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
  46 #define SGEN_HAVE_CONCURRENT_MARK
  47
  48 #if defined(ARCH_MIN_MS_BLOCK_SIZE) && defined(ARCH_MIN_MS_BLOCK_SIZE_SHIFT)
  49 #define MS_BLOCK_SIZE   ARCH_MIN_MS_BLOCK_SIZE
  50 #define MS_BLOCK_SIZE_SHIFT     ARCH_MIN_MS_BLOCK_SIZE_SHIFT
  51 #else
  52 #define MS_BLOCK_SIZE   (16*1024)
  53 #define MS_BLOCK_SIZE_SHIFT     14
  54 #endif
  55 #define MAJOR_SECTION_SIZE      MS_BLOCK_SIZE
  56 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
  57
  58 /*
  59  * Don't allocate single blocks, but alloc a contingent of this many
  60  * blocks in one swoop.  This must be a power of two.
  61  */
  62 #define MS_BLOCK_ALLOC_NUM      32
  63
  64 /*
  65  * Number of bytes before the first object in a block.  At the start
  66  * of a block is the MSBlockHeader, then opional padding, then come
  67  * the objects, so this must be >= sizeof (MSBlockHeader).
  68  */
  69 #define MS_BLOCK_SKIP   16
  70
  71 #define MS_BLOCK_FREE   (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
  72
  73 #define MS_NUM_MARK_WORDS       ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
  74
  75 #if SGEN_MAX_SMALL_OBJ_SIZE > MS_BLOCK_FREE / 2
  76 #error MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2
  77 #endif
  78
  79 typedef struct _MSBlockInfo MSBlockInfo;
  80 struct _MSBlockInfo {
  81         int obj_size;
  82         int obj_size_index;
  83         unsigned int pinned : 1;
  84         unsigned int has_references : 1;
  85         unsigned int has_pinned : 1;    /* means cannot evacuate */
  86         unsigned int is_to_space : 1;
  87         unsigned int swept : 1;
  88         char *block;
  89         void **free_list;
  90         MSBlockInfo *next_free;
  91         size_t pin_queue_first_entry;
  92         size_t pin_queue_last_entry;
  93 #ifdef SGEN_HAVE_CONCURRENT_MARK
  94         guint8 *cardtable_mod_union;
  95 #endif
  96         mword mark_words [MS_NUM_MARK_WORDS];
  97 };
  98
  99 #define MS_BLOCK_FOR_BLOCK_INFO(b)      ((b)->block)
 100
 101 #define MS_BLOCK_OBJ(b,i)               (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (b)->obj_size * (i))
 102 #define MS_BLOCK_OBJ_FOR_SIZE(b,i,obj_size)             (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (obj_size) * (i))
 103 #define MS_BLOCK_DATA_FOR_OBJ(o)        ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
 104
 105 typedef struct {
 106         MSBlockInfo *info;
 107 } MSBlockHeader;
 108
 109 #define MS_BLOCK_FOR_OBJ(o)             (((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
 110
 111 /* object index will always be small */
 112 #define MS_BLOCK_OBJ_INDEX(o,b) ((int)(((char*)(o) - (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP)) / (b)->obj_size))
 113
 114 //casting to int is fine since blocks are 32k
 115 #define MS_CALC_MARK_BIT(w,b,o)         do {                            \
 116                 int i = ((int)((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o)))) >> SGEN_ALLOC_ALIGN_BITS; \
 117                 if (sizeof (mword) == 4) {                              \
 118                         (w) = i >> 5;                                   \
 119                         (b) = i & 31;                                   \
 120                 } else {                                                \
 121                         (w) = i >> 6;                                   \
 122                         (b) = i & 63;                                   \
 123                 }                                                       \
 124         } while (0)
 125
 126 #define MS_MARK_BIT(bl,w,b)     ((bl)->mark_words [(w)] & (ONE_P << (b)))
 127 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (ONE_P << (b)))
 128 #define MS_PAR_SET_MARK_BIT(was_marked,bl,w,b)  do {                    \
 129                 mword __old = (bl)->mark_words [(w)];                   \
 130                 mword __bitmask = ONE_P << (b);                         \
 131                 if (__old & __bitmask) {                                \
 132                         was_marked = TRUE;                              \
 133                         break;                                          \
 134                 }                                                       \
 135                 if (SGEN_CAS_PTR ((gpointer*)&(bl)->mark_words [(w)],   \
 136                                                 (gpointer)(__old | __bitmask), \
 137                                                 (gpointer)__old) ==     \
 138                                 (gpointer)__old) {                      \
 139                         was_marked = FALSE;                             \
 140                         break;                                          \
 141                 }                                                       \
 142         } while (1)
 143
 144 #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))
 145
 146 #define MS_BLOCK_OBJ_SIZE_FACTOR        (sqrt (2.0))
 147
 148 /*
 149  * This way we can lookup block object size indexes for sizes up to
 150  * 256 bytes with a single load.
 151  */
 152 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES      32
 153
 154 static int *block_obj_sizes;
 155 static int num_block_obj_sizes;
 156 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
 157
 158 #define MS_BLOCK_FLAG_PINNED    1
 159 #define MS_BLOCK_FLAG_REFS      2
 160
 161 #define MS_BLOCK_TYPE_MAX       4
 162
 163 static gboolean *evacuate_block_obj_sizes;
 164 static float evacuation_threshold = 0.666f;
 165 #ifdef SGEN_HAVE_CONCURRENT_MARK
 166 static float concurrent_evacuation_threshold = 0.666f;
 167 static gboolean want_evacuation = FALSE;
 168 #endif
 169
 170 static gboolean lazy_sweep = TRUE;
 171 static gboolean have_swept;
 172
 173 #ifdef SGEN_HAVE_CONCURRENT_MARK
 174 static gboolean concurrent_mark;
 175 #endif
 176
 177 #define BLOCK_IS_TAGGED_HAS_REFERENCES(bl)      SGEN_POINTER_IS_TAGGED_1 ((bl))
 178 #define BLOCK_TAG_HAS_REFERENCES(bl)            SGEN_POINTER_TAG_1 ((bl))
 179 #define BLOCK_UNTAG_HAS_REFERENCES(bl)          SGEN_POINTER_UNTAG_1 ((bl))
 180
 181 #define BLOCK_TAG(bl)   ((bl)->has_references ? BLOCK_TAG_HAS_REFERENCES ((bl)) : (bl))
 182
 183 /* all allocated blocks in the system */
 184 static SgenPointerQueue allocated_blocks;
 185
 186 /* non-allocated block free-list */
 187 static void *empty_blocks = NULL;
 188 static size_t num_empty_blocks = 0;
 189
 190 #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]);
 191 #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));
 192 #define END_FOREACH_BLOCK       } }
 193 #define DELETE_BLOCK_IN_FOREACH()       (allocated_blocks.data [__index] = NULL)
 194
 195 static size_t num_major_sections = 0;
 196 /* one free block list for each block object size */
 197 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
 198
 199 static long long stat_major_blocks_alloced = 0;
 200 static long long stat_major_blocks_freed = 0;
 201 static long long stat_major_blocks_lazy_swept = 0;
 202 static long long stat_major_objects_evacuated = 0;
 203
 204 #if SIZEOF_VOID_P != 8
 205 static long long stat_major_blocks_freed_ideal = 0;
 206 static long long stat_major_blocks_freed_less_ideal = 0;
 207 static long long stat_major_blocks_freed_individual = 0;
 208 static long long stat_major_blocks_alloced_less_ideal = 0;
 209 #endif
 210
 211 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
 212 static long long num_major_objects_marked = 0;
 213 #define INC_NUM_MAJOR_OBJECTS_MARKED()  (++num_major_objects_marked)
 214 #else
 215 #define INC_NUM_MAJOR_OBJECTS_MARKED()
 216 #endif
 217
 218 static void
 219 sweep_block (MSBlockInfo *block, gboolean during_major_collection);
 220
 221 static int
 222 ms_find_block_obj_size_index (size_t size)
 223 {
 224         int i;
 225         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);
 226         for (i = 0; i < num_block_obj_sizes; ++i)
 227                 if (block_obj_sizes [i] >= size)
 228                         return i;
 229         g_error ("no object of size %d\n", size);
 230 }
 231
 232 #define FREE_BLOCKS_FROM(lists,p,r)     (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
 233 #define FREE_BLOCKS(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 234
 235 #define MS_BLOCK_OBJ_SIZE_INDEX(s)                              \
 236         (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ?      \
 237          fast_block_obj_size_indexes [((s)+7)>>3] :             \
 238          ms_find_block_obj_size_index ((s)))
 239
 240 static void*
 241 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 242 {
 243         char *start;
 244         if (nursery_align)
 245                 start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 246         else
 247                 start = sgen_alloc_os_memory (nursery_size, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 248
 249         return start;
 250 }
 251
 252 static void
 253 update_heap_boundaries_for_block (MSBlockInfo *block)
 254 {
 255         sgen_update_heap_boundaries ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), (mword)MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE);
 256 }
 257
 258 static void*
 259 ms_get_empty_block (void)
 260 {
 261         char *p;
 262         int i;
 263         void *block, *empty, *next;
 264
 265  retry:
 266         if (!empty_blocks) {
 267                 /*
 268                  * We try allocating MS_BLOCK_ALLOC_NUM blocks first.  If that's
 269                  * unsuccessful, we halve the number of blocks and try again, until we're at
 270                  * 1.  If that doesn't work, either, we assert.
