mono/metadata/sgen-marksweep.c

   1 /*
   2  * sgen-marksweep.c: The Mark & Sweep major collector.
   3  *
   4  * Author:
   5  *      Mark Probst <mark.probst@gmail.com>
   6  *
   7  * Copyright 2009-2010 Novell, Inc.
   8  * Copyright (C) 2012 Xamarin Inc
   9  *
  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;
  13  *
  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.
  18  *
  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.
  22  */
  23
  24 #include "config.h"
  25
  26 #ifdef HAVE_SGEN_GC
  27
  28 #include <math.h>
  29 #include <errno.h>
  30
  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"
  36
  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/gc-internal.h"
  42
  43 #define MS_BLOCK_SIZE   (16*1024)
  44 #define MS_BLOCK_SIZE_SHIFT     14
  45 #define MAJOR_SECTION_SIZE      MS_BLOCK_SIZE
  46 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
  47
  48 #ifdef FIXED_HEAP
  49 #define MS_DEFAULT_HEAP_NUM_BLOCKS      (32 * 1024) /* 512 MB */
  50 #endif
  51
  52 /*
  53  * Don't allocate single blocks, but alloc a contingent of this many
  54  * blocks in one swoop.
  55  */
  56 #define MS_BLOCK_ALLOC_NUM      32
  57
  58 /*
  59  * Number of bytes before the first object in a block.  At the start
  60  * of a block is the MSBlockHeader, then opional padding, then come
  61  * the objects, so this must be >= sizeof (MSBlockHeader).
  62  */
  63 #ifdef FIXED_HEAP
  64 #define MS_BLOCK_SKIP   0
  65 #else
  66 #define MS_BLOCK_SKIP   16
  67 #endif
  68
  69 #define MS_BLOCK_FREE   (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
  70
  71 #define MS_NUM_MARK_WORDS       ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
  72
  73 #if SGEN_MAX_SMALL_OBJ_SIZE > MS_BLOCK_FREE / 2
  74 #error MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2
  75 #endif
  76
  77 typedef struct _MSBlockInfo MSBlockInfo;
  78 struct _MSBlockInfo {
  79         int obj_size;
  80         int obj_size_index;
  81         int pin_queue_num_entries;
  82         unsigned int pinned : 1;
  83         unsigned int has_references : 1;
  84         unsigned int has_pinned : 1;    /* means cannot evacuate */
  85         unsigned int is_to_space : 1;
  86         unsigned int swept : 1;
  87 #ifdef FIXED_HEAP
  88         unsigned int used : 1;
  89         unsigned int zeroed : 1;
  90 #endif
  91         MSBlockInfo *next;
  92         char *block;
  93         void **free_list;
  94         MSBlockInfo *next_free;
  95         void **pin_queue_start;
  96 #ifdef SGEN_CONCURRENT_MARK
  97         guint8 *cardtable_mod_union;
  98 #endif
  99         mword mark_words [MS_NUM_MARK_WORDS];
 100 };
 101
 102 #ifdef FIXED_HEAP
 103 static mword ms_heap_num_blocks = MS_DEFAULT_HEAP_NUM_BLOCKS;
 104
 105 static char *ms_heap_start;
 106 static char *ms_heap_end;
 107
 108 #define MS_PTR_IN_SMALL_MAJOR_HEAP(p)   ((char*)(p) >= ms_heap_start && (char*)(p) < ms_heap_end)
 109
 110 /* array of all all block infos in the system */
 111 static MSBlockInfo *block_infos;
 112 #endif
 113
 114 #define MS_BLOCK_OBJ(b,i)               ((b)->block + MS_BLOCK_SKIP + (b)->obj_size * (i))
 115 #define MS_BLOCK_OBJ_FOR_SIZE(b,i,obj_size)             ((b)->block + MS_BLOCK_SKIP + (obj_size) * (i))
 116 #define MS_BLOCK_DATA_FOR_OBJ(o)        ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
 117
 118 #ifdef FIXED_HEAP
 119 #define MS_BLOCK_FOR_OBJ(o)             (&block_infos [(mword)((char*)(o) - ms_heap_start) >> MS_BLOCK_SIZE_SHIFT])
 120 #else
 121 typedef struct {
 122         MSBlockInfo *info;
 123 } MSBlockHeader;
 124
 125 #define MS_BLOCK_FOR_OBJ(o)             (((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
 126 #endif
 127
 128 #define MS_BLOCK_OBJ_INDEX(o,b) (((char*)(o) - ((b)->block + MS_BLOCK_SKIP)) / (b)->obj_size)
 129
 130 #define MS_CALC_MARK_BIT(w,b,o)         do {                            \
 131                 int i = ((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o))) >> SGEN_ALLOC_ALIGN_BITS; \
 132                 if (sizeof (mword) == 4) {                              \
 133                         (w) = i >> 5;                                   \
 134                         (b) = i & 31;                                   \
 135                 } else {                                                \
 136                         (w) = i >> 6;                                   \
 137                         (b) = i & 63;                                   \
 138                 }                                                       \
 139         } while (0)
 140
 141 #define MS_MARK_BIT(bl,w,b)     ((bl)->mark_words [(w)] & (1L << (b)))
 142 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (1L << (b)))
 143 #define MS_PAR_SET_MARK_BIT(was_marked,bl,w,b)  do {                    \
 144                 mword __old = (bl)->mark_words [(w)];                   \
 145                 mword __bitmask = 1L << (b);                            \
 146                 if (__old & __bitmask) {                                \
 147                         was_marked = TRUE;                              \
 148                         break;                                          \
 149                 }                                                       \
 150                 if (SGEN_CAS_PTR ((gpointer*)&(bl)->mark_words [(w)],   \
 151                                                 (gpointer)(__old | __bitmask), \
 152                                                 (gpointer)__old) ==     \
 153                                 (gpointer)__old) {                      \
 154                         was_marked = FALSE;                             \
 155                         break;                                          \
 156                 }                                                       \
 157         } while (1)
 158
 159 #define MS_OBJ_ALLOCED(o,b)     (*(void**)(o) && (*(char**)(o) < (b)->block || *(char**)(o) >= (b)->block + MS_BLOCK_SIZE))
 160
 161 #define MS_BLOCK_OBJ_SIZE_FACTOR        (sqrt (2.0))
 162
 163 /*
 164  * This way we can lookup block object size indexes for sizes up to
 165  * 256 bytes with a single load.
 166  */
 167 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES      32
 168
 169 static int *block_obj_sizes;
 170 static int num_block_obj_sizes;
 171 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
 172
 173 #define MS_BLOCK_FLAG_PINNED    1
 174 #define MS_BLOCK_FLAG_REFS      2
 175
 176 #define MS_BLOCK_TYPE_MAX       4
 177
 178 #ifdef SGEN_PARALLEL_MARK
 179 static LOCK_DECLARE (ms_block_list_mutex);
 180 #define LOCK_MS_BLOCK_LIST mono_mutex_lock (&ms_block_list_mutex)
 181 #define UNLOCK_MS_BLOCK_LIST mono_mutex_unlock (&ms_block_list_mutex)
 182 #endif
 183
 184 static gboolean *evacuate_block_obj_sizes;
 185 static float evacuation_threshold = 0.666;
 186
 187 static gboolean concurrent_sweep = FALSE;
 188 static gboolean lazy_sweep = TRUE;
 189 static gboolean have_swept;
 190
 191 /* all allocated blocks in the system */
 192 static MSBlockInfo *all_blocks;
 193
 194 #ifdef FIXED_HEAP
 195 /* non-allocated block free-list */
 196 static MSBlockInfo *empty_blocks = NULL;
 197 #else
 198 /* non-allocated block free-list */
 199 static void *empty_blocks = NULL;
 200 static int num_empty_blocks = 0;
 201 #endif
 202
 203 #define FOREACH_BLOCK(bl)       for ((bl) = all_blocks; (bl); (bl) = (bl)->next) {
 204 #define END_FOREACH_BLOCK       }
 205
 206 static int num_major_sections = 0;
 207 /* one free block list for each block object size */
 208 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
 209
 210 #ifdef SGEN_PARALLEL_MARK
 211 #ifdef HAVE_KW_THREAD
 212 static __thread MSBlockInfo ***workers_free_block_lists;
 213 #else
 214 static MonoNativeTlsKey workers_free_block_lists_key;
 215 #endif
 216 #endif
 217
 218 static long long stat_major_blocks_alloced = 0;
 219 static long long stat_major_blocks_freed = 0;
 220 static long long stat_major_blocks_lazy_swept = 0;
 221 static long long stat_major_objects_evacuated = 0;
 222 static long long stat_time_wait_for_sweep = 0;
 223
 224 static gboolean ms_sweep_in_progress = FALSE;
 225 static MonoNativeThreadId ms_sweep_thread;
 226 static MonoSemType ms_sweep_cmd_semaphore;
 227 static MonoSemType ms_sweep_done_semaphore;
 228
 229 static void
 230 sweep_block (MSBlockInfo *block);
 231
 232 static void
 233 ms_signal_sweep_command (void)
 234 {
 235         if (!concurrent_sweep)
 236                 return;
 237
 238         g_assert (!ms_sweep_in_progress);
 239         ms_sweep_in_progress = TRUE;
 240         MONO_SEM_POST (&ms_sweep_cmd_semaphore);
 241 }
 242
 243 static void
 244 ms_signal_sweep_done (void)
 245 {
 246         if (!concurrent_sweep)
 247                 return;
 248
 249         MONO_SEM_POST (&ms_sweep_done_semaphore);
 250 }
 251
 252 static void
 253 ms_wait_for_sweep_done (void)
 254 {
 255         SGEN_TV_DECLARE (atv);
 256         SGEN_TV_DECLARE (btv);
 257         int result;
 258
 259         if (!concurrent_sweep)
 260                 return;
 261
 262         if (!ms_sweep_in_progress)
 263                 return;
 264
 265         SGEN_TV_GETTIME (atv);
 266         while ((result = MONO_SEM_WAIT (&ms_sweep_done_semaphore)) != 0) {
 267                 if (errno != EINTR)
 268                         g_error ("MONO_SEM_WAIT");
 269         }
 270         SGEN_TV_GETTIME (btv);
 271         stat_time_wait_for_sweep += SGEN_TV_ELAPSED (atv, btv);
 272
 273         g_assert (ms_sweep_in_progress);
 274         ms_sweep_in_progress = FALSE;
 275 }
 276
 277 static int
 278 ms_find_block_obj_size_index (int size)
 279 {
 280         int i;
 281         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);
 282         for (i = 0; i < num_block_obj_sizes; ++i)
 283                 if (block_obj_sizes [i] >= size)
 284                         return i;
 285         g_error ("no object of size %d\n", size);
 286 }
 287
 288 #define FREE_BLOCKS_FROM(lists,p,r)     (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
 289 #define FREE_BLOCKS(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 290 #ifdef SGEN_PARALLEL_MARK
 291 #ifdef HAVE_KW_THREAD
 292 #define FREE_BLOCKS_LOCAL(p,r)          (FREE_BLOCKS_FROM (workers_free_block_lists, (p), (r)))
 293 #else
