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/sgen-layout-stats.h"
  42 #include "metadata/gc-internal.h"
  43 #include "metadata/sgen-pointer-queue.h"
  44 #include "metadata/sgen-pinning.h"
  45 #include "metadata/sgen-workers.h"
  46
  47 #define SGEN_HAVE_CONCURRENT_MARK
  48
  49 #define MS_BLOCK_SIZE   (16*1024)
  50 #define MS_BLOCK_SIZE_SHIFT     14
  51 #define MAJOR_SECTION_SIZE      MS_BLOCK_SIZE
  52 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
  53
  54 /*
  55  * Don't allocate single blocks, but alloc a contingent of this many
  56  * blocks in one swoop.  This must be a power of two.
  57  */
  58 #define MS_BLOCK_ALLOC_NUM      32
  59
  60 /*
  61  * Number of bytes before the first object in a block.  At the start
  62  * of a block is the MSBlockHeader, then opional padding, then come
  63  * the objects, so this must be >= sizeof (MSBlockHeader).
  64  */
  65 #define BLOCK_INFO_IN_HEADER
  66 #define MS_BLOCK_SKIP   ((sizeof (MSBlockHeader) + 15) & ~15)
  67
  68 #define MS_BLOCK_FREE   (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
  69
  70 #define MS_NUM_MARK_WORDS       ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
  71
  72 typedef struct _MSBlockInfo MSBlockInfo;
  73 struct _MSBlockInfo {
  74         int obj_size;
  75         int obj_size_index;
  76         unsigned int pinned : 1;
  77         unsigned int has_references : 1;
  78         unsigned int has_pinned : 1;    /* means cannot evacuate */
  79         unsigned int is_to_space : 1;
  80         unsigned int swept : 1;
  81 #ifndef BLOCK_INFO_IN_HEADER
  82         char *block;
  83 #endif
  84         void **free_list;
  85         MSBlockInfo *next_free;
  86         size_t pin_queue_first_entry;
  87         size_t pin_queue_last_entry;
  88 #ifdef SGEN_HAVE_CONCURRENT_MARK
  89         guint8 *cardtable_mod_union;
  90 #endif
  91         mword mark_words [MS_NUM_MARK_WORDS];
  92 };
  93
  94 #ifdef BLOCK_INFO_IN_HEADER
  95 #define MS_BLOCK_FOR_BLOCK_INFO(b)      ((char*)(b))
  96 #else
  97 #define MS_BLOCK_FOR_BLOCK_INFO(b)      ((b)->block)
  98 #endif
  99
 100 #define MS_BLOCK_OBJ(b,i)               (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (b)->obj_size * (i))
 101 #define MS_BLOCK_OBJ_FOR_SIZE(b,i,obj_size)             (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (obj_size) * (i))
 102 #define MS_BLOCK_DATA_FOR_OBJ(o)        ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
 103
 104 typedef struct {
 105 #ifdef BLOCK_INFO_IN_HEADER
 106         MSBlockInfo info;
 107 #else
 108         MSBlockInfo *info;
 109 #endif
 110 } MSBlockHeader;
 111
 112 #ifdef BLOCK_INFO_IN_HEADER
 113 #define MS_BLOCK_FOR_OBJ(o)             (&((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
 114 #else
 115 #define MS_BLOCK_FOR_OBJ(o)             (((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
 116 #endif
 117
 118 /* object index will always be small */
 119 #define MS_BLOCK_OBJ_INDEX(o,b) ((int)(((char*)(o) - (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP)) / (b)->obj_size))
 120
 121 //casting to int is fine since blocks are 32k
 122 #define MS_CALC_MARK_BIT(w,b,o)         do {                            \
 123                 int i = ((int)((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o)))) >> SGEN_ALLOC_ALIGN_BITS; \
 124                 if (sizeof (mword) == 4) {                              \
 125                         (w) = i >> 5;                                   \
 126                         (b) = i & 31;                                   \
 127                 } else {                                                \
 128                         (w) = i >> 6;                                   \
 129                         (b) = i & 63;                                   \
 130                 }                                                       \
 131         } while (0)
 132
 133 #define MS_MARK_BIT(bl,w,b)     ((bl)->mark_words [(w)] & (ONE_P << (b)))
 134 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (ONE_P << (b)))
 135
 136 #define MS_OBJ_ALLOCED(o,b)     (*(void**)(o) && (*(char**)(o) < MS_BLOCK_FOR_BLOCK_INFO (b) || *(char**)(o) >= MS_BLOCK_FOR_BLOCK_INFO (b) + MS_BLOCK_SIZE))
 137
 138 #define MS_BLOCK_OBJ_SIZE_FACTOR        (sqrt (2.0))
 139
 140 /*
 141  * This way we can lookup block object size indexes for sizes up to
 142  * 256 bytes with a single load.
 143  */
 144 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES      32
 145
 146 static int *block_obj_sizes;
 147 static int num_block_obj_sizes;
 148 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
 149
 150 #define MS_BLOCK_FLAG_PINNED    1
 151 #define MS_BLOCK_FLAG_REFS      2
 152
 153 #define MS_BLOCK_TYPE_MAX       4
 154
 155 static gboolean *evacuate_block_obj_sizes;
 156 static float evacuation_threshold = 0.0f;
 157 #ifdef SGEN_HAVE_CONCURRENT_MARK
 158 static float concurrent_evacuation_threshold = 0.0f;
 159 static gboolean want_evacuation = FALSE;
 160 #endif
 161
 162 static gboolean lazy_sweep = TRUE;
 163 static gboolean have_swept;
 164
 165 #ifdef SGEN_HAVE_CONCURRENT_MARK
 166 static gboolean concurrent_mark;
 167 #endif
 168
 169 #define BLOCK_IS_TAGGED_HAS_REFERENCES(bl)      SGEN_POINTER_IS_TAGGED_1 ((bl))
 170 #define BLOCK_TAG_HAS_REFERENCES(bl)            SGEN_POINTER_TAG_1 ((bl))
 171 #define BLOCK_UNTAG_HAS_REFERENCES(bl)          SGEN_POINTER_UNTAG_1 ((bl))
 172
 173 #define BLOCK_TAG(bl)   ((bl)->has_references ? BLOCK_TAG_HAS_REFERENCES ((bl)) : (bl))
 174
 175 /* all allocated blocks in the system */
 176 static SgenPointerQueue allocated_blocks;
 177
 178 /* non-allocated block free-list */
 179 static void *empty_blocks = NULL;
 180 static size_t num_empty_blocks = 0;
 181
 182 #define FOREACH_BLOCK(bl)       { size_t __index; for (__index = 0; __index < allocated_blocks.next_slot; ++__index) { (bl) = BLOCK_UNTAG_HAS_REFERENCES (allocated_blocks.data [__index]);
 183 #define FOREACH_BLOCK_HAS_REFERENCES(bl,hr)     { size_t __index; for (__index = 0; __index < allocated_blocks.next_slot; ++__index) { (bl) = allocated_blocks.data [__index]; (hr) = BLOCK_IS_TAGGED_HAS_REFERENCES ((bl)); (bl) = BLOCK_UNTAG_HAS_REFERENCES ((bl));
 184 #define END_FOREACH_BLOCK       } }
 185 #define DELETE_BLOCK_IN_FOREACH()       (allocated_blocks.data [__index] = NULL)
 186
 187 static size_t num_major_sections = 0;
 188 /* one free block list for each block object size */
 189 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
 190
 191 static long long stat_major_blocks_alloced = 0;
 192 static long long stat_major_blocks_freed = 0;
 193 static long long stat_major_blocks_lazy_swept = 0;
 194 static long long stat_major_objects_evacuated = 0;
 195
 196 #if SIZEOF_VOID_P != 8
 197 static long long stat_major_blocks_freed_ideal = 0;
 198 static long long stat_major_blocks_freed_less_ideal = 0;
 199 static long long stat_major_blocks_freed_individual = 0;
 200 static long long stat_major_blocks_alloced_less_ideal = 0;
 201 #endif
 202
 203 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
 204 static long long num_major_objects_marked = 0;
 205 #define INC_NUM_MAJOR_OBJECTS_MARKED()  (++num_major_objects_marked)
 206 #else
 207 #define INC_NUM_MAJOR_OBJECTS_MARKED()
 208 #endif
 209
 210 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
 211 static mono_mutex_t scanned_objects_list_lock;
 212 static SgenPointerQueue scanned_objects_list;
 213
 214 static void
 215 add_scanned_object (void *ptr)
 216 {
 217         if (!binary_protocol_is_enabled ())
 218                 return;
 219
 220         mono_mutex_lock (&scanned_objects_list_lock);
 221         sgen_pointer_queue_add (&scanned_objects_list, ptr);
 222         mono_mutex_unlock (&scanned_objects_list_lock);
 223 }
 224 #endif
 225
 226 static void
 227 sweep_block (MSBlockInfo *block, gboolean during_major_collection);
 228
 229 static int
 230 ms_find_block_obj_size_index (size_t size)
 231 {
 232         int i;
 233         SGEN_ASSERT (9, size <= SGEN_MAX_SMALL_OBJ_SIZE, "size %d is bigger than max small object size %d", size, SGEN_MAX_SMALL_OBJ_SIZE);
 234         for (i = 0; i < num_block_obj_sizes; ++i)
 235                 if (block_obj_sizes [i] >= size)
 236                         return i;
 237         g_error ("no object of size %d\n", size);
 238 }
 239
 240 #define FREE_BLOCKS_FROM(lists,p,r)     (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
 241 #define FREE_BLOCKS(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 242
 243 #define MS_BLOCK_OBJ_SIZE_INDEX(s)                              \
 244         (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ?      \
 245          fast_block_obj_size_indexes [((s)+7)>>3] :             \
 246          ms_find_block_obj_size_index ((s)))
 247
 248 static void*
 249 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 250 {
 251         char *start;
 252         if (nursery_align)
 253                 start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 254         else
 255                 start = sgen_alloc_os_memory (nursery_size, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 256
 257         return start;
 258 }
 259
 260 static void
 261 update_heap_boundaries_for_block (MSBlockInfo *block)
 262 {
 263         sgen_update_heap_boundaries ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), (mword)MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE);
 264 }
 265
 266 static void*
 267 ms_get_empty_block (void)
 268 {
 269         char *p;
 270         int i;
 271         void *block, *empty, *next;
 272
 273  retry:
 274         if (!empty_blocks) {
 275                 /*
 276                  * We try allocating MS_BLOCK_ALLOC_NUM blocks first.  If that's
 277                  * unsuccessful, we halve the number of blocks and try again, until we're at
 278                  * 1.  If that doesn't work, either, we assert.
 279                  */
 280                 int alloc_num = MS_BLOCK_ALLOC_NUM;
 281                 for (;;) {
 282                         p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * alloc_num, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE,
 283                                         alloc_num == 1 ? "major heap section" : NULL);
 284                         if (p)
 285                                 break;
 286                         alloc_num >>= 1;
 287                 }
 288
 289                 for (i = 0; i < alloc_num; ++i) {
 290                         block = p;
 291                         /*
 292                          * We do the free list update one after the
 293                          * other so that other threads can use the new
 294                          * blocks as quickly as possible.