 271                  */
 272                 int alloc_num = MS_BLOCK_ALLOC_NUM;
 273                 for (;;) {
 274                         p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * alloc_num, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE,
 275                                         alloc_num == 1 ? "major heap section" : NULL);
 276                         if (p)
 277                                 break;
 278                         alloc_num >>= 1;
 279                 }
 280
 281                 for (i = 0; i < alloc_num; ++i) {
 282                         block = p;
 283                         /*
 284                          * We do the free list update one after the
 285                          * other so that other threads can use the new
 286                          * blocks as quickly as possible.
 287                          */
 288                         do {
 289                                 empty = empty_blocks;
 290                                 *(void**)block = empty;
 291                         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
 292                         p += MS_BLOCK_SIZE;
 293                 }
 294
 295                 SGEN_ATOMIC_ADD_P (num_empty_blocks, alloc_num);
 296
 297                 stat_major_blocks_alloced += alloc_num;
 298 #if SIZEOF_VOID_P != 8
 299                 if (alloc_num != MS_BLOCK_ALLOC_NUM)
 300                         stat_major_blocks_alloced_less_ideal += alloc_num;
 301 #endif
 302         }
 303
 304         do {
 305                 empty = empty_blocks;
 306                 if (!empty)
 307                         goto retry;
 308                 block = empty;
 309                 next = *(void**)block;
 310         } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
 311
 312         SGEN_ATOMIC_ADD_P (num_empty_blocks, -1);
 313
 314         *(void**)block = NULL;
 315
 316         g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
 317
 318         return block;
 319 }
 320
 321 static void
 322 ms_free_block (void *block)
 323 {
 324         void *empty;
 325
 326         sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 327         memset (block, 0, MS_BLOCK_SIZE);
 328
 329         do {
 330                 empty = empty_blocks;
 331                 *(void**)block = empty;
 332         } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
 333
 334         SGEN_ATOMIC_ADD_P (num_empty_blocks, 1);
 335 }
 336
 337 //#define MARKSWEEP_CONSISTENCY_CHECK
 338
 339 #ifdef MARKSWEEP_CONSISTENCY_CHECK
 340 static void
 341 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
 342 {
 343         MSBlockInfo *b;
 344
 345         for (; block; block = block->next_free) {
 346                 g_assert (block->obj_size == size);
 347                 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
 348
 349                 /* blocks in the free lists must have at least
 350                    one free slot */
 351                 if (block->swept)
 352                         g_assert (block->free_list);
 353
 354                 /* the block must be in the allocated_blocks array */
 355                 g_assert (sgen_pointer_queue_find (&allocated_blocks, BLOCK_TAG (block)) != (size_t)-1);
 356         }
 357 }
 358
 359 static void
 360 check_empty_blocks (void)
 361 {
 362         void *p;
 363         size_t i = 0;
 364         for (p = empty_blocks; p; p = *(void**)p)
 365                 ++i;
 366         g_assert (i == num_empty_blocks);
 367 }
 368
 369 static void
 370 consistency_check (void)
 371 {
 372         MSBlockInfo *block;
 373         int i;
 374
 375         /* check all blocks */
 376         FOREACH_BLOCK (block) {
 377                 int count = MS_BLOCK_FREE / block->obj_size;
 378                 int num_free = 0;
 379                 void **free;
 380
 381                 /* check block header */
 382                 g_assert (((MSBlockHeader*)block->block)->info == block);
 383
 384                 /* count number of free slots */
 385                 for (i = 0; i < count; ++i) {
 386                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 387                         if (!MS_OBJ_ALLOCED (obj, block))
 388                                 ++num_free;
 389                 }
 390
 391                 /* check free list */
 392                 for (free = block->free_list; free; free = (void**)*free) {
 393                         g_assert (MS_BLOCK_FOR_OBJ (free) == block);
 394                         --num_free;
 395                 }
 396                 g_assert (num_free == 0);
 397
 398                 /* check all mark words are zero */
 399                 if (block->swept) {
 400                         for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
 401                                 g_assert (block->mark_words [i] == 0);
 402                 }
 403         } END_FOREACH_BLOCK;
 404
 405         /* check free blocks */
 406         for (i = 0; i < num_block_obj_sizes; ++i) {
 407                 int j;
 408                 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
 409                         check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
 410         }
 411
 412         check_empty_blocks ();
 413 }
 414 #endif
 415
 416 static gboolean
 417 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
 418 {
 419         int size = block_obj_sizes [size_index];
 420         int count = MS_BLOCK_FREE / size;
 421         MSBlockInfo *info;
 422         MSBlockHeader *header;
 423         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 424         char *obj_start;
 425         int i;
 426
 427         if (!sgen_memgov_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
 428                 return FALSE;
 429
 430         info = sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
 431
 432         SGEN_ASSERT (9, count >= 2, "block with %d objects, it must hold at least 2", count);
 433
 434         info->obj_size = size;
 435         info->obj_size_index = size_index;
 436         info->pinned = pinned;
 437         info->has_references = has_references;
 438         info->has_pinned = pinned;
 439         /*
 440          * Blocks that are to-space are not evacuated from.  During an major collection
 441          * blocks are allocated for two reasons: evacuating objects from the nursery and
 442          * evacuating them from major blocks marked for evacuation.  In both cases we don't
 443          * want further evacuation.
 444          */
 445         info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD);
 446         info->swept = 1;
 447         info->block = ms_get_empty_block ();
 448
 449         header = (MSBlockHeader*) info->block;
 450         header->info = info;
 451 #ifdef SGEN_HAVE_CONCURRENT_MARK
 452         info->cardtable_mod_union = NULL;
 453 #endif
 454
 455         update_heap_boundaries_for_block (info);
 456
 457         /* build free list */
 458         obj_start = MS_BLOCK_FOR_BLOCK_INFO (info) + MS_BLOCK_SKIP;
 459         info->free_list = (void**)obj_start;
 460         /* we're skipping the last one - it must be nulled */
 461         for (i = 0; i < count - 1; ++i) {
 462                 char *next_obj_start = obj_start + size;
 463                 *(void**)obj_start = next_obj_start;
 464                 obj_start = next_obj_start;
 465         }
 466         /* the last one */
 467         *(void**)obj_start = NULL;
 468
 469         info->next_free = free_blocks [size_index];
 470         free_blocks [size_index] = info;
 471
 472         sgen_pointer_queue_add (&allocated_blocks, BLOCK_TAG (info));
 473
 474         ++num_major_sections;
 475         return TRUE;
 476 }
 477
 478 static gboolean
 479 obj_is_from_pinned_alloc (char *ptr)
 480 {
 481         MSBlockInfo *block;
 482
 483         FOREACH_BLOCK (block) {
 484                 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE)
 485                         return block->pinned;
 486         } END_FOREACH_BLOCK;
 487         return FALSE;
 488 }
 489
 490 static void*
 491 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
 492 {
 493         MSBlockInfo *block;
 494         void *obj;
 495
 496         block = free_blocks [size_index];
 497         SGEN_ASSERT (9, block, "no free block to unlink from free_blocks %p size_index %d", free_blocks, size_index);
 498
 499         if (G_UNLIKELY (!block->swept)) {
 500                 stat_major_blocks_lazy_swept ++;
 501                 sweep_block (block, FALSE);
 502         }
 503
 504         obj = block->free_list;
 505         SGEN_ASSERT (9, obj, "block %p in free list had no available object to alloc from", block);
 506
 507         block->free_list = *(void**)obj;
 508         if (!block->free_list) {
 509                 free_blocks [size_index] = block->next_free;
 510                 block->next_free = NULL;
 511         }
 512
 513         return obj;
 514 }
 515
 516 static void*
 517 alloc_obj (MonoVTable *vtable, size_t size, gboolean pinned, gboolean has_references)
 518 {
 519         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 520         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 521         void *obj;
 522
 523         if (!free_blocks [size_index]) {
 524                 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
 525                         return NULL;
 526         }
 527
 528         obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
 529
 530         *(MonoVTable**)obj = vtable;
 531
 532         return obj;
 533 }
 534
 535 static void*
 536 major_alloc_object (MonoVTable *vtable, size_t size, gboolean has_references)
 537 {
 538         return alloc_obj (vtable, size, FALSE, has_references);
 539 }
 540
 541 /*
 542  * We're not freeing the block if it's empty.  We leave that work for
 543  * the next major collection.