 294 #define FREE_BLOCKS_LOCAL(p,r)          (FREE_BLOCKS_FROM (((MSBlockInfo***)(mono_native_tls_get_value (workers_free_block_lists_key))), (p), (r)))
 295 #endif
 296 #else
 297 //#define FREE_BLOCKS_LOCAL(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 298 #endif
 299
 300 #define MS_BLOCK_OBJ_SIZE_INDEX(s)                              \
 301         (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ?      \
 302          fast_block_obj_size_indexes [((s)+7)>>3] :             \
 303          ms_find_block_obj_size_index ((s)))
 304
 305 #ifdef FIXED_HEAP
 306 static void*
 307 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 308 {
 309         char *nursery_start;
 310         mword major_heap_size = ms_heap_num_blocks * MS_BLOCK_SIZE;
 311         mword alloc_size = nursery_size + major_heap_size;
 312         mword i;
 313
 314         g_assert (ms_heap_num_blocks > 0);
 315         g_assert (nursery_size % MS_BLOCK_SIZE == 0);
 316         if (nursery_align)
 317                 g_assert (nursery_align % MS_BLOCK_SIZE == 0);
 318
 319         nursery_start = sgen_alloc_os_memory_aligned (alloc_size, nursery_align ? nursery_align : MS_BLOCK_SIZE, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "heap");
 320         ms_heap_start = nursery_start + nursery_size;
 321         ms_heap_end = ms_heap_start + major_heap_size;
 322
 323         block_infos = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo) * ms_heap_num_blocks, INTERNAL_MEM_MS_BLOCK_INFO, TRUE);
 324
 325         for (i = 0; i < ms_heap_num_blocks; ++i) {
 326                 block_infos [i].block = ms_heap_start + i * MS_BLOCK_SIZE;
 327                 if (i < ms_heap_num_blocks - 1)
 328                         block_infos [i].next_free = &block_infos [i + 1];
 329                 else
 330                         block_infos [i].next_free = NULL;
 331                 block_infos [i].zeroed = TRUE;
 332         }
 333
 334         empty_blocks = &block_infos [0];
 335
 336         return nursery_start;
 337 }
 338 #else
 339 static void*
 340 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 341 {
 342         char *start;
 343         if (nursery_align)
 344                 start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 345         else
 346                 start = sgen_alloc_os_memory (nursery_size, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 347
 348         return start;
 349 }
 350 #endif
 351
 352 static void
 353 update_heap_boundaries_for_block (MSBlockInfo *block)
 354 {
 355         sgen_update_heap_boundaries ((mword)block->block, (mword)block->block + MS_BLOCK_SIZE);
 356 }
 357
 358 #ifdef FIXED_HEAP
 359 static MSBlockInfo*
 360 ms_get_empty_block (void)
 361 {
 362         MSBlockInfo *block;
 363
 364         g_assert (empty_blocks);
 365
 366         do {
 367                 block = empty_blocks;
 368         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block->next_free, block) != block);
 369
 370         block->used = TRUE;
 371
 372         if (!block->zeroed)
 373                 memset (block->block, 0, MS_BLOCK_SIZE);
 374
 375         return block;
 376 }
 377
 378 static void
 379 ms_free_block (MSBlockInfo *block)
 380 {
 381         block->next_free = empty_blocks;
 382         empty_blocks = block;
 383         block->used = FALSE;
 384         block->zeroed = FALSE;
 385         sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 386 }
 387 #else
 388 static void*
 389 ms_get_empty_block (void)
 390 {
 391         char *p;
 392         int i;
 393         void *block, *empty, *next;
 394
 395  retry:
 396         if (!empty_blocks) {
 397                 p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * MS_BLOCK_ALLOC_NUM, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "major heap section");
 398
 399                 for (i = 0; i < MS_BLOCK_ALLOC_NUM; ++i) {
 400                         block = p;
 401                         /*
 402                          * We do the free list update one after the
 403                          * other so that other threads can use the new
 404                          * blocks as quickly as possible.
 405                          */
 406                         do {
 407                                 empty = empty_blocks;
 408                                 *(void**)block = empty;
 409                         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
 410                         p += MS_BLOCK_SIZE;
 411                 }
 412
 413                 SGEN_ATOMIC_ADD (num_empty_blocks, MS_BLOCK_ALLOC_NUM);
 414
 415                 stat_major_blocks_alloced += MS_BLOCK_ALLOC_NUM;
 416         }
 417
 418         do {
 419                 empty = empty_blocks;
 420                 if (!empty)
 421                         goto retry;
 422                 block = empty;
 423                 next = *(void**)block;
 424         } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
 425
 426         SGEN_ATOMIC_ADD (num_empty_blocks, -1);
 427
 428         *(void**)block = NULL;
 429
 430         g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
 431
 432         return block;
 433 }
 434
 435 static void
 436 ms_free_block (void *block)
 437 {
 438         void *empty;
 439
 440         sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 441         memset (block, 0, MS_BLOCK_SIZE);
 442
 443         do {
 444                 empty = empty_blocks;
 445                 *(void**)block = empty;
 446         } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
 447
 448         SGEN_ATOMIC_ADD (num_empty_blocks, 1);
 449 }
 450 #endif
 451
 452 //#define MARKSWEEP_CONSISTENCY_CHECK
 453
 454 #ifdef MARKSWEEP_CONSISTENCY_CHECK
 455 static void
 456 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
 457 {
 458         MSBlockInfo *b;
 459
 460         for (; block; block = block->next_free) {
 461                 g_assert (block->obj_size == size);
 462                 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
 463
 464                 /* blocks in the free lists must have at least
 465                    one free slot */
 466                 if (block->swept)
 467                         g_assert (block->free_list);
 468
 469 #ifdef FIXED_HEAP
 470                 /* the block must not be in the empty_blocks list */
 471                 for (b = empty_blocks; b; b = b->next_free)
 472                         g_assert (b != block);
 473 #endif
 474                 /* the block must be in the all_blocks list */
 475                 for (b = all_blocks; b; b = b->next) {
 476                         if (b == block)
 477                                 break;
 478                 }
 479                 g_assert (b == block);
 480         }
 481 }
 482
 483 static void
 484 check_empty_blocks (void)
 485 {
 486 #ifndef FIXED_HEAP
 487         void *p;
 488         int i = 0;
 489         for (p = empty_blocks; p; p = *(void**)p)
 490                 ++i;
 491         g_assert (i == num_empty_blocks);
 492 #endif
 493 }
 494
 495 static void
 496 consistency_check (void)
 497 {
 498         MSBlockInfo *block;
 499         int i;
 500
 501         /* check all blocks */
 502         FOREACH_BLOCK (block) {
 503                 int count = MS_BLOCK_FREE / block->obj_size;
 504                 int num_free = 0;
 505                 void **free;
 506
 507 #ifndef FIXED_HEAP
 508                 /* check block header */
 509                 g_assert (((MSBlockHeader*)block->block)->info == block);
 510 #endif
 511
 512                 /* count number of free slots */
 513                 for (i = 0; i < count; ++i) {
 514                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 515                         if (!MS_OBJ_ALLOCED (obj, block))
 516                                 ++num_free;
 517                 }
 518
 519                 /* check free list */
 520                 for (free = block->free_list; free; free = (void**)*free) {
 521                         g_assert (MS_BLOCK_FOR_OBJ (free) == block);
 522                         --num_free;
 523                 }
 524                 g_assert (num_free == 0);
 525
 526                 /* check all mark words are zero */
 527                 if (block->swept) {
 528                         for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
 529                                 g_assert (block->mark_words [i] == 0);
 530                 }
 531         } END_FOREACH_BLOCK;
 532
 533         /* check free blocks */
 534         for (i = 0; i < num_block_obj_sizes; ++i) {
 535                 int j;
 536                 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
 537                         check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
 538         }
 539
 540         check_empty_blocks ();
 541 }
 542 #endif
 543
 544 static gboolean
 545 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
 546 {
 547         int size = block_obj_sizes [size_index];
 548         int count = MS_BLOCK_FREE / size;
 549         MSBlockInfo *info;
 550 #ifdef SGEN_PARALLEL_MARK
 551         MSBlockInfo *next;
 552 #endif
 553 #ifndef FIXED_HEAP
 554         MSBlockHeader *header;
 555 #endif
 556         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 557         char *obj_start;
 558         int i;
 559
 560         if (!sgen_memgov_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
 561                 return FALSE;
 562
 563 #ifdef FIXED_HEAP
 564         info = ms_get_empty_block ();
 565 #else
 566         info = sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
 567 #endif
 568
 569         SGEN_ASSERT (9, count >= 2, "block with %d objects, it must hold at least 2", count);
 570
 571         info->obj_size = size;
 572         info->obj_size_index = size_index;
 573         info->pinned = pinned;
 574         info->has_references = has_references;
 575         info->has_pinned = pinned;
 576         info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD); /*FIXME WHY??? */
 577         info->swept = 1;
 578 #ifndef FIXED_HEAP
 579         info->block = ms_get_empty_block ();
 580
 581         header = (MSBlockHeader*) info->block;
 582         header->info = info;
 583 #endif
 584 #ifdef SGEN_CONCURRENT_MARK
 585         info->cardtable_mod_union = NULL;
 586 #endif
 587
 588         update_heap_boundaries_for_block (info);
 589
