mono/metadata/sgen-marksweep.c

   1 /*
   2  * sgen-marksweep.c: Simple generational GC.
   3  *
   4  * Author:
   5  *      Mark Probst <mark.probst@gmail.com>
   6  *
   7  * Copyright 2009-2010 Novell, Inc.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining
  10  * a copy of this software and associated documentation files (the
  11  * "Software"), to deal in the Software without restriction, including
  12  * without limitation the rights to use, copy, modify, merge, publish,
  13  * distribute, sublicense, and/or sell copies of the Software, and to
  14  * permit persons to whom the Software is furnished to do so, subject to
  15  * the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be
  18  * included in all copies or substantial portions of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27  */
  28
  29 #include "config.h"
  30
  31 #ifdef HAVE_SGEN_GC
  32
  33 #include <math.h>
  34 #include <errno.h>
  35
  36 #include "utils/mono-counters.h"
  37 #include "utils/mono-semaphore.h"
  38 #include "utils/mono-time.h"
  39 #include "metadata/object-internals.h"
  40 #include "metadata/profiler-private.h"
  41
  42 #include "metadata/sgen-gc.h"
  43 #include "metadata/sgen-protocol.h"
  44 #include "metadata/sgen-cardtable.h"
  45 #include "metadata/gc-internal.h"
  46
  47 #define MS_BLOCK_SIZE   (16*1024)
  48 #define MS_BLOCK_SIZE_SHIFT     14
  49 #define MAJOR_SECTION_SIZE      MS_BLOCK_SIZE
  50 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
  51
  52 #ifdef FIXED_HEAP
  53 #define MS_DEFAULT_HEAP_NUM_BLOCKS      (32 * 1024) /* 512 MB */
  54 #endif
  55
  56 /*
  57  * Don't allocate single blocks, but alloc a contingent of this many
  58  * blocks in one swoop.
  59  */
  60 #define MS_BLOCK_ALLOC_NUM      32
  61
  62 /*
  63  * Number of bytes before the first object in a block.  At the start
  64  * of a block is the MSBlockHeader, then opional padding, then come
  65  * the objects, so this must be >= sizeof (MSBlockHeader).
  66  */
  67 #ifdef FIXED_HEAP
  68 #define MS_BLOCK_SKIP   0
  69 #else
  70 #define MS_BLOCK_SKIP   16
  71 #endif
  72
  73 #define MS_BLOCK_FREE   (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
  74
  75 #define MS_NUM_MARK_WORDS       ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
  76
  77 #if SGEN_MAX_SMALL_OBJ_SIZE > MS_BLOCK_FREE / 2
  78 #error MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2
  79 #endif
  80
  81 typedef struct _MSBlockInfo MSBlockInfo;
  82 struct _MSBlockInfo {
  83         int obj_size;
  84         int obj_size_index;
  85         int pin_queue_num_entries;
  86         unsigned int pinned : 1;
  87         unsigned int has_references : 1;
  88         unsigned int has_pinned : 1;    /* means cannot evacuate */
  89         unsigned int is_to_space : 1;
  90 #ifdef FIXED_HEAP
  91         unsigned int used : 1;
  92         unsigned int zeroed : 1;
  93 #endif
  94         MSBlockInfo *next;
  95         char *block;
  96         void **free_list;
  97         MSBlockInfo *next_free;
  98         void **pin_queue_start;
  99         mword mark_words [MS_NUM_MARK_WORDS];
 100 };
 101
 102 #ifdef FIXED_HEAP
 103 static int 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_DATA_FOR_OBJ(o)        ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
 116
 117 #ifdef FIXED_HEAP
 118 #define MS_BLOCK_FOR_OBJ(o)             (&block_infos [(mword)((char*)(o) - ms_heap_start) >> MS_BLOCK_SIZE_SHIFT])
 119 #else
 120 typedef struct {
 121         MSBlockInfo *info;
 122 } MSBlockHeader;
 123
 124 #define MS_BLOCK_FOR_OBJ(o)             (((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
 125 #endif
 126
 127 #define MS_BLOCK_OBJ_INDEX(o,b) (((char*)(o) - ((b)->block + MS_BLOCK_SKIP)) / (b)->obj_size)
 128
 129 #define MS_CALC_MARK_BIT(w,b,o)         do {                            \
 130                 int i = ((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o))) >> SGEN_ALLOC_ALIGN_BITS; \
 131                 if (sizeof (mword) == 4) {                              \
 132                         (w) = i >> 5;                                   \
 133                         (b) = i & 31;                                   \
 134                 } else {                                                \
 135                         (w) = i >> 6;                                   \
 136                         (b) = i & 63;                                   \
 137                 }                                                       \
 138         } while (0)
 139
 140 #define MS_MARK_BIT(bl,w,b)     ((bl)->mark_words [(w)] & (1L << (b)))
 141 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (1L << (b)))
 142 #define MS_PAR_SET_MARK_BIT(was_marked,bl,w,b)  do {                    \
 143                 mword __old = (bl)->mark_words [(w)];                   \
 144                 mword __bitmask = 1L << (b);                            \
 145                 if (__old & __bitmask) {                                \
 146                         was_marked = TRUE;                              \
 147                         break;                                          \
 148                 }                                                       \
 149                 if (SGEN_CAS_PTR ((gpointer*)&(bl)->mark_words [(w)],   \
 150                                                 (gpointer)(__old | __bitmask), \
 151                                                 (gpointer)__old) ==     \
 152                                 (gpointer)__old) {                      \
 153                         was_marked = FALSE;                             \
 154                         break;                                          \
 155                 }                                                       \
 156         } while (1)
 157
 158 #define MS_OBJ_ALLOCED(o,b)     (*(void**)(o) && (*(char**)(o) < (b)->block || *(char**)(o) >= (b)->block + MS_BLOCK_SIZE))
 159
 160 #define MS_BLOCK_OBJ_SIZE_FACTOR        (sqrt (2.0))
 161
 162 /*
 163  * This way we can lookup block object size indexes for sizes up to
 164  * 256 bytes with a single load.
 165  */
 166 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES      32
 167
 168 static int *block_obj_sizes;
 169 static int num_block_obj_sizes;
 170 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
 171
 172 #define MS_BLOCK_FLAG_PINNED    1
 173 #define MS_BLOCK_FLAG_REFS      2
 174
 175 #define MS_BLOCK_TYPE_MAX       4
 176
 177 #ifdef SGEN_PARALLEL_MARK
 178 static LOCK_DECLARE (ms_block_list_mutex);
 179 #define LOCK_MS_BLOCK_LIST mono_mutex_lock (&ms_block_list_mutex)
 180 #define UNLOCK_MS_BLOCK_LIST mono_mutex_unlock (&ms_block_list_mutex)
 181 #endif
 182
 183 static gboolean *evacuate_block_obj_sizes;
 184 static float evacuation_threshold = 0.666;
 185
 186 static gboolean concurrent_sweep = FALSE;
 187 static gboolean have_swept;
 188
 189 /* all allocated blocks in the system */
 190 static MSBlockInfo *all_blocks;
 191
 192 #ifdef FIXED_HEAP
 193 /* non-allocated block free-list */
 194 static MSBlockInfo *empty_blocks = NULL;
 195 #else
 196 /* non-allocated block free-list */
 197 static void *empty_blocks = NULL;
 198 static int num_empty_blocks = 0;
 199 #endif
 200
 201 #define FOREACH_BLOCK(bl)       for ((bl) = all_blocks; (bl); (bl) = (bl)->next) {
 202 #define END_FOREACH_BLOCK       }
 203
 204 static int num_major_sections = 0;
 205 /* one free block list for each block object size */
 206 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
 207
 208 #ifdef SGEN_PARALLEL_MARK
 209 #ifdef HAVE_KW_THREAD
 210 static __thread MSBlockInfo ***workers_free_block_lists;
 211 #else
 212 static MonoNativeTlsKey workers_free_block_lists_key;
 213 #endif
 214 #endif
 215
 216 static long long stat_major_blocks_alloced = 0;
 217 static long long stat_major_blocks_freed = 0;
 218 static long long stat_major_objects_evacuated = 0;
 219 static long long stat_time_wait_for_sweep = 0;
 220
 221 static gboolean ms_sweep_in_progress = FALSE;
 222 static MonoNativeThreadId ms_sweep_thread;
 223 static MonoSemType ms_sweep_cmd_semaphore;
 224 static MonoSemType ms_sweep_done_semaphore;
 225
 226 static void
 227 ms_signal_sweep_command (void)
 228 {
 229         if (!concurrent_sweep)
 230                 return;
 231
 232         g_assert (!ms_sweep_in_progress);
 233         ms_sweep_in_progress = TRUE;
 234         MONO_SEM_POST (&ms_sweep_cmd_semaphore);
 235 }
 236
 237 static void
 238 ms_signal_sweep_done (void)
 239 {
 240         if (!concurrent_sweep)
 241                 return;
 242
 243         MONO_SEM_POST (&ms_sweep_done_semaphore);
 244 }
 245
 246 static void
 247 ms_wait_for_sweep_done (void)
 248 {
 249         SGEN_TV_DECLARE (atv);
 250         SGEN_TV_DECLARE (btv);
 251         int result;
 252
 253         if (!concurrent_sweep)
 254                 return;
 255
 256         if (!ms_sweep_in_progress)
 257                 return;
 258
 259         SGEN_TV_GETTIME (atv);
 260         while ((result = MONO_SEM_WAIT (&ms_sweep_done_semaphore)) != 0) {
 261                 if (errno != EINTR)
 262                         g_error ("MONO_SEM_WAIT");
 263         }
 264         SGEN_TV_GETTIME (btv);
 265         stat_time_wait_for_sweep += SGEN_TV_ELAPSED (atv, btv);
 266
 267         g_assert (ms_sweep_in_progress);
