_start = next_obj_start;
598 obj_start = next_obj_start;
601 *(void**)obj_start = NULL;
603 #ifdef SGEN_PARALLEL_MARK
605 next = info->next_free = free_blocks [size_index];
606 } while (SGEN_CAS_PTR ((void**)&free_blocks [size_index], info, next) != next);
609 next = info->next = all_blocks;
610 } while (SGEN_CAS_PTR ((void**)&all_blocks, info, next) != next);
612 info->next_free = free_blocks [size_index];
613 free_blocks [size_index] = info;
615 info->next = all_blocks;
619 ++num_major_sections;
624 obj_is_from_pinned_alloc (char *ptr)
628 FOREACH_BLOCK (block) {
629 if (ptr >= block->block && ptr <= block->block + MS_BLOCK_SIZE)
630 return block->pinned;
636 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
641 block = free_blocks [size_index];
642 DEBUG (9, g_assert (block));
644 obj = block->free_list;
645 DEBUG (9, g_assert (obj));
647 block->free_list = *(void**)obj;
648 if (!block->free_list) {
649 free_blocks [size_index] = block->next_free;
650 block->next_free = NULL;
656 #ifdef SGEN_PARALLEL_MARK
658 try_remove_block_from_free_list (MSBlockInfo *block, MSBlockInfo **free_blocks, int size_index)
661 * No more free slots in the block, so try to free the block.
662 * Don't try again if we don't succeed - another thread will
663 * already have done it.
665 MSBlockInfo *next_block = block->next_free;
666 if (SGEN_CAS_PTR ((void**)&free_blocks [size_index], next_block, block) == block) {
668 void *old = SGEN_CAS_PTR ((void**)&block->next_free, NULL, next_block);
669 g_assert (old == next_block);
671 block->next_free = NULL;
678 alloc_obj_par (int size, gboolean pinned, gboolean has_references)
680 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
681 MSBlockInfo **free_blocks_local = FREE_BLOCKS_LOCAL (pinned, has_references);
685 DEBUG (9, g_assert (!ms_sweep_in_progress));
686 DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
688 if (free_blocks_local [size_index]) {
690 obj = unlink_slot_from_free_list_uncontested (free_blocks_local, size_index);
692 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
695 block = free_blocks [size_index];
697 if (!try_remove_block_from_free_list (block, free_blocks, size_index))
700 g_assert (block->next_free == NULL);
701 g_assert (block->free_list);
702 block->next_free = free_blocks_local [size_index];
703 free_blocks_local [size_index] = block;
710 success = ms_alloc_block (size_index, pinned, has_references);
711 UNLOCK_MS_BLOCK_LIST;
713 if (G_UNLIKELY (!success))
721 * FIXME: This should not be necessary because it'll be
722 * overwritten by the vtable immediately.
731 alloc_obj (int size, gboolean pinned, gboolean has_references)
733 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
734 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
737 #ifdef SGEN_PARALLEL_MARK
738 DEBUG (9, g_assert (current_collection_generation != GENERATION_OLD));
741 DEBUG (9, g_assert (!ms_sweep_in_progress));
743 if (!free_blocks [size_index]) {
744 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
748 obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
751 * FIXME: This should not be necessary because it'll be
752 * overwritten by the vtable immediately.
760 major_alloc_object (int size, gboolean has_references)
762 return alloc_obj (size, FALSE, has_references);
766 * We're not freeing the block if it's empty. We leave that work for
767 * the next major collection.
769 * This is just called from the domain clearing code, which runs in a
770 * single thread and has the GC lock, so we don't need an extra lock.
773 free_object (char *obj, size_t size, gboolean pinned)
775 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
777 DEBUG (9, g_assert ((pinned && block->pinned) || (!pinned && !block->pinned)));
778 DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
779 MS_CALC_MARK_BIT (word, bit, obj);
780 DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
781 if (!block->free_list) {
782 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
783 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
784 DEBUG (9, g_assert (!block->next_free));
785 block->next_free = free_blocks [size_index];
786 free_blocks [size_index] = block;
788 memset (obj, 0, size);
789 *(void**)obj = block->free_list;
790 block->free_list = (void**)obj;
794 major_free_non_pinned_object (char *obj, size_t size)
796 free_object (obj, size, FALSE);
799 /* size is a multiple of SGEN_ALLOC_ALIGN */
801 major_alloc_small_pinned_obj (size_t size, gboolean has_references)
805 ms_wait_for_sweep_done ();
807 res = alloc_obj (size, TRUE, has_references);
808 /*If we failed to alloc memory, we better try releasing memory
809 *as pinned alloc is requested by the runtime.