 544  *
 545  * This is just called from the domain clearing code, which runs in a
 546  * single thread and has the GC lock, so we don't need an extra lock.
 547  */
 548 static void
 549 free_object (char *obj, size_t size, gboolean pinned)
 550 {
 551         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 552         int word, bit;
 553
 554         if (!block->swept)
 555                 sweep_block (block, FALSE);
 556         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);
 557         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p is already free", obj);
 558         MS_CALC_MARK_BIT (word, bit, obj);
 559         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p has mark bit set");
 560         if (!block->free_list) {
 561                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
 562                 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 563                 SGEN_ASSERT (9, !block->next_free, "block %p doesn't have a free-list of object but belongs to a free-list of blocks");
 564                 block->next_free = free_blocks [size_index];
 565                 free_blocks [size_index] = block;
 566         }
 567         memset (obj, 0, size);
 568         *(void**)obj = block->free_list;
 569         block->free_list = (void**)obj;
 570 }
 571
 572 static void
 573 major_free_non_pinned_object (char *obj, size_t size)
 574 {
 575         free_object (obj, size, FALSE);
 576 }
 577
 578 /* size is a multiple of SGEN_ALLOC_ALIGN */
 579 static void*
 580 major_alloc_small_pinned_obj (MonoVTable *vtable, size_t size, gboolean has_references)
 581 {
 582         void *res;
 583
 584         res = alloc_obj (vtable, size, TRUE, has_references);
 585          /*If we failed to alloc memory, we better try releasing memory
 586           *as pinned alloc is requested by the runtime.
 587           */
 588          if (!res) {
 589                 sgen_perform_collection (0, GENERATION_OLD, "pinned alloc failure", TRUE);
 590                 res = alloc_obj (vtable, size, TRUE, has_references);
 591          }
 592          return res;
 593 }
 594
 595 static void
 596 free_pinned_object (char *obj, size_t size)
 597 {
 598         free_object (obj, size, TRUE);
 599 }
 600
 601 /*
 602  * size is already rounded up and we hold the GC lock.
 603  */
 604 static void*
 605 major_alloc_degraded (MonoVTable *vtable, size_t size)
 606 {
 607         void *obj;
 608         size_t old_num_sections;
 609
 610         old_num_sections = num_major_sections;
 611
 612         obj = alloc_obj (vtable, size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
 613         if (G_LIKELY (obj)) {
 614                 HEAVY_STAT (++stat_objects_alloced_degraded);
 615                 HEAVY_STAT (stat_bytes_alloced_degraded += size);
 616                 g_assert (num_major_sections >= old_num_sections);
 617                 sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
 618         }
 619         return obj;
 620 }
 621
 622 #define MAJOR_OBJ_IS_IN_TO_SPACE(obj)   FALSE
 623
 624 /*
 625  * obj is some object.  If it's not in the major heap (i.e. if it's in
 626  * the nursery or LOS), return FALSE.  Otherwise return whether it's
 627  * been marked or copied.
 628  */
 629 static gboolean
 630 major_is_object_live (char *obj)
 631 {
 632         MSBlockInfo *block;
 633         int word, bit;
 634         mword objsize;
 635
 636         if (sgen_ptr_in_nursery (obj))
 637                 return FALSE;
 638
 639         objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 640
 641         /* LOS */
 642         if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
 643                 return FALSE;
 644
 645         /* now we know it's in a major block */
 646         block = MS_BLOCK_FOR_OBJ (obj);
 647         SGEN_ASSERT (9, !block->pinned, "block %p is pinned, BTW why is this bad?");
 648         MS_CALC_MARK_BIT (word, bit, obj);
 649         return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
 650 }
 651
 652 static gboolean
 653 major_ptr_is_in_non_pinned_space (char *ptr, char **start)
 654 {
 655         MSBlockInfo *block;
 656
 657         FOREACH_BLOCK (block) {
 658                 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) {
 659                         int count = MS_BLOCK_FREE / block->obj_size;
 660                         int i;
 661
 662                         *start = NULL;
 663                         for (i = 0; i <= count; ++i) {
 664                                 if (ptr >= MS_BLOCK_OBJ (block, i) && ptr < MS_BLOCK_OBJ (block, i + 1)) {
 665                                         *start = MS_BLOCK_OBJ (block, i);
 666                                         break;
 667                                 }
 668                         }
 669                         return !block->pinned;
 670                 }
 671         } END_FOREACH_BLOCK;
 672         return FALSE;
 673 }
 674
 675 static void
 676 major_iterate_objects (IterateObjectsFlags flags, IterateObjectCallbackFunc callback, void *data)
 677 {
 678         gboolean sweep = flags & ITERATE_OBJECTS_SWEEP;
 679         gboolean non_pinned = flags & ITERATE_OBJECTS_NON_PINNED;
 680         gboolean pinned = flags & ITERATE_OBJECTS_PINNED;
 681         MSBlockInfo *block;
 682
 683         FOREACH_BLOCK (block) {
 684                 int count = MS_BLOCK_FREE / block->obj_size;
 685                 int i;
 686
 687                 if (block->pinned && !pinned)
 688                         continue;
 689                 if (!block->pinned && !non_pinned)
 690                         continue;
 691                 if (sweep && lazy_sweep) {
 692                         sweep_block (block, FALSE);
 693                         SGEN_ASSERT (0, block->swept, "Block must be swept after sweeping");
 694                 }
 695
 696                 for (i = 0; i < count; ++i) {
 697                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 698                         if (!block->swept) {
 699                                 int word, bit;
 700                                 MS_CALC_MARK_BIT (word, bit, obj);
 701                                 if (!MS_MARK_BIT (block, word, bit))
 702                                         continue;
 703                         }
 704                         if (MS_OBJ_ALLOCED (obj, block))
 705                                 callback ((char*)obj, block->obj_size, data);
 706                 }
 707         } END_FOREACH_BLOCK;
 708 }
 709
 710 static gboolean
 711 major_is_valid_object (char *object)
 712 {
 713         MSBlockInfo *block;
 714
 715         FOREACH_BLOCK (block) {
 716                 int idx;
 717                 char *obj;
 718
 719                 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > object) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= object))
 720                         continue;
 721
 722                 idx = MS_BLOCK_OBJ_INDEX (object, block);
 723                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 724                 if (obj != object)
 725                         return FALSE;
 726                 return MS_OBJ_ALLOCED (obj, block);
 727         } END_FOREACH_BLOCK;
 728
 729         return FALSE;
 730 }
 731
 732
 733 static MonoVTable*
 734 major_describe_pointer (char *ptr)
 735 {
 736         MSBlockInfo *block;
 737
 738         FOREACH_BLOCK (block) {
 739                 int idx;
 740                 char *obj;
 741                 gboolean live;
 742                 MonoVTable *vtable;
 743                 int w, b;
 744                 gboolean marked;
 745
 746                 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > ptr) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= ptr))
 747                         continue;
 748
 749                 SGEN_LOG (0, "major-ptr (block %p sz %d pin %d ref %d)\n",
 750                         MS_BLOCK_FOR_BLOCK_INFO (block), block->obj_size, block->pinned, block->has_references);
 751
 752                 idx = MS_BLOCK_OBJ_INDEX (ptr, block);
 753                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 754                 live = MS_OBJ_ALLOCED (obj, block);
 755                 vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
 756
 757                 MS_CALC_MARK_BIT (w, b, obj);
 758                 marked = MS_MARK_BIT (block, w, b);
 759
 760                 if (obj == ptr) {
 761                         SGEN_LOG (0, "\t(");
 762                         if (live)
 763                                 SGEN_LOG (0, "object");
 764                         else
 765                                 SGEN_LOG (0, "dead-object");
 766                 } else {
 767                         if (live)
 768                                 SGEN_LOG (0, "interior-ptr offset %td", ptr - obj);
 769                         else
 770                                 SGEN_LOG (0, "dead-interior-ptr offset %td", ptr - obj);
 771                 }
 772
 773                 SGEN_LOG (0, " marked %d)\n", marked ? 1 : 0);
 774
 775                 return vtable;
 776         } END_FOREACH_BLOCK;
 777
 778         return NULL;
 779 }
 780
 781 static void
 782 major_check_scan_starts (void)
 783 {
 784 }
 785
 786 static void
 787 major_dump_heap (FILE *heap_dump_file)
 788 {
 789         MSBlockInfo *block;
 790         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
 791         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
 792         int i;
 793
 794         for (i = 0; i < num_block_obj_sizes; ++i)
 795                 slots_available [i] = slots_used [i] = 0;
 796
 797         FOREACH_BLOCK (block) {
 798                 int index = ms_find_block_obj_size_index (block->obj_size);
 799                 int count = MS_BLOCK_FREE / block->obj_size;
 800
 801                 slots_available [index] += count;
 802                 for (i = 0; i < count; ++i) {
 803                         if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
 804                                 ++slots_used [index];
 805                 }
 806         } END_FOREACH_BLOCK;
 807
 808         fprintf (heap_dump_file, "<occupancies>\n");
 809         for (i = 0; i < num_block_obj_sizes; ++i) {
 810                 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
 811                                 block_obj_sizes [i], slots_available [i], slots_used [i]);
 812         }
 813         fprintf (heap_dump_file, "</occupancies>\n");
 814
 815         FOREACH_BLOCK (block) {
 816                 int count = MS_BLOCK_FREE / block->obj_size;
 817                 int i;
 818                 int start = -1;
 819
 820                 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
 821
 822                 for (i = 0; i <= count; ++i) {
 823                         if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
 824                                 if (start < 0)
 825                                         start = i;
 826                         } else {
 827                                 if (start >= 0) {
 828                                         sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), MS_BLOCK_FOR_BLOCK_INFO (block));
 829                                         start = -1;
 830                                 }
 831                         }
 832                 }
 833
 834                 fprintf (heap_dump_file, "</section>\n");
 835         } END_FOREACH_BLOCK;
 836 }
 837
 838 #define LOAD_VTABLE     SGEN_LOAD_VTABLE
 839
 840 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,desc,block,queue) do {   \
 841                 int __word, __bit;                                      \
 842                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 843                 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
 844                         MS_SET_MARK_BIT ((block), __word, __bit);       \
 845                         if ((block)->has_references)                    \