 268         ms_sweep_in_progress = FALSE;
 269 }
 270
 271 static int
 272 ms_find_block_obj_size_index (int size)
 273 {
 274         int i;
 275         DEBUG (9, g_assert (size <= SGEN_MAX_SMALL_OBJ_SIZE));
 276         for (i = 0; i < num_block_obj_sizes; ++i)
 277                 if (block_obj_sizes [i] >= size)
 278                         return i;
 279         g_error ("no object of size %d\n", size);
 280 }
 281
 282 #define FREE_BLOCKS_FROM(lists,p,r)     (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
 283 #define FREE_BLOCKS(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 284 #ifdef SGEN_PARALLEL_MARK
 285 #ifdef HAVE_KW_THREAD
 286 #define FREE_BLOCKS_LOCAL(p,r)          (FREE_BLOCKS_FROM (workers_free_block_lists, (p), (r)))
 287 #else
 288 #define FREE_BLOCKS_LOCAL(p,r)          (FREE_BLOCKS_FROM (((MSBlockInfo***)(mono_native_tls_get_value (workers_free_block_lists_key))), (p), (r)))
 289 #endif
 290 #else
 291 //#define FREE_BLOCKS_LOCAL(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 292 #endif
 293
 294 #define MS_BLOCK_OBJ_SIZE_INDEX(s)                              \
 295         (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ?      \
 296          fast_block_obj_size_indexes [((s)+7)>>3] :             \
 297          ms_find_block_obj_size_index ((s)))
 298
 299 #ifdef FIXED_HEAP
 300 static void*
 301 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 302 {
 303         char *nursery_start;
 304         mword major_heap_size = ms_heap_num_blocks * MS_BLOCK_SIZE;
 305         mword alloc_size = nursery_size + major_heap_size;
 306         int i;
 307
 308         g_assert (ms_heap_num_blocks > 0);
 309         g_assert (nursery_size % MS_BLOCK_SIZE == 0);
 310         if (nursery_align)
 311                 g_assert (nursery_align % MS_BLOCK_SIZE == 0);
 312
 313         nursery_start = sgen_alloc_os_memory_aligned (alloc_size, nursery_align ? nursery_align : MS_BLOCK_SIZE, TRUE);
 314         ms_heap_start = nursery_start + nursery_size;
 315         ms_heap_end = ms_heap_start + major_heap_size;
 316
 317         block_infos = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo) * ms_heap_num_blocks, INTERNAL_MEM_MS_BLOCK_INFO);
 318
 319         for (i = 0; i < ms_heap_num_blocks; ++i) {
 320                 block_infos [i].block = ms_heap_start + i * MS_BLOCK_SIZE;
 321                 if (i < ms_heap_num_blocks - 1)
 322                         block_infos [i].next_free = &block_infos [i + 1];
 323                 else
 324                         block_infos [i].next_free = NULL;
 325                 block_infos [i].zeroed = TRUE;
 326         }
 327
 328         empty_blocks = &block_infos [0];
 329
 330         return nursery_start;
 331 }
 332 #else
 333 static void*
 334 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 335 {
 336         char *start;
 337         if (nursery_align)
 338                 start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, TRUE);
 339         else
 340                 start = sgen_alloc_os_memory (nursery_size, TRUE);
 341
 342         return start;
 343 }
 344 #endif
 345
 346 static void
 347 update_heap_boundaries_for_block (MSBlockInfo *block)
 348 {
 349         sgen_update_heap_boundaries ((mword)block->block, (mword)block->block + MS_BLOCK_SIZE);
 350 }
 351
 352 #ifdef FIXED_HEAP
 353 static MSBlockInfo*
 354 ms_get_empty_block (void)
 355 {
 356         MSBlockInfo *block;
 357
 358         g_assert (empty_blocks);
 359
 360         do {
 361                 block = empty_blocks;
 362         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block->next_free, block) != block);
 363
 364         block->used = TRUE;
 365
 366         if (!block->zeroed)
 367                 memset (block->block, 0, MS_BLOCK_SIZE);
 368
 369         return block;
 370 }
 371
 372 static void
 373 ms_free_block (MSBlockInfo *block)
 374 {
 375         block->next_free = empty_blocks;
 376         empty_blocks = block;
 377         block->used = FALSE;
 378         block->zeroed = FALSE;
 379         sgen_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 380 }
 381 #else
 382 static void*
 383 ms_get_empty_block (void)
 384 {
 385         char *p;
 386         int i;
 387         void *block, *empty, *next;
 388
 389  retry:
 390         if (!empty_blocks) {
 391                 p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * MS_BLOCK_ALLOC_NUM, MS_BLOCK_SIZE, TRUE);
 392
 393                 for (i = 0; i < MS_BLOCK_ALLOC_NUM; ++i) {
 394                         block = p;
 395                         /*
 396                          * We do the free list update one after the
 397                          * other so that other threads can use the new
 398                          * blocks as quickly as possible.
 399                          */
 400                         do {
 401                                 empty = empty_blocks;
 402                                 *(void**)block = empty;
 403                         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
 404                         p += MS_BLOCK_SIZE;
 405                 }
 406
 407                 SGEN_ATOMIC_ADD (num_empty_blocks, MS_BLOCK_ALLOC_NUM);
 408
 409                 stat_major_blocks_alloced += MS_BLOCK_ALLOC_NUM;
 410         }
 411
 412         do {
 413                 empty = empty_blocks;
 414                 if (!empty)
 415                         goto retry;
 416                 block = empty;
 417                 next = *(void**)block;
 418         } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
 419
 420         SGEN_ATOMIC_ADD (num_empty_blocks, -1);
 421
 422         *(void**)block = NULL;
 423
 424         g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
 425
 426         return block;
 427 }
 428
 429 static void
 430 ms_free_block (void *block)
 431 {
 432         void *empty;
 433
 434         sgen_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 435         memset (block, 0, MS_BLOCK_SIZE);
 436
 437         do {
 438                 empty = empty_blocks;
 439                 *(void**)block = empty;
 440         } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
 441
 442         SGEN_ATOMIC_ADD (num_empty_blocks, 1);
 443 }
 444 #endif
 445
 446 //#define MARKSWEEP_CONSISTENCY_CHECK
 447
 448 #ifdef MARKSWEEP_CONSISTENCY_CHECK
 449 static void
 450 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
 451 {
 452         MSBlockInfo *b;
 453
 454         for (; block; block = block->next_free) {
 455                 g_assert (block->obj_size == size);
 456                 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
 457
 458                 /* blocks in the free lists must have at least
 459                    one free slot */
 460                 g_assert (block->free_list);
 461
 462 #ifdef FIXED_HEAP
 463                 /* the block must not be in the empty_blocks list */
 464                 for (b = empty_blocks; b; b = b->next_free)
 465                         g_assert (b != block);
 466 #endif
 467                 /* the block must be in the all_blocks list */
 468                 for (b = all_blocks; b; b = b->next) {
 469                         if (b == block)
 470                                 break;
 471                 }
 472                 g_assert (b == block);
 473         }
 474 }
 475
 476 static void
 477 check_empty_blocks (void)
 478 {
 479 #ifndef FIXED_HEAP
 480         void *p;
 481         int i = 0;
 482         for (p = empty_blocks; p; p = *(void**)p)
 483                 ++i;
 484         g_assert (i == num_empty_blocks);
 485 #endif
 486 }
 487
 488 static void
 489 consistency_check (void)
 490 {
 491         MSBlockInfo *block;
 492         int i;
 493
 494         /* check all blocks */
 495         FOREACH_BLOCK (block) {
 496                 int count = MS_BLOCK_FREE / block->obj_size;
 497                 int num_free = 0;
 498                 void **free;
 499
 500 #ifndef FIXED_HEAP
 501                 /* check block header */
 502                 g_assert (((MSBlockHeader*)block->block)->info == block);
 503 #endif
 504
 505                 /* count number of free slots */
 506                 for (i = 0; i < count; ++i) {
 507                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 508                         if (!MS_OBJ_ALLOCED (obj, block))
 509                                 ++num_free;
 510                 }
 511
 512                 /* check free list */
 513                 for (free = block->free_list; free; free = (void**)*free) {
 514                         g_assert (MS_BLOCK_FOR_OBJ (free) == block);
 515                         --num_free;
 516                 }
 517                 g_assert (num_free == 0);
 518
 519                 /* check all mark words are zero */
 520                 for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
 521                         g_assert (block->mark_words [i] == 0);
 522         } END_FOREACH_BLOCK;
 523
 524         /* check free blocks */
 525         for (i = 0; i < num_block_obj_sizes; ++i) {
 526                 int j;
 527                 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
 528                         check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
 529         }
 530
 531         check_empty_blocks ();
 532 }
 533 #endif
 534
 535 static gboolean