812 sgen_collect_major_no_lock ("pinned alloc failure");
813 res = alloc_obj (size, TRUE, has_references);
819 free_pinned_object (char *obj, size_t size)
821 free_object (obj, size, TRUE);
825 * size is already rounded up and we hold the GC lock.
828 major_alloc_degraded (MonoVTable *vtable, size_t size)
831 int old_num_sections;
833 ms_wait_for_sweep_done ();
835 old_num_sections = num_major_sections;
837 obj = alloc_obj (size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
838 if (G_LIKELY (obj)) {
839 *(MonoVTable**)obj = vtable;
840 HEAVY_STAT (++stat_objects_alloced_degraded);
841 HEAVY_STAT (stat_bytes_alloced_degraded += size);
842 g_assert (num_major_sections >= old_num_sections);
843 mono_sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
848 #define MAJOR_OBJ_IS_IN_TO_SPACE(obj) FALSE
851 * obj is some object. If it's not in the major heap (i.e. if it's in
852 * the nursery or LOS), return FALSE. Otherwise return whether it's
853 * been marked or copied.
856 major_is_object_live (char *obj)
864 if (ptr_in_nursery (obj))
869 if (!MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
872 objsize = SGEN_ALIGN_UP (mono_sgen_safe_object_get_size ((MonoObject*)obj));
875 if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
879 /* now we know it's in a major block */
880 block = MS_BLOCK_FOR_OBJ (obj);
881 DEBUG (9, g_assert (!block->pinned));
882 MS_CALC_MARK_BIT (word, bit, obj);
883 return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
887 major_ptr_is_in_non_pinned_space (char *ptr)
891 FOREACH_BLOCK (block) {
892 if (ptr >= block->block && ptr <= block->block + MS_BLOCK_SIZE)
893 return !block->pinned;
899 major_iterate_objects (gboolean non_pinned, gboolean pinned, IterateObjectCallbackFunc callback, void *data)
903 ms_wait_for_sweep_done ();
905 FOREACH_BLOCK (block) {
906 int count = MS_BLOCK_FREE / block->obj_size;
909 if (block->pinned && !pinned)
911 if (!block->pinned && !non_pinned)
914 for (i = 0; i < count; ++i) {
915 void **obj = (void**) MS_BLOCK_OBJ (block, i);
916 if (MS_OBJ_ALLOCED (obj, block))
917 callback ((char*)obj, block->obj_size, data);
923 major_check_scan_starts (void)
928 major_dump_heap (FILE *heap_dump_file)
931 int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
932 int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
935 for (i = 0; i < num_block_obj_sizes; ++i)
936 slots_available [i] = slots_used [i] = 0;
938 FOREACH_BLOCK (block) {
939 int index = ms_find_block_obj_size_index (block->obj_size);
940 int count = MS_BLOCK_FREE / block->obj_size;
942 slots_available [index] += count;
943 for (i = 0; i < count; ++i) {
944 if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
945 ++slots_used [index];
949 fprintf (heap_dump_file, "<occupancies>\n");
950 for (i = 0; i < num_block_obj_sizes; ++i) {
951 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
952 block_obj_sizes [i], slots_available [i], slots_used [i]);
954 fprintf (heap_dump_file, "</occupancies>\n");
956 FOREACH_BLOCK (block) {
957 int count = MS_BLOCK_FREE / block->obj_size;
961 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
963 for (i = 0; i <= count; ++i) {
964 if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
969 mono_sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), block->block);
975 fprintf (heap_dump_file, "</section>\n");
979 #define LOAD_VTABLE SGEN_LOAD_VTABLE
981 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,block,queue) do { \