 846                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 847                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 848                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 849                 }                                                       \
 850         } while (0)
 851 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do {           \
 852                 int __word, __bit;                                      \
 853                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 854                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj);       \
 855                 if (!MS_MARK_BIT ((block), __word, __bit)) {            \
 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_PAR_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do {       \
 864                 int __word, __bit;                                      \
 865                 gboolean __was_marked;                                  \
 866                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj);       \
 867                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 868                 MS_PAR_SET_MARK_BIT (__was_marked, (block), __word, __bit); \
 869                 if (!__was_marked) {                                    \
 870                         if ((block)->has_references)                    \
 871                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 872                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 873                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 874                 }                                                       \
 875         } while (0)
 876
 877 static void
 878 pin_major_object (char *obj, SgenGrayQueue *queue)
 879 {
 880         MSBlockInfo *block;
 881
 882 #ifdef SGEN_HAVE_CONCURRENT_MARK
 883         if (concurrent_mark)
 884                 g_assert_not_reached ();
 885 #endif
 886
 887         block = MS_BLOCK_FOR_OBJ (obj);
 888         block->has_pinned = TRUE;
 889         MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 890 }
 891
 892 #include "sgen-major-copy-object.h"
 893
 894 #ifdef SGEN_HAVE_CONCURRENT_MARK
 895 static void
 896 major_copy_or_mark_object_concurrent (void **ptr, void *obj, SgenGrayQueue *queue)
 897 {
 898         g_assert (!SGEN_OBJECT_IS_FORWARDED (obj));
 899
 900         if (!sgen_ptr_in_nursery (obj)) {
 901                 mword objsize;
 902
 903                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 904
 905                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
 906                         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 907                         MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 908                 } else {
 909                         if (sgen_los_object_is_pinned (obj))
 910                                 return;
 911
 912 #ifdef ENABLE_DTRACE
 913                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
 914                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
 915                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
 916                         }
 917 #endif
 918
 919                         sgen_los_pin_object (obj);
 920                         if (SGEN_OBJECT_HAS_REFERENCES (obj))
 921                                 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
 922                         INC_NUM_MAJOR_OBJECTS_MARKED ();
 923                 }
 924         }
 925 }
 926 #endif
 927
 928 static void
 929 major_copy_or_mark_object (void **ptr, void *obj, SgenGrayQueue *queue)
 930 {
 931         MSBlockInfo *block;
 932
 933         HEAVY_STAT (++stat_copy_object_called_major);
 934
 935         SGEN_ASSERT (9, obj, "null object from pointer %p", ptr);
 936         SGEN_ASSERT (9, current_collection_generation == GENERATION_OLD, "old gen parallel allocator called from a %d collection", current_collection_generation);
 937
 938         if (sgen_ptr_in_nursery (obj)) {
 939                 int word, bit;
 940                 char *forwarded, *old_obj;
 941
 942                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
 943                         *ptr = forwarded;
 944                         return;
 945                 }
 946                 if (SGEN_OBJECT_IS_PINNED (obj))
 947                         return;
 948
 949                 /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
 950                 if (sgen_nursery_is_to_space (obj))
 951                         return;
 952
 953                 HEAVY_STAT (++stat_objects_copied_major);
 954
 955         do_copy_object:
 956                 old_obj = obj;
 957                 obj = copy_object_no_checks (obj, queue);
 958                 if (G_UNLIKELY (old_obj == obj)) {
 959                         /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
 960                         if (!sgen_ptr_in_nursery (obj)) {
 961                                 int size_index;
 962                                 block = MS_BLOCK_FOR_OBJ (obj);
 963                                 size_index = block->obj_size_index;
 964                                 evacuate_block_obj_sizes [size_index] = FALSE;
 965                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 966                         }
 967                         return;
 968                 }
 969                 *ptr = obj;
 970
 971                 /*
 972                  * FIXME: See comment for copy_object_no_checks().  If
 973                  * we have that, we can let the allocation function
 974                  * give us the block info, too, and we won't have to
 975                  * re-fetch it.
 976                  *
 977                  * FIXME (2): We should rework this to avoid all those nursery checks.
 978                  */
 979                 /*
 980                  * For the split nursery allocator the object might
 981                  * still be in the nursery despite having being
 982                  * promoted, in which case we can't mark it.
 983                  */
 984                 if (!sgen_ptr_in_nursery (obj)) {
 985                         block = MS_BLOCK_FOR_OBJ (obj);
 986                         MS_CALC_MARK_BIT (word, bit, obj);
 987                         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p already marked", obj);
 988                         MS_SET_MARK_BIT (block, word, bit);
 989                         binary_protocol_mark (obj, (gpointer)LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
 990                 }
 991         } else {
 992                 char *forwarded;
 993                 mword objsize;
 994
 995                 /*
 996                  * If we have don't have a fixed heap we cannot know
 997                  * whether an object is in the LOS or in the small
 998                  * object major heap without checking its size.  To do
 999                  * that, however, we need to know that we actually
1000                  * have a valid object, not a forwarding pointer, so
1001                  * we have to do this check first.
1002                  */
1003                 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
1004                         *ptr = forwarded;
1005                         return;
1006                 }
1007
1008                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
1009
1010                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
1011                         int size_index;
1012                         gboolean evacuate;
1013
1014                         block = MS_BLOCK_FOR_OBJ (obj);
1015                         size_index = block->obj_size_index;
1016                         evacuate = evacuate_block_obj_sizes [size_index];
1017
1018                         if (evacuate && !block->has_pinned) {
1019                                 g_assert (!SGEN_OBJECT_IS_PINNED (obj));
1020                                 if (block->is_to_space)
1021                                         return;
1022                                 HEAVY_STAT (++stat_major_objects_evacuated);
1023                                 goto do_copy_object;
1024                         } else {
1025                                 MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
1026                         }
1027                 } else {
1028                         if (sgen_los_object_is_pinned (obj))
1029                                 return;
1030                         binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
1031
1032 #ifdef ENABLE_DTRACE
1033                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1034                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
1035                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
1036                         }
1037 #endif
1038
1039                         sgen_los_pin_object (obj);
1040                         if (SGEN_OBJECT_HAS_REFERENCES (obj))
1041                                 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
1042                 }
1043         }
1044 }
1045
1046 static void
1047 major_copy_or_mark_object_canonical (void **ptr, SgenGrayQueue *queue)
1048 {
1049         major_copy_or_mark_object (ptr, *ptr, queue);
1050 }
1051
1052 #ifdef SGEN_HAVE_CONCURRENT_MARK
1053 static void
1054 major_copy_or_mark_object_concurrent_canonical (void **ptr, SgenGrayQueue *queue)
1055 {
1056         major_copy_or_mark_object_concurrent (ptr, *ptr, queue);
1057 }
1058 #endif
1059
1060 static long long
1061 major_get_and_reset_num_major_objects_marked (void)
1062 {
1063 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
1064         long long num = num_major_objects_marked;
1065         num_major_objects_marked = 0;
1066         return num;
1067 #else
1068         return 0;
1069 #endif
1070 }
1071
1072 #include "sgen-major-scan-object.h"
1073
1074 #ifdef SGEN_HAVE_CONCURRENT_MARK
1075 #define SCAN_FOR_CONCURRENT_MARK
1076 #include "sgen-major-scan-object.h"
1077 #undef SCAN_FOR_CONCURRENT_MARK
1078 #endif
1079
1080 static void
1081 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
1082 {
1083         void **entry, **end;
1084         int last_index = -1;
1085
1086         if (block->pin_queue_first_entry == block->pin_queue_last_entry)
1087                 return;
1088
1089         block->has_pinned = TRUE;
1090
1091         entry = sgen_pinning_get_entry (block->pin_queue_first_entry);
1092         end = sgen_pinning_get_entry (block->pin_queue_last_entry);
1093
1094         for (; entry < end; ++entry) {
1095                 int index = MS_BLOCK_OBJ_INDEX (*entry, block);
1096                 char *obj;
1097                 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);
1098                 if (index == last_index)
1099                         continue;
1100                 obj = MS_BLOCK_OBJ (block, index);
1101                 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (obj, sgen_obj_get_descriptor (obj), block, queue);
1102                 last_index = index;
1103         }
1104 }
1105
1106 static inline void
1107 sweep_block_for_size (MSBlockInfo *block, int count, int obj_size)
1108 {
1109         int obj_index;
1110
1111         for (obj_index = 0; obj_index < count; ++obj_index) {
1112                 int word, bit;
1113                 void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, obj_index, obj_size);
1114
1115                 MS_CALC_MARK_BIT (word, bit, obj);
1116                 if (MS_MARK_BIT (block, word, bit)) {
1117                         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p not allocated", obj);
1118                 } else {
1119                         /* an unmarked object */
1120                         if (MS_OBJ_ALLOCED (obj, block)) {
1121                                 /*
1122                                  * FIXME: Merge consecutive
1123                                  * slots for lower reporting
1124                                  * overhead.  Maybe memset
1125                                  * will also benefit?