 536 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
 537 {
 538         int size = block_obj_sizes [size_index];
 539         int count = MS_BLOCK_FREE / size;
 540         MSBlockInfo *info;
 541 #ifdef SGEN_PARALLEL_MARK
 542         MSBlockInfo *next;
 543 #endif
 544 #ifndef FIXED_HEAP
 545         MSBlockHeader *header;
 546 #endif
 547         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 548         char *obj_start;
 549         int i;
 550
 551         if (!sgen_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
 552                 return FALSE;
 553
 554 #ifdef FIXED_HEAP
 555         info = ms_get_empty_block ();
 556 #else
 557         info = sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
 558 #endif
 559
 560         DEBUG (9, g_assert (count >= 2));
 561
 562         info->obj_size = size;
 563         info->obj_size_index = size_index;
 564         info->pinned = pinned;
 565         info->has_references = has_references;
 566         info->has_pinned = pinned;
 567         info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD); /*FIXME WHY??? */
 568 #ifndef FIXED_HEAP
 569         info->block = ms_get_empty_block ();
 570
 571         header = (MSBlockHeader*) info->block;
 572         header->info = info;
 573 #endif
 574
 575         update_heap_boundaries_for_block (info);
 576
 577         /* build free list */
 578         obj_start = info->block + MS_BLOCK_SKIP;
 579         info->free_list = (void**)obj_start;
 580         /* we're skipping the last one - it must be nulled */
 581         for (i = 0; i < count - 1; ++i) {
 582                 char *next_obj_start = obj_start + size;
 583                 *(void**)obj_start = next_obj_start;
 584                 obj_start = next_obj_start;
 585         }
 586         /* the last one */
 587         *(void**)obj_start = NULL;
 588
 589 #ifdef SGEN_PARALLEL_MARK
 590         do {
 591                 next = info->next_free = free_blocks [size_index];
 592         } while (SGEN_CAS_PTR ((void**)&free_blocks [size_index], info, next) != next);
 593
 594         do {
 595                 next = info->next = all_blocks;
 596         } while (SGEN_CAS_PTR ((void**)&all_blocks, info, next) != next);
 597 #else
 598         info->next_free = free_blocks [size_index];
 599         free_blocks [size_index] = info;
 600
 601         info->next = all_blocks;
 602         all_blocks = info;
 603 #endif
 604
 605         ++num_major_sections;
 606         return TRUE;
 607 }
 608
 609 static gboolean
 610 obj_is_from_pinned_alloc (char *ptr)
 611 {
 612         MSBlockInfo *block;
 613
 614         FOREACH_BLOCK (block) {
 615                 if (ptr >= block->block && ptr <= block->block + MS_BLOCK_SIZE)
 616                         return block->pinned;
 617         } END_FOREACH_BLOCK;
 618         return FALSE;
 619 }
 620
 621 static void*
 622 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
 623 {
 624         MSBlockInfo *block;
 625         void *obj;
 626
 627         block = free_blocks [size_index];
 628         DEBUG (9, g_assert (block));
 629
 630         obj = block->free_list;
 631         DEBUG (9, g_assert (obj));
 632
 633         block->free_list = *(void**)obj;
 634         if (!block->free_list) {
 635                 free_blocks [size_index] = block->next_free;
 636                 block->next_free = NULL;
 637         }
 638
 639         return obj;
 640 }
 641
 642 #ifdef SGEN_PARALLEL_MARK
 643 static gboolean
 644 try_remove_block_from_free_list (MSBlockInfo *block, MSBlockInfo **free_blocks, int size_index)
 645 {
 646         /*
 647          * No more free slots in the block, so try to free the block.
 648          * Don't try again if we don't succeed - another thread will
 649          * already have done it.
 650          */
 651         MSBlockInfo *next_block = block->next_free;
 652         if (SGEN_CAS_PTR ((void**)&free_blocks [size_index], next_block, block) == block) {
 653                 /*
 654                 void *old = SGEN_CAS_PTR ((void**)&block->next_free, NULL, next_block);
 655                 g_assert (old == next_block);
 656                 */
 657                 block->next_free = NULL;
 658                 return TRUE;
 659         }
 660         return FALSE;
 661 }
 662
 663 static void*
 664 alloc_obj_par (int size, gboolean pinned, gboolean has_references)
 665 {
 666         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 667         MSBlockInfo **free_blocks_local = FREE_BLOCKS_LOCAL (pinned, has_references);
 668         MSBlockInfo *block;
 669         void *obj;
 670
 671         DEBUG (9, g_assert (!ms_sweep_in_progress));
 672         DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
 673
 674         if (free_blocks_local [size_index]) {
 675         get_slot:
 676                 obj = unlink_slot_from_free_list_uncontested (free_blocks_local, size_index);
 677         } else {
 678                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 679
 680         get_block:
 681                 block = free_blocks [size_index];
 682                 if (block) {
 683                         if (!try_remove_block_from_free_list (block, free_blocks, size_index))
 684                                 goto get_block;
 685
 686                         g_assert (block->next_free == NULL);
 687                         g_assert (block->free_list);
 688                         block->next_free = free_blocks_local [size_index];
 689                         free_blocks_local [size_index] = block;
 690
 691                         goto get_slot;
 692                 } else {
 693                         gboolean success;
 694
 695                         LOCK_MS_BLOCK_LIST;
 696                         success = ms_alloc_block (size_index, pinned, has_references);
 697                         UNLOCK_MS_BLOCK_LIST;
 698
 699                         if (G_UNLIKELY (!success))
 700                                 return NULL;
 701
 702                         goto get_block;
 703                 }
 704         }
 705
 706         /*
 707          * FIXME: This should not be necessary because it'll be
 708          * overwritten by the vtable immediately.
 709          */
 710         *(void**)obj = NULL;
 711
 712         return obj;
 713 }
 714
 715 static void*
 716 major_par_alloc_object (int size, gboolean has_references)
 717 {
 718         return alloc_obj_par (size, FALSE, has_references);
 719 }
 720 #endif
 721
 722 static void*
 723 alloc_obj (int size, gboolean pinned, gboolean has_references)
 724 {
 725         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 726         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 727         void *obj;
 728
 729 #ifdef SGEN_PARALLEL_MARK
 730         DEBUG (9, g_assert (current_collection_generation != GENERATION_OLD));
 731 #endif
 732
 733         DEBUG (9, g_assert (!ms_sweep_in_progress));
 734
 735         if (!free_blocks [size_index]) {
 736                 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
 737                         return NULL;
 738         }
 739
 740         obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
 741
 742         /*
 743          * FIXME: This should not be necessary because it'll be
 744          * overwritten by the vtable immediately.
 745          */
 746         *(void**)obj = NULL;
 747
 748         return obj;
 749 }
 750
 751 static void*
 752 major_alloc_object (int size, gboolean has_references)
 753 {
 754         return alloc_obj (size, FALSE, has_references);
 755 }
 756
 757 /*
 758  * We're not freeing the block if it's empty.  We leave that work for
 759  * the next major collection.
 760  *
 761  * This is just called from the domain clearing code, which runs in a
 762  * single thread and has the GC lock, so we don't need an extra lock.
 763  */
 764 static void
 765 free_object (char *obj, size_t size, gboolean pinned)
 766 {
 767         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 768         int word, bit;
 769         DEBUG (9, g_assert ((pinned && block->pinned) || (!pinned && !block->pinned)));
 770         DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
 771         MS_CALC_MARK_BIT (word, bit, obj);
 772         DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
 773         if (!block->free_list) {
 774                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
 775                 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 776                 DEBUG (9, g_assert (!block->next_free));
 777                 block->next_free = free_blocks [size_index];
 778                 free_blocks [size_index] = block;
 779         }
 780         memset (obj, 0, size);
 781         *(void**)obj = block->free_list;
 782         block->free_list = (void**)obj;
 783 }
 784
 785 static void
 786 major_free_non_pinned_object (char *obj, size_t size)
 787 {
 788         free_object (obj, size, FALSE);
 789 }
 790
 791 /* size is a multiple of SGEN_ALLOC_ALIGN */
 792 static void*
 793 major_alloc_small_pinned_obj (size_t size, gboolean has_references)
 794 {
 795         void *res;
 796
 797         ms_wait_for_sweep_done ();
 798
 799         res = alloc_obj (size, TRUE, has_references);
 800          /*If we failed to alloc memory, we better try releasing memory
 801           *as pinned alloc is requested by the runtime.