983 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
984 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
985 MS_SET_MARK_BIT ((block), __word, __bit); \
986 if ((block)->has_references) \
987 GRAY_OBJECT_ENQUEUE ((queue), (obj)); \
988 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), mono_sgen_safe_object_get_size ((MonoObject*)(obj))); \
991 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do { \
993 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
994 DEBUG (9, g_assert (MS_OBJ_ALLOCED ((obj), (block)))); \
995 if (!MS_MARK_BIT ((block), __word, __bit)) { \
996 MS_SET_MARK_BIT ((block), __word, __bit); \
997 if ((block)->has_references) \
998 GRAY_OBJECT_ENQUEUE ((queue), (obj)); \
999 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), mono_sgen_safe_object_get_size ((MonoObject*)(obj))); \
1002 #define MS_PAR_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do { \
1003 int __word, __bit; \
1004 gboolean __was_marked; \
1005 DEBUG (9, g_assert (MS_OBJ_ALLOCED ((obj), (block)))); \
1006 MS_CALC_MARK_BIT (__word, __bit, (obj)); \
1007 MS_PAR_SET_MARK_BIT (__was_marked, (block), __word, __bit); \
1008 if (!__was_marked) { \
1009 if ((block)->has_references) \
1010 GRAY_OBJECT_ENQUEUE ((queue), (obj)); \
1011 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), mono_sgen_safe_object_get_size ((MonoObject*)(obj))); \
1016 pin_major_object (void *obj, SgenGrayQueue *queue)
1018 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1019 block->has_pinned = TRUE;
1020 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1023 #ifdef SGEN_PARALLEL_MARK
1025 pin_or_update_par (void **ptr, void *obj, MonoVTable *vt, SgenGrayQueue *queue)
1030 if (ptr_in_nursery (obj)) {
1031 if (SGEN_CAS_PTR (obj, (void*)((mword)vt | SGEN_PINNED_BIT), vt) == vt) {
1032 mono_sgen_pin_object (obj, queue);
1036 pin_major_object (obj, queue);
1039 vtable_word = *(mword*)obj;
1040 /*someone else forwarded it, update the pointer and bail out*/
1041 if (vtable_word & SGEN_FORWARDED_BIT) {
1042 *ptr = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1046 /*someone pinned it, nothing to do.*/
1047 if (vtable_word & SGEN_PINNED_BIT)
1053 #include "sgen-major-copy-object.h"
1055 #ifdef SGEN_PARALLEL_MARK
1057 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1064 HEAVY_STAT (++stat_copy_object_called_major);
1066 DEBUG (9, g_assert (obj));
1067 DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
1069 if (ptr_in_nursery (obj)) {
1071 gboolean has_references;
1073 mword vtable_word = *(mword*)obj;
1074 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1076 if (vtable_word & SGEN_FORWARDED_BIT) {
1081 if (vtable_word & SGEN_PINNED_BIT)
1084 HEAVY_STAT (++stat_objects_copied_major);
1087 objsize = SGEN_ALIGN_UP (mono_sgen_par_object_get_size (vt, (MonoObject*)obj));
1088 has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
1090 destination = alloc_obj_par (objsize, FALSE, has_references);
1091 if (G_UNLIKELY (!destination)) {
1092 if (!ptr_in_nursery (obj)) {
1094 block = MS_BLOCK_FOR_OBJ (obj);
1095 size_index = block->obj_size_index;
1096 evacuate_block_obj_sizes [size_index] = FALSE;
1099 pin_or_update_par (ptr, obj, vt, queue);
1104 * We do this before the CAS because we want to make
1105 * sure that if another thread sees the destination
1106 * pointer the VTable is already in place. Not doing
1107 * this can crash binary protocols.