 295                          */
 296                         do {
 297                                 empty = empty_blocks;
 298                                 *(void**)block = empty;
 299                         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
 300                         p += MS_BLOCK_SIZE;
 301                 }
 302
 303                 SGEN_ATOMIC_ADD_P (num_empty_blocks, alloc_num);
 304
 305                 stat_major_blocks_alloced += alloc_num;
 306 #if SIZEOF_VOID_P != 8
 307                 if (alloc_num != MS_BLOCK_ALLOC_NUM)
 308                         stat_major_blocks_alloced_less_ideal += alloc_num;
 309 #endif
 310         }
 311
 312         do {
 313                 empty = empty_blocks;
 314                 if (!empty)
 315                         goto retry;
 316                 block = empty;
 317                 next = *(void**)block;
 318         } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
 319
 320         SGEN_ATOMIC_ADD_P (num_empty_blocks, -1);
 321
 322         *(void**)block = NULL;
 323
 324         g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
 325
 326         return block;
 327 }
 328
 329 static void
 330 ms_free_block (void *block)
 331 {
 332         void *empty;
 333
 334         sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 335         memset (block, 0, MS_BLOCK_SIZE);
 336
 337         do {
 338                 empty = empty_blocks;
 339                 *(void**)block = empty;
 340         } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
 341
 342         SGEN_ATOMIC_ADD_P (num_empty_blocks, 1);
 343 }
 344
 345 //#define MARKSWEEP_CONSISTENCY_CHECK
 346
 347 #ifdef MARKSWEEP_CONSISTENCY_CHECK
 348 static void
 349 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
 350 {
 351         MSBlockInfo *b;
 352
 353         for (; block; block = block->next_free) {
 354                 g_assert (block->obj_size == size);
 355                 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
 356
 357                 /* blocks in the free lists must have at least
 358                    one free slot */
 359                 if (block->swept)
 360                         g_assert (block->free_list);
 361
 362                 /* the block must be in the allocated_blocks array */
 363                 g_assert (sgen_pointer_queue_find (&allocated_blocks, BLOCK_TAG (block)) != (size_t)-1);
 364         }
 365 }
 366
 367 static void
 368 check_empty_blocks (void)
 369 {
 370         void *p;
 371         size_t i = 0;
 372         for (p = empty_blocks; p; p = *(void**)p)
 373                 ++i;
 374         g_assert (i == num_empty_blocks);
 375 }
 376
 377 static void
 378 consistency_check (void)
 379 {
 380         MSBlockInfo *block;
 381         int i;
 382
 383         /* check all blocks */
 384         FOREACH_BLOCK (block) {
 385                 int count = MS_BLOCK_FREE / block->obj_size;
 386                 int num_free = 0;
 387                 void **free;
 388
 389                 /* check block header */
 390                 g_assert (((MSBlockHeader*)block->block)->info == block);
 391
 392                 /* count number of free slots */
 393                 for (i = 0; i < count; ++i) {
 394                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 395                         if (!MS_OBJ_ALLOCED (obj, block))
 396                                 ++num_free;
 397                 }
 398
 399                 /* check free list */
 400                 for (free = block->free_list; free; free = (void**)*free) {
 401                         g_assert (MS_BLOCK_FOR_OBJ (free) == block);
 402                         --num_free;
 403                 }
 404                 g_assert (num_free == 0);
 405
 406                 /* check all mark words are zero */
 407                 if (block->swept) {
 408                         for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
 409                                 g_assert (block->mark_words [i] == 0);
 410                 }
 411         } END_FOREACH_BLOCK;
 412
 413         /* check free blocks */
 414         for (i = 0; i < num_block_obj_sizes; ++i) {
 415                 int j;
 416                 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
 417                         check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
 418         }
 419
 420         check_empty_blocks ();
 421 }
 422 #endif
 423
 424 static gboolean
 425 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
 426 {
 427         int size = block_obj_sizes [size_index];
 428         int count = MS_BLOCK_FREE / size;
 429         MSBlockInfo *info;
 430         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 431         char *obj_start;
 432         int i;
 433
 434         if (!sgen_memgov_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
 435                 return FALSE;
 436
 437 #ifdef BLOCK_INFO_IN_HEADER
 438         info = (MSBlockInfo*)ms_get_empty_block ();
 439 #else
 440         {
 441                 MSBlockHeader *header;
 442                 info = sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
 443                 info->block = ms_get_empty_block ();
 444                 header = (MSBlockHeader*)info->block;
 445                 header->info = info;
 446         }
 447 #endif
 448
 449         SGEN_ASSERT (9, count >= 2, "block with %d objects, it must hold at least 2", count);
 450
 451         info->obj_size = size;
 452         info->obj_size_index = size_index;
 453         info->pinned = pinned;
 454         info->has_references = has_references;
 455         info->has_pinned = pinned;
 456         /*
 457          * Blocks that are to-space are not evacuated from.  During an major collection
 458          * blocks are allocated for two reasons: evacuating objects from the nursery and
 459          * evacuating them from major blocks marked for evacuation.  In both cases we don't
 460          * want further evacuation.
 461          */
 462         info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD);
 463         info->swept = 1;
 464 #ifdef SGEN_HAVE_CONCURRENT_MARK
 465         info->cardtable_mod_union = NULL;
 466 #endif
 467
 468         update_heap_boundaries_for_block (info);
 469
 470         /* build free list */
 471         obj_start = MS_BLOCK_FOR_BLOCK_INFO (info) + MS_BLOCK_SKIP;
 472         info->free_list = (void**)obj_start;
 473         /* we're skipping the last one - it must be nulled */
 474         for (i = 0; i < count - 1; ++i) {
 475                 char *next_obj_start = obj_start + size;
 476                 *(void**)obj_start = next_obj_start;
 477                 obj_start = next_obj_start;
 478         }
 479         /* the last one */
 480         *(void**)obj_start = NULL;
 481
 482         info->next_free = free_blocks [size_index];
 483         free_blocks [size_index] = info;
 484
 485         sgen_pointer_queue_add (&allocated_blocks, BLOCK_TAG (info));
 486
 487         ++num_major_sections;
 488         return TRUE;
 489 }
 490
 491 static gboolean
 492 obj_is_from_pinned_alloc (char *ptr)
 493 {
 494         MSBlockInfo *block;
 495
 496         FOREACH_BLOCK (block) {
 497                 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE)
 498                         return block->pinned;
 499         } END_FOREACH_BLOCK;
 500         return FALSE;
 501 }
 502
 503 static void*
 504 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
 505 {
 506         MSBlockInfo *block;
 507         void *obj;
 508
 509         block = free_blocks [size_index];
 510         SGEN_ASSERT (9, block, "no free block to unlink from free_blocks %p size_index %d", free_blocks, size_index);
 511
 512         if (G_UNLIKELY (!block->swept)) {
 513                 stat_major_blocks_lazy_swept ++;
 514                 sweep_block (block, FALSE);
 515         }
 516
 517         obj = block->free_list;
 518         SGEN_ASSERT (9, obj, "block %p in free list had no available object to alloc from", block);
 519
 520         block->free_list = *(void**)obj;
 521         if (!block->free_list) {
 522                 free_blocks [size_index] = block->next_free;
 523                 block->next_free = NULL;
 524         }
 525
 526         return obj;
 527 }
 528
 529 static void*
 530 alloc_obj (MonoVTable *vtable, size_t size, gboolean pinned, gboolean has_references)
 531 {
 532         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 533         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 534         void *obj;
 535
 536         if (!free_blocks [size_index]) {
 537                 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
 538                         return NULL;
 539         }
 540
 541         obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
 542
 543         *(MonoVTable**)obj = vtable;
 544
 545         return obj;
 546 }
 547
 548 static void*
 549 major_alloc_object (MonoVTable *vtable, size_t size, gboolean has_references)
 550 {
 551         return alloc_obj (vtable, size, FALSE, has_references);
 552 }
 553
 554 /*
 555  * We're not freeing the block if it's empty.  We leave that work for
 556  * the next major collection.
 557  *
 558  * This is just called from the domain clearing code, which runs in a
 559  * single thread and has the GC lock, so we don't need an extra lock.
 560  */
 561 static void
 562 free_object (char *obj, size_t size, gboolean pinned)
 563 {
 564         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 565         int word, bit;
 566
 567         if (!block->swept)
 568                 sweep_block (block, FALSE);
 569         SGEN_ASSERT (9, (pinned && block->pinned) || (!pinned && !block->pinned), "free-object pinning mixup object %p pinned %d block %p pinned %d", obj, pinned, block, block->pinned);
 570         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p is already free", obj);
 571         MS_CALC_MARK_BIT (word, bit, obj);
 572         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p has mark bit set");
 573         if (!block->free_list) {
 574                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
 575                 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 576                 SGEN_ASSERT (9, !block->next_free, "block %p doesn't have a free-list of object but belongs to a free-list of blocks");
 577                 block->next_free = free_blocks [size_index];
 578                 free_blocks [size_index] = block;
 579         }
 580         memset (obj, 0, size);
 581         *(void**)obj = block->free_list;
 582         block->free_list = (void**)obj;
 583 }
 584
 585 static void
 586 major_free_non_pinned_object (char *obj, size_t size)
 587 {
 588         free_object (obj, size, FALSE);
 589 }
 590
 591 /* size is a multiple of SGEN_ALLOC_ALIGN */
 592 static void*
 593 major_alloc_small_pinned_obj (MonoVTable *vtable, size_t size, gboolean has_references)
 594 {
 595         void *res;
 596
 597         res = alloc_obj (vtable, size, TRUE, has_references);
 598          /*If we failed to alloc memory, we better try releasing memory
 599           *as pinned alloc is requested by the runtime.
 600           */
 601          if (!res) {
 602                 sgen_perform_collection (0, GENERATION_OLD, "pinned alloc failure", TRUE);
 603                 res = alloc_obj (vtable, size, TRUE, has_references);
 604          }
 605          return res;
 606 }
 607
 608 static void
 609 free_pinned_object (char *obj, size_t size)
 610 {
 611         free_object (obj, size, TRUE);
 612 }
 613
 614 /*
 615  * size is already rounded up and we hold the GC lock.
 616  */
 617 static void*
 618 major_alloc_degraded (MonoVTable *vtable, size_t size)
 619 {
 620         void *obj;
 621         size_t old_num_sections;
 622
 623         old_num_sections = num_major_sections;
 624
 625         obj = alloc_obj (vtable, size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
 626         if (G_LIKELY (obj)) {
 627                 HEAVY_STAT (++stat_objects_alloced_degraded);
 628                 HEAVY_STAT (stat_bytes_alloced_degraded += size);
 629                 g_assert (num_major_sections >= old_num_sections);
 630                 sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
 631         }
 632         return obj;
 633 }
 634
 635 /*
 636  * obj is some object.  If it's not in the major heap (i.e. if it's in
 637  * the nursery or LOS), return FALSE.  Otherwise return whether it's
 638  * been marked or copied.