 802           */
 803          if (!res) {
 804                  sgen_collect_major_no_lock ("pinned alloc failure");
 805                  res = alloc_obj (size, TRUE, has_references);
 806          }
 807          return res;
 808 }
 809
 810 static void
 811 free_pinned_object (char *obj, size_t size)
 812 {
 813         free_object (obj, size, TRUE);
 814 }
 815
 816 /*
 817  * size is already rounded up and we hold the GC lock.
 818  */
 819 static void*
 820 major_alloc_degraded (MonoVTable *vtable, size_t size)
 821 {
 822         void *obj;
 823         int old_num_sections;
 824
 825         ms_wait_for_sweep_done ();
 826
 827         old_num_sections = num_major_sections;
 828
 829         obj = alloc_obj (size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
 830         if (G_LIKELY (obj)) {
 831                 *(MonoVTable**)obj = vtable;
 832                 HEAVY_STAT (++stat_objects_alloced_degraded);
 833                 HEAVY_STAT (stat_bytes_alloced_degraded += size);
 834                 g_assert (num_major_sections >= old_num_sections);
 835                 sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
 836         }
 837         return obj;
 838 }
 839
 840 #define MAJOR_OBJ_IS_IN_TO_SPACE(obj)   FALSE
 841
 842 /*
 843  * obj is some object.  If it's not in the major heap (i.e. if it's in
 844  * the nursery or LOS), return FALSE.  Otherwise return whether it's
 845  * been marked or copied.
 846  */
 847 static gboolean
 848 major_is_object_live (char *obj)
 849 {
 850         MSBlockInfo *block;
 851         int word, bit;
 852 #ifndef FIXED_HEAP
 853         mword objsize;
 854 #endif
 855
 856         if (sgen_ptr_in_nursery (obj))
 857                 return FALSE;
 858
 859 #ifdef FIXED_HEAP
 860         /* LOS */
 861         if (!MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
 862                 return FALSE;
 863 #else
 864         objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 865
 866         /* LOS */
 867         if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
 868                 return FALSE;
 869 #endif
 870
 871         /* now we know it's in a major block */
 872         block = MS_BLOCK_FOR_OBJ (obj);
 873         DEBUG (9, g_assert (!block->pinned));
 874         MS_CALC_MARK_BIT (word, bit, obj);
 875         return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
 876 }
 877
 878 static gboolean
 879 major_ptr_is_in_non_pinned_space (char *ptr)
 880 {
 881         MSBlockInfo *block;
 882
 883         FOREACH_BLOCK (block) {
 884                 if (ptr >= block->block && ptr <= block->block + MS_BLOCK_SIZE)
 885                         return !block->pinned;
 886         } END_FOREACH_BLOCK;
 887         return FALSE;
 888 }
 889
 890 static void
 891 major_iterate_objects (gboolean non_pinned, gboolean pinned, IterateObjectCallbackFunc callback, void *data)
 892 {
 893         MSBlockInfo *block;
 894
 895         ms_wait_for_sweep_done ();
 896
 897         FOREACH_BLOCK (block) {
 898                 int count = MS_BLOCK_FREE / block->obj_size;
 899                 int i;
 900
 901                 if (block->pinned && !pinned)
 902                         continue;
 903                 if (!block->pinned && !non_pinned)
 904                         continue;
 905
 906                 for (i = 0; i < count; ++i) {
 907                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 908                         if (MS_OBJ_ALLOCED (obj, block))
 909                                 callback ((char*)obj, block->obj_size, data);
 910                 }
 911         } END_FOREACH_BLOCK;
 912 }
 913
 914 static gboolean
 915 major_is_valid_object (char *object)
 916 {
 917         MSBlockInfo *block;
 918
 919         ms_wait_for_sweep_done ();
 920         FOREACH_BLOCK (block) {
 921                 int idx;
 922                 char *obj;
 923
 924                 if ((block->block > object) || ((block->block + MS_BLOCK_SIZE) <= object))
 925                         continue;
 926
 927                 idx = MS_BLOCK_OBJ_INDEX (object, block);
 928                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 929                 if (obj != object)
 930                         return FALSE;
 931                 return MS_OBJ_ALLOCED (obj, block);
 932         } END_FOREACH_BLOCK;
 933
 934         return FALSE;
 935 }
 936
 937
 938 static gboolean
 939 major_describe_pointer (char *ptr)
 940 {
 941         MSBlockInfo *block;
 942
 943         FOREACH_BLOCK (block) {
 944                 int idx;
 945                 char *obj;
 946                 gboolean live;
 947                 MonoVTable *vtable;
 948
 949                 if ((block->block > ptr) || ((block->block + MS_BLOCK_SIZE) <= ptr))
 950                         continue;
 951
 952                 fprintf (gc_debug_file, "major-ptr (block %p sz %d pin %d ref %d) ",
 953                         block->block, block->obj_size, block->pinned, block->has_references);
 954
 955                 idx = MS_BLOCK_OBJ_INDEX (ptr, block);
 956                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 957                 live = MS_OBJ_ALLOCED (obj, block);
 958                 vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
 959
 960                 if (obj == ptr) {
 961                         if (live)
 962                                 fprintf (gc_debug_file, "(object %s.%s)", vtable->klass->name_space, vtable->klass->name);
 963                         else
 964                                 fprintf (gc_debug_file, "(dead-object)");
 965                 } else {
 966                         if (live)
 967                                 fprintf (gc_debug_file, "(interior-ptr offset %td of %p %s.%s)",
 968                                         ptr - obj,
 969                                         obj, vtable->klass->name_space, vtable->klass->name);
 970                         else
 971                                 fprintf (gc_debug_file, "(dead-interior-ptr to %td to %p)",
 972                                         ptr - obj, obj);
 973                 }
 974
 975                 return TRUE;
 976         } END_FOREACH_BLOCK;
 977
 978         return FALSE;
 979 }
 980
 981 static void
 982 major_check_scan_starts (void)
 983 {
 984 }
 985
 986 static void
 987 major_dump_heap (FILE *heap_dump_file)
 988 {
 989         MSBlockInfo *block;
 990         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
 991         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
 992         int i;
 993
 994         for (i = 0; i < num_block_obj_sizes; ++i)
 995                 slots_available [i] = slots_used [i] = 0;
 996
 997         FOREACH_BLOCK (block) {
 998                 int index = ms_find_block_obj_size_index (block->obj_size);
 999                 int count = MS_BLOCK_FREE / block->obj_size;
1000
1001                 slots_available [index] += count;
1002                 for (i = 0; i < count; ++i) {
1003                         if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
1004                                 ++slots_used [index];
1005                 }
1006         } END_FOREACH_BLOCK;
1007
1008         fprintf (heap_dump_file, "<occupancies>\n");
1009         for (i = 0; i < num_block_obj_sizes; ++i) {
1010                 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
1011                                 block_obj_sizes [i], slots_available [i], slots_used [i]);
1012         }
1013         fprintf (heap_dump_file, "</occupancies>\n");
1014
1015         FOREACH_BLOCK (block) {
1016                 int count = MS_BLOCK_FREE / block->obj_size;
1017                 int i;
1018                 int start = -1;
1019
1020                 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
1021
1022                 for (i = 0; i <= count; ++i) {
1023                         if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
1024                                 if (start < 0)
1025                                         start = i;
1026                         } else {
1027                                 if (start >= 0) {
1028                                         sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), block->block);
1029                                         start = -1;
1030                                 }
1031                         }
1032                 }
1033
1034                 fprintf (heap_dump_file, "</section>\n");
1035         } END_FOREACH_BLOCK;
1036 }
1037
1038 #define LOAD_VTABLE     SGEN_LOAD_VTABLE
1039
1040 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,block,queue) do {        \
1041                 int __word, __bit;                                      \
1042                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
1043                 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
1044                         MS_SET_MARK_BIT ((block), __word, __bit);       \
1045                         if ((block)->has_references)                    \
1046                                 GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
1047                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
1048                 }                                                       \
1049         } while (0)
1050 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do {                \
1051                 int __word, __bit;                                      \
1052                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
1053                 DEBUG (9, g_assert (MS_OBJ_ALLOCED ((obj), (block))));  \
1054                 if (!MS_MARK_BIT ((block), __word, __bit)) {            \
1055                         MS_SET_MARK_BIT ((block), __word, __bit);       \
1056                         if ((block)->has_references)                    \
1057                                 GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
1058                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
1059                 }                                                       \
1060         } while (0)
1061 #define MS_PAR_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do {            \
1062                 int __word, __bit;                                      \
1063                 gboolean __was_marked;                                  \
1064                 DEBUG (9, g_assert (MS_OBJ_ALLOCED ((obj), (block))));  \
1065                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
1066                 MS_PAR_SET_MARK_BIT (__was_marked, (block), __word, __bit); \
1067                 if (!__was_marked) {                                    \
1068                         if ((block)->has_references)                    \
1069                                 GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
1070                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
1071                 }                                                       \
1072         } while (0)
1073
1074 static void
1075 pin_major_object (char *obj, SgenGrayQueue *queue)
1076 {
1077         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1078         block->has_pinned = TRUE;
1079         MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1080 }
1081
1082 #include "sgen-major-copy-object.h"
1083
1084 #ifdef SGEN_PARALLEL_MARK
1085 static void
1086 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1087 {
1088         void *obj = *ptr;
1089         mword objsize;
1090         MSBlockInfo *block;
1091         MonoVTable *vt;
1092
1093         HEAVY_STAT (++stat_copy_object_called_major);
1094
1095         DEBUG (9, g_assert (obj));
1096         DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
1097
1098         if (sgen_ptr_in_nursery (obj)) {
1099                 int word, bit;
1100                 gboolean has_references;
1101                 void *destination;
1102                 mword vtable_word = *(mword*)obj;
1103                 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1104
1105                 if (vtable_word & SGEN_FORWARDED_BIT) {
1106                         *ptr = (void*)vt;
1107                         return;
1108                 }
1109
1110                 if (vtable_word & SGEN_PINNED_BIT)
1111                         return;
1112
1113                 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
1114                 if (sgen_nursery_is_to_space (obj))
1115                         return;
1116
1117                 HEAVY_STAT (++stat_objects_copied_major);
1118
1119         do_copy_object:
1120                 objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
1121                 has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
1122
1123                 destination = sgen_minor_collector.par_alloc_for_promotion (obj, objsize, has_references);
1124                 if (G_UNLIKELY (!destination)) {
1125                         if (!sgen_ptr_in_nursery (obj)) {
1126                                 int size_index;
1127                                 block = MS_BLOCK_FOR_OBJ (obj);
1128                                 size_index = block->obj_size_index;
1129                                 evacuate_block_obj_sizes [size_index] = FALSE;
1130                         }
1131
1132                         sgen_parallel_pin_or_update (ptr, obj, vt, queue);
1133                         sgen_set_pinned_from_failed_allocation (objsize);
1134                         return;
1135                 }
1136
1137                 /*
1138                  * We do this before the CAS because we want to make
1139                  * sure that if another thread sees the destination
1140                  * pointer the VTable is already in place.  Not doing
1141                  * this can crash binary protocols.