 590         /* build free list */
 591         obj_start = info->block + MS_BLOCK_SKIP;
 592         info->free_list = (void**)obj_start;
 593         /* we're skipping the last one - it must be nulled */
 594         for (i = 0; i < count - 1; ++i) {
 595                 char *next_obj_start = obj_start + size;
 596                 *(void**)obj_start = next_obj_start;
 597                 obj_start = next_obj_start;
 598         }
 599         /* the last one */
 600         *(void**)obj_start = NULL;
 601
 602 #ifdef SGEN_PARALLEL_MARK
 603         do {
 604                 next = info->next_free = free_blocks [size_index];
 605         } while (SGEN_CAS_PTR ((void**)&free_blocks [size_index], info, next) != next);
 606
 607         do {
 608                 next = info->next = all_blocks;
 609         } while (SGEN_CAS_PTR ((void**)&all_blocks, info, next) != next);
 610 #else
 611         info->next_free = free_blocks [size_index];
 612         free_blocks [size_index] = info;
 613
 614         info->next = all_blocks;
 615         all_blocks = info;
 616 #endif
 617
 618         ++num_major_sections;
 619         return TRUE;
 620 }
 621
 622 static gboolean
 623 obj_is_from_pinned_alloc (char *ptr)
 624 {
 625         MSBlockInfo *block;
 626
 627         FOREACH_BLOCK (block) {
 628                 if (ptr >= block->block && ptr <= block->block + MS_BLOCK_SIZE)
 629                         return block->pinned;
 630         } END_FOREACH_BLOCK;
 631         return FALSE;
 632 }
 633
 634 static void*
 635 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
 636 {
 637         MSBlockInfo *block;
 638         void *obj;
 639
 640         block = free_blocks [size_index];
 641         SGEN_ASSERT (9, block, "no free block to unlink from free_blocks %p size_index %d", free_blocks, size_index);
 642
 643         if (G_UNLIKELY (!block->swept)) {
 644                 stat_major_blocks_lazy_swept ++;
 645                 sweep_block (block);
 646         }
 647
 648         obj = block->free_list;
 649         SGEN_ASSERT (9, obj, "block %p in free list had no available object to alloc from", block);
 650
 651         block->free_list = *(void**)obj;
 652         if (!block->free_list) {
 653                 free_blocks [size_index] = block->next_free;
 654                 block->next_free = NULL;
 655         }
 656
 657         return obj;
 658 }
 659
 660 #ifdef SGEN_PARALLEL_MARK
 661 static gboolean
 662 try_remove_block_from_free_list (MSBlockInfo *block, MSBlockInfo **free_blocks, int size_index)
 663 {
 664         /*
 665          * No more free slots in the block, so try to free the block.
 666          * Don't try again if we don't succeed - another thread will
 667          * already have done it.
 668          */
 669         MSBlockInfo *next_block = block->next_free;
 670         if (SGEN_CAS_PTR ((void**)&free_blocks [size_index], next_block, block) == block) {
 671                 /*
 672                 void *old = SGEN_CAS_PTR ((void**)&block->next_free, NULL, next_block);
 673                 g_assert (old == next_block);
 674                 */
 675                 block->next_free = NULL;
 676                 return TRUE;
 677         }
 678         return FALSE;
 679 }
 680
 681 static void*
 682 alloc_obj_par (MonoVTable *vtable, int size, gboolean pinned, gboolean has_references)
 683 {
 684         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 685         MSBlockInfo **free_blocks_local = FREE_BLOCKS_LOCAL (pinned, has_references);
 686         MSBlockInfo *block;
 687         void *obj;
 688
 689         SGEN_ASSERT (9, !ms_sweep_in_progress, "concurrent sweep in progress with concurrent allocation");
 690         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
 691
 692         if (free_blocks_local [size_index]) {
 693         get_slot:
 694                 obj = unlink_slot_from_free_list_uncontested (free_blocks_local, size_index);
 695         } else {
 696                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 697
 698         get_block:
 699                 block = free_blocks [size_index];
 700                 if (block) {
 701                         if (!try_remove_block_from_free_list (block, free_blocks, size_index))
 702                                 goto get_block;
 703
 704                         g_assert (block->next_free == NULL);
 705                         g_assert (block->free_list);
 706                         block->next_free = free_blocks_local [size_index];
 707                         free_blocks_local [size_index] = block;
 708
 709                         goto get_slot;
 710                 } else {
 711                         gboolean success;
 712
 713                         LOCK_MS_BLOCK_LIST;
 714                         success = ms_alloc_block (size_index, pinned, has_references);
 715                         UNLOCK_MS_BLOCK_LIST;
 716
 717                         if (G_UNLIKELY (!success))
 718                                 return NULL;
 719
 720                         goto get_block;
 721                 }
 722         }
 723
 724         *(MonoVTable**)obj = vtable;
 725
 726 #ifdef SGEN_CONCURRENT_MARK
 727         g_assert_not_reached ();
 728 #endif
 729
 730         return obj;
 731 }
 732
 733 static void*
 734 major_par_alloc_object (MonoVTable *vtable, int size, gboolean has_references)
 735 {
 736         return alloc_obj_par (vtable, size, FALSE, has_references);
 737 }
 738 #endif
 739
 740 static void*
 741 alloc_obj (MonoVTable *vtable, int size, gboolean pinned, gboolean has_references)
 742 {
 743         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 744         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 745         void *obj;
 746
 747 #ifdef SGEN_PARALLEL_MARK
 748         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
 749
 750 #endif
 751
 752         SGEN_ASSERT (9, !ms_sweep_in_progress, "concurrent sweep in progress with concurrent allocation");
 753
 754         if (!free_blocks [size_index]) {
 755                 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
 756                         return NULL;
 757         }
 758
 759         obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
 760
 761         *(MonoVTable**)obj = vtable;
 762
 763 #ifdef SGEN_CONCURRENT_MARK
 764         if (obj && sgen_remember_major_object_for_concurrent_mark (obj)) {
 765                 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 766                 int word, bit;
 767                 MS_CALC_MARK_BIT (word, bit, obj);
 768                 MS_SET_MARK_BIT (block, word, bit);
 769                 binary_protocol_mark (obj, NULL, size);
 770         }
 771 #endif
 772
 773         return obj;
 774 }
 775
 776 static void*
 777 major_alloc_object (MonoVTable *vtable, int size, gboolean has_references)
 778 {
 779         return alloc_obj (vtable, size, FALSE, has_references);
 780 }
 781
 782 /*
 783  * We're not freeing the block if it's empty.  We leave that work for
 784  * the next major collection.
 785  *
 786  * This is just called from the domain clearing code, which runs in a
 787  * single thread and has the GC lock, so we don't need an extra lock.
 788  */
 789 static void
 790 free_object (char *obj, size_t size, gboolean pinned)
 791 {
 792         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 793         int word, bit;
 794
 795         if (!block->swept)
 796                 sweep_block (block);
 797         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);
 798         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p is already free", obj);
 799         MS_CALC_MARK_BIT (word, bit, obj);
 800         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p has mark bit set");
 801         if (!block->free_list) {
 802                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
 803                 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 804                 SGEN_ASSERT (9, !block->next_free, "block %p doesn't have a free-list of object but belongs to a free-list of blocks");
 805                 block->next_free = free_blocks [size_index];
 806                 free_blocks [size_index] = block;
 807         }
 808         memset (obj, 0, size);
 809         *(void**)obj = block->free_list;
 810         block->free_list = (void**)obj;
 811 }
 812
 813 static void
 814 major_free_non_pinned_object (char *obj, size_t size)
 815 {
 816         free_object (obj, size, FALSE);
 817 }
 818
 819 /* size is a multiple of SGEN_ALLOC_ALIGN */
 820 static void*
 821 major_alloc_small_pinned_obj (MonoVTable *vtable, size_t size, gboolean has_references)
 822 {
 823         void *res;
 824
 825         ms_wait_for_sweep_done ();
 826
 827         res = alloc_obj (vtable, size, TRUE, has_references);
 828          /*If we failed to alloc memory, we better try releasing memory
 829           *as pinned alloc is requested by the runtime.
 830           */
 831          if (!res) {
 832                 sgen_perform_collection (0, GENERATION_OLD, "pinned alloc failure", TRUE);
 833                 res = alloc_obj (vtable, size, TRUE, has_references);
 834          }
 835          return res;
 836 }
 837
 838 static void
 839 free_pinned_object (char *obj, size_t size)
 840 {
 841         free_object (obj, size, TRUE);
 842 }
 843
 844 /*
 845  * size is already rounded up and we hold the GC lock.
 846  */
 847 static void*
 848 major_alloc_degraded (MonoVTable *vtable, size_t size)
 849 {
 850         void *obj;
 851         int old_num_sections;
 852
 853         ms_wait_for_sweep_done ();
 854
 855         old_num_sections = num_major_sections;
 856
 857         obj = alloc_obj (vtable, size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
 858         if (G_LIKELY (obj)) {
 859                 HEAVY_STAT (++stat_objects_alloced_degraded);
 860                 HEAVY_STAT (stat_bytes_alloced_degraded += size);
 861                 g_assert (num_major_sections >= old_num_sections);
 862                 sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
 863         }
 864         return obj;
 865 }
 866
 867 #define MAJOR_OBJ_IS_IN_TO_SPACE(obj)   FALSE
 868
 869 /*
 870  * obj is some object.  If it's not in the major heap (i.e. if it's in
 871  * the nursery or LOS), return FALSE.  Otherwise return whether it's
 872  * been marked or copied.