 639  */
 640 static gboolean
 641 major_is_object_live (char *obj)
 642 {
 643         MSBlockInfo *block;
 644         int word, bit;
 645         mword objsize;
 646
 647         if (sgen_ptr_in_nursery (obj))
 648                 return FALSE;
 649
 650         objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 651
 652         /* LOS */
 653         if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
 654                 return FALSE;
 655
 656         /* now we know it's in a major block */
 657         block = MS_BLOCK_FOR_OBJ (obj);
 658         SGEN_ASSERT (9, !block->pinned, "block %p is pinned, BTW why is this bad?");
 659         MS_CALC_MARK_BIT (word, bit, obj);
 660         return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
 661 }
 662
 663 static gboolean
 664 major_ptr_is_in_non_pinned_space (char *ptr, char **start)
 665 {
 666         MSBlockInfo *block;
 667
 668         FOREACH_BLOCK (block) {
 669                 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) {
 670                         int count = MS_BLOCK_FREE / block->obj_size;
 671                         int i;
 672
 673                         *start = NULL;
 674                         for (i = 0; i <= count; ++i) {
 675                                 if (ptr >= MS_BLOCK_OBJ (block, i) && ptr < MS_BLOCK_OBJ (block, i + 1)) {
 676                                         *start = MS_BLOCK_OBJ (block, i);
 677                                         break;
 678                                 }
 679                         }
 680                         return !block->pinned;
 681                 }
 682         } END_FOREACH_BLOCK;
 683         return FALSE;
 684 }
 685
 686 static void
 687 major_iterate_objects (IterateObjectsFlags flags, IterateObjectCallbackFunc callback, void *data)
 688 {
 689         gboolean sweep = flags & ITERATE_OBJECTS_SWEEP;
 690         gboolean non_pinned = flags & ITERATE_OBJECTS_NON_PINNED;
 691         gboolean pinned = flags & ITERATE_OBJECTS_PINNED;
 692         MSBlockInfo *block;
 693
 694         FOREACH_BLOCK (block) {
 695                 int count = MS_BLOCK_FREE / block->obj_size;
 696                 int i;
 697
 698                 if (block->pinned && !pinned)
 699                         continue;
 700                 if (!block->pinned && !non_pinned)
 701                         continue;
 702                 if (sweep && lazy_sweep) {
 703                         sweep_block (block, FALSE);
 704                         SGEN_ASSERT (0, block->swept, "Block must be swept after sweeping");
 705                 }
 706
 707                 for (i = 0; i < count; ++i) {
 708                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 709                         if (!block->swept) {
 710                                 int word, bit;
 711                                 MS_CALC_MARK_BIT (word, bit, obj);
 712                                 if (!MS_MARK_BIT (block, word, bit))
 713                                         continue;
 714                         }
 715                         if (MS_OBJ_ALLOCED (obj, block))
 716                                 callback ((char*)obj, block->obj_size, data);
 717                 }
 718         } END_FOREACH_BLOCK;
 719 }
 720
 721 static gboolean
 722 major_is_valid_object (char *object)
 723 {
 724         MSBlockInfo *block;
 725
 726         FOREACH_BLOCK (block) {
 727                 int idx;
 728                 char *obj;
 729
 730                 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > object) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= object))
 731                         continue;
 732
 733                 idx = MS_BLOCK_OBJ_INDEX (object, block);
 734                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 735                 if (obj != object)
 736                         return FALSE;
 737                 return MS_OBJ_ALLOCED (obj, block);
 738         } END_FOREACH_BLOCK;
 739
 740         return FALSE;
 741 }
 742
 743
 744 static MonoVTable*
 745 major_describe_pointer (char *ptr)
 746 {
 747         MSBlockInfo *block;
 748
 749         FOREACH_BLOCK (block) {
 750                 int idx;
 751                 char *obj;
 752                 gboolean live;
 753                 MonoVTable *vtable;
 754                 int w, b;
 755                 gboolean marked;
 756
 757                 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > ptr) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= ptr))
 758                         continue;
 759
 760                 SGEN_LOG (0, "major-ptr (block %p sz %d pin %d ref %d)\n",
 761                         MS_BLOCK_FOR_BLOCK_INFO (block), block->obj_size, block->pinned, block->has_references);
 762
 763                 idx = MS_BLOCK_OBJ_INDEX (ptr, block);
 764                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 765                 live = MS_OBJ_ALLOCED (obj, block);
 766                 vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
 767
 768                 MS_CALC_MARK_BIT (w, b, obj);
 769                 marked = MS_MARK_BIT (block, w, b);
 770
 771                 if (obj == ptr) {
 772                         SGEN_LOG (0, "\t(");
 773                         if (live)
 774                                 SGEN_LOG (0, "object");
 775                         else
 776                                 SGEN_LOG (0, "dead-object");
 777                 } else {
 778                         if (live)
 779                                 SGEN_LOG (0, "interior-ptr offset %td", ptr - obj);
 780                         else
 781                                 SGEN_LOG (0, "dead-interior-ptr offset %td", ptr - obj);
 782                 }
 783
 784                 SGEN_LOG (0, " marked %d)\n", marked ? 1 : 0);
 785
 786                 return vtable;
 787         } END_FOREACH_BLOCK;
 788
 789         return NULL;
 790 }
 791
 792 static void
 793 major_check_scan_starts (void)
 794 {
 795 }
 796
 797 static void
 798 major_dump_heap (FILE *heap_dump_file)
 799 {
 800         MSBlockInfo *block;
 801         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
 802         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
 803         int i;
 804
 805         for (i = 0; i < num_block_obj_sizes; ++i)
 806                 slots_available [i] = slots_used [i] = 0;
 807
 808         FOREACH_BLOCK (block) {
 809                 int index = ms_find_block_obj_size_index (block->obj_size);
 810                 int count = MS_BLOCK_FREE / block->obj_size;
 811
 812                 slots_available [index] += count;
 813                 for (i = 0; i < count; ++i) {
 814                         if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
 815                                 ++slots_used [index];
 816                 }
 817         } END_FOREACH_BLOCK;
 818
 819         fprintf (heap_dump_file, "<occupancies>\n");
 820         for (i = 0; i < num_block_obj_sizes; ++i) {
 821                 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
 822                                 block_obj_sizes [i], slots_available [i], slots_used [i]);
 823         }
 824         fprintf (heap_dump_file, "</occupancies>\n");
 825
 826         FOREACH_BLOCK (block) {
 827                 int count = MS_BLOCK_FREE / block->obj_size;
 828                 int i;
 829                 int start = -1;
 830
 831                 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
 832
 833                 for (i = 0; i <= count; ++i) {
 834                         if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
 835                                 if (start < 0)
 836                                         start = i;
 837                         } else {
 838                                 if (start >= 0) {
 839                                         sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), MS_BLOCK_FOR_BLOCK_INFO (block));
 840                                         start = -1;
 841                                 }
 842                         }
 843                 }
 844
 845                 fprintf (heap_dump_file, "</section>\n");
 846         } END_FOREACH_BLOCK;
 847 }
 848
 849 #define LOAD_VTABLE     SGEN_LOAD_VTABLE
 850
 851 #ifdef SGEN_MARK_ON_ENQUEUE
 852 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,desc,block,queue) do {   \
 853                 int __word, __bit;                                      \
 854                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 855                 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
 856                         MS_SET_MARK_BIT ((block), __word, __bit);       \
 857                         if ((block)->has_references)                    \
 858                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 859                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 860                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 861                 }                                                       \
 862         } while (0)
 863 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do {           \
 864                 int __word, __bit;                                      \
 865                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 866                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj); \
 867                 if (!MS_MARK_BIT ((block), __word, __bit)) {            \
 868                         MS_SET_MARK_BIT ((block), __word, __bit);       \
 869                         if ((block)->has_references)                    \
 870                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 871                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 872                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 873                 }                                                       \
 874         } while (0)
 875 #define MS_PAR_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do {       \
 876                 int __word, __bit;                                      \
 877                 gboolean __was_marked;                                  \
 878                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj); \
 879                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 880                 MS_PAR_SET_MARK_BIT (__was_marked, (block), __word, __bit); \
 881                 if (!__was_marked) {                                    \
 882                         if ((block)->has_references)                    \
 883                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 884                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 885                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 886                 }                                                       \
 887         } while (0)
 888 #else
 889 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,desc,block,queue) do {   \
 890                 int __word, __bit;                                      \
 891                 SGEN_ASSERT (0, sgen_get_current_collection_generation () == GENERATION_OLD, "Can't majorly enqueue objects when doing minor collection"); \
 892                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 893                 if (MS_OBJ_ALLOCED ((obj), (block))) { \
 894                         if ((block)->has_references) {                  \
 895                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 896                         } else {                                        \
 897                                 MS_SET_MARK_BIT ((block), __word, __bit); \
 898                                 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 899                         }                                               \
 900                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 901                 }                                                       \
 902         } while (0)
 903 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do {           \
 904                 int __word, __bit;                                      \
 905                 SGEN_ASSERT (0, sgen_get_current_collection_generation () == GENERATION_OLD, "Can't majorly enqueue objects when doing minor collection"); \
 906                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 907                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj);       \
 908                 {               \
 909                         if ((block)->has_references) {                  \
 910                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 911                         } else {                                        \
 912                                 MS_SET_MARK_BIT ((block), __word, __bit); \
 913                                 binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 914                         }                                               \
 915                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 916                 }                                                       \
 917         } while (0)
 918 #endif
 919
 920 static void
 921 pin_major_object (char *obj, SgenGrayQueue *queue)
 922 {
 923         MSBlockInfo *block;
 924
 925 #ifdef SGEN_HAVE_CONCURRENT_MARK
 926         if (concurrent_mark)
 927                 g_assert_not_reached ();
 928 #endif
 929
 930         block = MS_BLOCK_FOR_OBJ (obj);
 931         block->has_pinned = TRUE;
 932         MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 933 }
 934
 935 #include "sgen-major-copy-object.h"
 936
 937 #ifdef SGEN_HAVE_CONCURRENT_MARK
 938 static void
 939 major_copy_or_mark_object_concurrent (void **ptr, void *obj, SgenGrayQueue *queue)
 940 {
 941         SGEN_ASSERT (9, sgen_concurrent_collection_in_progress (), "Why are we scanning concurrently when there's no concurrent collection on?");
 942         SGEN_ASSERT (9, !sgen_workers_are_working () || sgen_is_worker_thread (mono_native_thread_id_get ()), "We must not scan from two threads at the same time!");
 943
 944         g_assert (!SGEN_OBJECT_IS_FORWARDED (obj));
 945
 946         if (!sgen_ptr_in_nursery (obj)) {
 947                 mword objsize;
 948
 949                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 950
 951                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
 952                         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 953                         MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 954                 } else {
 955                         if (sgen_los_object_is_pinned (obj))
 956                                 return;
 957
 958 #ifdef ENABLE_DTRACE
 959                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
 960                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
 961                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
 962                         }
 963 #endif
 964
 965                         sgen_los_pin_object (obj);
 966                         if (SGEN_OBJECT_HAS_REFERENCES (obj))
 967                                 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
 968                         INC_NUM_MAJOR_OBJECTS_MARKED ();
 969                 }
 970         }
 971 }
 972 #endif
 973
 974 static void
 975 major_copy_or_mark_object (void **ptr, void *obj, SgenGrayQueue *queue)
 976 {
 977         MSBlockInfo *block;
 978
 979         HEAVY_STAT (++stat_copy_object_called_major);
 980
 981         SGEN_ASSERT (9, !sgen_concurrent_collection_in_progress (), "Why are we scanning non-concurrently when there's a concurrent collection on?");
 982
 983         SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
 984         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
 985
 986         if (sgen_ptr_in_nursery (obj)) {
 987                 int word, bit;
 988                 char *forwarded, *old_obj;
 989
 990                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
 991                         SGEN_UPDATE_REFERENCE (ptr, forwarded);
 992                         return;
 993                 }
 994                 if (SGEN_OBJECT_IS_PINNED (obj))
 995                         return;
 996
 997                 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
 998                 if (sgen_nursery_is_to_space (obj))
 999                         return;
1000
1001                 HEAVY_STAT (++stat_objects_copied_major);
1002
1003         do_copy_object:
1004                 old_obj = obj;
1005                 obj = copy_object_no_checks (obj, queue);
1006                 if (G_UNLIKELY (old_obj == obj)) {
1007                         /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
1008                         if (!sgen_ptr_in_nursery (obj)) {
1009                                 int size_index;
1010                                 block = MS_BLOCK_FOR_OBJ (obj);
1011                                 size_index = block->obj_size_index;
1012                                 evacuate_block_obj_sizes [size_index] = FALSE;
1013                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
1014                         }
1015                         return;
1016                 }
1017                 SGEN_UPDATE_REFERENCE (ptr, obj);
1018
1019                 /*
1020                  * FIXME: See comment for copy_object_no_checks().  If
1021                  * we have that, we can let the allocation function
1022                  * give us the block info, too, and we won't have to
1023                  * re-fetch it.