1126                                  */
1127                                 binary_protocol_empty (obj, obj_size);
1128                                 MONO_GC_MAJOR_SWEPT ((mword)obj, obj_size);
1129                                 memset (obj, 0, obj_size);
1130                         }
1131                         *(void**)obj = block->free_list;
1132                         block->free_list = obj;
1133                 }
1134         }
1135 }
1136
1137 /*
1138  * sweep_block:
1139  *
1140  *   Traverse BLOCK, freeing and zeroing unused objects.
1141  */
1142 static void
1143 sweep_block (MSBlockInfo *block, gboolean during_major_collection)
1144 {
1145         int count;
1146         void *reversed = NULL;
1147
1148         if (!during_major_collection)
1149                 g_assert (!sgen_concurrent_collection_in_progress ());
1150
1151         if (block->swept)
1152                 return;
1153
1154         count = MS_BLOCK_FREE / block->obj_size;
1155
1156         block->free_list = NULL;
1157
1158         /* Use inline instances specialized to constant sizes, this allows the compiler to replace the memset calls with inline code */
1159         // FIXME: Add more sizes
1160         switch (block->obj_size) {
1161         case 16:
1162                 sweep_block_for_size (block, count, 16);
1163                 break;
1164         default:
1165                 sweep_block_for_size (block, count, block->obj_size);
1166                 break;
1167         }
1168
1169         /* reset mark bits */
1170         memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1171
1172         /* Reverse free list so that it's in address order */
1173         reversed = NULL;
1174         while (block->free_list) {
1175                 void *next = *(void**)block->free_list;
1176                 *(void**)block->free_list = reversed;
1177                 reversed = block->free_list;
1178                 block->free_list = next;
1179         }
1180         block->free_list = reversed;
1181
1182         block->swept = 1;
1183 }
1184
1185 static inline int
1186 bitcount (mword d)
1187 {
1188         int count = 0;
1189
1190 #ifdef __GNUC__
1191         if (sizeof (mword) == sizeof (unsigned long))
1192                 count += __builtin_popcountl (d);
1193         else
1194                 count += __builtin_popcount (d);
1195 #else
1196         while (d) {
1197                 count ++;
1198                 d &= (d - 1);
1199         }
1200 #endif
1201         return count;
1202 }
1203
1204 static void
1205 ms_sweep (void)
1206 {
1207         int i;
1208         MSBlockInfo *block;
1209
1210         /* statistics for evacuation */
1211         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1212         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1213         int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1214
1215 #ifdef SGEN_HAVE_CONCURRENT_MARK
1216         mword total_evacuate_heap = 0;
1217         mword total_evacuate_saved = 0;
1218 #endif
1219
1220         for (i = 0; i < num_block_obj_sizes; ++i)
1221                 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1222
1223         /* clear all the free lists */
1224         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1225                 MSBlockInfo **free_blocks = free_block_lists [i];
1226                 int j;
1227                 for (j = 0; j < num_block_obj_sizes; ++j)
1228                         free_blocks [j] = NULL;
1229         }
1230
1231         /* traverse all blocks, free and zero unmarked objects */
1232         FOREACH_BLOCK (block) {
1233                 int count;
1234                 gboolean have_live = FALSE;
1235                 gboolean has_pinned;
1236                 gboolean have_free = FALSE;
1237                 int obj_size_index;
1238                 int nused = 0;
1239
1240                 obj_size_index = block->obj_size_index;
1241
1242                 has_pinned = block->has_pinned;
1243                 block->has_pinned = block->pinned;
1244
1245                 block->is_to_space = FALSE;
1246                 block->swept = 0;
1247
1248                 count = MS_BLOCK_FREE / block->obj_size;
1249
1250 #ifdef SGEN_HAVE_CONCURRENT_MARK
1251                 if (block->cardtable_mod_union) {
1252                         sgen_free_internal_dynamic (block->cardtable_mod_union, CARDS_PER_BLOCK, INTERNAL_MEM_CARDTABLE_MOD_UNION);
1253                         block->cardtable_mod_union = NULL;
1254                 }
1255 #endif
1256
1257                 /* Count marked objects in the block */
1258                 for (i = 0; i < MS_NUM_MARK_WORDS; ++i) {
1259                         nused += bitcount (block->mark_words [i]);
1260                 }
1261                 if (nused) {
1262                         have_live = TRUE;
1263                 }
1264                 if (nused < count)
1265                         have_free = TRUE;
1266
1267                 if (!lazy_sweep)
1268                         sweep_block (block, TRUE);
1269
1270                 if (have_live) {
1271                         if (!has_pinned) {
1272                                 ++num_blocks [obj_size_index];
1273                                 slots_used [obj_size_index] += nused;
1274                                 slots_available [obj_size_index] += count;
1275                         }
1276
1277                         /*
1278                          * If there are free slots in the block, add
1279                          * the block to the corresponding free list.
1280                          */
1281                         if (have_free) {
1282                                 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1283                                 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1284                                 block->next_free = free_blocks [index];
1285                                 free_blocks [index] = block;
1286                         }
1287
1288                         update_heap_boundaries_for_block (block);
1289                 } else {
1290                         /*
1291                          * Blocks without live objects are removed from the
1292                          * block list and freed.