1109 *(MonoVTable**)destination = vt;
1111 if (SGEN_CAS_PTR (obj, (void*)((mword)destination | SGEN_FORWARDED_BIT), vt) == vt) {
1112 gboolean was_marked;
1114 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
1119 * FIXME: If we make major_alloc_object() give
1120 * us the block info, too, we won't have to
1123 block = MS_BLOCK_FOR_OBJ (obj);
1124 MS_CALC_MARK_BIT (word, bit, obj);
1125 DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
1126 MS_PAR_SET_MARK_BIT (was_marked, block, word, bit);
1129 * FIXME: We have allocated destination, but
1130 * we cannot use it. Give it back to the
1133 *(void**)destination = NULL;
1135 vtable_word = *(mword*)obj;
1136 g_assert (vtable_word & SGEN_FORWARDED_BIT);
1138 obj = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1142 ++stat_slots_allocated_in_vain;
1146 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1148 mword vtable_word = *(mword*)obj;
1149 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1151 /* see comment in the non-parallel version below */
1152 if (vtable_word & SGEN_FORWARDED_BIT) {
1156 objsize = SGEN_ALIGN_UP (mono_sgen_par_object_get_size (vt, (MonoObject*)obj));
1158 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1163 block = MS_BLOCK_FOR_OBJ (obj);
1164 size_index = block->obj_size_index;
1166 if (!block->has_pinned && evacuate_block_obj_sizes [size_index]) {
1167 if (block->is_to_space)
1172 mword vtable_word = *(mword*)obj;
1173 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1175 if (vtable_word & SGEN_FORWARDED_BIT) {
1182 HEAVY_STAT (++stat_major_objects_evacuated);
1183 goto do_copy_object;
1186 MS_PAR_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1189 mword vtable_word = *(mword*)obj;
1190 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1193 if (vtable_word & SGEN_PINNED_BIT)
1195 binary_protocol_pin (obj, vt, mono_sgen_safe_object_get_size ((MonoObject*)obj));
1196 if (SGEN_CAS_PTR (obj, (void*)(vtable_word | SGEN_PINNED_BIT), (void*)vtable_word) == (void*)vtable_word) {
1197 if (SGEN_VTABLE_HAS_REFERENCES (vt))
1198 GRAY_OBJECT_ENQUEUE (queue, obj);
1200 g_assert (SGEN_OBJECT_IS_PINNED (obj));
1207 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1212 HEAVY_STAT (++stat_copy_object_called_major);
1214 DEBUG (9, g_assert (obj));
1215 DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
1217 if (ptr_in_nursery (obj)) {
1219 char *forwarded, *old_obj;
1221 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1225 if (SGEN_OBJECT_IS_PINNED (obj))
1228 HEAVY_STAT (++stat_objects_copied_major);
1232 obj = copy_object_no_checks (obj, queue);
1233 if (G_UNLIKELY (old_obj == obj)) {
1234 /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
1235 if (!ptr_in_nursery (obj)) {
1237 block = MS_BLOCK_FOR_OBJ (obj);
1238 size_index = block->obj_size_index;
1239 evacuate_block_obj_sizes [size_index] = FALSE;
1240 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1247 * FIXME: See comment for copy_object_no_checks(). If
1248 * we have that, we can let the allocation function
1249 * give us the block info, too, and we won't have to
1252 block = MS_BLOCK_FOR_OBJ (obj);
1253 MS_CALC_MARK_BIT (word, bit, obj);
1254 DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
1255 MS_SET_MARK_BIT (block, word, bit);
1259 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1264 * If we have don't have a fixed heap we cannot know
1265 * whether an object is in the LOS or in the small
1266 * object major heap without checking its size. To do
1267 * that, however, we need to know that we actually
1268 * have a valid object, not a forwarding pointer, so
1269 * we have to do this check first.
1271 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1276 objsize = SGEN_ALIGN_UP (mono_sgen_safe_object_get_size ((MonoObject*)obj));
1278 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1284 block = MS_BLOCK_FOR_OBJ (obj);
1285 size_index = block->obj_size_index;
1286 evacuate = evacuate_block_obj_sizes [size_index];
1290 * We could also check for !block->has_pinned
1291 * here, but it would only make an uncommon case
1292 * faster, namely objects that are in blocks
1293 * whose slot sizes are evacuated but which have
1296 if (evacuate && (forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1302 if (evacuate && !block->has_pinned) {
1303 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1304 if (block->is_to_space)
1306 HEAVY_STAT (++stat_major_objects_evacuated);
1307 goto do_copy_object;
1309 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1312 if (SGEN_OBJECT_IS_PINNED (obj))
1314 binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), mono_sgen_safe_object_get_size ((MonoObject*)obj));
1315 SGEN_PIN_OBJECT (obj);
1316 /* FIXME: only enqueue if object has references */
1317 GRAY_OBJECT_ENQUEUE (queue, obj);
1323 #include "sgen-major-scan-object.h"
1326 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
1329 int last_index = -1;
1331 if (!block->pin_queue_num_entries)
1334 block->has_pinned = TRUE;
1336 for (i = 0; i < block->pin_queue_num_entries; ++i) {
1337 int index = MS_BLOCK_OBJ_INDEX (block->pin_queue_start [i], block);
1338 DEBUG (9, g_assert (index >= 0 && index < MS_BLOCK_FREE / block->obj_size));
1339 if (index == last_index)
1341 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (MS_BLOCK_OBJ (block, index), block, queue);
1352 /* statistics for evacuation */
1353 int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1354 int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1355 int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1357 for (i = 0; i < num_block_obj_sizes; ++i)