1024                  *
1025                  * FIXME (2): We should rework this to avoid all those nursery checks.
1026                  */
1027                 /*
1028                  * For the split nursery allocator the object might
1029                  * still be in the nursery despite having being
1030                  * promoted, in which case we can't mark it.
1031                  */
1032                 if (!sgen_ptr_in_nursery (obj)) {
1033                         block = MS_BLOCK_FOR_OBJ (obj);
1034                         MS_CALC_MARK_BIT (word, bit, obj);
1035                         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
1036 #ifndef SGEN_MARK_ON_ENQUEUE
1037                         if (!SGEN_VTABLE_HAS_REFERENCES (LOAD_VTABLE (obj)))
1038 #endif
1039                         {
1040                                 MS_SET_MARK_BIT (block, word, bit);
1041                                 binary_protocol_mark (obj, (gpointer)LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1042                         }
1043                 }
1044         } else {
1045                 char *forwarded;
1046                 mword objsize;
1047
1048                 /*
1049                  * If we have don't have a fixed heap we cannot know
1050                  * whether an object is in the LOS or in the small
1051                  * object major heap without checking its size.  To do
1052                  * that, however, we need to know that we actually
1053                  * have a valid object, not a forwarding pointer, so
1054                  * we have to do this check first.
1055                  */
1056                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1057                         SGEN_UPDATE_REFERENCE (ptr, forwarded);
1058                         return;
1059                 }
1060
1061                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
1062
1063                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
1064                         int size_index;
1065                         gboolean evacuate;
1066
1067                         block = MS_BLOCK_FOR_OBJ (obj);
1068                         size_index = block->obj_size_index;
1069                         evacuate = evacuate_block_obj_sizes [size_index];
1070
1071                         if (evacuate && !block->has_pinned) {
1072                                 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1073                                 if (block->is_to_space)
1074                                         return;
1075                                 HEAVY_STAT (++stat_major_objects_evacuated);
1076                                 goto do_copy_object;
1077                         } else {
1078                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
1079                         }
1080                 } else {
1081                         if (sgen_los_object_is_pinned (obj))
1082                                 return;
1083                         binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1084
1085 #ifdef ENABLE_DTRACE
1086                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1087                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
1088                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
1089                         }
1090 #endif
1091
1092 #ifdef SGEN_MARK_ON_ENQUEUE
1093                         sgen_los_pin_object (obj);
1094 #endif
1095                         if (SGEN_OBJECT_HAS_REFERENCES (obj))
1096                                 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
1097                 }
1098         }
1099 }
1100
1101 static void
1102 major_copy_or_mark_object_canonical (void **ptr, SgenGrayQueue *queue)
1103 {
1104         major_copy_or_mark_object (ptr, *ptr, queue);
1105 }
1106
1107 #ifdef SGEN_HAVE_CONCURRENT_MARK
1108 static void
1109 major_copy_or_mark_object_concurrent_canonical (void **ptr, SgenGrayQueue *queue)
1110 {
1111         major_copy_or_mark_object_concurrent (ptr, *ptr, queue);
1112 }
1113 #endif
1114
1115 static long long
1116 major_get_and_reset_num_major_objects_marked (void)
1117 {
1118 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
1119         long long num = num_major_objects_marked;
1120         num_major_objects_marked = 0;
1121         return num;
1122 #else
1123         return 0;
1124 #endif
1125 }
1126
1127 #include "sgen-major-scan-object.h"
1128
1129 #ifdef SGEN_HAVE_CONCURRENT_MARK
1130 #define SCAN_FOR_CONCURRENT_MARK
1131 #include "sgen-major-scan-object.h"
1132 #undef SCAN_FOR_CONCURRENT_MARK
1133 #endif
1134
1135 #if !defined (FIXED_HEAP) && !defined (SGEN_PARALLEL_MARK)
1136 //#define USE_PREFETCH_QUEUE
1137 #define DESCRIPTOR_FAST_PATH
1138
1139 #ifdef HEAVY_STATISTICS
1140 static long long stat_optimized_copy;
1141 static long long stat_optimized_copy_nursery;
1142 static long long stat_optimized_copy_nursery_forwarded;
1143 static long long stat_optimized_copy_nursery_pinned;
1144 #ifdef SGEN_MARK_ON_ENQUEUE
1145 static long long stat_optimized_copy_major;
1146 static long long stat_optimized_copy_major_small_fast;
1147 static long long stat_optimized_copy_major_small_slow;
1148 static long long stat_optimized_copy_major_large;
1149 #endif
1150 static long long stat_optimized_major_mark;
1151 static long long stat_optimized_major_mark_small;
1152 static long long stat_optimized_major_mark_large;
1153 static long long stat_optimized_major_scan;
1154 static long long stat_optimized_major_scan_no_refs;
1155 #ifdef DESCRIPTOR_FAST_PATH
1156 static long long stat_optimized_major_scan_fast;
1157 static long long stat_optimized_major_scan_slow;
1158 #endif
1159
1160 static long long stat_drain_prefetch_fills;
1161 static long long stat_drain_prefetch_fill_failures;
1162 static long long stat_drain_loops;
1163 #endif
1164
1165 /* Returns whether the object is still in the nursery. */
1166 static gboolean
1167 optimized_copy_or_mark_object (void **ptr, void *obj, SgenGrayQueue *queue)
1168 {
1169 #ifdef SGEN_MARK_ON_ENQUEUE
1170         MSBlockInfo *block;
1171 #endif
1172
1173 #ifdef HEAVY_STATISTICS
1174         ++stat_optimized_copy;
1175         {
1176                 char *forwarded;
1177                 mword desc;
1178                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj)))
1179                         desc = sgen_obj_get_descriptor_safe (forwarded);
1180                 else
1181                         desc = sgen_obj_get_descriptor_safe (obj);
1182
1183                 sgen_descriptor_count_copied_object (desc);
1184         }
1185 #endif
1186
1187         SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
1188         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
1189
1190         if (sgen_ptr_in_nursery (obj)) {
1191 #ifdef SGEN_MARK_ON_ENQUEUE
1192                 int word, bit;
1193 #endif
1194                 char *forwarded, *old_obj;
1195                 mword vtable_word = *(mword*)obj;
1196
1197                 HEAVY_STAT (++stat_optimized_copy_nursery);
1198
1199                 if (SGEN_VTABLE_IS_PINNED (vtable_word)) {
1200                         HEAVY_STAT (++stat_optimized_copy_nursery_pinned);
1201                         return TRUE;
1202                 }
1203                 if ((forwarded = SGEN_VTABLE_IS_FORWARDED (vtable_word))) {
1204                         HEAVY_STAT (++stat_optimized_copy_nursery_forwarded);
1205                         *ptr = forwarded;
1206                         return FALSE;
1207                 }
1208
1209                 old_obj = obj;
1210                 obj = copy_object_no_checks (obj, queue);
1211                 SGEN_ASSERT (0, old_obj != obj, "Cannot handle copy object failure.");
1212                 HEAVY_STAT (++stat_objects_copied_major);
1213                 *ptr = obj;
1214
1215 #ifdef SGEN_MARK_ON_ENQUEUE
1216                 /*
1217                  * FIXME: See comment for copy_object_no_checks().  If
1218                  * we have that, we can let the allocation function
1219                  * give us the block info, too, and we won't have to
1220                  * re-fetch it.
1221                  *
1222                  * FIXME (2): We should rework this to avoid all those nursery checks.
1223                  */
1224                 /*
1225                  * For the split nursery allocator the object might
1226                  * still be in the nursery despite having being
1227                  * promoted, in which case we can't mark it.