1293                          */
1294                         DELETE_BLOCK_IN_FOREACH ();
1295
1296                         binary_protocol_empty (MS_BLOCK_OBJ (block, 0), (char*)MS_BLOCK_OBJ (block, count) - (char*)MS_BLOCK_OBJ (block, 0));
1297                         ms_free_block (block->block);
1298                         sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
1299
1300                         --num_major_sections;
1301                 }
1302         } END_FOREACH_BLOCK;
1303         sgen_pointer_queue_remove_nulls (&allocated_blocks);
1304
1305         for (i = 0; i < num_block_obj_sizes; ++i) {
1306                 float usage = (float)slots_used [i] / (float)slots_available [i];
1307                 if (num_blocks [i] > 5 && usage < evacuation_threshold) {
1308                         evacuate_block_obj_sizes [i] = TRUE;
1309                         /*
1310                         g_print ("slot size %d - %d of %d used\n",
1311                                         block_obj_sizes [i], slots_used [i], slots_available [i]);
1312                         */
1313                 } else {
1314                         evacuate_block_obj_sizes [i] = FALSE;
1315                 }
1316 #ifdef SGEN_HAVE_CONCURRENT_MARK
1317                 {
1318                         mword total_bytes = block_obj_sizes [i] * slots_available [i];
1319                         total_evacuate_heap += total_bytes;
1320                         if (evacuate_block_obj_sizes [i])
1321                                 total_evacuate_saved += total_bytes - block_obj_sizes [i] * slots_used [i];
1322                 }
1323 #endif
1324         }
1325
1326 #ifdef SGEN_HAVE_CONCURRENT_MARK
1327         want_evacuation = (float)total_evacuate_saved / (float)total_evacuate_heap > (1 - concurrent_evacuation_threshold);
1328 #endif
1329
1330         have_swept = TRUE;
1331 }
1332
1333 static void
1334 major_sweep (void)
1335 {
1336         ms_sweep ();
1337 }
1338
1339 static int count_pinned_ref;
1340 static int count_pinned_nonref;
1341 static int count_nonpinned_ref;
1342 static int count_nonpinned_nonref;
1343
1344 static void
1345 count_nonpinned_callback (char *obj, size_t size, void *data)
1346 {
1347         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1348
1349         if (vtable->klass->has_references)
1350                 ++count_nonpinned_ref;
1351         else
1352                 ++count_nonpinned_nonref;
1353 }
1354
1355 static void
1356 count_pinned_callback (char *obj, size_t size, void *data)
1357 {
1358         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1359
1360         if (vtable->klass->has_references)
1361                 ++count_pinned_ref;
1362         else
1363                 ++count_pinned_nonref;
1364 }
1365
1366 static G_GNUC_UNUSED void
1367 count_ref_nonref_objs (void)
1368 {
1369         int total;
1370
1371         count_pinned_ref = 0;
1372         count_pinned_nonref = 0;
1373         count_nonpinned_ref = 0;
1374         count_nonpinned_nonref = 0;
1375
1376         major_iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, count_nonpinned_callback, NULL);
1377         major_iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, count_pinned_callback, NULL);
1378
1379         total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1380
1381         g_print ("ref: %d pinned %d non-pinned   non-ref: %d pinned %d non-pinned  --  %.1f\n",
1382                         count_pinned_ref, count_nonpinned_ref,
1383                         count_pinned_nonref, count_nonpinned_nonref,
1384                         (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1385 }
1386
1387 static int
1388 ms_calculate_block_obj_sizes (double factor, int *arr)
1389 {
1390         double target_size = sizeof (MonoObject);
1391         int num_sizes = 0;
1392         int last_size = 0;
1393
1394         do {
1395                 int target_count = (int)ceil (MS_BLOCK_FREE / target_size);
1396                 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1397
1398                 if (size != last_size) {
1399                         if (arr)
1400                                 arr [num_sizes] = size;
1401                         ++num_sizes;
1402                         last_size = size;
1403                 }
1404
1405                 target_size *= factor;
1406         } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1407
1408         return num_sizes;
1409 }
1410
1411 /* only valid during minor collections */
1412 static mword old_num_major_sections;
1413
1414 static void
1415 major_start_nursery_collection (void)
1416 {
1417 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1418         consistency_check ();
1419 #endif
1420
1421         old_num_major_sections = num_major_sections;
1422 }
1423
1424 static void
1425 major_finish_nursery_collection (void)
1426 {
1427 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1428         consistency_check ();
1429 #endif
1430         sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1431 }
1432
1433 static void
1434 major_start_major_collection (void)
1435 {
1436         int i;
1437
1438         /* clear the free lists */
1439         for (i = 0; i < num_block_obj_sizes; ++i) {
1440                 if (!evacuate_block_obj_sizes [i])
1441                         continue;
1442
1443                 free_block_lists [0][i] = NULL;
1444                 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1445         }
1446
1447         // Sweep all unswept blocks
1448         if (lazy_sweep) {
1449                 MSBlockInfo *block;
1450
1451                 MONO_GC_SWEEP_BEGIN (GENERATION_OLD, TRUE);
1452
1453                 FOREACH_BLOCK (block) {
1454                         sweep_block (block, TRUE);
1455                 } END_FOREACH_BLOCK;
1456
1457                 MONO_GC_SWEEP_END (GENERATION_OLD, TRUE);
1458         }
1459 }
1460
1461 static void
1462 major_finish_major_collection (void)
1463 {
1464 }
1465
1466 #if SIZEOF_VOID_P != 8
1467 static int
1468 compare_pointers (const void *va, const void *vb) {
1469         char *a = *(char**)va, *b = *(char**)vb;
1470         if (a < b)
1471                 return -1;
1472         if (a > b)
1473                 return 1;
1474         return 0;
1475 }
1476 #endif
1477
1478 static void
1479 major_have_computer_minor_collection_allowance (void)
1480 {
1481         size_t section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1482
1483         g_assert (have_swept);
1484
1485 #if SIZEOF_VOID_P != 8
1486         {
1487                 int i, num_empty_blocks_orig, num_blocks, arr_length;
1488                 void *block;
1489                 void **empty_block_arr;
1490                 void **rebuild_next;
1491
1492 #ifdef TARGET_WIN32
1493                 /*
1494                  * sgen_free_os_memory () asserts in mono_vfree () because windows doesn't like freeing the middle of
1495                  * a VirtualAlloc ()-ed block.
1496                  */
1497                 return;
1498 #endif
1499
1500                 if (num_empty_blocks <= section_reserve)
1501                         return;
1502                 SGEN_ASSERT (0, num_empty_blocks > 0, "section reserve can't be negative");
1503
1504                 num_empty_blocks_orig = num_empty_blocks;
1505                 empty_block_arr = (void**)sgen_alloc_internal_dynamic (sizeof (void*) * num_empty_blocks_orig,
1506                                 INTERNAL_MEM_MS_BLOCK_INFO_SORT, FALSE);
1507                 if (!empty_block_arr)
1508                         goto fallback;
1509
1510                 i = 0;
1511                 for (block = empty_blocks; block; block = *(void**)block)
1512                         empty_block_arr [i++] = block;
1513                 SGEN_ASSERT (0, i == num_empty_blocks, "empty block count wrong");
1514
1515                 sgen_qsort (empty_block_arr, num_empty_blocks, sizeof (void*), compare_pointers);
1516
1517                 /*
1518                  * We iterate over the free blocks, trying to find MS_BLOCK_ALLOC_NUM
1519                  * contiguous ones.  If we do, we free them.  If that's not enough to get to
1520                  * section_reserve, we halve the number of contiguous blocks we're looking
1521                  * for and have another go, until we're done with looking for pairs of
1522                  * blocks, at which point we give up and go to the fallback.
1523                  */
1524                 arr_length = num_empty_blocks_orig;
1525                 num_blocks = MS_BLOCK_ALLOC_NUM;
1526                 while (num_empty_blocks > section_reserve && num_blocks > 1) {
1527                         int first = -1;
1528                         int dest = 0;
1529
1530                         dest = 0;
1531                         for (i = 0; i < arr_length; ++i) {
1532                                 int d = dest;
1533                                 void *block = empty_block_arr [i];
1534                                 SGEN_ASSERT (0, block, "we're not shifting correctly");
1535                                 if (i != dest) {
1536                                         empty_block_arr [dest] = block;
1537                                         /*
1538                                          * This is not strictly necessary, but we're
1539                                          * cautious.
1540                                          */
1541                                         empty_block_arr [i] = NULL;
1542                                 }
1543                                 ++dest;
1544
1545                                 if (first < 0) {
1546                                         first = d;
1547                                         continue;
1548                                 }
1549
1550                                 SGEN_ASSERT (0, first >= 0 && d > first, "algorithm is wrong");
1551
1552                                 if ((char*)block != ((char*)empty_block_arr [d-1]) + MS_BLOCK_SIZE) {
1553                                         first = d;
1554                                         continue;
1555                                 }
1556
1557                                 if (d + 1 - first == num_blocks) {
1558                                         /*
1559                                          * We found num_blocks contiguous blocks.  Free them
1560                                          * and null their array entries.  As an optimization
1561                                          * we could, instead of nulling the entries, shift
1562                                          * the following entries over to the left, while
1563                                          * we're iterating.
1564                                          */
1565                                         int j;
1566                                         sgen_free_os_memory (empty_block_arr [first], MS_BLOCK_SIZE * num_blocks, SGEN_ALLOC_HEAP);
1567                                         for (j = first; j <= d; ++j)
1568                                                 empty_block_arr [j] = NULL;
1569                                         dest = first;
1570                                         first = -1;
1571
1572                                         num_empty_blocks -= num_blocks;
1573
1574                                         stat_major_blocks_freed += num_blocks;
1575                                         if (num_blocks == MS_BLOCK_ALLOC_NUM)
1576                                                 stat_major_blocks_freed_ideal += num_blocks;
1577                                         else
1578                                                 stat_major_blocks_freed_less_ideal += num_blocks;
1579
1580                                 }
1581                         }
1582
1583                         SGEN_ASSERT (0, dest <= i && dest <= arr_length, "array length is off");
1584                         arr_length = dest;
1585                         SGEN_ASSERT (0, arr_length == num_empty_blocks, "array length is off");
1586
1587                         num_blocks >>= 1;
1588                 }
1589
1590                 /* rebuild empty_blocks free list */
1591                 rebuild_next = (void**)&empty_blocks;
1592                 for (i = 0; i < arr_length; ++i) {
1593                         void *block = empty_block_arr [i];
1594                         SGEN_ASSERT (0, block, "we're missing blocks");
1595                         *rebuild_next = block;
1596                         rebuild_next = (void**)block;
1597                 }
1598                 *rebuild_next = NULL;
1599
1600                 /* free array */
1601                 sgen_free_internal_dynamic (empty_block_arr, sizeof (void*) * num_empty_blocks_orig, INTERNAL_MEM_MS_BLOCK_INFO_SORT);
1602         }
1603
1604         SGEN_ASSERT (0, num_empty_blocks >= 0, "we freed more blocks than we had in the first place?");
1605
1606  fallback:
1607         /*
1608          * This is our threshold.  If there's not more empty than used blocks, we won't
1609          * release uncontiguous blocks, in fear of fragmenting the address space.