1358 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1360 /* clear all the free lists */
1361 for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1362 MSBlockInfo **free_blocks = free_block_lists [i];
1364 for (j = 0; j < num_block_obj_sizes; ++j)
1365 free_blocks [j] = NULL;
1368 /* traverse all blocks, free and zero unmarked objects */
1371 MSBlockInfo *block = *iter;
1373 gboolean have_live = FALSE;
1374 gboolean has_pinned;
1378 obj_size_index = block->obj_size_index;
1380 has_pinned = block->has_pinned;
1381 block->has_pinned = block->pinned;
1383 block->is_to_space = FALSE;
1385 count = MS_BLOCK_FREE / block->obj_size;
1386 block->free_list = NULL;
1388 for (obj_index = 0; obj_index < count; ++obj_index) {
1390 void *obj = MS_BLOCK_OBJ (block, obj_index);
1392 MS_CALC_MARK_BIT (word, bit, obj);
1393 if (MS_MARK_BIT (block, word, bit)) {
1394 DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
1397 ++slots_used [obj_size_index];
1399 /* an unmarked object */
1400 if (MS_OBJ_ALLOCED (obj, block)) {
1401 binary_protocol_empty (obj, block->obj_size);
1402 memset (obj, 0, block->obj_size);
1404 *(void**)obj = block->free_list;
1405 block->free_list = obj;
1409 /* reset mark bits */
1410 memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1413 * FIXME: reverse free list so that it's in address
1419 ++num_blocks [obj_size_index];
1420 slots_available [obj_size_index] += count;
1423 iter = &block->next;
1426 * If there are free slots in the block, add
1427 * the block to the corresponding free list.
1429 if (block->free_list) {
1430 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1431 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1432 block->next_free = free_blocks [index];
1433 free_blocks [index] = block;
1436 update_heap_boundaries_for_block (block);
1439 * Blocks without live objects are removed from the
1440 * block list and freed.
1442 *iter = block->next;
1445 ms_free_block (block);
1447 ms_free_block (block->block);
1449 mono_sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
1452 --num_major_sections;
1456 for (i = 0; i < num_block_obj_sizes; ++i) {
1457 float usage = (float)slots_used [i] / (float)slots_available [i];
1458 if (num_blocks [i] > 5 && usage < evacuation_threshold) {
1459 evacuate_block_obj_sizes [i] = TRUE;
1461 g_print ("slot size %d - %d of %d used\n",
1462 block_obj_sizes [i], slots_used [i], slots_available [i]);
1465 evacuate_block_obj_sizes [i] = FALSE;
1473 ms_sweep_thread_func (void *dummy)
1475 g_assert (concurrent_sweep);
1480 while ((result = MONO_SEM_WAIT (&ms_sweep_cmd_semaphore)) != 0) {
1482 g_error ("MONO_SEM_WAIT");
1487 ms_signal_sweep_done ();
1496 if (concurrent_sweep) {
1497 g_assert (ms_sweep_thread);
1498 ms_signal_sweep_command ();
1504 static int count_pinned_ref;
1505 static int count_pinned_nonref;
1506 static int count_nonpinned_ref;
1507 static int count_nonpinned_nonref;
1510 count_nonpinned_callback (char *obj, size_t size, void *data)
1512 MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1514 if (vtable->klass->has_references)
1515 ++count_nonpinned_ref;
1517 ++count_nonpinned_nonref;
1521 count_pinned_callback (char *obj, size_t size, void *data)
1523 MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1525 if (vtable->klass->has_references)
1528 ++count_pinned_nonref;
1531 static void __attribute__ ((unused))
1532 count_ref_nonref_objs (void)
1536 count_pinned_ref = 0;
1537 count_pinned_nonref = 0;
1538 count_nonpinned_ref = 0;
1539 count_nonpinned_nonref = 0;
1541 major_iterate_objects (TRUE, FALSE, count_nonpinned_callback, NULL);
1542 major_iterate_objects (FALSE, TRUE, count_pinned_callback, NULL);
1544 total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1546 g_print ("ref: %d pinned %d non-pinned non-ref: %d pinned %d non-pinned -- %.1f\n",
1547 count_pinned_ref, count_nonpinned_ref,
1548 count_pinned_nonref, count_nonpinned_nonref,
1549 (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1553 ms_calculate_block_obj_sizes (double factor, int *arr)
1555 double target_size = sizeof (MonoObject);
1560 int target_count = ceil (MS_BLOCK_FREE / target_size);
1561 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1563 if (size != last_size) {
1565 arr [num_sizes] = size;
1570 target_size *= factor;
1571 } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1576 /* only valid during minor collections */
1577 static int old_num_major_sections;
1580 major_start_nursery_collection (void)
1582 ms_wait_for_sweep_done ();
1584 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1585 consistency_check ();
1588 old_num_major_sections = num_major_sections;
1592 major_finish_nursery_collection (void)
1594 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1595 consistency_check ();
1597 mono_sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1601 major_start_major_collection (void)
1605 ms_wait_for_sweep_done ();
1607 /* clear the free lists */
1608 for (i = 0; i < num_block_obj_sizes; ++i) {
1609 if (!evacuate_block_obj_sizes [i])
1612 free_block_lists [0][i] = NULL;
1613 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1618 major_finish_major_collection (void)
1623 major_have_computer_minor_collection_allowance (void)
1626 int section_reserve = mono_sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1628 g_assert (have_swept);
1629 ms_wait_for_sweep_done ();
1630 g_assert (!ms_sweep_in_progress);
1633 * FIXME: We don't free blocks on 32 bit platforms because it
1634 * can lead to address space fragmentation, since we're
1635 * allocating blocks in larger contingents.