 873  */
 874 static gboolean
 875 major_is_object_live (char *obj)
 876 {
 877         MSBlockInfo *block;
 878         int word, bit;
 879 #ifndef FIXED_HEAP
 880         mword objsize;
 881 #endif
 882
 883         if (sgen_ptr_in_nursery (obj))
 884                 return FALSE;
 885
 886 #ifdef FIXED_HEAP
 887         /* LOS */
 888         if (!MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
 889                 return FALSE;
 890 #else
 891         objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 892
 893         /* LOS */
 894         if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
 895                 return FALSE;
 896 #endif
 897
 898         /* now we know it's in a major block */
 899         block = MS_BLOCK_FOR_OBJ (obj);
 900         SGEN_ASSERT (9, !block->pinned, "block %p is pinned, BTW why is this bad?");
 901         MS_CALC_MARK_BIT (word, bit, obj);
 902         return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
 903 }
 904
 905 static gboolean
 906 major_ptr_is_in_non_pinned_space (char *ptr, char **start)
 907 {
 908         MSBlockInfo *block;
 909
 910         FOREACH_BLOCK (block) {
 911                 if (ptr >= block->block && ptr <= block->block + MS_BLOCK_SIZE) {
 912                         int count = MS_BLOCK_FREE / block->obj_size;
 913                         int i;
 914
 915                         *start = NULL;
 916                         for (i = 0; i <= count; ++i) {
 917                                 if (ptr >= MS_BLOCK_OBJ (block, i) && ptr < MS_BLOCK_OBJ (block, i + 1)) {
 918                                         *start = MS_BLOCK_OBJ (block, i);
 919                                         break;
 920                                 }
 921                         }
 922                         return !block->pinned;
 923                 }
 924         } END_FOREACH_BLOCK;
 925         return FALSE;
 926 }
 927
 928 static void
 929 major_iterate_objects (gboolean non_pinned, gboolean pinned, IterateObjectCallbackFunc callback, void *data)
 930 {
 931         MSBlockInfo *block;
 932
 933         ms_wait_for_sweep_done ();
 934
 935         FOREACH_BLOCK (block) {
 936                 int count = MS_BLOCK_FREE / block->obj_size;
 937                 int i;
 938
 939                 if (block->pinned && !pinned)
 940                         continue;
 941                 if (!block->pinned && !non_pinned)
 942                         continue;
 943                 if (lazy_sweep)
 944                         sweep_block (block);
 945
 946                 for (i = 0; i < count; ++i) {
 947                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 948                         if (MS_OBJ_ALLOCED (obj, block))
 949                                 callback ((char*)obj, block->obj_size, data);
 950                 }
 951         } END_FOREACH_BLOCK;
 952 }
 953
 954 static gboolean
 955 major_is_valid_object (char *object)
 956 {
 957         MSBlockInfo *block;
 958
 959         ms_wait_for_sweep_done ();
 960         FOREACH_BLOCK (block) {
 961                 int idx;
 962                 char *obj;
 963
 964                 if ((block->block > object) || ((block->block + MS_BLOCK_SIZE) <= object))
 965                         continue;
 966
 967                 idx = MS_BLOCK_OBJ_INDEX (object, block);
 968                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 969                 if (obj != object)
 970                         return FALSE;
 971                 return MS_OBJ_ALLOCED (obj, block);
 972         } END_FOREACH_BLOCK;
 973
 974         return FALSE;
 975 }
 976
 977
 978 static gboolean
 979 major_describe_pointer (char *ptr)
 980 {
 981         MSBlockInfo *block;
 982
 983         FOREACH_BLOCK (block) {
 984                 int idx;
 985                 char *obj;
 986                 gboolean live;
 987                 MonoVTable *vtable;
 988
 989                 if ((block->block > ptr) || ((block->block + MS_BLOCK_SIZE) <= ptr))
 990                         continue;
 991
 992                 SGEN_LOG (1, "major-ptr (block %p sz %d pin %d ref %d) ",
 993                         block->block, block->obj_size, block->pinned, block->has_references);
 994
 995                 idx = MS_BLOCK_OBJ_INDEX (ptr, block);
 996                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 997                 live = MS_OBJ_ALLOCED (obj, block);
 998                 vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
 999
1000                 if (obj == ptr) {
1001                         if (live)
1002                                 SGEN_LOG (1, "\t(object %s.%s)", vtable->klass->name_space, vtable->klass->name);
1003                         else
1004                                 SGEN_LOG (1, "(dead-object)");
1005                 } else {
1006                         if (live)
1007                                 SGEN_LOG (1, "(interior-ptr offset %td of %p %s.%s)",
1008                                         ptr - obj,
1009                                         obj, vtable->klass->name_space, vtable->klass->name);
1010                         else
1011                                 SGEN_LOG (1, "(dead-interior-ptr to %td to %p)",
1012                                         ptr - obj, obj);
1013                 }
1014
1015                 return TRUE;
1016         } END_FOREACH_BLOCK;
1017
1018         return FALSE;
1019 }
1020
1021 static void
1022 major_check_scan_starts (void)
1023 {
1024 }
1025
1026 static void
1027 major_dump_heap (FILE *heap_dump_file)
1028 {
1029         MSBlockInfo *block;
1030         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1031         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1032         int i;
1033
1034         for (i = 0; i < num_block_obj_sizes; ++i)
1035                 slots_available [i] = slots_used [i] = 0;
1036
1037         FOREACH_BLOCK (block) {
1038                 int index = ms_find_block_obj_size_index (block->obj_size);
1039                 int count = MS_BLOCK_FREE / block->obj_size;
1040
1041                 slots_available [index] += count;
1042                 for (i = 0; i < count; ++i) {
1043                         if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
1044                                 ++slots_used [index];
1045                 }
1046         } END_FOREACH_BLOCK;
1047
1048         fprintf (heap_dump_file, "<occupancies>\n");
1049         for (i = 0; i < num_block_obj_sizes; ++i) {
1050                 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
1051                                 block_obj_sizes [i], slots_available [i], slots_used [i]);
1052         }
1053         fprintf (heap_dump_file, "</occupancies>\n");
1054
1055         FOREACH_BLOCK (block) {
1056                 int count = MS_BLOCK_FREE / block->obj_size;
1057                 int i;
1058                 int start = -1;
1059
1060                 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
1061
1062                 for (i = 0; i <= count; ++i) {
1063                         if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
1064                                 if (start < 0)
1065                                         start = i;
1066                         } else {
1067                                 if (start >= 0) {
1068                                         sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), block->block);
1069                                         start = -1;
1070                                 }
1071                         }
1072                 }
1073
1074                 fprintf (heap_dump_file, "</section>\n");
1075         } END_FOREACH_BLOCK;
1076 }
1077
1078 #define LOAD_VTABLE     SGEN_LOAD_VTABLE
1079
1080 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,block,queue) do {        \
1081                 int __word, __bit;                                      \
1082                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
1083                 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
1084                         MS_SET_MARK_BIT ((block), __word, __bit);       \
1085                         if ((block)->has_references)                    \
1086                                 GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
1087                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
1088                 }                                                       \
1089         } while (0)
1090 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do {                \
1091                 int __word, __bit;                                      \
1092                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
1093                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj);       \
1094                 if (!MS_MARK_BIT ((block), __word, __bit)) {            \
1095                         MS_SET_MARK_BIT ((block), __word, __bit);       \
1096                         if ((block)->has_references)                    \
1097                                 GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
1098                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
1099                 }                                                       \
1100         } while (0)
1101 #define MS_PAR_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do {            \
1102                 int __word, __bit;                                      \
1103                 gboolean __was_marked;                                  \
1104                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj);       \
1105                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
1106                 MS_PAR_SET_MARK_BIT (__was_marked, (block), __word, __bit); \
1107                 if (!__was_marked) {                                    \
1108                         if ((block)->has_references)                    \
1109                                 GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
1110                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
1111                 }                                                       \
1112         } while (0)
1113
1114 static void
1115 pin_major_object (char *obj, SgenGrayQueue *queue)
1116 {
1117 #ifdef SGEN_CONCURRENT_MARK
1118         g_assert_not_reached ();
1119 #else
1120         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1121         block->has_pinned = TRUE;
1122         MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1123 #endif
1124 }
1125
1126 #include "sgen-major-copy-object.h"
1127
1128 #ifdef SGEN_PARALLEL_MARK
1129 static void
1130 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1131 {
1132         void *obj = *ptr;
1133         mword objsize;
1134         MSBlockInfo *block;
1135         MonoVTable *vt;
1136
1137         HEAVY_STAT (++stat_copy_object_called_major);
1138
1139         SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
1140         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
1141
1142         if (sgen_ptr_in_nursery (obj)) {
1143                 int word, bit;
1144                 gboolean has_references;
1145                 void *destination;
1146                 mword vtable_word = *(mword*)obj;
1147                 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1148
1149                 if (vtable_word & SGEN_FORWARDED_BIT) {
1150                         *ptr = (void*)vt;
1151                         return;
1152                 }
1153
1154                 if (vtable_word & SGEN_PINNED_BIT)
1155                         return;
1156
1157                 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
1158                 if (sgen_nursery_is_to_space (obj))
1159                         return;
1160
1161                 HEAVY_STAT (++stat_objects_copied_major);
1162
1163         do_copy_object:
1164                 objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
1165                 has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
1166
1167                 destination = sgen_minor_collector.par_alloc_for_promotion (vt, obj, objsize, has_references);
1168                 if (G_UNLIKELY (!destination)) {
1169                         if (!sgen_ptr_in_nursery (obj)) {
1170                                 int size_index;
1171                                 block = MS_BLOCK_FOR_OBJ (obj);
1172                                 size_index = block->obj_size_index;
1173                                 evacuate_block_obj_sizes [size_index] = FALSE;
1174                         }
1175
1176                         sgen_parallel_pin_or_update (ptr, obj, vt, queue);
1177                         sgen_set_pinned_from_failed_allocation (objsize);
1178                         return;
1179                 }
1180
1181                 if (SGEN_CAS_PTR (obj, (void*)((mword)destination | SGEN_FORWARDED_BIT), vt) == vt) {
1182                         gboolean was_marked;
1183
1184                         par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
1185                         obj = destination;
1186                         *ptr = obj;
1187
1188                         /*
1189                          * FIXME: If we make major_alloc_object() give
1190                          * us the block info, too, we won't have to
1191                          * re-fetch it here.