1142                  */
1143                 *(MonoVTable**)destination = vt;
1144
1145                 if (SGEN_CAS_PTR (obj, (void*)((mword)destination | SGEN_FORWARDED_BIT), vt) == vt) {
1146                         gboolean was_marked;
1147
1148                         par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
1149                         obj = destination;
1150                         *ptr = obj;
1151
1152                         /*
1153                          * FIXME: If we make major_alloc_object() give
1154                          * us the block info, too, we won't have to
1155                          * re-fetch it here.
1156                          *
1157                          * FIXME (2): We should rework this to avoid all those nursery checks.
1158                          */
1159                         /*
1160                          * For the split nursery allocator the object
1161                          * might still be in the nursery despite
1162                          * having being promoted, in which case we
1163                          * can't mark it.
1164                          */
1165                         if (!sgen_ptr_in_nursery (obj)) {
1166                                 block = MS_BLOCK_FOR_OBJ (obj);
1167                                 MS_CALC_MARK_BIT (word, bit, obj);
1168                                 DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
1169                                 MS_PAR_SET_MARK_BIT (was_marked, block, word, bit);
1170                         }
1171                 } else {
1172                         /*
1173                          * FIXME: We have allocated destination, but
1174                          * we cannot use it.  Give it back to the
1175                          * allocator.
1176                          */
1177                         *(void**)destination = NULL;
1178
1179                         vtable_word = *(mword*)obj;
1180                         g_assert (vtable_word & SGEN_FORWARDED_BIT);
1181
1182                         obj = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1183
1184                         *ptr = obj;
1185
1186                         HEAVY_STAT (++stat_slots_allocated_in_vain);
1187                 }
1188         } else {
1189 #ifdef FIXED_HEAP
1190                 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1191 #else
1192                 mword vtable_word = *(mword*)obj;
1193                 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1194
1195                 /* see comment in the non-parallel version below */
1196                 if (vtable_word & SGEN_FORWARDED_BIT) {
1197                         *ptr = (void*)vt;
1198                         return;
1199                 }
1200                 objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
1201
1202                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1203 #endif
1204                 {
1205                         int size_index;
1206
1207                         block = MS_BLOCK_FOR_OBJ (obj);
1208                         size_index = block->obj_size_index;
1209
1210                         if (!block->has_pinned && evacuate_block_obj_sizes [size_index]) {
1211                                 if (block->is_to_space)
1212                                         return;
1213
1214 #ifdef FIXED_HEAP
1215                                 {
1216                                         mword vtable_word = *(mword*)obj;
1217                                         vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1218
1219                                         if (vtable_word & SGEN_FORWARDED_BIT) {
1220                                                 *ptr = (void*)vt;
1221                                                 return;
1222                                         }
1223                                 }
1224 #endif
1225
1226                                 HEAVY_STAT (++stat_major_objects_evacuated);
1227                                 goto do_copy_object;
1228                         }
1229
1230                         MS_PAR_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1231                 } else {
1232 #ifdef FIXED_HEAP
1233                         mword vtable_word = *(mword*)obj;
1234                         vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1235 #endif
1236
1237                         if (vtable_word & SGEN_PINNED_BIT)
1238                                 return;
1239                         binary_protocol_pin (obj, vt, sgen_safe_object_get_size ((MonoObject*)obj));
1240                         if (SGEN_CAS_PTR (obj, (void*)(vtable_word | SGEN_PINNED_BIT), (void*)vtable_word) == (void*)vtable_word) {
1241                                 if (SGEN_VTABLE_HAS_REFERENCES (vt))
1242                                         GRAY_OBJECT_ENQUEUE (queue, obj);
1243                         } else {
1244                                 g_assert (SGEN_OBJECT_IS_PINNED (obj));
1245                         }
1246                 }
1247         }
1248 }
1249 #else
1250 static void
1251 major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
1252 {
1253         void *obj = *ptr;
1254         MSBlockInfo *block;
1255
1256         HEAVY_STAT (++stat_copy_object_called_major);
1257
1258         DEBUG (9, g_assert (obj));
1259         DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
1260
1261         if (sgen_ptr_in_nursery (obj)) {
1262                 int word, bit;
1263                 char *forwarded, *old_obj;
1264
1265                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1266                         *ptr = forwarded;
1267                         return;
1268                 }
1269                 if (SGEN_OBJECT_IS_PINNED (obj))
1270                         return;
1271
1272                 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
1273                 if (sgen_nursery_is_to_space (obj))
1274                         return;
1275
1276                 HEAVY_STAT (++stat_objects_copied_major);
1277
1278         do_copy_object:
1279                 old_obj = obj;
1280                 obj = copy_object_no_checks (obj, queue);
1281                 if (G_UNLIKELY (old_obj == obj)) {
1282                         /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
1283                         if (!sgen_ptr_in_nursery (obj)) {
1284                                 int size_index;
1285                                 block = MS_BLOCK_FOR_OBJ (obj);
1286                                 size_index = block->obj_size_index;
1287                                 evacuate_block_obj_sizes [size_index] = FALSE;
1288                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1289                         }
1290                         return;
1291                 }
1292                 *ptr = obj;
1293
1294                 /*
1295                  * FIXME: See comment for copy_object_no_checks().  If
1296                  * we have that, we can let the allocation function
1297                  * give us the block info, too, and we won't have to
1298                  * re-fetch it.
1299                  *
1300                  * FIXME (2): We should rework this to avoid all those nursery checks.
1301                  */
1302                 /*
1303                  * For the split nursery allocator the object might
1304                  * still be in the nursery despite having being
1305                  * promoted, in which case we can't mark it.
1306                  */
1307                 if (!sgen_ptr_in_nursery (obj)) {
1308                         block = MS_BLOCK_FOR_OBJ (obj);
1309                         MS_CALC_MARK_BIT (word, bit, obj);
1310                         DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
1311                         MS_SET_MARK_BIT (block, word, bit);
1312                 }
1313         } else {
1314                 char *forwarded;
1315 #ifdef FIXED_HEAP
1316                 if (MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
1317 #else
1318                 mword objsize;
1319
1320                 /*
1321                  * If we have don't have a fixed heap we cannot know
1322                  * whether an object is in the LOS or in the small
1323                  * object major heap without checking its size.  To do
1324                  * that, however, we need to know that we actually
1325                  * have a valid object, not a forwarding pointer, so
1326                  * we have to do this check first.