1637 if (sizeof (mword) < 8)
1640 while (num_empty_blocks > section_reserve) {
1641 void *next = *(void**)empty_blocks;
1642 mono_sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE);
1643 empty_blocks = next;
1645 * Needs not be atomic because this is running
1650 ++stat_major_blocks_freed;
1656 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
1660 FOREACH_BLOCK (block) {
1661 block->pin_queue_start = mono_sgen_find_optimized_pin_queue_area (block->block + MS_BLOCK_SKIP, block->block + MS_BLOCK_SIZE,
1662 &block->pin_queue_num_entries);
1663 } END_FOREACH_BLOCK;
1667 major_pin_objects (SgenGrayQueue *queue)
1671 FOREACH_BLOCK (block) {
1672 mark_pinned_objects_in_block (block, queue);
1673 } END_FOREACH_BLOCK;
1677 major_init_to_space (void)
1682 major_report_pinned_memory_usage (void)
1684 g_assert_not_reached ();
1688 major_get_used_size (void)
1693 FOREACH_BLOCK (block) {
1694 int count = MS_BLOCK_FREE / block->obj_size;
1696 size += count * block->obj_size;
1697 for (iter = block->free_list; iter; iter = (void**)*iter)
1698 size -= block->obj_size;
1699 } END_FOREACH_BLOCK;
1705 get_num_major_sections (void)
1707 return num_major_sections;
1711 major_handle_gc_param (const char *opt)
1714 if (g_str_has_prefix (opt, "major-heap-size=")) {
1715 const char *arg = strchr (opt, '=') + 1;
1717 if (!mono_gc_parse_environment_string_extract_number (arg, &size))
1719 ms_heap_num_blocks = (size + MS_BLOCK_SIZE - 1) / MS_BLOCK_SIZE;
1720 g_assert (ms_heap_num_blocks > 0);
1724 if (g_str_has_prefix (opt, "evacuation-threshold=")) {
1725 const char *arg = strchr (opt, '=') + 1;
1726 int percentage = atoi (arg);
1727 if (percentage < 0 || percentage > 100) {
1728 fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
1731 evacuation_threshold = (float)percentage / 100.0;
1733 } else if (!strcmp (opt, "concurrent-sweep")) {
1734 concurrent_sweep = TRUE;
1736 } else if (!strcmp (opt, "no-concurrent-sweep")) {
1737 concurrent_sweep = FALSE;
1745 major_print_gc_param_usage (void)
1750 " major-heap-size=N (where N is an integer, possibly with a k, m or a g suffix)\n"
1752 " evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
1753 " (no-)concurrent-sweep\n"
1757 #ifdef SGEN_HAVE_CARDTABLE
1759 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
1763 FOREACH_BLOCK (block) {
1764 if (block->has_references)
1765 callback ((mword)block->block, MS_BLOCK_SIZE);
1766 } END_FOREACH_BLOCK;
1769 #ifdef HEAVY_STATISTICS
1770 extern long long marked_cards;
1771 extern long long scanned_cards;
1772 extern long long scanned_objects;
1776 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
1778 * MS blocks are 16K aligned.