1228                  */
1229                 block = MS_BLOCK_FOR_OBJ (obj);
1230                 MS_CALC_MARK_BIT (word, bit, obj);
1231                 SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
1232                 MS_SET_MARK_BIT (block, word, bit);
1233                 binary_protocol_mark (obj, (gpointer)LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1234 #endif
1235
1236                 return FALSE;
1237         } else {
1238 #ifdef SGEN_MARK_ON_ENQUEUE
1239                 mword vtable_word = *(mword*)obj;
1240                 mword desc = sgen_vtable_get_descriptor ((MonoVTable*)vtable_word);
1241                 int type = desc & 7;
1242
1243                 HEAVY_STAT (++stat_optimized_copy_major);
1244
1245                 if (type == DESC_TYPE_SMALL_BITMAP || type == DESC_TYPE_RUN_LENGTH) {
1246                         int __word, __bit;
1247
1248                         HEAVY_STAT (++stat_optimized_copy_major_small_fast);
1249
1250                         block = MS_BLOCK_FOR_OBJ (obj);
1251                         MS_CALC_MARK_BIT (__word, __bit, (obj));
1252                         if (!MS_MARK_BIT ((block), __word, __bit)) {
1253                                 MS_SET_MARK_BIT ((block), __word, __bit);
1254                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc));
1255                         }
1256                 } else if (SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj)) <= SGEN_MAX_SMALL_OBJ_SIZE ) {
1257                         HEAVY_STAT (++stat_optimized_copy_major_small_slow);
1258
1259                         block = MS_BLOCK_FOR_OBJ (obj);
1260                         MS_MARK_OBJECT_AND_ENQUEUE (obj, desc, block, queue);
1261                 } else {
1262                         HEAVY_STAT (++stat_optimized_copy_major_large);
1263
1264                         if (sgen_los_object_is_pinned (obj))
1265                                 return FALSE;
1266                         binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1267
1268                         sgen_los_pin_object (obj);
1269                         if (SGEN_OBJECT_HAS_REFERENCES (obj))
1270                                 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
1271                 }
1272                 return FALSE;
1273 #else
1274                 GRAY_OBJECT_ENQUEUE (queue, obj, 0);
1275 #endif
1276         }
1277         return FALSE;
1278 }
1279
1280 static inline void
1281 sgen_gray_object_dequeue_fast (SgenGrayQueue *queue, char** obj, mword *desc) {
1282         GrayQueueEntry *cursor = queue->prefetch_cursor;
1283         GrayQueueEntry *const end = queue->prefetch + SGEN_GRAY_QUEUE_PREFETCH_SIZE;
1284         *obj = cursor->obj;
1285 #ifdef SGEN_GRAY_QUEUE_HAVE_DESCRIPTORS
1286         *desc = cursor->desc;
1287         GRAY_OBJECT_DEQUEUE (queue, &cursor->obj, &cursor->desc);
1288 #else
1289         GRAY_OBJECT_DEQUEUE (queue, &cursor->obj, NULL);
1290 #endif
1291
1292 #if !defined (SGEN_MARK_ON_ENQUEUE) && defined (BLOCK_INFO_IN_HEADER)
1293         {
1294                 int word, bit;
1295                 MSBlockInfo *block = (MSBlockInfo*)MS_BLOCK_DATA_FOR_OBJ (cursor->obj);
1296                 MS_CALC_MARK_BIT (word, bit, cursor->obj);
1297                 PREFETCH_WRITE (&block->mark_words [word]);
1298         }
1299 #endif
1300
1301         PREFETCH_READ (cursor->obj);
1302         ++cursor;
1303         if (cursor == end)
1304                 cursor = queue->prefetch;
1305         queue->prefetch_cursor = cursor;
1306 }
1307
1308 static gboolean
1309 drain_gray_stack (ScanCopyContext ctx)
1310 {
1311         SgenGrayQueue *queue = ctx.queue;
1312
1313         SGEN_ASSERT (0, ctx.scan_func == major_scan_object, "Wrong scan function");
1314
1315 #ifdef USE_PREFETCH_QUEUE
1316         HEAVY_STAT (++stat_drain_prefetch_fills);
1317         if (!sgen_gray_object_fill_prefetch (queue)) {
1318                 HEAVY_STAT (++stat_drain_prefetch_fill_failures);
1319                 return TRUE;
1320         }
1321 #endif
1322
1323         for (;;) {
1324                 char *obj;
1325                 mword desc;
1326                 int type;
1327
1328                 HEAVY_STAT (++stat_drain_loops);
1329
1330 #ifdef USE_PREFETCH_QUEUE
1331                 sgen_gray_object_dequeue_fast (queue, &obj, &desc);
1332                 if (!obj) {
1333                         HEAVY_STAT (++stat_drain_prefetch_fills);
1334                         if (!sgen_gray_object_fill_prefetch (queue)) {
1335                                 HEAVY_STAT (++stat_drain_prefetch_fill_failures);
1336                                 return TRUE;
1337                         }
1338                         continue;
1339                 }
1340 #else
1341                 GRAY_OBJECT_DEQUEUE (queue, &obj, &desc);
1342                 if (!obj)
1343                         return TRUE;
1344 #endif
1345
1346 #ifndef SGEN_GRAY_QUEUE_HAVE_DESCRIPTORS
1347                 desc = sgen_obj_get_descriptor_safe (obj);
1348 #endif
1349                 type = desc & 7;
1350
1351 #ifndef SGEN_MARK_ON_ENQUEUE
1352                 HEAVY_STAT (++stat_optimized_major_mark);
1353
1354                 /* Mark object or, if already marked, don't process. */
1355                 if (!sgen_ptr_in_nursery (obj)) {
1356                         if (type == DESC_TYPE_SMALL_BITMAP || SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj)) <= SGEN_MAX_SMALL_OBJ_SIZE) {
1357                                 MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1358                                 int __word, __bit;
1359
1360                                 HEAVY_STAT (++stat_optimized_major_mark_small);
1361
1362                                 MS_CALC_MARK_BIT (__word, __bit, (obj));
1363                                 if (MS_MARK_BIT ((block), __word, __bit))
1364                                         continue;
1365                                 MS_SET_MARK_BIT ((block), __word, __bit);
1366                         } else {
1367                                 HEAVY_STAT (++stat_optimized_major_mark_large);
1368
1369                                 if (sgen_los_object_is_pinned (obj))
1370                                         continue;
1371                                 sgen_los_pin_object (obj);
1372                         }
1373                 }
1374 #endif
1375
1376 #ifdef HEAVY_STATISTICS
1377                 ++stat_optimized_major_scan;
1378                 if (!sgen_gc_descr_has_references (desc))
1379                         ++stat_optimized_major_scan_no_refs;
1380 #endif
1381
1382                 /* Now scan the object. */
1383
1384 #undef HANDLE_PTR
1385 #define HANDLE_PTR(ptr,obj)     do {                                    \
1386                         void *__old = *(ptr);                           \
1387                         if (__old) {                                    \
1388                                 gboolean __still_in_nursery = optimized_copy_or_mark_object ((ptr), __old, queue); \
1389                                 if (G_UNLIKELY (__still_in_nursery && !sgen_ptr_in_nursery ((ptr)) && !SGEN_OBJECT_IS_CEMENTED (*(ptr)))) { \
1390                                         void *__copy = *(ptr);          \
1391                                         sgen_add_to_global_remset ((ptr), __copy); \
1392                                 }                                       \
1393                         }                                               \
1394                 } while (0)
1395
1396 #ifdef DESCRIPTOR_FAST_PATH
1397                 if (type == DESC_TYPE_SMALL_BITMAP) {
1398                         void **_objptr = (void**)(obj);
1399                         gsize _bmap = (desc) >> 16;
1400                         _objptr += OBJECT_HEADER_WORDS;
1401                         do {
1402                                 int _index = GNUC_BUILTIN_CTZ (_bmap);
1403                                 _objptr += _index;
1404                                 _bmap >>= (_index + 1);
1405                                 HANDLE_PTR (_objptr, NULL);
1406                                 _objptr ++;
1407                         } while (_bmap);
1408 #ifdef HEAVY_STATISTICS
1409                         sgen_descriptor_count_scanned_object (desc);
1410                         ++stat_optimized_major_scan_fast;
1411 #endif
1412 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
1413                         add_scanned_object (obj);
1414 #endif
1415                 } else {
1416                         HEAVY_STAT (++stat_optimized_major_scan_slow);
1417                         major_scan_object_no_mark (obj, desc, queue);
1418                 }
1419 #else
1420                 {
1421                         char *start = obj;
1422 #ifdef HEAVY_STATISTICS
1423                         sgen_descriptor_count_scanned_object (desc);
1424                         add_scanned_object (start);
1425 #endif
1426
1427 #include "sgen-scan-object.h"
1428                 }
1429 #endif
1430         }
1431 }
1432 #endif
1433
1434 static void
1435 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
1436 {
1437         void **entry, **end;
1438         int last_index = -1;
1439
1440         if (block->pin_queue_first_entry == block->pin_queue_last_entry)
1441                 return;
1442
1443         block->has_pinned = TRUE;
1444
1445         entry = sgen_pinning_get_entry (block->pin_queue_first_entry);
1446         end = sgen_pinning_get_entry (block->pin_queue_last_entry);
1447
1448         for (; entry < end; ++entry) {
1449                 int index = MS_BLOCK_OBJ_INDEX (*entry, block);
1450                 char *obj;
1451                 SGEN_ASSERT (9, index >= 0 && index < MS_BLOCK_FREE / block->obj_size, "invalid object %p index %d max-index %d", *entry, index, MS_BLOCK_FREE / block->obj_size);
1452                 if (index == last_index)
1453                         continue;
1454                 obj = MS_BLOCK_OBJ (block, index);
1455                 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (obj, sgen_obj_get_descriptor (obj), block, queue);
1456                 last_index = index;
1457         }
1458 }
1459
1460 static inline void
1461 sweep_block_for_size (MSBlockInfo *block, int count, int obj_size)
1462 {
1463         int obj_index;
1464
1465         for (obj_index = 0; obj_index < count; ++obj_index) {
1466                 int word, bit;
1467                 void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, obj_index, obj_size);
1468
1469                 MS_CALC_MARK_BIT (word, bit, obj);
1470                 if (MS_MARK_BIT (block, word, bit)) {
1471                         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p not allocated", obj);
1472                 } else {
1473                         /* an unmarked object */
1474                         if (MS_OBJ_ALLOCED (obj, block)) {
1475                                 /*
1476                                  * FIXME: Merge consecutive
1477                                  * slots for lower reporting
1478                                  * overhead.  Maybe memset
1479                                  * will also benefit?
1480                                  */
1481                                 binary_protocol_empty (obj, obj_size);
1482                                 MONO_GC_MAJOR_SWEPT ((mword)obj, obj_size);
1483                                 memset (obj, 0, obj_size);
1484                         }
1485                         *(void**)obj = block->free_list;
1486                         block->free_list = obj;
1487                 }
1488         }
1489 }
1490
1491 /*
1492  * sweep_block:
1493  *
1494  *   Traverse BLOCK, freeing and zeroing unused objects.
1495  */
1496 static void
1497 sweep_block (MSBlockInfo *block, gboolean during_major_collection)
1498 {
1499         int count;
1500         void *reversed = NULL;
1501
1502         if (!during_major_collection)
1503                 g_assert (!sgen_concurrent_collection_in_progress ());
1504
1505         if (block->swept)
1506                 return;
1507
1508         count = MS_BLOCK_FREE / block->obj_size;
1509
1510         block->free_list = NULL;
1511
1512         /* Use inline instances specialized to constant sizes, this allows the compiler to replace the memset calls with inline code */
1513         // FIXME: Add more sizes
1514         switch (block->obj_size) {
1515         case 16:
1516                 sweep_block_for_size (block, count, 16);
1517                 break;
1518         default:
1519                 sweep_block_for_size (block, count, block->obj_size);
1520                 break;
1521         }
1522
1523         /* reset mark bits */
1524         memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1525
1526         /* Reverse free list so that it's in address order */
1527         reversed = NULL;
1528         while (block->free_list) {
1529                 void *next = *(void**)block->free_list;
1530                 *(void**)block->free_list = reversed;
1531                 reversed = block->free_list;
1532                 block->free_list = next;
1533         }
1534         block->free_list = reversed;
1535
1536         block->swept = 1;
1537 }
1538
1539 static inline int
1540 bitcount (mword d)
1541 {
1542         int count = 0;
1543
1544 #ifdef __GNUC__
1545         if (sizeof (mword) == sizeof (unsigned long))
1546                 count += __builtin_popcountl (d);
1547         else
1548                 count += __builtin_popcount (d);
1549 #else
1550         while (d) {
1551                 count ++;
1552                 d &= (d - 1);
1553         }
1554 #endif
1555         return count;
1556 }
1557
1558 static void
1559 ms_sweep (void)
1560 {
1561         int i;
1562         MSBlockInfo *block;
1563
1564         /* statistics for evacuation */
1565         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1566         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1567         int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1568
1569 #ifdef SGEN_HAVE_CONCURRENT_MARK
1570         mword total_evacuate_heap = 0;
1571         mword total_evacuate_saved = 0;
1572 #endif
1573
1574         for (i = 0; i < num_block_obj_sizes; ++i)
1575                 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1576
1577         /* clear all the free lists */
1578         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1579                 MSBlockInfo **free_blocks = free_block_lists [i];
1580                 int j;
1581                 for (j = 0; j < num_block_obj_sizes; ++j)
1582                         free_blocks [j] = NULL;
1583         }
1584
1585         /* traverse all blocks, free and zero unmarked objects */
1586         FOREACH_BLOCK (block) {
1587                 int count;
1588                 gboolean have_live = FALSE;
1589                 gboolean has_pinned;
1590                 gboolean have_free = FALSE;
1591                 int obj_size_index;
1592                 int nused = 0;
1593
1594                 obj_size_index = block->obj_size_index;
1595
1596                 has_pinned = block->has_pinned;
1597                 block->has_pinned = block->pinned;
1598
1599                 block->is_to_space = FALSE;
1600                 block->swept = 0;
1601
1602                 count = MS_BLOCK_FREE / block->obj_size;
1603
1604 #ifdef SGEN_HAVE_CONCURRENT_MARK
1605                 if (block->cardtable_mod_union) {
1606                         sgen_free_internal_dynamic (block->cardtable_mod_union, CARDS_PER_BLOCK, INTERNAL_MEM_CARDTABLE_MOD_UNION);
1607                         block->cardtable_mod_union = NULL;
1608                 }
1609 #endif
1610
1611                 /* Count marked objects in the block */
1612                 for (i = 0; i < MS_NUM_MARK_WORDS; ++i) {
1613                         nused += bitcount (block->mark_words [i]);
1614                 }
1615                 if (nused) {
1616                         have_live = TRUE;
1617                 }
1618                 if (nused < count)
1619                         have_free = TRUE;
1620
1621                 if (!lazy_sweep)
1622                         sweep_block (block, TRUE);
1623
1624                 if (have_live) {
1625                         if (!has_pinned) {
1626                                 ++num_blocks [obj_size_index];
1627                                 slots_used [obj_size_index] += nused;
1628                                 slots_available [obj_size_index] += count;
1629                         }
1630
1631                         /*
1632                          * If there are free slots in the block, add
1633                          * the block to the corresponding free list.