1327                  */
1328                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1329                         *ptr = forwarded;
1330                         return;
1331                 }
1332
1333                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
1334
1335                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
1336 #endif
1337                 {
1338                         int size_index;
1339                         gboolean evacuate;
1340
1341                         block = MS_BLOCK_FOR_OBJ (obj);
1342                         size_index = block->obj_size_index;
1343                         evacuate = evacuate_block_obj_sizes [size_index];
1344
1345 #ifdef FIXED_HEAP
1346                         /*
1347                          * We could also check for !block->has_pinned
1348                          * here, but it would only make an uncommon case
1349                          * faster, namely objects that are in blocks
1350                          * whose slot sizes are evacuated but which have
1351                          * pinned objects.
1352                          */
1353                         if (evacuate && (forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1354                                 *ptr = forwarded;
1355                                 return;
1356                         }
1357 #endif
1358
1359                         if (evacuate && !block->has_pinned) {
1360                                 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1361                                 if (block->is_to_space)
1362                                         return;
1363                                 HEAVY_STAT (++stat_major_objects_evacuated);
1364                                 goto do_copy_object;
1365                         } else {
1366                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
1367                         }
1368                 } else {
1369                         if (SGEN_OBJECT_IS_PINNED (obj))
1370                                 return;
1371                         binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1372                         SGEN_PIN_OBJECT (obj);
1373                         /* FIXME: only enqueue if object has references */
1374                         GRAY_OBJECT_ENQUEUE (queue, obj);
1375                 }
1376         }
1377 }
1378 #endif
1379
1380 #include "sgen-major-scan-object.h"
1381
1382 static void
1383 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
1384 {
1385         int i;
1386         int last_index = -1;
1387
1388         if (!block->pin_queue_num_entries)
1389                 return;
1390
1391         block->has_pinned = TRUE;
1392
1393         for (i = 0; i < block->pin_queue_num_entries; ++i) {
1394                 int index = MS_BLOCK_OBJ_INDEX (block->pin_queue_start [i], block);
1395                 DEBUG (9, g_assert (index >= 0 && index < MS_BLOCK_FREE / block->obj_size));
1396                 if (index == last_index)
1397                         continue;
1398                 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (MS_BLOCK_OBJ (block, index), block, queue);
1399                 last_index = index;
1400         }
1401 }
1402
1403 static void
1404 ms_sweep (void)
1405 {
1406         int i;
1407         MSBlockInfo **iter;
1408
1409         /* statistics for evacuation */
1410         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1411         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1412         int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1413
1414         for (i = 0; i < num_block_obj_sizes; ++i)
1415                 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1416
1417         /* clear all the free lists */
1418         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1419                 MSBlockInfo **free_blocks = free_block_lists [i];
1420                 int j;
1421                 for (j = 0; j < num_block_obj_sizes; ++j)
1422                         free_blocks [j] = NULL;
1423         }
1424
1425         /* traverse all blocks, free and zero unmarked objects */
1426         iter = &all_blocks;
1427         while (*iter) {
1428                 MSBlockInfo *block = *iter;
1429                 int count;
1430                 gboolean have_live = FALSE;
1431                 gboolean has_pinned;
1432                 int obj_index;
1433                 int obj_size_index;
1434
1435                 obj_size_index = block->obj_size_index;
1436
1437                 has_pinned = block->has_pinned;
1438                 block->has_pinned = block->pinned;
1439
1440                 block->is_to_space = FALSE;
1441
1442                 count = MS_BLOCK_FREE / block->obj_size;
1443                 block->free_list = NULL;
1444
1445                 for (obj_index = 0; obj_index < count; ++obj_index) {
1446                         int word, bit;
1447                         void *obj = MS_BLOCK_OBJ (block, obj_index);
1448
1449                         MS_CALC_MARK_BIT (word, bit, obj);
1450                         if (MS_MARK_BIT (block, word, bit)) {
1451                                 DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
1452                                 have_live = TRUE;
1453                                 if (!has_pinned)
1454                                         ++slots_used [obj_size_index];
1455                         } else {
1456                                 /* an unmarked object */
1457                                 if (MS_OBJ_ALLOCED (obj, block)) {
1458                                         binary_protocol_empty (obj, block->obj_size);
1459                                         memset (obj, 0, block->obj_size);
1460                                 }
1461                                 *(void**)obj = block->free_list;
1462                                 block->free_list = obj;
1463                         }
1464                 }
1465
1466                 /* reset mark bits */
1467                 memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1468
1469                 /*
1470                  * FIXME: reverse free list so that it's in address
1471                  * order
1472                  */
1473
1474                 if (have_live) {
1475                         if (!has_pinned) {
1476                                 ++num_blocks [obj_size_index];
1477                                 slots_available [obj_size_index] += count;
1478                         }
1479
1480                         iter = &block->next;
1481
1482                         /*
1483                          * If there are free slots in the block, add
1484                          * the block to the corresponding free list.
1485                          */
1486                         if (block->free_list) {
1487                                 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1488                                 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1489                                 block->next_free = free_blocks [index];
1490                                 free_blocks [index] = block;
1491                         }
1492
1493                         update_heap_boundaries_for_block (block);
1494                 } else {
1495                         /*
1496                          * Blocks without live objects are removed from the
1497                          * block list and freed.
1498                          */
1499                         *iter = block->next;
1500
1501 #ifdef FIXED_HEAP
1502                         ms_free_block (block);
1503 #else
1504                         ms_free_block (block->block);
1505
1506                         sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
1507 #endif
1508
1509                         --num_major_sections;
1510                 }
1511         }
1512
1513         for (i = 0; i < num_block_obj_sizes; ++i) {
1514                 float usage = (float)slots_used [i] / (float)slots_available [i];
1515                 if (num_blocks [i] > 5 && usage < evacuation_threshold) {
1516                         evacuate_block_obj_sizes [i] = TRUE;
1517                         /*
1518                         g_print ("slot size %d - %d of %d used\n",
1519                                         block_obj_sizes [i], slots_used [i], slots_available [i]);
1520                         */
1521                 } else {
1522                         evacuate_block_obj_sizes [i] = FALSE;
1523                 }
1524         }
1525
1526         have_swept = TRUE;
1527 }
1528
1529 static mono_native_thread_return_t
1530 ms_sweep_thread_func (void *dummy)
1531 {
1532         g_assert (concurrent_sweep);
1533
1534         for (;;) {
1535                 int result;
1536
1537                 while ((result = MONO_SEM_WAIT (&ms_sweep_cmd_semaphore)) != 0) {
1538                         if (errno != EINTR)
1539                                 g_error ("MONO_SEM_WAIT FAILED with %d errno %d (%s)", result, errno, strerror (errno));
1540                 }
1541
1542                 ms_sweep ();
1543
1544                 ms_signal_sweep_done ();
1545         }
1546
1547         return NULL;
1548 }
1549
1550 static void
1551 major_sweep (void)
1552 {
1553         if (concurrent_sweep) {
1554                 g_assert (ms_sweep_thread);
1555                 ms_signal_sweep_command ();
1556         } else {
1557                 ms_sweep ();
1558         }
1559 }
1560
1561 static int count_pinned_ref;
1562 static int count_pinned_nonref;
1563 static int count_nonpinned_ref;
1564 static int count_nonpinned_nonref;
1565
1566 static void
1567 count_nonpinned_callback (char *obj, size_t size, void *data)
1568 {
1569         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1570
1571         if (vtable->klass->has_references)
1572                 ++count_nonpinned_ref;
1573         else
1574                 ++count_nonpinned_nonref;
1575 }
1576
1577 static void
1578 count_pinned_callback (char *obj, size_t size, void *data)
1579 {
1580         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1581
1582         if (vtable->klass->has_references)
1583                 ++count_pinned_ref;
1584         else
1585                 ++count_pinned_nonref;
1586 }
1587
1588 static void __attribute__ ((unused))
1589 count_ref_nonref_objs (void)
1590 {
1591         int total;
1592
1593         count_pinned_ref = 0;
1594         count_pinned_nonref = 0;
1595         count_nonpinned_ref = 0;
1596         count_nonpinned_nonref = 0;
1597
1598         major_iterate_objects (TRUE, FALSE, count_nonpinned_callback, NULL);
1599         major_iterate_objects (FALSE, TRUE, count_pinned_callback, NULL);
1600
1601         total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1602
1603         g_print ("ref: %d pinned %d non-pinned   non-ref: %d pinned %d non-pinned  --  %.1f\n",
1604                         count_pinned_ref, count_nonpinned_ref,
1605                         count_pinned_nonref, count_nonpinned_nonref,
1606                         (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1607 }
1608
1609 static int
1610 ms_calculate_block_obj_sizes (double factor, int *arr)
1611 {
1612         double target_size = sizeof (MonoObject);
1613         int num_sizes = 0;
1614         int last_size = 0;
1615
1616         do {
1617                 int target_count = ceil (MS_BLOCK_FREE / target_size);
1618                 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1619
1620                 if (size != last_size) {
1621                         if (arr)
1622                                 arr [num_sizes] = size;
1623                         ++num_sizes;
1624                         last_size = size;
1625                 }
1626
1627                 target_size *= factor;
1628         } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1629
1630         return num_sizes;
1631 }
1632
1633 /* only valid during minor collections */
1634 static int old_num_major_sections;
1635
1636 static void
1637 major_start_nursery_collection (void)
1638 {
1639         ms_wait_for_sweep_done ();
1640
1641 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1642         consistency_check ();
1643 #endif
1644
1645         old_num_major_sections = num_major_sections;
1646 }
1647
1648 static void
1649 major_finish_nursery_collection (void)
1650 {
1651 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1652         consistency_check ();
1653 #endif
1654         sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1655 }
1656
1657 static void
1658 major_start_major_collection (void)
1659 {
1660         int i;
1661
1662         ms_wait_for_sweep_done ();
1663
1664         /* clear the free lists */
1665         for (i = 0; i < num_block_obj_sizes; ++i) {
1666                 if (!evacuate_block_obj_sizes [i])
1667                         continue;
1668
1669                 free_block_lists [0][i] = NULL;
1670                 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1671         }
1672 }
1673
1674 static void
1675 major_finish_major_collection (void)
1676 {
1677 }
1678
1679 static void
1680 major_have_computer_minor_collection_allowance (void)
1681 {
1682 #ifndef FIXED_HEAP
1683         int section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1684
1685         g_assert (have_swept);
1686         ms_wait_for_sweep_done ();
1687         g_assert (!ms_sweep_in_progress);
1688
1689         /*
1690          * FIXME: We don't free blocks on 32 bit platforms because it
1691          * can lead to address space fragmentation, since we're
1692          * allocating blocks in larger contingents.