1610          */
1611         if (num_empty_blocks <= num_major_sections)
1612                 return;
1613 #endif
1614
1615         while (num_empty_blocks > section_reserve) {
1616                 void *next = *(void**)empty_blocks;
1617                 sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP);
1618                 empty_blocks = next;
1619                 /*
1620                  * Needs not be atomic because this is running
1621                  * single-threaded.
1622                  */
1623                 --num_empty_blocks;
1624
1625                 ++stat_major_blocks_freed;
1626 #if SIZEOF_VOID_P != 8
1627                 ++stat_major_blocks_freed_individual;
1628 #endif
1629         }
1630 }
1631
1632 static void
1633 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
1634 {
1635         MSBlockInfo *block;
1636
1637         FOREACH_BLOCK (block) {
1638                 sgen_find_optimized_pin_queue_area (MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SKIP, MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE,
1639                                 &block->pin_queue_first_entry, &block->pin_queue_last_entry);
1640         } END_FOREACH_BLOCK;
1641 }
1642
1643 static void
1644 major_pin_objects (SgenGrayQueue *queue)
1645 {
1646         MSBlockInfo *block;
1647
1648         FOREACH_BLOCK (block) {
1649                 mark_pinned_objects_in_block (block, queue);
1650         } END_FOREACH_BLOCK;
1651 }
1652
1653 static void
1654 major_init_to_space (void)
1655 {
1656 }
1657
1658 static void
1659 major_report_pinned_memory_usage (void)
1660 {
1661         g_assert_not_reached ();
1662 }
1663
1664 static gint64
1665 major_get_used_size (void)
1666 {
1667         gint64 size = 0;
1668         MSBlockInfo *block;
1669
1670         FOREACH_BLOCK (block) {
1671                 int count = MS_BLOCK_FREE / block->obj_size;
1672                 void **iter;
1673                 size += count * block->obj_size;
1674                 for (iter = block->free_list; iter; iter = (void**)*iter)
1675                         size -= block->obj_size;
1676         } END_FOREACH_BLOCK;
1677
1678         return size;
1679 }
1680
1681 static size_t
1682 get_num_major_sections (void)
1683 {
1684         return num_major_sections;
1685 }
1686
1687 static gboolean
1688 major_handle_gc_param (const char *opt)
1689 {
1690         if (g_str_has_prefix (opt, "evacuation-threshold=")) {
1691                 const char *arg = strchr (opt, '=') + 1;
1692                 int percentage = atoi (arg);
1693                 if (percentage < 0 || percentage > 100) {
1694                         fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
1695                         exit (1);
1696                 }
1697                 evacuation_threshold = (float)percentage / 100.0f;
1698                 return TRUE;
1699         } else if (!strcmp (opt, "lazy-sweep")) {
1700                 lazy_sweep = TRUE;
1701                 return TRUE;
1702         } else if (!strcmp (opt, "no-lazy-sweep")) {
1703                 lazy_sweep = FALSE;
1704                 return TRUE;
1705         }
1706
1707         return FALSE;
1708 }
1709
1710 static void
1711 major_print_gc_param_usage (void)
1712 {
1713         fprintf (stderr,
1714                         ""
1715                         "  evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
1716                         "  (no-)lazy-sweep\n"
1717                         );
1718 }
1719
1720 static void
1721 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
1722 {
1723         MSBlockInfo *block;
1724         gboolean has_references;
1725
1726         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
1727                 if (has_references)
1728                         callback ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE);
1729         } END_FOREACH_BLOCK;
1730 }
1731
1732 #ifdef HEAVY_STATISTICS
1733 extern long long marked_cards;
1734 extern long long scanned_cards;
1735 extern long long scanned_objects;
1736 extern long long remarked_cards;
1737 #endif
1738
1739 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
1740 /*
1741  * MS blocks are 16K aligned.
1742  * Cardtables are 4K aligned, at least.
1743  * This means that the cardtable of a given block is 32 bytes aligned.
1744  */
1745 static guint8*
1746 initial_skip_card (guint8 *card_data)
1747 {
1748         mword *cards = (mword*)card_data;
1749         mword card;
1750         int i;
1751         for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
1752                 card = cards [i];
1753                 if (card)
1754                         break;
1755         }
1756
1757         if (i == CARD_WORDS_PER_BLOCK)
1758                 return card_data + CARDS_PER_BLOCK;
1759
1760 #if defined(__i386__) && defined(__GNUC__)
1761         return card_data + i * 4 +  (__builtin_ffs (card) - 1) / 8;
1762 #elif defined(__x86_64__) && defined(__GNUC__)
1763         return card_data + i * 8 +  (__builtin_ffsll (card) - 1) / 8;
1764 #elif defined(__s390x__) && defined(__GNUC__)
1765         return card_data + i * 8 +  (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1766 #else
1767         for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
1768                 if (card_data [i])
1769                         return &card_data [i];
1770         }
1771         return card_data;
1772 #endif
1773 }
1774
1775
1776 static G_GNUC_UNUSED guint8*
1777 skip_card (guint8 *card_data, guint8 *card_data_end)
1778 {
1779         while (card_data < card_data_end && !*card_data)
1780                 ++card_data;
1781         return card_data;
1782 }
1783
1784 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
1785 #define MS_BLOCK_OBJ_FAST(b,os,i)                       ((b) + MS_BLOCK_SKIP + (os) * (i))
1786 #define MS_OBJ_ALLOCED_FAST(o,b)                (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
1787
1788 static void
1789 major_scan_card_table (gboolean mod_union, SgenGrayQueue *queue)
1790 {
1791         MSBlockInfo *block;
1792         gboolean has_references;
1793         ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
1794
1795 #ifdef SGEN_HAVE_CONCURRENT_MARK
1796         if (!concurrent_mark)
1797                 g_assert (!mod_union);
1798 #else
1799         g_assert (!mod_union);
1800 #endif
1801
1802         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
1803                 int block_obj_size;
1804                 char *block_start;
1805
1806                 if (!has_references)
1807                         continue;
1808
1809                 block_obj_size = block->obj_size;
1810                 block_start = MS_BLOCK_FOR_BLOCK_INFO (block);
1811
1812                 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
1813                         guint8 *cards;
1814 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
1815                         guint8 cards_data [CARDS_PER_BLOCK];
1816 #endif
1817                         char *obj, *end, *base;
1818
1819                         if (mod_union) {
1820 #ifdef SGEN_HAVE_CONCURRENT_MARK
1821                                 cards = block->cardtable_mod_union;
1822                                 /*
1823                                  * This happens when the nursery
1824                                  * collection that precedes finishing
1825                                  * the concurrent collection allocates
1826                                  * new major blocks.
1827                                  */
1828                                 if (!cards)
1829                                         continue;
1830 #endif
1831                         } else {
1832                         /*We can avoid the extra copy since the remark cardtable was cleaned before */
1833 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1834                                 cards = sgen_card_table_get_card_scan_address ((mword)block_start);
1835 #else
1836                                 cards = cards_data;
1837                                 if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
1838                                         continue;
1839 #endif
1840                         }
1841
1842                         obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
1843                         end = block_start + MS_BLOCK_SIZE;
1844                         base = sgen_card_table_align_pointer (obj);
1845
1846                         while (obj < end) {
1847                                 size_t card_offset;
1848
1849                                 if (!block->swept)
1850                                         sweep_block (block, FALSE);
1851
1852                                 if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
1853                                         goto next_large;
1854
1855                                 if (mod_union) {
1856                                         /* FIXME: do this more efficiently */
1857                                         int w, b;
1858                                         MS_CALC_MARK_BIT (w, b, obj);
1859                                         if (!MS_MARK_BIT (block, w, b))
1860                                                 goto next_large;
1861                                 }
1862
1863                                 card_offset = (obj - base) >> CARD_BITS;
1864                                 sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, mod_union, queue);
1865
1866                         next_large:
1867                                 obj += block_obj_size;
1868                         }
1869                 } else {
1870                         guint8 *card_data, *card_base;
1871                         guint8 *card_data_end;
1872
1873                         /*
1874                          * This is safe in face of card aliasing for the following reason:
1875                          *
1876                          * Major blocks are 16k aligned, or 32 cards aligned.