1634                          */
1635                         if (have_free) {
1636                                 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1637                                 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1638                                 block->next_free = free_blocks [index];
1639                                 free_blocks [index] = block;
1640                         }
1641
1642                         update_heap_boundaries_for_block (block);
1643                 } else {
1644                         /*
1645                          * Blocks without live objects are removed from the
1646                          * block list and freed.
1647                          */
1648                         DELETE_BLOCK_IN_FOREACH ();
1649
1650                         binary_protocol_empty (MS_BLOCK_OBJ (block, 0), (char*)MS_BLOCK_OBJ (block, count) - (char*)MS_BLOCK_OBJ (block, 0));
1651 #if defined (FIXED_HEAP) || defined (BLOCK_INFO_IN_HEADER)
1652                         ms_free_block (block);
1653 #else
1654                         ms_free_block (block->block);
1655                         sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
1656 #endif
1657
1658                         --num_major_sections;
1659                 }
1660         } END_FOREACH_BLOCK;
1661         sgen_pointer_queue_remove_nulls (&allocated_blocks);
1662
1663         for (i = 0; i < num_block_obj_sizes; ++i) {
1664                 float usage = (float)slots_used [i] / (float)slots_available [i];
1665                 if (num_blocks [i] > 5 && usage < evacuation_threshold) {
1666                         g_assert_not_reached ();
1667                         evacuate_block_obj_sizes [i] = TRUE;
1668                         /*
1669                         g_print ("slot size %d - %d of %d used\n",
1670                                         block_obj_sizes [i], slots_used [i], slots_available [i]);
1671                         */
1672                 } else {
1673                         evacuate_block_obj_sizes [i] = FALSE;
1674                 }
1675 #ifdef SGEN_HAVE_CONCURRENT_MARK
1676                 {
1677                         mword total_bytes = block_obj_sizes [i] * slots_available [i];
1678                         total_evacuate_heap += total_bytes;
1679                         if (evacuate_block_obj_sizes [i])
1680                                 total_evacuate_saved += total_bytes - block_obj_sizes [i] * slots_used [i];
1681                 }
1682 #endif
1683         }
1684
1685 #ifdef SGEN_HAVE_CONCURRENT_MARK
1686         want_evacuation = (float)total_evacuate_saved / (float)total_evacuate_heap > (1 - concurrent_evacuation_threshold);
1687 #endif
1688
1689         have_swept = TRUE;
1690 }
1691
1692 static void
1693 major_sweep (void)
1694 {
1695         ms_sweep ();
1696 }
1697
1698 static int count_pinned_ref;
1699 static int count_pinned_nonref;
1700 static int count_nonpinned_ref;
1701 static int count_nonpinned_nonref;
1702
1703 static void
1704 count_nonpinned_callback (char *obj, size_t size, void *data)
1705 {
1706         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1707
1708         if (vtable->klass->has_references)
1709                 ++count_nonpinned_ref;
1710         else
1711                 ++count_nonpinned_nonref;
1712 }
1713
1714 static void
1715 count_pinned_callback (char *obj, size_t size, void *data)
1716 {
1717         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1718
1719         if (vtable->klass->has_references)
1720                 ++count_pinned_ref;
1721         else
1722                 ++count_pinned_nonref;
1723 }
1724
1725 static G_GNUC_UNUSED void
1726 count_ref_nonref_objs (void)
1727 {
1728         int total;
1729
1730         count_pinned_ref = 0;
1731         count_pinned_nonref = 0;
1732         count_nonpinned_ref = 0;
1733         count_nonpinned_nonref = 0;
1734
1735         major_iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, count_nonpinned_callback, NULL);
1736         major_iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, count_pinned_callback, NULL);
1737
1738         total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1739
1740         g_print ("ref: %d pinned %d non-pinned   non-ref: %d pinned %d non-pinned  --  %.1f\n",
1741                         count_pinned_ref, count_nonpinned_ref,
1742                         count_pinned_nonref, count_nonpinned_nonref,
1743                         (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1744 }
1745
1746 static int
1747 ms_calculate_block_obj_sizes (double factor, int *arr)
1748 {
1749         double target_size = sizeof (MonoObject);
1750         int num_sizes = 0;
1751         int last_size = 0;
1752
1753         do {
1754                 int target_count = (int)ceil (MS_BLOCK_FREE / target_size);
1755                 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1756
1757                 if (size != last_size) {
1758                         if (arr)
1759                                 arr [num_sizes] = size;
1760                         ++num_sizes;
1761                         last_size = size;
1762                 }
1763
1764                 target_size *= factor;
1765         } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1766
1767         return num_sizes;
1768 }
1769
1770 /* only valid during minor collections */
1771 static mword old_num_major_sections;
1772
1773 static void
1774 major_start_nursery_collection (void)
1775 {
1776 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1777         consistency_check ();
1778 #endif
1779
1780         old_num_major_sections = num_major_sections;
1781 }
1782
1783 static void
1784 major_finish_nursery_collection (void)
1785 {
1786 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1787         consistency_check ();
1788 #endif
1789         sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1790 }
1791
1792 static void
1793 major_start_major_collection (void)
1794 {
1795         int i;
1796
1797         /* clear the free lists */
1798         for (i = 0; i < num_block_obj_sizes; ++i) {
1799                 if (!evacuate_block_obj_sizes [i])
1800                         continue;
1801
1802                 free_block_lists [0][i] = NULL;
1803                 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1804         }
1805
1806         // Sweep all unswept blocks
1807         if (lazy_sweep) {
1808                 MSBlockInfo *block;
1809
1810                 MONO_GC_SWEEP_BEGIN (GENERATION_OLD, TRUE);
1811
1812                 FOREACH_BLOCK (block) {
1813                         sweep_block (block, TRUE);
1814                 } END_FOREACH_BLOCK;
1815
1816                 MONO_GC_SWEEP_END (GENERATION_OLD, TRUE);
1817         }
1818 }
1819
1820 static void
1821 major_finish_major_collection (ScannedObjectCounts *counts)
1822 {
1823 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
1824         if (binary_protocol_is_enabled ()) {
1825                 counts->num_scanned_objects = scanned_objects_list.next_slot;
1826
1827                 sgen_pointer_queue_sort_uniq (&scanned_objects_list);
1828                 counts->num_unique_scanned_objects = scanned_objects_list.next_slot;
1829
1830                 sgen_pointer_queue_clear (&scanned_objects_list);
1831         }
1832 #endif
1833 }
1834
1835 #if SIZEOF_VOID_P != 8
1836 static int
1837 compare_pointers (const void *va, const void *vb) {
1838         char *a = *(char**)va, *b = *(char**)vb;
1839         if (a < b)
1840                 return -1;
1841         if (a > b)
1842                 return 1;
1843         return 0;
1844 }
1845 #endif
1846
1847 static void
1848 major_have_computer_minor_collection_allowance (void)
1849 {
1850         size_t section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1851
1852         g_assert (have_swept);
1853
1854 #if SIZEOF_VOID_P != 8
1855         {
1856                 int i, num_empty_blocks_orig, num_blocks, arr_length;
1857                 void *block;
1858                 void **empty_block_arr;
1859                 void **rebuild_next;
1860
1861 #ifdef TARGET_WIN32
1862                 /*
1863                  * sgen_free_os_memory () asserts in mono_vfree () because windows doesn't like freeing the middle of
1864                  * a VirtualAlloc ()-ed block.
1865                  */
1866                 return;
1867 #endif
1868
1869                 if (num_empty_blocks <= section_reserve)
1870                         return;
1871                 SGEN_ASSERT (0, num_empty_blocks > 0, "section reserve can't be negative");
1872
1873                 num_empty_blocks_orig = num_empty_blocks;
1874                 empty_block_arr = (void**)sgen_alloc_internal_dynamic (sizeof (void*) * num_empty_blocks_orig,
1875                                 INTERNAL_MEM_MS_BLOCK_INFO_SORT, FALSE);
1876                 if (!empty_block_arr)
1877                         goto fallback;
1878
1879                 i = 0;
1880                 for (block = empty_blocks; block; block = *(void**)block)
1881                         empty_block_arr [i++] = block;
1882                 SGEN_ASSERT (0, i == num_empty_blocks, "empty block count wrong");
1883
1884                 sgen_qsort (empty_block_arr, num_empty_blocks, sizeof (void*), compare_pointers);
1885
1886                 /*
1887                  * We iterate over the free blocks, trying to find MS_BLOCK_ALLOC_NUM
1888                  * contiguous ones.  If we do, we free them.  If that's not enough to get to
1889                  * section_reserve, we halve the number of contiguous blocks we're looking
1890                  * for and have another go, until we're done with looking for pairs of
1891                  * blocks, at which point we give up and go to the fallback.
1892                  */
1893                 arr_length = num_empty_blocks_orig;
1894                 num_blocks = MS_BLOCK_ALLOC_NUM;
1895                 while (num_empty_blocks > section_reserve && num_blocks > 1) {
1896                         int first = -1;
1897                         int dest = 0;
1898
1899                         dest = 0;
1900                         for (i = 0; i < arr_length; ++i) {
1901                                 int d = dest;
1902                                 void *block = empty_block_arr [i];
1903                                 SGEN_ASSERT (0, block, "we're not shifting correctly");
1904                                 if (i != dest) {
1905                                         empty_block_arr [dest] = block;
1906                                         /*
1907                                          * This is not strictly necessary, but we're
1908                                          * cautious.
1909                                          */
1910                                         empty_block_arr [i] = NULL;
1911                                 }
1912                                 ++dest;
1913
1914                                 if (first < 0) {
1915                                         first = d;
1916                                         continue;
1917                                 }
1918
1919                                 SGEN_ASSERT (0, first >= 0 && d > first, "algorithm is wrong");
1920
1921                                 if ((char*)block != ((char*)empty_block_arr [d-1]) + MS_BLOCK_SIZE) {
1922                                         first = d;
1923                                         continue;
1924                                 }
1925
1926                                 if (d + 1 - first == num_blocks) {
1927                                         /*
1928                                          * We found num_blocks contiguous blocks.  Free them
1929                                          * and null their array entries.  As an optimization
1930                                          * we could, instead of nulling the entries, shift
1931                                          * the following entries over to the left, while
1932                                          * we're iterating.