1192                          *
1193                          * FIXME (2): We should rework this to avoid all those nursery checks.
1194                          */
1195                         /*
1196                          * For the split nursery allocator the object
1197                          * might still be in the nursery despite
1198                          * having being promoted, in which case we
1199                          * can't mark it.
1200                          */
1201                         if (!sgen_ptr_in_nursery (obj)) {
1202                                 block = MS_BLOCK_FOR_OBJ (obj);
1203                                 MS_CALC_MARK_BIT (word, bit, obj);
1204                                 SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
1205                                 MS_PAR_SET_MARK_BIT (was_marked, block, word, bit);
1206                         }
1207                 } else {
1208                         /*
1209                          * FIXME: We have allocated destination, but
1210                          * we cannot use it.  Give it back to the
1211                          * allocator.
1212                          */
1213                         *(void**)destination = NULL;
1214
1215                         vtable_word = *(mword*)obj;
1216                         g_assert (vtable_word & SGEN_FORWARDED_BIT);
1217
1218                         obj = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1219
1220                         *ptr = obj;
1221
1222                         HEAVY_STAT (++stat_slots_allocated_in_vain);
1223                 }
1224         } else {
1225 #ifdef FIXED_HEAP
1226                 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1227 #else
1228                 mword vtable_word = *(mword*)obj;
1229                 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1230
1231                 /* see comment in the non-parallel version below */
1232                 if (vtable_word & SGEN_FORWARDED_BIT) {
1233                         *ptr = (void*)vt;
1234                         return;
1235                 }
1236                 objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
1237
1238                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1239 #endif
1240                 {
1241                         int size_index;
1242
1243                         block = MS_BLOCK_FOR_OBJ (obj);
1244                         size_index = block->obj_size_index;
1245
1246                         if (!block->has_pinned && evacuate_block_obj_sizes [size_index]) {
1247                                 if (block->is_to_space)
1248                                         return;
1249
1250 #ifdef FIXED_HEAP
1251                                 {
1252                                         mword vtable_word = *(mword*)obj;
1253                                         vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1254
1255                                         if (vtable_word & SGEN_FORWARDED_BIT) {
1256                                                 *ptr = (void*)vt;
1257                                                 return;
1258                                         }
1259                                 }
1260 #endif
1261
1262                                 HEAVY_STAT (++stat_major_objects_evacuated);
1263                                 goto do_copy_object;
1264                         }
1265
1266                         MS_PAR_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1267                 } else {
1268                         LOSObject *bigobj = sgen_los_header_for_object (obj);
1269                         mword size_word = bigobj->size;
1270
1271                         if (size_word & 1)
1272                                 return;
1273                         binary_protocol_pin (obj, vt, sgen_safe_object_get_size ((MonoObject*)obj));
1274                         if (SGEN_CAS_PTR ((void*)&bigobj->size, (void*)(size_word | 1), (void*)size_word) == (void*)size_word) {
1275                                 if (SGEN_VTABLE_HAS_REFERENCES (vt))
1276                                         GRAY_OBJECT_ENQUEUE (queue, obj);
1277                         } else {
1278                                 g_assert (sgen_los_object_is_pinned (obj));
1279                         }
1280                 }
1281         }
1282 }
1283 #else
1284 #ifdef SGEN_CONCURRENT_MARK
1285 static void
1286 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1287 {
1288         void *obj = *ptr;
1289
1290         g_assert (!SGEN_OBJECT_IS_FORWARDED (obj));
1291
1292         if (sgen_ptr_in_nursery (obj)) {
1293                 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1294         } else {
1295 #ifdef FIXED_HEAP
1296                 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1297 #else
1298                 mword objsize;
1299
1300                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
1301
1302                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1303 #endif
1304                 {
1305                         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1306                         MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1307                 } else {
1308                         if (sgen_los_object_is_pinned (obj))
1309                                 return;
1310                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1311                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
1312                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
1313                         }
1314                         sgen_los_pin_object (obj);
1315                         /* FIXME: only enqueue if object has references */
1316                         GRAY_OBJECT_ENQUEUE (queue, obj);
1317                 }
1318         }
1319 }
1320 #else
1321 static void
1322 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1323 {
1324         void *obj = *ptr;
1325         MSBlockInfo *block;
1326
1327         HEAVY_STAT (++stat_copy_object_called_major);
1328
1329         SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
1330         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
1331
1332         if (sgen_ptr_in_nursery (obj)) {
1333                 int word, bit;
1334                 char *forwarded, *old_obj;
1335
1336                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1337                         *ptr = forwarded;
1338                         return;
1339                 }
1340                 if (SGEN_OBJECT_IS_PINNED (obj))
1341                         return;
1342
1343                 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
1344                 if (sgen_nursery_is_to_space (obj))
1345                         return;
1346
1347                 HEAVY_STAT (++stat_objects_copied_major);
1348
1349         do_copy_object:
1350                 old_obj = obj;
1351                 obj = copy_object_no_checks (obj, queue);
1352                 if (G_UNLIKELY (old_obj == obj)) {
1353                         /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
1354                         if (!sgen_ptr_in_nursery (obj)) {
1355                                 int size_index;
1356                                 block = MS_BLOCK_FOR_OBJ (obj);
1357                                 size_index = block->obj_size_index;
1358                                 evacuate_block_obj_sizes [size_index] = FALSE;
1359                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1360                         }
1361                         return;
1362                 }
1363                 *ptr = obj;
1364
1365                 /*
1366                  * FIXME: See comment for copy_object_no_checks().  If
1367                  * we have that, we can let the allocation function
1368                  * give us the block info, too, and we won't have to
1369                  * re-fetch it.
1370                  *
1371                  * FIXME (2): We should rework this to avoid all those nursery checks.
1372                  */
1373                 /*
1374                  * For the split nursery allocator the object might
1375                  * still be in the nursery despite having being
1376                  * promoted, in which case we can't mark it.
1377                  */
1378                 if (!sgen_ptr_in_nursery (obj)) {
1379                         block = MS_BLOCK_FOR_OBJ (obj);
1380                         MS_CALC_MARK_BIT (word, bit, obj);
1381                         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
1382                         MS_SET_MARK_BIT (block, word, bit);
1383                 }
1384         } else {
1385                 char *forwarded;
1386 #ifdef FIXED_HEAP
1387                 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1388 #else
1389                 mword objsize;
1390
1391                 /*
1392                  * If we have don't have a fixed heap we cannot know
1393                  * whether an object is in the LOS or in the small
1394                  * object major heap without checking its size.  To do
1395                  * that, however, we need to know that we actually
1396                  * have a valid object, not a forwarding pointer, so
1397                  * we have to do this check first.
1398                  */
1399                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1400                         *ptr = forwarded;
1401                         return;
1402                 }
1403
1404                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
1405
1406                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1407 #endif
1408                 {
1409                         int size_index;
1410                         gboolean evacuate;
1411
1412                         block = MS_BLOCK_FOR_OBJ (obj);
1413                         size_index = block->obj_size_index;
1414                         evacuate = evacuate_block_obj_sizes [size_index];
1415
1416 #ifdef FIXED_HEAP
1417                         /*
1418                          * We could also check for !block->has_pinned
1419                          * here, but it would only make an uncommon case
1420                          * faster, namely objects that are in blocks
1421                          * whose slot sizes are evacuated but which have
1422                          * pinned objects.
1423                          */
1424                         if (evacuate && (forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1425                                 *ptr = forwarded;
1426                                 return;
1427                         }
1428 #endif
1429
1430                         if (evacuate && !block->has_pinned) {
1431                                 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1432                                 if (block->is_to_space)
1433                                         return;
1434                                 HEAVY_STAT (++stat_major_objects_evacuated);
1435                                 goto do_copy_object;
1436                         } else {
1437                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1438                         }
1439                 } else {
1440                         if (sgen_los_object_is_pinned (obj))
1441                                 return;
1442                         binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1443                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1444                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
1445                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
1446                         }
1447                         sgen_los_pin_object (obj);
1448                         /* FIXME: only enqueue if object has references */
1449                         GRAY_OBJECT_ENQUEUE (queue, obj);
1450                 }
1451         }
1452 }
1453 #endif
1454 #endif
1455
1456 #include "sgen-major-scan-object.h"
1457
1458 static void
1459 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
1460 {
1461         int i;
1462         int last_index = -1;
1463
1464         if (!block->pin_queue_num_entries)
1465                 return;
1466
1467         block->has_pinned = TRUE;
1468
1469         for (i = 0; i < block->pin_queue_num_entries; ++i) {
1470                 int index = MS_BLOCK_OBJ_INDEX (block->pin_queue_start [i], block);
1471                 SGEN_ASSERT (9, index >= 0 && index < MS_BLOCK_FREE / block->obj_size, "invalid object %p index %d max-index %d", block->pin_queue_start [i], index, MS_BLOCK_FREE / block->obj_size);
1472                 if (index == last_index)
1473                         continue;
1474                 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (MS_BLOCK_OBJ (block, index), block, queue);
1475                 last_index = index;
1476         }
1477 }
1478
1479 static inline void
1480 sweep_block_for_size (MSBlockInfo *block, int count, int obj_size)
1481 {
1482         int obj_index;
1483
1484         for (obj_index = 0; obj_index < count; ++obj_index) {
1485                 int word, bit;
1486                 void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, obj_index, obj_size);
1487
1488                 MS_CALC_MARK_BIT (word, bit, obj);
1489                 if (MS_MARK_BIT (block, word, bit)) {
1490                         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p not allocated", obj);
1491                 } else {
1492                         /* an unmarked object */
1493                         if (MS_OBJ_ALLOCED (obj, block)) {
1494                                 /*
1495                                  * FIXME: Merge consecutive
1496                                  * slots for lower reporting
1497                                  * overhead.  Maybe memset
1498                                  * will also benefit?