1779 * Cardtables are 4K aligned, at least.
1780 * This means that the cardtable of a given block is 32 bytes aligned.
1783 initial_skip_card (guint8 *card_data)
1785 mword *cards = (mword*)card_data;
1788 for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
1794 if (i == CARD_WORDS_PER_BLOCK)
1795 return card_data + CARDS_PER_BLOCK;
1797 #if defined(__i386__) && defined(__GNUC__)
1798 return card_data + i * 4 + (__builtin_ffs (card) - 1) / 8;
1799 #elif defined(__x86_64__) && defined(__GNUC__)
1800 return card_data + i * 8 + (__builtin_ffsll (card) - 1) / 8;
1801 #elif defined(__s390x__) && defined(__GNUC__)
1802 return card_data + i * 8 + (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1804 for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
1806 return &card_data [i];
1813 static G_GNUC_UNUSED guint8*
1814 skip_card (guint8 *card_data, guint8 *card_data_end)
1816 while (card_data < card_data_end && !*card_data)
1821 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
1822 #define MS_BLOCK_OBJ_FAST(b,os,i) ((b) + MS_BLOCK_SKIP + (os) * (i))
1823 #define MS_OBJ_ALLOCED_FAST(o,b) (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
1826 major_scan_card_table (SgenGrayQueue *queue)
1830 FOREACH_BLOCK (block) {
1834 if (!block->has_references)
1837 block_obj_size = block->obj_size;
1838 block_start = block->block;
1840 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
1842 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
1843 guint8 cards_data [CARDS_PER_BLOCK];
1845 char *obj, *end, *base;
1847 /*We can avoid the extra copy since the remark cardtable was cleaned before */
1848 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1849 cards = sgen_card_table_get_card_scan_address ((mword)block_start);
1852 if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
1856 obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
1857 end = block_start + MS_BLOCK_SIZE;
1858 base = sgen_card_table_align_pointer (obj);
1861 if (MS_OBJ_ALLOCED_FAST (obj, block_start)) {
1862 int card_offset = (obj - base) >> CARD_BITS;
1863 sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, queue);
1865 obj += block_obj_size;
1868 ScanObjectFunc scan_func = mono_sgen_get_minor_scan_object ();
1869 guint8 *card_data, *card_base;
1870 guint8 *card_data_end;
1873 * This is safe in face of card aliasing for the following reason:
1875 * Major blocks are 16k aligned, or 32 cards aligned.
1876 * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
1877 * sizes, they won't overflow the cardtable overlap modulus.
1879 card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
1880 card_data_end = card_data + CARDS_PER_BLOCK;
1882 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)) {
1884 int idx = card_data - card_base;
1885 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
1886 char *end = start + CARD_SIZE_IN_BYTES;
1889 HEAVY_STAT (++scanned_cards);
1894 HEAVY_STAT (++marked_cards);
1896 sgen_card_table_prepare_card_for_scanning (card_data);
1901 index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
1903 obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
1905 if (MS_OBJ_ALLOCED_FAST (obj, block_start)) {
1906 HEAVY_STAT (++scanned_objects);
1907 scan_func (obj, queue);
1909 obj += block_obj_size;
1913 } END_FOREACH_BLOCK;
1918 major_is_worker_thread (pthread_t thread)
1920 if (concurrent_sweep)
1921 return thread == ms_sweep_thread;
1927 alloc_free_block_lists (MSBlockInfo ***lists)
1930 for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
1931 lists [i] = mono_sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
1934 #ifdef SGEN_PARALLEL_MARK
1936 major_alloc_worker_data (void)
1938 /* FIXME: free this when the workers come down */
1939 MSBlockInfo ***lists = malloc (sizeof (MSBlockInfo**) * MS_BLOCK_TYPE_MAX);
1940 alloc_free_block_lists (lists);
1945 major_init_worker_thread (void *data)
1947 MSBlockInfo ***lists = data;
1950 g_assert (lists && lists != free_block_lists);
1951 for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1953 for (j = 0; j < num_block_obj_sizes; ++j)
1954 g_assert (!lists [i][j]);
1957 #ifdef HAVE_KW_THREAD
1958 workers_free_block_lists = data;
1960 pthread_setspecific (workers_free_block_lists_key, data);
1965 major_reset_worker_data (void *data)
1967 MSBlockInfo ***lists = data;
1969 for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1971 for (j = 0; j < num_block_obj_sizes; ++j)
1972 lists [i][j] = NULL;
1977 #undef pthread_create
1980 post_param_init (void)
1982 if (concurrent_sweep) {