1933                                          */
1934                                         int j;
1935                                         sgen_free_os_memory (empty_block_arr [first], MS_BLOCK_SIZE * num_blocks, SGEN_ALLOC_HEAP);
1936                                         for (j = first; j <= d; ++j)
1937                                                 empty_block_arr [j] = NULL;
1938                                         dest = first;
1939                                         first = -1;
1940
1941                                         num_empty_blocks -= num_blocks;
1942
1943                                         stat_major_blocks_freed += num_blocks;
1944                                         if (num_blocks == MS_BLOCK_ALLOC_NUM)
1945                                                 stat_major_blocks_freed_ideal += num_blocks;
1946                                         else
1947                                                 stat_major_blocks_freed_less_ideal += num_blocks;
1948
1949                                 }
1950                         }
1951
1952                         SGEN_ASSERT (0, dest <= i && dest <= arr_length, "array length is off");
1953                         arr_length = dest;
1954                         SGEN_ASSERT (0, arr_length == num_empty_blocks, "array length is off");
1955
1956                         num_blocks >>= 1;
1957                 }
1958
1959                 /* rebuild empty_blocks free list */
1960                 rebuild_next = (void**)&empty_blocks;
1961                 for (i = 0; i < arr_length; ++i) {
1962                         void *block = empty_block_arr [i];
1963                         SGEN_ASSERT (0, block, "we're missing blocks");
1964                         *rebuild_next = block;
1965                         rebuild_next = (void**)block;
1966                 }
1967                 *rebuild_next = NULL;
1968
1969                 /* free array */
1970                 sgen_free_internal_dynamic (empty_block_arr, sizeof (void*) * num_empty_blocks_orig, INTERNAL_MEM_MS_BLOCK_INFO_SORT);
1971         }
1972
1973         SGEN_ASSERT (0, num_empty_blocks >= 0, "we freed more blocks than we had in the first place?");
1974
1975  fallback:
1976         /*
1977          * This is our threshold.  If there's not more empty than used blocks, we won't
1978          * release uncontiguous blocks, in fear of fragmenting the address space.
1979          */
1980         if (num_empty_blocks <= num_major_sections)
1981                 return;
1982 #endif
1983
1984         while (num_empty_blocks > section_reserve) {
1985                 void *next = *(void**)empty_blocks;
1986                 sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP);
1987                 empty_blocks = next;
1988                 /*
1989                  * Needs not be atomic because this is running
1990                  * single-threaded.
1991                  */
1992                 --num_empty_blocks;
1993
1994                 ++stat_major_blocks_freed;
1995 #if SIZEOF_VOID_P != 8
1996                 ++stat_major_blocks_freed_individual;
1997 #endif
1998         }
1999 }
2000
2001 static void
2002 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
2003 {
2004         MSBlockInfo *block;
2005
2006         FOREACH_BLOCK (block) {
2007                 sgen_find_optimized_pin_queue_area (MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SKIP, MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE,
2008                                 &block->pin_queue_first_entry, &block->pin_queue_last_entry);
2009         } END_FOREACH_BLOCK;
2010 }
2011
2012 static void
2013 major_pin_objects (SgenGrayQueue *queue)
2014 {
2015         MSBlockInfo *block;
2016
2017         FOREACH_BLOCK (block) {
2018                 mark_pinned_objects_in_block (block, queue);
2019         } END_FOREACH_BLOCK;
2020 }
2021
2022 static void
2023 major_init_to_space (void)
2024 {
2025 }
2026
2027 static void
2028 major_report_pinned_memory_usage (void)
2029 {
2030         g_assert_not_reached ();
2031 }
2032
2033 static gint64
2034 major_get_used_size (void)
2035 {
2036         gint64 size = 0;
2037         MSBlockInfo *block;
2038
2039         FOREACH_BLOCK (block) {
2040                 int count = MS_BLOCK_FREE / block->obj_size;
2041                 void **iter;
2042                 size += count * block->obj_size;
2043                 for (iter = block->free_list; iter; iter = (void**)*iter)
2044                         size -= block->obj_size;
2045         } END_FOREACH_BLOCK;
2046
2047         return size;
2048 }
2049
2050 static size_t
2051 get_num_major_sections (void)
2052 {
2053         return num_major_sections;
2054 }
2055
2056 static gboolean
2057 major_handle_gc_param (const char *opt)
2058 {
2059         /*
2060         if (g_str_has_prefix (opt, "evacuation-threshold=")) {
2061                 const char *arg = strchr (opt, '=') + 1;
2062                 int percentage = atoi (arg);
2063                 if (percentage < 0 || percentage > 100) {
2064                         fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
2065                         exit (1);
2066                 }
2067                 evacuation_threshold = (float)percentage / 100.0f;
2068                 return TRUE;
2069                 } else */
2070         if (!strcmp (opt, "lazy-sweep")) {
2071                 lazy_sweep = TRUE;
2072                 return TRUE;
2073         } else if (!strcmp (opt, "no-lazy-sweep")) {
2074                 lazy_sweep = FALSE;
2075                 return TRUE;
2076         }
2077
2078         return FALSE;
2079 }
2080
2081 static void
2082 major_print_gc_param_usage (void)
2083 {
2084         fprintf (stderr,
2085                         ""
2086                         "  evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
2087                         "  (no-)lazy-sweep\n"
2088                         );
2089 }
2090
2091 static void
2092 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
2093 {
2094         MSBlockInfo *block;
2095         gboolean has_references;
2096
2097         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
2098                 if (has_references)
2099                         callback ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE);
2100         } END_FOREACH_BLOCK;
2101 }
2102
2103 #ifdef HEAVY_STATISTICS
2104 extern long long marked_cards;
2105 extern long long scanned_cards;
2106 extern long long scanned_objects;
2107 extern long long remarked_cards;
2108 #endif
2109
2110 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
2111 /*
2112  * MS blocks are 16K aligned.
2113  * Cardtables are 4K aligned, at least.
2114  * This means that the cardtable of a given block is 32 bytes aligned.
2115  */
2116 static guint8*
2117 initial_skip_card (guint8 *card_data)
2118 {
2119         mword *cards = (mword*)card_data;
2120         mword card;
2121         int i;
2122         for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
2123                 card = cards [i];
2124                 if (card)
2125                         break;
2126         }
2127
2128         if (i == CARD_WORDS_PER_BLOCK)
2129                 return card_data + CARDS_PER_BLOCK;
2130
2131 #if defined(__i386__) && defined(__GNUC__)
2132         return card_data + i * 4 +  (__builtin_ffs (card) - 1) / 8;
2133 #elif defined(__x86_64__) && defined(__GNUC__)
2134         return card_data + i * 8 +  (__builtin_ffsll (card) - 1) / 8;
2135 #elif defined(__s390x__) && defined(__GNUC__)
2136         return card_data + i * 8 +  (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
2137 #else
2138         for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
2139                 if (card_data [i])
2140                         return &card_data [i];
2141         }
2142         return card_data;
2143 #endif
2144 }
2145
2146
2147 static G_GNUC_UNUSED guint8*
2148 skip_card (guint8 *card_data, guint8 *card_data_end)
2149 {
2150         while (card_data < card_data_end && !*card_data)
2151                 ++card_data;
2152         return card_data;
2153 }
2154
2155 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
2156 #define MS_BLOCK_OBJ_FAST(b,os,i)                       ((b) + MS_BLOCK_SKIP + (os) * (i))
2157 #define MS_OBJ_ALLOCED_FAST(o,b)                (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
2158
2159 static void
2160 major_scan_card_table (gboolean mod_union, SgenGrayQueue *queue)
2161 {
2162         MSBlockInfo *block;
2163         gboolean has_references;
2164         ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
2165
2166 #ifdef SGEN_HAVE_CONCURRENT_MARK
2167         if (!concurrent_mark)
2168                 g_assert (!mod_union);
2169 #else
2170         g_assert (!mod_union);
2171 #endif
2172
2173         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
2174                 int block_obj_size;
2175                 char *block_start;
2176
2177                 if (!has_references)
2178                         continue;
2179
2180                 block_obj_size = block->obj_size;
2181                 block_start = MS_BLOCK_FOR_BLOCK_INFO (block);
2182
2183                 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
2184                         guint8 *cards;
2185 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
2186                         guint8 cards_data [CARDS_PER_BLOCK];
2187 #endif
2188                         char *obj, *end, *base;
2189
2190                         if (mod_union) {
2191 #ifdef SGEN_HAVE_CONCURRENT_MARK
2192                                 cards = block->cardtable_mod_union;
2193                                 /*
2194                                  * This happens when the nursery
2195                                  * collection that precedes finishing
2196                                  * the concurrent collection allocates
2197                                  * new major blocks.
2198                                  */
2199                                 if (!cards)
2200                                         continue;
2201 #endif
2202                         } else {
2203                         /*We can avoid the extra copy since the remark cardtable was cleaned before */
2204 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
2205                                 cards = sgen_card_table_get_card_scan_address ((mword)block_start);
2206 #else
2207                                 cards = cards_data;
2208                                 if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
2209                                         continue;
2210 #endif
2211                         }
2212
2213                         obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
2214                         end = block_start + MS_BLOCK_SIZE;
2215                         base = sgen_card_table_align_pointer (obj);
2216
2217                         while (obj < end) {
2218                                 size_t card_offset;
2219
2220                                 if (!block->swept)
2221                                         sweep_block (block, FALSE);
2222
2223                                 if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
2224                                         goto next_large;
2225
2226                                 if (mod_union) {
2227                                         /* FIXME: do this more efficiently */
2228                                         int w, b;
2229                                         MS_CALC_MARK_BIT (w, b, obj);
2230                                         if (!MS_MARK_BIT (block, w, b))
2231                                                 goto next_large;
2232                                 }
2233
2234                                 card_offset = (obj - base) >> CARD_BITS;
2235                                 sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, mod_union, queue);
2236
2237                         next_large:
2238                                 obj += block_obj_size;
2239                         }
2240                 } else {
2241                         guint8 *card_data, *card_base;
2242                         guint8 *card_data_end;
2243
2244                         /*
2245                          * This is safe in face of card aliasing for the following reason:
2246                          *
2247                          * Major blocks are 16k aligned, or 32 cards aligned.
2248                          * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
2249                          * sizes, they won't overflow the cardtable overlap modulus.
2250                          */
2251                         if (mod_union) {
2252 #ifdef SGEN_HAVE_CONCURRENT_MARK
2253                                 card_data = card_base = block->cardtable_mod_union;
2254                                 /*
2255                                  * This happens when the nursery
2256                                  * collection that precedes finishing
2257                                  * the concurrent collection allocates
2258                                  * new major blocks.