1499                                  */
1500                                 binary_protocol_empty (obj, obj_size);
1501                                 MONO_GC_MAJOR_SWEPT ((mword)obj, obj_size);
1502                                 memset (obj, 0, obj_size);
1503                         }
1504                         *(void**)obj = block->free_list;
1505                         block->free_list = obj;
1506                 }
1507         }
1508 }
1509
1510 /*
1511  * sweep_block:
1512  *
1513  *   Traverse BLOCK, freeing and zeroing unused objects.
1514  */
1515 static void
1516 sweep_block (MSBlockInfo *block)
1517 {
1518         int count;
1519
1520         if (block->swept)
1521                 return;
1522
1523         count = MS_BLOCK_FREE / block->obj_size;
1524
1525         block->free_list = NULL;
1526
1527         /* Use inline instances specialized to constant sizes, this allows the compiler to replace the memset calls with inline code */
1528         // FIXME: Add more sizes
1529         switch (block->obj_size) {
1530         case 16:
1531                 sweep_block_for_size (block, count, 16);
1532                 break;
1533         default:
1534                 sweep_block_for_size (block, count, block->obj_size);
1535                 break;
1536         }
1537
1538         /* reset mark bits */
1539         memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1540
1541         /*
1542          * FIXME: reverse free list so that it's in address
1543          * order
1544          */
1545
1546         block->swept = 1;
1547 }
1548
1549 static inline int
1550 bitcount (mword d)
1551 {
1552 #if SIZEOF_VOID_P == 8
1553         /* http://www.jjj.de/bitwizardry/bitwizardrypage.html */
1554         d -=  (d>>1) & 0x5555555555555555;
1555         d  = ((d>>2) & 0x3333333333333333) + (d & 0x3333333333333333);
1556         d  = ((d>>4) + d) & 0x0f0f0f0f0f0f0f0f;
1557         d *= 0x0101010101010101;
1558         return d >> 56;
1559 #else
1560         /* http://aggregate.org/MAGIC/ */
1561         d -= ((d >> 1) & 0x55555555);
1562         d = (((d >> 2) & 0x33333333) + (d & 0x33333333));
1563         d = (((d >> 4) + d) & 0x0f0f0f0f);
1564         d += (d >> 8);
1565         d += (d >> 16);
1566         return (d & 0x0000003f);
1567 #endif
1568 }
1569
1570 static void
1571 ms_sweep (void)
1572 {
1573         int i;
1574         MSBlockInfo **iter;
1575
1576         /* statistics for evacuation */
1577         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1578         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1579         int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1580
1581         for (i = 0; i < num_block_obj_sizes; ++i)
1582                 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1583
1584         /* clear all the free lists */
1585         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1586                 MSBlockInfo **free_blocks = free_block_lists [i];
1587                 int j;
1588                 for (j = 0; j < num_block_obj_sizes; ++j)
1589                         free_blocks [j] = NULL;
1590         }
1591
1592         /* traverse all blocks, free and zero unmarked objects */
1593         iter = &all_blocks;
1594         while (*iter) {
1595                 MSBlockInfo *block = *iter;
1596                 int count;
1597                 gboolean have_live = FALSE;
1598                 gboolean has_pinned;
1599                 gboolean have_free = FALSE;
1600                 int obj_size_index;
1601                 int nused = 0;
1602
1603                 obj_size_index = block->obj_size_index;
1604
1605                 has_pinned = block->has_pinned;
1606                 block->has_pinned = block->pinned;
1607
1608                 block->is_to_space = FALSE;
1609                 block->swept = 0;
1610
1611                 count = MS_BLOCK_FREE / block->obj_size;
1612
1613 #ifdef SGEN_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;
1617                 }
1618 #endif
1619
1620                 /* Count marked objects in the block */
1621                 for (i = 0; i < MS_NUM_MARK_WORDS; ++i) {
1622                         nused += bitcount (block->mark_words [i]);
1623                 }
1624                 if (nused) {
1625                         have_live = TRUE;
1626                 }
1627                 if (nused < count)
1628                         have_free = TRUE;
1629
1630                 if (!lazy_sweep)
1631                         sweep_block (block);
1632
1633                 if (have_live) {
1634                         if (!has_pinned) {
1635                                 ++num_blocks [obj_size_index];
1636                                 slots_used [obj_size_index] += nused;
1637                                 slots_available [obj_size_index] += count;
1638                         }
1639
1640                         iter = &block->next;
1641
1642                         /*
1643                          * If there are free slots in the block, add
1644                          * the block to the corresponding free list.
1645                          */
1646                         if (have_free) {
1647                                 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1648                                 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1649                                 block->next_free = free_blocks [index];
1650                                 free_blocks [index] = block;
1651                         }
1652
1653                         update_heap_boundaries_for_block (block);
1654                 } else {
1655                         /*
1656                          * Blocks without live objects are removed from the
1657                          * block list and freed.
1658                          */
1659                         *iter = block->next;
1660
1661 #ifdef FIXED_HEAP
1662                         ms_free_block (block);
1663 #else
1664                         ms_free_block (block->block);
1665
1666                         sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
1667 #endif
1668
1669                         --num_major_sections;
1670                 }
1671         }
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;
1676                         /*
1677                         g_print ("slot size %d - %d of %d used\n",
1678                                         block_obj_sizes [i], slots_used [i], slots_available [i]);
1679                         */
1680                 } else {
1681                         evacuate_block_obj_sizes [i] = FALSE;
1682                 }
1683         }
1684
1685         have_swept = TRUE;
1686 }
1687
1688 static mono_native_thread_return_t
1689 ms_sweep_thread_func (void *dummy)
1690 {
1691         g_assert (concurrent_sweep);
1692
1693         for (;;) {
1694                 int result;
1695
1696                 while ((result = MONO_SEM_WAIT (&ms_sweep_cmd_semaphore)) != 0) {
1697                         if (errno != EINTR)
1698                                 g_error ("MONO_SEM_WAIT FAILED with %d errno %d (%s)", result, errno, strerror (errno));
1699                 }
1700
1701                 ms_sweep ();
1702
1703                 ms_signal_sweep_done ();
1704         }
1705
1706         return NULL;
1707 }
1708
1709 static void
1710 major_sweep (void)
1711 {
1712         if (concurrent_sweep) {
1713                 g_assert (ms_sweep_thread);
1714                 ms_signal_sweep_command ();
1715         } else {
1716                 ms_sweep ();
1717         }
1718 }
1719
1720 static int count_pinned_ref;
1721 static int count_pinned_nonref;
1722 static int count_nonpinned_ref;
1723 static int count_nonpinned_nonref;
1724
1725 static void
1726 count_nonpinned_callback (char *obj, size_t size, void *data)
1727 {
1728         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1729
1730         if (vtable->klass->has_references)
1731                 ++count_nonpinned_ref;
1732         else
1733                 ++count_nonpinned_nonref;
1734 }
1735
1736 static void
1737 count_pinned_callback (char *obj, size_t size, void *data)
1738 {
1739         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1740
1741         if (vtable->klass->has_references)
1742                 ++count_pinned_ref;
1743         else
1744                 ++count_pinned_nonref;
1745 }
1746
1747 static G_GNUC_UNUSED void
1748 count_ref_nonref_objs (void)
1749 {
1750         int total;
1751
1752         count_pinned_ref = 0;
1753         count_pinned_nonref = 0;
1754         count_nonpinned_ref = 0;
1755         count_nonpinned_nonref = 0;
1756
1757         major_iterate_objects (TRUE, FALSE, count_nonpinned_callback, NULL);
1758         major_iterate_objects (FALSE, TRUE, count_pinned_callback, NULL);
1759
1760         total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1761
1762         g_print ("ref: %d pinned %d non-pinned   non-ref: %d pinned %d non-pinned  --  %.1f\n",
1763                         count_pinned_ref, count_nonpinned_ref,
1764                         count_pinned_nonref, count_nonpinned_nonref,
1765                         (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1766 }
1767
1768 static int
1769 ms_calculate_block_obj_sizes (double factor, int *arr)
1770 {
1771         double target_size = sizeof (MonoObject);
1772         int num_sizes = 0;
1773         int last_size = 0;
1774
1775         do {
1776                 int target_count = ceil (MS_BLOCK_FREE / target_size);
1777                 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1778
1779                 if (size != last_size) {
1780                         if (arr)
1781                                 arr [num_sizes] = size;
1782                         ++num_sizes;
1783                         last_size = size;
1784                 }
1785
1786                 target_size *= factor;
1787         } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1788
1789         return num_sizes;
1790 }
1791
1792 /* only valid during minor collections */
1793 static int old_num_major_sections;
1794
1795 static void
1796 major_start_nursery_collection (void)
1797 {
1798         ms_wait_for_sweep_done ();
1799
1800 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1801         consistency_check ();
1802 #endif
1803
1804         old_num_major_sections = num_major_sections;
1805 }
1806
1807 static void
1808 major_finish_nursery_collection (void)
1809 {
1810 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1811         consistency_check ();
1812 #endif
1813         sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1814 }
1815
1816 static void
1817 major_start_major_collection (void)
1818 {
1819         int i;
1820
1821         ms_wait_for_sweep_done ();
1822
1823         /* clear the free lists */
1824         for (i = 0; i < num_block_obj_sizes; ++i) {
1825                 if (!evacuate_block_obj_sizes [i])
1826                         continue;
1827
1828                 free_block_lists [0][i] = NULL;
1829                 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1830         }
1831
1832         // Sweep all unswept blocks
1833         if (lazy_sweep) {
1834                 MSBlockInfo **iter;
1835
1836                 MONO_GC_SWEEP_BEGIN (GENERATION_OLD, TRUE);
1837
1838                 iter = &all_blocks;
1839                 while (*iter) {
1840                         MSBlockInfo *block = *iter;
1841
1842                         sweep_block (block);
1843
1844                         iter = &block->next;
1845                 }
1846
1847                 MONO_GC_SWEEP_END (GENERATION_OLD, TRUE);
1848         }
1849 }
1850
1851 static void
1852 major_finish_major_collection (void)
1853 {
1854 }
1855
1856 static void
1857 major_have_computer_minor_collection_allowance (void)
1858 {
1859 #ifndef FIXED_HEAP
1860         int section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1861
1862         g_assert (have_swept);
1863         ms_wait_for_sweep_done ();
1864         g_assert (!ms_sweep_in_progress);
1865
1866         /*
1867          * FIXME: We don't free blocks on 32 bit platforms because it
1868          * can lead to address space fragmentation, since we're
1869          * allocating blocks in larger contingents.