1693          */
1694         if (sizeof (mword) < 8)
1695                 return;
1696
1697         while (num_empty_blocks > section_reserve) {
1698                 void *next = *(void**)empty_blocks;
1699                 sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE);
1700                 empty_blocks = next;
1701                 /*
1702                  * Needs not be atomic because this is running
1703                  * single-threaded.
1704                  */
1705                 --num_empty_blocks;
1706
1707                 ++stat_major_blocks_freed;
1708         }
1709 #endif
1710 }
1711
1712 static void
1713 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
1714 {
1715         MSBlockInfo *block;
1716
1717         FOREACH_BLOCK (block) {
1718                 block->pin_queue_start = sgen_find_optimized_pin_queue_area (block->block + MS_BLOCK_SKIP, block->block + MS_BLOCK_SIZE,
1719                                 &block->pin_queue_num_entries);
1720         } END_FOREACH_BLOCK;
1721 }
1722
1723 static void
1724 major_pin_objects (SgenGrayQueue *queue)
1725 {
1726         MSBlockInfo *block;
1727
1728         FOREACH_BLOCK (block) {
1729                 mark_pinned_objects_in_block (block, queue);
1730         } END_FOREACH_BLOCK;
1731 }
1732
1733 static void
1734 major_init_to_space (void)
1735 {
1736 }
1737
1738 static void
1739 major_report_pinned_memory_usage (void)
1740 {
1741         g_assert_not_reached ();
1742 }
1743
1744 static gint64
1745 major_get_used_size (void)
1746 {
1747         gint64 size = 0;
1748         MSBlockInfo *block;
1749
1750         FOREACH_BLOCK (block) {
1751                 int count = MS_BLOCK_FREE / block->obj_size;
1752                 void **iter;
1753                 size += count * block->obj_size;
1754                 for (iter = block->free_list; iter; iter = (void**)*iter)
1755                         size -= block->obj_size;
1756         } END_FOREACH_BLOCK;
1757
1758         return size;
1759 }
1760
1761 static int
1762 get_num_major_sections (void)
1763 {
1764         return num_major_sections;
1765 }
1766
1767 static gboolean
1768 major_handle_gc_param (const char *opt)
1769 {
1770 #ifdef FIXED_HEAP
1771         if (g_str_has_prefix (opt, "major-heap-size=")) {
1772                 const char *arg = strchr (opt, '=') + 1;
1773                 glong size;
1774                 if (!mono_gc_parse_environment_string_extract_number (arg, &size))
1775                         return FALSE;
1776                 ms_heap_num_blocks = (size + MS_BLOCK_SIZE - 1) / MS_BLOCK_SIZE;
1777                 g_assert (ms_heap_num_blocks > 0);
1778                 return TRUE;
1779         } else
1780 #endif
1781         if (g_str_has_prefix (opt, "evacuation-threshold=")) {
1782                 const char *arg = strchr (opt, '=') + 1;
1783                 int percentage = atoi (arg);
1784                 if (percentage < 0 || percentage > 100) {
1785                         fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
1786                         exit (1);
1787                 }
1788                 evacuation_threshold = (float)percentage / 100.0;
1789                 return TRUE;
1790         } else if (!strcmp (opt, "concurrent-sweep")) {
1791                 concurrent_sweep = TRUE;
1792                 return TRUE;
1793         } else if (!strcmp (opt, "no-concurrent-sweep")) {
1794                 concurrent_sweep = FALSE;
1795                 return TRUE;
1796         }
1797
1798         return FALSE;
1799 }
1800
1801 static void
1802 major_print_gc_param_usage (void)
1803 {
1804         fprintf (stderr,
1805                         ""
1806 #ifdef FIXED_HEAP
1807                         "  major-heap-size=N (where N is an integer, possibly with a k, m or a g suffix)\n"
1808 #endif
1809                         "  evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
1810                         "  (no-)concurrent-sweep\n"
1811                         );
1812 }
1813
1814 #ifdef SGEN_HAVE_CARDTABLE
1815 static void
1816 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
1817 {
1818         MSBlockInfo *block;
1819
1820         FOREACH_BLOCK (block) {
1821                 if (block->has_references)
1822                         callback ((mword)block->block, MS_BLOCK_SIZE);
1823         } END_FOREACH_BLOCK;
1824 }
1825
1826 #ifdef HEAVY_STATISTICS
1827 extern long long marked_cards;
1828 extern long long scanned_cards;
1829 extern long long scanned_objects;
1830 extern long long remarked_cards;
1831 #endif
1832
1833 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
1834 /*
1835  * MS blocks are 16K aligned.
1836  * Cardtables are 4K aligned, at least.
1837  * This means that the cardtable of a given block is 32 bytes aligned.
1838  */
1839 static guint8*
1840 initial_skip_card (guint8 *card_data)
1841 {
1842         mword *cards = (mword*)card_data;
1843         mword card;
1844         int i;
1845         for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
1846                 card = cards [i];
1847                 if (card)
1848                         break;
1849         }
1850
1851         if (i == CARD_WORDS_PER_BLOCK)
1852                 return card_data + CARDS_PER_BLOCK;
1853
1854 #if defined(__i386__) && defined(__GNUC__)
1855         return card_data + i * 4 +  (__builtin_ffs (card) - 1) / 8;
1856 #elif defined(__x86_64__) && defined(__GNUC__)
1857         return card_data + i * 8 +  (__builtin_ffsll (card) - 1) / 8;
1858 #elif defined(__s390x__) && defined(__GNUC__)
1859         return card_data + i * 8 +  (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1860 #else
1861         for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
1862                 if (card_data [i])
1863                         return &card_data [i];
1864         }
1865         return card_data;
1866 #endif
1867 }
1868
1869
1870 static G_GNUC_UNUSED guint8*
1871 skip_card (guint8 *card_data, guint8 *card_data_end)
1872 {
1873         while (card_data < card_data_end && !*card_data)
1874                 ++card_data;
1875         return card_data;
1876 }
1877
1878 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
1879 #define MS_BLOCK_OBJ_FAST(b,os,i)                       ((b) + MS_BLOCK_SKIP + (os) * (i))
1880 #define MS_OBJ_ALLOCED_FAST(o,b)                (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
1881
1882 static void
1883 major_scan_card_table (SgenGrayQueue *queue)
1884 {
1885         MSBlockInfo *block;
1886         ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
1887
1888         FOREACH_BLOCK (block) {
1889                 int block_obj_size;
1890                 char *block_start;
1891
1892                 if (!block->has_references)
1893                         continue;
1894
1895                 block_obj_size = block->obj_size;
1896                 block_start = block->block;
1897
1898                 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
1899                         guint8 *cards;
1900 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
1901                         guint8 cards_data [CARDS_PER_BLOCK];
1902 #endif
1903                         char *obj, *end, *base;
1904
1905                         /*We can avoid the extra copy since the remark cardtable was cleaned before */
1906 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1907                         cards = sgen_card_table_get_card_scan_address ((mword)block_start);
1908 #else
1909                         cards = cards_data;
1910                         if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
1911                                 continue;
1912 #endif
1913
1914                         obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
1915                         end = block_start + MS_BLOCK_SIZE;
1916                         base = sgen_card_table_align_pointer (obj);
1917
1918                         while (obj < end) {
1919                                 if (MS_OBJ_ALLOCED_FAST (obj, block_start)) {
1920                                         int card_offset = (obj - base) >> CARD_BITS;
1921                                         sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, queue);
1922                                 }
1923                                 obj += block_obj_size;
1924                         }
1925                 } else {
1926                         guint8 *card_data, *card_base;
1927                         guint8 *card_data_end;
1928
1929                         /*
1930                          * This is safe in face of card aliasing for the following reason:
1931                          *
1932                          * Major blocks are 16k aligned, or 32 cards aligned.