2259                                  */
2260                                 if (!card_data)
2261                                         continue;
2262 #else
2263                                 g_assert_not_reached ();
2264                                 card_data = NULL;
2265 #endif
2266                         } else {
2267                                 card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
2268                         }
2269                         card_data_end = card_data + CARDS_PER_BLOCK;
2270
2271                         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)) {
2272                                 size_t index;
2273                                 size_t idx = card_data - card_base;
2274                                 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
2275                                 char *end = start + CARD_SIZE_IN_BYTES;
2276                                 char *first_obj, *obj;
2277
2278                                 HEAVY_STAT (++scanned_cards);
2279
2280                                 if (!*card_data)
2281                                         continue;
2282
2283                                 if (!block->swept)
2284                                         sweep_block (block, FALSE);
2285
2286                                 HEAVY_STAT (++marked_cards);
2287
2288                                 sgen_card_table_prepare_card_for_scanning (card_data);
2289
2290                                 if (idx == 0)
2291                                         index = 0;
2292                                 else
2293                                         index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
2294
2295                                 obj = first_obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
2296                                 while (obj < end) {
2297                                         if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
2298                                                 goto next_small;
2299
2300                                         if (mod_union) {
2301                                                 /* FIXME: do this more efficiently */
2302                                                 int w, b;
2303                                                 MS_CALC_MARK_BIT (w, b, obj);
2304                                                 if (!MS_MARK_BIT (block, w, b))
2305                                                         goto next_small;
2306                                         }
2307
2308                                         HEAVY_STAT (++scanned_objects);
2309                                         scan_func (obj, sgen_obj_get_descriptor (obj), queue);
2310                                 next_small:
2311                                         obj += block_obj_size;
2312                                 }
2313                                 HEAVY_STAT (if (*card_data) ++remarked_cards);
2314                                 binary_protocol_card_scan (first_obj, obj - first_obj);
2315                         }
2316                 }
2317         } END_FOREACH_BLOCK;
2318 }
2319
2320 static void
2321 major_count_cards (long long *num_total_cards, long long *num_marked_cards)
2322 {
2323         MSBlockInfo *block;
2324         gboolean has_references;
2325         long long total_cards = 0;
2326         long long marked_cards = 0;
2327
2328         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
2329                 guint8 *cards = sgen_card_table_get_card_scan_address ((mword) MS_BLOCK_FOR_BLOCK_INFO (block));
2330                 int i;
2331
2332                 if (!has_references)
2333                         continue;
2334
2335                 total_cards += CARDS_PER_BLOCK;
2336                 for (i = 0; i < CARDS_PER_BLOCK; ++i) {
2337                         if (cards [i])
2338                                 ++marked_cards;
2339                 }
2340         } END_FOREACH_BLOCK;
2341
2342         *num_total_cards = total_cards;
2343         *num_marked_cards = marked_cards;
2344 }
2345
2346 #ifdef SGEN_HAVE_CONCURRENT_MARK
2347 static void
2348 update_cardtable_mod_union (void)
2349 {
2350         MSBlockInfo *block;
2351
2352         FOREACH_BLOCK (block) {
2353                 size_t num_cards;
2354
2355                 block->cardtable_mod_union = sgen_card_table_update_mod_union (block->cardtable_mod_union,
2356                                 MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE, &num_cards);
2357
2358                 SGEN_ASSERT (0, num_cards == CARDS_PER_BLOCK, "Number of cards calculation is wrong");
2359         } END_FOREACH_BLOCK;
2360 }
2361
2362 static guint8*
2363 major_get_cardtable_mod_union_for_object (char *obj)
2364 {
2365         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
2366         return &block->cardtable_mod_union [(obj - (char*)sgen_card_table_align_pointer (MS_BLOCK_FOR_BLOCK_INFO (block))) >> CARD_BITS];
2367 }
2368 #endif
2369
2370 static void
2371 alloc_free_block_lists (MSBlockInfo ***lists)
2372 {
2373         int i;
2374         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
2375                 lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2376 }
2377
2378 #undef pthread_create
2379
2380 static void
2381 post_param_init (SgenMajorCollector *collector)
2382 {
2383         collector->sweeps_lazily = lazy_sweep;
2384 }
2385
2386 #ifdef SGEN_HAVE_CONCURRENT_MARK
2387 static void
2388 sgen_marksweep_init_internal (SgenMajorCollector *collector, gboolean is_concurrent)
2389 #else // SGEN_HAVE_CONCURRENT_MARK
2390 #error unknown configuration
2391 #endif // SGEN_HAVE_CONCURRENT_MARK
2392 {
2393         int i;
2394
2395         sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
2396
2397         num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
2398         block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2399         ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
2400
2401         evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2402         for (i = 0; i < num_block_obj_sizes; ++i)
2403                 evacuate_block_obj_sizes [i] = FALSE;
2404
2405         /*
2406         {
2407                 int i;
2408                 g_print ("block object sizes:\n");
2409                 for (i = 0; i < num_block_obj_sizes; ++i)
2410                         g_print ("%d\n", block_obj_sizes [i]);
2411         }
2412         */
2413
2414         alloc_free_block_lists (free_block_lists);
2415
2416         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
2417                 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
2418         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
2419                 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
2420
2421         mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
2422         mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
2423         mono_counters_register ("# major blocks lazy swept", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_lazy_swept);
2424         mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
2425 #if SIZEOF_VOID_P != 8
2426         mono_counters_register ("# major blocks freed ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_ideal);
2427         mono_counters_register ("# major blocks freed less ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_less_ideal);
2428         mono_counters_register ("# major blocks freed individually", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_individual);
2429         mono_counters_register ("# major blocks allocated less ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced_less_ideal);
2430 #endif
2431
2432         collector->section_size = MAJOR_SECTION_SIZE;
2433
2434 #ifdef SGEN_HAVE_CONCURRENT_MARK
2435         concurrent_mark = is_concurrent;
2436         if (is_concurrent) {
2437                 collector->is_concurrent = TRUE;
2438                 collector->want_synchronous_collection = &want_evacuation;
2439         } else
2440 #endif
2441         {
2442                 collector->is_concurrent = FALSE;
2443                 collector->want_synchronous_collection = NULL;
2444         }
2445         collector->get_and_reset_num_major_objects_marked = major_get_and_reset_num_major_objects_marked;
2446         collector->supports_cardtable = TRUE;
2447
2448         collector->have_swept = &have_swept;
2449
2450         collector->alloc_heap = major_alloc_heap;
2451         collector->is_object_live = major_is_object_live;
2452         collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2453         collector->alloc_degraded = major_alloc_degraded;
2454
2455         collector->alloc_object = major_alloc_object;
2456         collector->free_pinned_object = free_pinned_object;
2457         collector->iterate_objects = major_iterate_objects;
2458         collector->free_non_pinned_object = major_free_non_pinned_object;
2459         collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2460         collector->pin_objects = major_pin_objects;
2461         collector->pin_major_object = pin_major_object;
2462         collector->scan_card_table = major_scan_card_table;
2463         collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2464 #ifdef SGEN_HAVE_CONCURRENT_MARK
2465         if (is_concurrent) {
2466                 collector->update_cardtable_mod_union = update_cardtable_mod_union;
2467                 collector->get_cardtable_mod_union_for_object = major_get_cardtable_mod_union_for_object;
2468         }
2469 #endif
2470         collector->init_to_space = major_init_to_space;
2471         collector->sweep = major_sweep;
2472         collector->check_scan_starts = major_check_scan_starts;
2473         collector->dump_heap = major_dump_heap;
2474         collector->get_used_size = major_get_used_size;
2475         collector->start_nursery_collection = major_start_nursery_collection;
2476         collector->finish_nursery_collection = major_finish_nursery_collection;
2477         collector->start_major_collection = major_start_major_collection;
2478         collector->finish_major_collection = major_finish_major_collection;
2479         collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2480         collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2481         collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2482         collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2483         collector->get_num_major_sections = get_num_major_sections;
2484         collector->handle_gc_param = major_handle_gc_param;
2485         collector->print_gc_param_usage = major_print_gc_param_usage;
2486         collector->post_param_init = post_param_init;
2487         collector->is_valid_object = major_is_valid_object;
2488         collector->describe_pointer = major_describe_pointer;
2489         collector->count_cards = major_count_cards;
2490
2491         collector->major_ops.copy_or_mark_object = major_copy_or_mark_object_canonical;
2492         collector->major_ops.scan_object = major_scan_object;
2493 #ifdef SGEN_HAVE_CONCURRENT_MARK
2494         if (is_concurrent) {
2495                 collector->major_concurrent_ops.copy_or_mark_object = major_copy_or_mark_object_concurrent_canonical;
2496                 collector->major_concurrent_ops.scan_object = major_scan_object_concurrent;
2497                 collector->major_concurrent_ops.scan_vtype = major_scan_vtype_concurrent;
2498         }
2499 #endif
2500
2501 #if !defined (FIXED_HEAP) && !defined (SGEN_PARALLEL_MARK)
2502         /* FIXME: this will not work with evacuation or the split nursery. */
2503         if (!is_concurrent)
2504                 collector->drain_gray_stack = drain_gray_stack;
2505
2506 #ifdef HEAVY_STATISTICS
2507         mono_counters_register ("Optimized copy", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy);
2508         mono_counters_register ("Optimized copy nursery", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_nursery);
2509         mono_counters_register ("Optimized copy nursery forwarded", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_nursery_forwarded);
2510         mono_counters_register ("Optimized copy nursery pinned", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_nursery_pinned);
2511 #ifdef SGEN_MARK_ON_ENQUEUE
2512         mono_counters_register ("Optimized copy major", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major);
2513         mono_counters_register ("Optimized copy major small fast", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major_small_fast);
2514         mono_counters_register ("Optimized copy major small slow", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major_small_slow);
2515         mono_counters_register ("Optimized copy major large", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_copy_major_large);
2516 #endif
2517         mono_counters_register ("Optimized major mark", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_mark);
2518         mono_counters_register ("Optimized major mark small", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_mark_small);
2519         mono_counters_register ("Optimized major mark large", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_mark_large);
2520         mono_counters_register ("Optimized major scan", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan);
2521         mono_counters_register ("Optimized major scan no refs", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan_no_refs);
2522 #ifdef DESCRIPTOR_FAST_PATH
2523         mono_counters_register ("Optimized major scan slow", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan_slow);
2524         mono_counters_register ("Optimized major scan fast", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_optimized_major_scan_fast);
2525 #endif
2526
2527         mono_counters_register ("Gray stack drain loops", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_drain_loops);
2528         mono_counters_register ("Gray stack prefetch fills", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_drain_prefetch_fills);
2529         mono_counters_register ("Gray stack prefetch failures", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_drain_prefetch_fill_failures);
2530 #endif
2531 #endif
2532
2533 #ifdef HEAVY_STATISTICS
2534         mono_mutex_init (&scanned_objects_list_lock);
2535 #endif
2536
2537         SGEN_ASSERT (0, SGEN_MAX_SMALL_OBJ_SIZE <= MS_BLOCK_FREE / 2, "MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2");
2538
2539         /*cardtable requires major pages to be 8 cards aligned*/
2540         g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);
2541 }
2542
2543 #ifdef SGEN_HAVE_CONCURRENT_MARK
2544 void
2545 sgen_marksweep_init (SgenMajorCollector *collector)
2546 {
2547         sgen_marksweep_init_internal (collector, FALSE);
2548 }
2549
2550 void
2551 sgen_marksweep_conc_init (SgenMajorCollector *collector)
2552 {
2553         sgen_marksweep_init_internal (collector, TRUE);
2554 }
2555 #endif
2556
2557 #endif