1870          */
1871         if (sizeof (mword) < 8)
1872                 return;
1873
1874         while (num_empty_blocks > section_reserve) {
1875                 void *next = *(void**)empty_blocks;
1876                 sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP);
1877                 empty_blocks = next;
1878                 /*
1879                  * Needs not be atomic because this is running
1880                  * single-threaded.
1881                  */
1882                 --num_empty_blocks;
1883
1884                 ++stat_major_blocks_freed;
1885         }
1886 #endif
1887 }
1888
1889 static void
1890 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
1891 {
1892         MSBlockInfo *block;
1893
1894         FOREACH_BLOCK (block) {
1895                 block->pin_queue_start = sgen_find_optimized_pin_queue_area (block->block + MS_BLOCK_SKIP, block->block + MS_BLOCK_SIZE,
1896                                 &block->pin_queue_num_entries);
1897         } END_FOREACH_BLOCK;
1898 }
1899
1900 static void
1901 major_pin_objects (SgenGrayQueue *queue)
1902 {
1903         MSBlockInfo *block;
1904
1905         FOREACH_BLOCK (block) {
1906                 mark_pinned_objects_in_block (block, queue);
1907         } END_FOREACH_BLOCK;
1908 }
1909
1910 static void
1911 major_init_to_space (void)
1912 {
1913 }
1914
1915 static void
1916 major_report_pinned_memory_usage (void)
1917 {
1918         g_assert_not_reached ();
1919 }
1920
1921 static gint64
1922 major_get_used_size (void)
1923 {
1924         gint64 size = 0;
1925         MSBlockInfo *block;
1926
1927         FOREACH_BLOCK (block) {
1928                 int count = MS_BLOCK_FREE / block->obj_size;
1929                 void **iter;
1930                 size += count * block->obj_size;
1931                 for (iter = block->free_list; iter; iter = (void**)*iter)
1932                         size -= block->obj_size;
1933         } END_FOREACH_BLOCK;
1934
1935         return size;
1936 }
1937
1938 static int
1939 get_num_major_sections (void)
1940 {
1941         return num_major_sections;
1942 }
1943
1944 static gboolean
1945 major_handle_gc_param (const char *opt)
1946 {
1947 #ifdef FIXED_HEAP
1948         if (g_str_has_prefix (opt, "major-heap-size=")) {
1949                 const char *arg = strchr (opt, '=') + 1;
1950                 glong size;
1951                 if (!mono_gc_parse_environment_string_extract_number (arg, &size))
1952                         return FALSE;
1953                 ms_heap_num_blocks = (size + MS_BLOCK_SIZE - 1) / MS_BLOCK_SIZE;
1954                 g_assert (ms_heap_num_blocks > 0);
1955                 return TRUE;
1956         } else
1957 #endif
1958         if (g_str_has_prefix (opt, "evacuation-threshold=")) {
1959                 const char *arg = strchr (opt, '=') + 1;
1960                 int percentage = atoi (arg);
1961                 if (percentage < 0 || percentage > 100) {
1962                         fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
1963                         exit (1);
1964                 }
1965                 evacuation_threshold = (float)percentage / 100.0;
1966                 return TRUE;
1967         } else if (!strcmp (opt, "concurrent-sweep")) {
1968                 concurrent_sweep = TRUE;
1969                 return TRUE;
1970         } else if (!strcmp (opt, "no-concurrent-sweep")) {
1971                 concurrent_sweep = FALSE;
1972                 return TRUE;
1973         }
1974
1975         return FALSE;
1976 }
1977
1978 static void
1979 major_print_gc_param_usage (void)
1980 {
1981         fprintf (stderr,
1982                         ""
1983 #ifdef FIXED_HEAP
1984                         "  major-heap-size=N (where N is an integer, possibly with a k, m or a g suffix)\n"
1985 #endif
1986                         "  evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
1987                         "  (no-)concurrent-sweep\n"
1988                         );
1989 }
1990
1991 #ifdef SGEN_HAVE_CARDTABLE
1992 static void
1993 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
1994 {
1995         MSBlockInfo *block;
1996
1997         FOREACH_BLOCK (block) {
1998                 if (block->has_references)
1999                         callback ((mword)block->block, MS_BLOCK_SIZE);
2000         } END_FOREACH_BLOCK;
2001 }
2002
2003 #ifdef HEAVY_STATISTICS
2004 extern long long marked_cards;
2005 extern long long scanned_cards;
2006 extern long long scanned_objects;
2007 extern long long remarked_cards;
2008 #endif
2009
2010 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
2011 /*
2012  * MS blocks are 16K aligned.
2013  * Cardtables are 4K aligned, at least.
2014  * This means that the cardtable of a given block is 32 bytes aligned.
2015  */
2016 static guint8*
2017 initial_skip_card (guint8 *card_data)
2018 {
2019         mword *cards = (mword*)card_data;
2020         mword card;
2021         int i;
2022         for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
2023                 card = cards [i];
2024                 if (card)
2025                         break;
2026         }
2027
2028         if (i == CARD_WORDS_PER_BLOCK)
2029                 return card_data + CARDS_PER_BLOCK;
2030
2031 #if defined(__i386__) && defined(__GNUC__)
2032         return card_data + i * 4 +  (__builtin_ffs (card) - 1) / 8;
2033 #elif defined(__x86_64__) && defined(__GNUC__)
2034         return card_data + i * 8 +  (__builtin_ffsll (card) - 1) / 8;
2035 #elif defined(__s390x__) && defined(__GNUC__)
2036         return card_data + i * 8 +  (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
2037 #else
2038         for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
2039                 if (card_data [i])
2040                         return &card_data [i];
2041         }
2042         return card_data;
2043 #endif
2044 }
2045
2046
2047 static G_GNUC_UNUSED guint8*
2048 skip_card (guint8 *card_data, guint8 *card_data_end)
2049 {
2050         while (card_data < card_data_end && !*card_data)
2051                 ++card_data;
2052         return card_data;
2053 }
2054
2055 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
2056 #define MS_BLOCK_OBJ_FAST(b,os,i)                       ((b) + MS_BLOCK_SKIP + (os) * (i))
2057 #define MS_OBJ_ALLOCED_FAST(o,b)                (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
2058
2059 static void
2060 major_scan_card_table (gboolean mod_union, SgenGrayQueue *queue)
2061 {
2062         MSBlockInfo *block;
2063         ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
2064
2065         FOREACH_BLOCK (block) {
2066                 int block_obj_size;
2067                 char *block_start;
2068
2069                 if (!block->has_references)
2070                         continue;
2071
2072                 block_obj_size = block->obj_size;
2073                 block_start = block->block;
2074
2075                 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
2076                         guint8 *cards;
2077 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
2078                         guint8 cards_data [CARDS_PER_BLOCK];
2079 #endif
2080                         char *obj, *end, *base;
2081
2082                         if (mod_union) {
2083 #ifdef SGEN_CONCURRENT_MARK
2084                                 cards = block->cardtable_mod_union;
2085                                 g_assert (cards);
2086 #else
2087                                 g_assert_not_reached ();
2088 #endif
2089                         } else {
2090                         /*We can avoid the extra copy since the remark cardtable was cleaned before */
2091 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
2092                                 cards = sgen_card_table_get_card_scan_address ((mword)block_start);
2093 #else
2094                                 cards = cards_data;
2095                                 if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
2096                                         continue;
2097 #endif
2098                         }
2099
2100                         if (!block->swept)
2101                                 sweep_block (block);
2102
2103                         obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
2104                         end = block_start + MS_BLOCK_SIZE;
2105                         base = sgen_card_table_align_pointer (obj);
2106
2107                         while (obj < end) {
2108                                 int card_offset;
2109
2110                                 if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
2111                                         goto next_large;
2112
2113                                 if (mod_union) {
2114                                         /* FIXME: do this more efficiently */
2115                                         int w, b;
2116                                         MS_CALC_MARK_BIT (w, b, obj);
2117                                         if (!MS_MARK_BIT (block, w, b))
2118                                                 goto next_large;
2119                                 }
2120
2121                                 card_offset = (obj - base) >> CARD_BITS;
2122                                 sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, queue);
2123
2124                         next_large:
2125                                 obj += block_obj_size;
2126                         }
2127                 } else {
2128                         guint8 *card_data, *card_base;
2129                         guint8 *card_data_end;
2130
2131                         /*
2132                          * This is safe in face of card aliasing for the following reason:
2133                          *
2134                          * Major blocks are 16k aligned, or 32 cards aligned.
2135                          * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
2136                          * sizes, they won't overflow the cardtable overlap modulus.
2137                          */
2138                         if (mod_union) {
2139 #ifdef SGEN_CONCURRENT_MARK
2140                                 card_data = card_base = block->cardtable_mod_union;
2141                                 /*
2142                                  * This happens when the nursery
2143                                  * collection that precedes finishing
2144                                  * the concurrent collection allocates
2145                                  * new major blocks.