1933                          * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
1934                          * sizes, they won't overflow the cardtable overlap modulus.
1935                          */
1936                         card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
1937                         card_data_end = card_data + CARDS_PER_BLOCK;
1938
1939                         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)) {
1940                                 int index;
1941                                 int idx = card_data - card_base;
1942                                 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
1943                                 char *end = start + CARD_SIZE_IN_BYTES;
1944                                 char *obj;
1945
1946                                 HEAVY_STAT (++scanned_cards);
1947
1948                                 if (!*card_data)
1949                                         continue;
1950
1951                                 HEAVY_STAT (++marked_cards);
1952
1953                                 sgen_card_table_prepare_card_for_scanning (card_data);
1954
1955                                 if (idx == 0)
1956                                         index = 0;
1957                                 else
1958                                         index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
1959
1960                                 obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
1961                                 while (obj < end) {
1962                                         if (MS_OBJ_ALLOCED_FAST (obj, block_start)) {
1963                                                 HEAVY_STAT (++scanned_objects);
1964                                                 scan_func (obj, queue);
1965                                         }
1966                                         obj += block_obj_size;
1967                                 }
1968                                 HEAVY_STAT (if (*card_data) ++remarked_cards);
1969                         }
1970                 }
1971         } END_FOREACH_BLOCK;
1972 }
1973 #endif
1974
1975 static gboolean
1976 major_is_worker_thread (MonoNativeThreadId thread)
1977 {
1978         if (concurrent_sweep)
1979                 return thread == ms_sweep_thread;
1980         else
1981                 return FALSE;
1982 }
1983
1984 static void
1985 alloc_free_block_lists (MSBlockInfo ***lists)
1986 {
1987         int i;
1988         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
1989                 lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
1990 }
1991
1992 #ifdef SGEN_PARALLEL_MARK
1993 static void*
1994 major_alloc_worker_data (void)
1995 {
1996         /* FIXME: free this when the workers come down */
1997         MSBlockInfo ***lists = malloc (sizeof (MSBlockInfo**) * MS_BLOCK_TYPE_MAX);
1998         alloc_free_block_lists (lists);
1999         return lists;
2000 }
2001
2002 static void
2003 major_init_worker_thread (void *data)
2004 {
2005         MSBlockInfo ***lists = data;
2006         int i;
2007
2008         g_assert (lists && lists != free_block_lists);
2009         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
2010                 int j;
2011                 for (j = 0; j < num_block_obj_sizes; ++j)
2012                         g_assert (!lists [i][j]);
2013         }
2014
2015 #ifdef HAVE_KW_THREAD
2016         workers_free_block_lists = data;
2017 #else
2018         mono_native_tls_set_value (workers_free_block_lists_key, data);
2019 #endif
2020 }
2021
2022 static void
2023 major_reset_worker_data (void *data)
2024 {
2025         MSBlockInfo ***lists = data;
2026         int i;
2027         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
2028                 int j;
2029                 for (j = 0; j < num_block_obj_sizes; ++j)
2030                         lists [i][j] = NULL;
2031         }
2032 }
2033 #endif
2034
2035 #undef pthread_create
2036
2037 static void
2038 post_param_init (void)
2039 {
2040         if (concurrent_sweep) {
2041                 if (!mono_native_thread_create (&ms_sweep_thread, ms_sweep_thread_func, NULL)) {
2042                         fprintf (stderr, "Error: Could not create sweep thread.\n");
2043                         exit (1);
2044                 }
2045         }
2046 }
2047
2048 void
2049 #ifdef SGEN_PARALLEL_MARK
2050 #ifdef FIXED_HEAP
2051 sgen_marksweep_fixed_par_init
2052 #else
2053 sgen_marksweep_par_init
2054 #endif
2055 #else
2056 #ifdef FIXED_HEAP
2057 sgen_marksweep_fixed_init
2058 #else
2059 sgen_marksweep_init
2060 #endif
2061 #endif
2062         (SgenMajorCollector *collector)
2063 {
2064         int i;
2065
2066 #ifndef FIXED_HEAP
2067         sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
2068 #endif
2069
2070         num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
2071         block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
2072         ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
2073
2074         evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
2075         for (i = 0; i < num_block_obj_sizes; ++i)
2076                 evacuate_block_obj_sizes [i] = FALSE;
2077
2078         /*
2079         {
2080                 int i;
2081                 g_print ("block object sizes:\n");
2082                 for (i = 0; i < num_block_obj_sizes; ++i)
2083                         g_print ("%d\n", block_obj_sizes [i]);
2084         }
2085         */
2086
2087         alloc_free_block_lists (free_block_lists);
2088
2089         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
2090                 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
2091         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
2092                 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
2093
2094 #ifdef SGEN_PARALLEL_MARK
2095         LOCK_INIT (ms_block_list_mutex);
2096 #endif
2097
2098         mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
2099         mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
2100         mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
2101         mono_counters_register ("Wait for sweep time", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &stat_time_wait_for_sweep);
2102 #ifdef SGEN_PARALLEL_MARK
2103 #ifndef HAVE_KW_THREAD
2104         mono_native_tls_alloc (&workers_free_block_lists_key, NULL);
2105 #endif
2106 #endif
2107
2108         /*
2109          * FIXME: These are superfluous if concurrent sweep is
2110          * disabled.  We might want to create them lazily.
2111          */
2112         MONO_SEM_INIT (&ms_sweep_cmd_semaphore, 0);
2113         MONO_SEM_INIT (&ms_sweep_done_semaphore, 0);
2114
2115         collector->section_size = MAJOR_SECTION_SIZE;
2116 #ifdef SGEN_PARALLEL_MARK
2117         collector->is_parallel = TRUE;
2118         collector->alloc_worker_data = major_alloc_worker_data;
2119         collector->init_worker_thread = major_init_worker_thread;
2120         collector->reset_worker_data = major_reset_worker_data;
2121 #else
2122         collector->is_parallel = FALSE;
2123 #endif
2124         collector->supports_cardtable = TRUE;
2125
2126         collector->have_swept = &have_swept;
2127
2128         collector->alloc_heap = major_alloc_heap;
2129         collector->is_object_live = major_is_object_live;
2130         collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2131         collector->alloc_degraded = major_alloc_degraded;
2132
2133         collector->alloc_object = major_alloc_object;
2134 #ifdef SGEN_PARALLEL_MARK
2135         collector->par_alloc_object = major_par_alloc_object;
2136 #endif
2137         collector->free_pinned_object = free_pinned_object;
2138         collector->iterate_objects = major_iterate_objects;
2139         collector->free_non_pinned_object = major_free_non_pinned_object;
2140         collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2141         collector->pin_objects = major_pin_objects;
2142         collector->pin_major_object = pin_major_object;
2143 #ifdef SGEN_HAVE_CARDTABLE
2144         collector->scan_card_table = major_scan_card_table;
2145         collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2146 #endif
2147         collector->init_to_space = major_init_to_space;
2148         collector->sweep = major_sweep;
2149         collector->check_scan_starts = major_check_scan_starts;
2150         collector->dump_heap = major_dump_heap;
2151         collector->get_used_size = major_get_used_size;
2152         collector->start_nursery_collection = major_start_nursery_collection;
2153         collector->finish_nursery_collection = major_finish_nursery_collection;
2154         collector->start_major_collection = major_start_major_collection;
2155         collector->finish_major_collection = major_finish_major_collection;
2156         collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2157         collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2158         collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2159         collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2160         collector->get_num_major_sections = get_num_major_sections;
2161         collector->handle_gc_param = major_handle_gc_param;
2162         collector->print_gc_param_usage = major_print_gc_param_usage;
2163         collector->is_worker_thread = major_is_worker_thread;
2164         collector->post_param_init = post_param_init;
2165         collector->is_valid_object = major_is_valid_object;
2166         collector->describe_pointer = major_describe_pointer;
2167
2168         collector->major_ops.copy_or_mark_object = major_copy_or_mark_object;
2169         collector->major_ops.scan_object = major_scan_object;
2170
2171 #ifdef SGEN_HAVE_CARDTABLE
2172         /*cardtable requires major pages to be 8 cards aligned*/
2173         g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);
2174 #endif
2175 }
2176
2177 #endif