1983 if (pthread_create (&ms_sweep_thread, NULL, ms_sweep_thread_func, NULL)) {
1984 fprintf (stderr, "Error: Could not create sweep thread.\n");
1991 #ifdef SGEN_PARALLEL_MARK
1993 mono_sgen_marksweep_fixed_par_init
1995 mono_sgen_marksweep_par_init
1999 mono_sgen_marksweep_fixed_init
2001 mono_sgen_marksweep_init
2004 (SgenMajorCollector *collector)
2009 mono_sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
2012 num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
2013 block_obj_sizes = mono_sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
2014 ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
2016 evacuate_block_obj_sizes = mono_sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
2017 for (i = 0; i < num_block_obj_sizes; ++i)
2018 evacuate_block_obj_sizes [i] = FALSE;
2023 g_print ("block object sizes:\n");
2024 for (i = 0; i < num_block_obj_sizes; ++i)
2025 g_print ("%d\n", block_obj_sizes [i]);
2029 alloc_free_block_lists (free_block_lists);
2031 for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
2032 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
2033 for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
2034 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
2036 LOCK_INIT (ms_block_list_mutex);
2038 mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
2039 mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
2040 mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
2041 mono_counters_register ("Wait for sweep time", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_time_wait_for_sweep);
2042 #ifdef SGEN_PARALLEL_MARK
2043 mono_counters_register ("Slots allocated in vain", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_slots_allocated_in_vain);
2045 #ifndef HAVE_KW_THREAD
2046 pthread_key_create (&workers_free_block_lists_key, NULL);
2051 * FIXME: These are superfluous if concurrent sweep is
2052 * disabled. We might want to create them lazily.
2054 MONO_SEM_INIT (&ms_sweep_cmd_semaphore, 0);
2055 MONO_SEM_INIT (&ms_sweep_done_semaphore, 0);
2057 collector->section_size = MAJOR_SECTION_SIZE;
2058 #ifdef SGEN_PARALLEL_MARK
2059 collector->is_parallel = TRUE;
2060 collector->alloc_worker_data = major_alloc_worker_data;
2061 collector->init_worker_thread = major_init_worker_thread;
2062 collector->reset_worker_data = major_reset_worker_data;
2064 collector->is_parallel = FALSE;
2066 collector->supports_cardtable = TRUE;
2068 collector->have_swept = &have_swept;
2070 collector->alloc_heap = major_alloc_heap;
2071 collector->is_object_live = major_is_object_live;
2072 collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2073 collector->alloc_degraded = major_alloc_degraded;
2074 collector->copy_or_mark_object = major_copy_or_mark_object;
2075 collector->alloc_object = major_alloc_object;
2076 collector->free_pinned_object = free_pinned_object;
2077 collector->iterate_objects = major_iterate_objects;
2078 collector->free_non_pinned_object = major_free_non_pinned_object;
2079 collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2080 collector->pin_objects = major_pin_objects;
2081 #ifdef SGEN_HAVE_CARDTABLE
2082 collector->scan_card_table = major_scan_card_table;
2083 collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2085 collector->init_to_space = major_init_to_space;
2086 collector->sweep = major_sweep;
2087 collector->check_scan_starts = major_check_scan_starts;
2088 collector->dump_heap = major_dump_heap;
2089 collector->get_used_size = major_get_used_size;
2090 collector->start_nursery_collection = major_start_nursery_collection;
2091 collector->finish_nursery_collection = major_finish_nursery_collection;
2092 collector->start_major_collection = major_start_major_collection;
2093 collector->finish_major_collection = major_finish_major_collection;
2094 collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2095 collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2096 collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2097 collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2098 collector->get_num_major_sections = get_num_major_sections;
2099 collector->handle_gc_param = major_handle_gc_param;
2100 collector->print_gc_param_usage = major_print_gc_param_usage;
2101 collector->is_worker_thread = major_is_worker_thread;
2102 collector->post_param_init = post_param_init;
2104 FILL_COLLECTOR_COPY_OBJECT (collector);
2105 FILL_COLLECTOR_SCAN_OBJECT (collector);
2107 #ifdef SGEN_HAVE_CARDTABLE
2108 /*cardtable requires major pages to be 8 cards aligned*/
2109 g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);