2146                                  */
2147                                 if (!card_data)
2148                                         continue;
2149 #else
2150                                 g_assert_not_reached ();
2151 #endif
2152                         } else {
2153                                 card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
2154                         }
2155                         card_data_end = card_data + CARDS_PER_BLOCK;
2156
2157                         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)) {
2158                                 int index;
2159                                 int idx = card_data - card_base;
2160                                 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
2161                                 char *end = start + CARD_SIZE_IN_BYTES;
2162                                 char *obj;
2163
2164                                 HEAVY_STAT (++scanned_cards);
2165
2166                                 if (!*card_data)
2167                                         continue;
2168
2169                                 if (!block->swept)
2170                                         sweep_block (block);
2171
2172                                 HEAVY_STAT (++marked_cards);
2173
2174                                 sgen_card_table_prepare_card_for_scanning (card_data);
2175
2176                                 if (idx == 0)
2177                                         index = 0;
2178                                 else
2179                                         index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
2180
2181                                 obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
2182                                 while (obj < end) {
2183                                         if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
2184                                                 goto next_small;
2185
2186                                         if (mod_union) {
2187                                                 /* FIXME: do this more efficiently */
2188                                                 int w, b;
2189                                                 MS_CALC_MARK_BIT (w, b, obj);
2190                                                 if (!MS_MARK_BIT (block, w, b))
2191                                                         goto next_small;
2192                                         }
2193
2194                                         HEAVY_STAT (++scanned_objects);
2195                                         scan_func (obj, queue);
2196                                 next_small:
2197                                         obj += block_obj_size;
2198                                 }
2199                                 HEAVY_STAT (if (*card_data) ++remarked_cards);
2200                         }
2201                 }
2202         } END_FOREACH_BLOCK;
2203 }
2204
2205 #ifdef SGEN_CONCURRENT_MARK
2206 static void
2207 update_cardtable_mod_union (void)
2208 {
2209         MSBlockInfo *block;
2210
2211         FOREACH_BLOCK (block) {
2212                 guint8 *cards;
2213                 gboolean init = FALSE;
2214
2215                 if (!block->cardtable_mod_union) {
2216                         block->cardtable_mod_union = sgen_alloc_internal_dynamic (CARDS_PER_BLOCK,
2217                                         INTERNAL_MEM_CARDTABLE_MOD_UNION, TRUE);
2218                         init = TRUE;
2219                 }
2220
2221                 cards = sgen_card_table_get_card_scan_address ((mword)block->block);
2222                 if (init) {
2223                         memcpy (block->cardtable_mod_union, cards, CARDS_PER_BLOCK);
2224                 } else {
2225                         int i;
2226                         for (i = 0; i < CARDS_PER_BLOCK; ++i)
2227                                 block->cardtable_mod_union [i] |= cards [i];
2228                 }
2229         } END_FOREACH_BLOCK;
2230 }
2231 #endif
2232 #endif
2233
2234 static gboolean
2235 major_is_worker_thread (MonoNativeThreadId thread)
2236 {
2237         if (concurrent_sweep)
2238                 return thread == ms_sweep_thread;
2239         else
2240                 return FALSE;
2241 }
2242
2243 static void
2244 alloc_free_block_lists (MSBlockInfo ***lists)
2245 {
2246         int i;
2247         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
2248                 lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2249 }
2250
2251 #ifdef SGEN_PARALLEL_MARK
2252 static void*
2253 major_alloc_worker_data (void)
2254 {
2255         /* FIXME: free this when the workers come down */
2256         MSBlockInfo ***lists = malloc (sizeof (MSBlockInfo**) * MS_BLOCK_TYPE_MAX);
2257         alloc_free_block_lists (lists);
2258         return lists;
2259 }
2260
2261 static void
2262 major_init_worker_thread (void *data)
2263 {
2264         MSBlockInfo ***lists = data;
2265         int i;
2266
2267         g_assert (lists && lists != free_block_lists);
2268         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
2269                 int j;
2270                 for (j = 0; j < num_block_obj_sizes; ++j)
2271                         g_assert (!lists [i][j]);
2272         }
2273
2274 #ifdef HAVE_KW_THREAD
2275         workers_free_block_lists = data;
2276 #else
2277         mono_native_tls_set_value (workers_free_block_lists_key, data);
2278 #endif
2279 }
2280
2281 static void
2282 major_reset_worker_data (void *data)
2283 {
2284         MSBlockInfo ***lists = data;
2285         int i;
2286         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
2287                 int j;
2288                 for (j = 0; j < num_block_obj_sizes; ++j)
2289                         lists [i][j] = NULL;
2290         }
2291 }
2292 #endif
2293
2294 #undef pthread_create
2295
2296 static void
2297 post_param_init (SgenMajorCollector *collector)
2298 {
2299         if (concurrent_sweep) {
2300                 if (!mono_native_thread_create (&ms_sweep_thread, ms_sweep_thread_func, NULL)) {
2301                         fprintf (stderr, "Error: Could not create sweep thread.\n");
2302                         exit (1);
2303                 }
2304         }
2305
2306         collector->sweeps_lazily = lazy_sweep;
2307 }
2308
2309 void
2310 #ifdef SGEN_CONCURRENT_MARK
2311 sgen_marksweep_conc_init
2312 #else
2313 #ifdef SGEN_PARALLEL_MARK
2314 #ifdef FIXED_HEAP
2315 sgen_marksweep_fixed_par_init
2316 #else
2317 sgen_marksweep_par_init
2318 #endif
2319 #else
2320 #ifdef FIXED_HEAP
2321 sgen_marksweep_fixed_init
2322 #else
2323 sgen_marksweep_init
2324 #endif
2325 #endif
2326 #endif
2327         (SgenMajorCollector *collector)
2328 {
2329         int i;
2330
2331 #ifndef FIXED_HEAP
2332         sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
2333 #endif
2334
2335         num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
2336         block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2337         ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
2338
2339         evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2340         for (i = 0; i < num_block_obj_sizes; ++i)
2341                 evacuate_block_obj_sizes [i] = FALSE;
2342
2343         /*
2344         {
2345                 int i;
2346                 g_print ("block object sizes:\n");
2347                 for (i = 0; i < num_block_obj_sizes; ++i)
2348                         g_print ("%d\n", block_obj_sizes [i]);
2349         }
2350         */
2351
2352         alloc_free_block_lists (free_block_lists);
2353
2354         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
2355                 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
2356         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
2357                 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
2358
2359 #ifdef SGEN_PARALLEL_MARK
2360         LOCK_INIT (ms_block_list_mutex);
2361 #endif
2362
2363         mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
2364         mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
2365         mono_counters_register ("# major blocks lazy swept", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_lazy_swept);
2366         mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
2367         mono_counters_register ("Wait for sweep time", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &stat_time_wait_for_sweep);
2368 #ifdef SGEN_PARALLEL_MARK
2369 #ifndef HAVE_KW_THREAD
2370         mono_native_tls_alloc (&workers_free_block_lists_key, NULL);
2371 #endif
2372 #endif
2373
2374         /*
2375          * FIXME: These are superfluous if concurrent sweep is
2376          * disabled.  We might want to create them lazily.
2377          */
2378         MONO_SEM_INIT (&ms_sweep_cmd_semaphore, 0);
2379         MONO_SEM_INIT (&ms_sweep_done_semaphore, 0);
2380
2381         collector->section_size = MAJOR_SECTION_SIZE;
2382 #ifdef SGEN_PARALLEL_MARK
2383         collector->is_parallel = TRUE;
2384         collector->alloc_worker_data = major_alloc_worker_data;
2385         collector->init_worker_thread = major_init_worker_thread;
2386         collector->reset_worker_data = major_reset_worker_data;
2387 #else
2388         collector->is_parallel = FALSE;
2389 #endif
2390 #ifdef SGEN_CONCURRENT_MARK
2391         collector->is_concurrent = TRUE;
2392 #else
2393         collector->is_concurrent = FALSE;
2394 #endif
2395         collector->supports_cardtable = TRUE;
2396
2397         collector->have_swept = &have_swept;
2398
2399         collector->alloc_heap = major_alloc_heap;
2400         collector->is_object_live = major_is_object_live;
2401         collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2402         collector->alloc_degraded = major_alloc_degraded;
2403
2404         collector->alloc_object = major_alloc_object;
2405 #ifdef SGEN_PARALLEL_MARK
2406         collector->par_alloc_object = major_par_alloc_object;
2407 #endif
2408         collector->free_pinned_object = free_pinned_object;
2409         collector->iterate_objects = major_iterate_objects;
2410         collector->free_non_pinned_object = major_free_non_pinned_object;
2411         collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2412         collector->pin_objects = major_pin_objects;
2413         collector->pin_major_object = pin_major_object;
2414 #ifdef SGEN_HAVE_CARDTABLE
2415         collector->scan_card_table = major_scan_card_table;
2416         collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2417 #ifdef SGEN_CONCURRENT_MARK
2418         collector->update_cardtable_mod_union = update_cardtable_mod_union;
2419 #endif
2420 #endif
2421         collector->init_to_space = major_init_to_space;
2422         collector->sweep = major_sweep;
2423         collector->check_scan_starts = major_check_scan_starts;
2424         collector->dump_heap = major_dump_heap;
2425         collector->get_used_size = major_get_used_size;
2426         collector->start_nursery_collection = major_start_nursery_collection;
2427         collector->finish_nursery_collection = major_finish_nursery_collection;
2428         collector->start_major_collection = major_start_major_collection;
2429         collector->finish_major_collection = major_finish_major_collection;
2430         collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2431         collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2432         collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2433         collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2434         collector->get_num_major_sections = get_num_major_sections;
2435         collector->handle_gc_param = major_handle_gc_param;
2436         collector->print_gc_param_usage = major_print_gc_param_usage;
2437         collector->is_worker_thread = major_is_worker_thread;
2438         collector->post_param_init = post_param_init;
2439         collector->is_valid_object = major_is_valid_object;
2440         collector->describe_pointer = major_describe_pointer;
2441
2442         collector->major_ops.copy_or_mark_object = major_copy_or_mark_object;
2443         collector->major_ops.scan_object = major_scan_object;
2444 #ifdef SGEN_CONCURRENT_MARK
2445         collector->major_ops.scan_vtype = major_scan_vtype;
2446 #endif
2447
2448 #ifdef SGEN_HAVE_CARDTABLE
2449         /*cardtable requires major pages to be 8 cards aligned*/
2450         g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);
2451 #endif
2452 }
2453
2454 #endif