1877                          * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
1878                          * sizes, they won't overflow the cardtable overlap modulus.
1879                          */
1880                         if (mod_union) {
1881 #ifdef SGEN_HAVE_CONCURRENT_MARK
1882                                 card_data = card_base = block->cardtable_mod_union;
1883                                 /*
1884                                  * This happens when the nursery
1885                                  * collection that precedes finishing
1886                                  * the concurrent collection allocates
1887                                  * new major blocks.
1888                                  */
1889                                 if (!card_data)
1890                                         continue;
1891 #else
1892                                 g_assert_not_reached ();
1893                                 card_data = NULL;
1894 #endif
1895                         } else {
1896                                 card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
1897                         }
1898                         card_data_end = card_data + CARDS_PER_BLOCK;
1899
1900                         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)) {
1901                                 size_t index;
1902                                 size_t idx = card_data - card_base;
1903                                 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
1904                                 char *end = start + CARD_SIZE_IN_BYTES;
1905                                 char *first_obj, *obj;
1906
1907                                 HEAVY_STAT (++scanned_cards);
1908
1909                                 if (!*card_data)
1910                                         continue;
1911
1912                                 if (!block->swept)
1913                                         sweep_block (block, FALSE);
1914
1915                                 HEAVY_STAT (++marked_cards);
1916
1917                                 sgen_card_table_prepare_card_for_scanning (card_data);
1918
1919                                 if (idx == 0)
1920                                         index = 0;
1921                                 else
1922                                         index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
1923
1924                                 obj = first_obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
1925                                 while (obj < end) {
1926                                         if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
1927                                                 goto next_small;
1928
1929                                         if (mod_union) {
1930                                                 /* FIXME: do this more efficiently */
1931                                                 int w, b;
1932                                                 MS_CALC_MARK_BIT (w, b, obj);
1933                                                 if (!MS_MARK_BIT (block, w, b))
1934                                                         goto next_small;
1935                                         }
1936
1937                                         HEAVY_STAT (++scanned_objects);
1938                                         scan_func (obj, sgen_obj_get_descriptor (obj), queue);
1939                                 next_small:
1940                                         obj += block_obj_size;
1941                                 }
1942                                 HEAVY_STAT (if (*card_data) ++remarked_cards);
1943                                 binary_protocol_card_scan (first_obj, obj - first_obj);
1944                         }
1945                 }
1946         } END_FOREACH_BLOCK;
1947 }
1948
1949 static void
1950 major_count_cards (long long *num_total_cards, long long *num_marked_cards)
1951 {
1952         MSBlockInfo *block;
1953         gboolean has_references;
1954         long long total_cards = 0;
1955         long long marked_cards = 0;
1956
1957         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
1958                 guint8 *cards = sgen_card_table_get_card_scan_address ((mword) MS_BLOCK_FOR_BLOCK_INFO (block));
1959                 int i;
1960
1961                 if (!has_references)
1962                         continue;
1963
1964                 total_cards += CARDS_PER_BLOCK;
1965                 for (i = 0; i < CARDS_PER_BLOCK; ++i) {
1966                         if (cards [i])
1967                                 ++marked_cards;
1968                 }
1969         } END_FOREACH_BLOCK;
1970
1971         *num_total_cards = total_cards;
1972         *num_marked_cards = marked_cards;
1973 }
1974
1975 #ifdef SGEN_HAVE_CONCURRENT_MARK
1976 static void
1977 update_cardtable_mod_union (void)
1978 {
1979         MSBlockInfo *block;
1980
1981         FOREACH_BLOCK (block) {
1982                 size_t num_cards;
1983
1984                 block->cardtable_mod_union = sgen_card_table_update_mod_union (block->cardtable_mod_union,
1985                                 MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE, &num_cards);
1986
1987                 SGEN_ASSERT (0, num_cards == CARDS_PER_BLOCK, "Number of cards calculation is wrong");
1988         } END_FOREACH_BLOCK;
1989 }
1990
1991 static guint8*
1992 major_get_cardtable_mod_union_for_object (char *obj)
1993 {
1994         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1995         return &block->cardtable_mod_union [(obj - (char*)sgen_card_table_align_pointer (MS_BLOCK_FOR_BLOCK_INFO (block))) >> CARD_BITS];
1996 }
1997 #endif
1998
1999 static void
2000 alloc_free_block_lists (MSBlockInfo ***lists)
2001 {
2002         int i;
2003         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
2004                 lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2005 }
2006
2007 #undef pthread_create
2008
2009 static void
2010 post_param_init (SgenMajorCollector *collector)
2011 {
2012         collector->sweeps_lazily = lazy_sweep;
2013 }
2014
2015 #ifdef SGEN_HAVE_CONCURRENT_MARK
2016 static void
2017 sgen_marksweep_init_internal (SgenMajorCollector *collector, gboolean is_concurrent)
2018 #else // SGEN_HAVE_CONCURRENT_MARK
2019 #error unknown configuration
2020 #endif // SGEN_HAVE_CONCURRENT_MARK
2021 {
2022         int i;
2023
2024         sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
2025
2026         num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
2027         block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2028         ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
2029
2030         evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
2031         for (i = 0; i < num_block_obj_sizes; ++i)
2032                 evacuate_block_obj_sizes [i] = FALSE;
2033
2034         /*
2035         {
2036                 int i;
2037                 g_print ("block object sizes:\n");
2038                 for (i = 0; i < num_block_obj_sizes; ++i)
2039                         g_print ("%d\n", block_obj_sizes [i]);
2040         }
2041         */
2042
2043         alloc_free_block_lists (free_block_lists);
2044
2045         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
2046                 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
2047         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
2048                 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
2049
2050         mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
2051         mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
2052         mono_counters_register ("# major blocks lazy swept", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_lazy_swept);
2053         mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
2054 #if SIZEOF_VOID_P != 8
2055         mono_counters_register ("# major blocks freed ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_ideal);
2056         mono_counters_register ("# major blocks freed less ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_less_ideal);
2057         mono_counters_register ("# major blocks freed individually", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed_individual);
2058         mono_counters_register ("# major blocks allocated less ideally", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced_less_ideal);
2059 #endif
2060
2061         collector->section_size = MAJOR_SECTION_SIZE;
2062
2063 #ifdef SGEN_HAVE_CONCURRENT_MARK
2064         concurrent_mark = is_concurrent;
2065         if (is_concurrent) {
2066                 collector->is_concurrent = TRUE;
2067                 collector->want_synchronous_collection = &want_evacuation;
2068         } else
2069 #endif
2070         {
2071                 collector->is_concurrent = FALSE;
2072                 collector->want_synchronous_collection = NULL;
2073         }
2074         collector->get_and_reset_num_major_objects_marked = major_get_and_reset_num_major_objects_marked;
2075         collector->supports_cardtable = TRUE;
2076
2077         collector->have_swept = &have_swept;
2078
2079         collector->alloc_heap = major_alloc_heap;
2080         collector->is_object_live = major_is_object_live;
2081         collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2082         collector->alloc_degraded = major_alloc_degraded;
2083
2084         collector->alloc_object = major_alloc_object;
2085         collector->free_pinned_object = free_pinned_object;
2086         collector->iterate_objects = major_iterate_objects;
2087         collector->free_non_pinned_object = major_free_non_pinned_object;
2088         collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2089         collector->pin_objects = major_pin_objects;
2090         collector->pin_major_object = pin_major_object;
2091         collector->scan_card_table = major_scan_card_table;
2092         collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2093 #ifdef SGEN_HAVE_CONCURRENT_MARK
2094         if (is_concurrent) {
2095                 collector->update_cardtable_mod_union = update_cardtable_mod_union;
2096                 collector->get_cardtable_mod_union_for_object = major_get_cardtable_mod_union_for_object;
2097         }
2098 #endif
2099         collector->init_to_space = major_init_to_space;
2100         collector->sweep = major_sweep;
2101         collector->check_scan_starts = major_check_scan_starts;
2102         collector->dump_heap = major_dump_heap;
2103         collector->get_used_size = major_get_used_size;
2104         collector->start_nursery_collection = major_start_nursery_collection;
2105         collector->finish_nursery_collection = major_finish_nursery_collection;
2106         collector->start_major_collection = major_start_major_collection;
2107         collector->finish_major_collection = major_finish_major_collection;
2108         collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2109         collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2110         collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2111         collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2112         collector->get_num_major_sections = get_num_major_sections;
2113         collector->handle_gc_param = major_handle_gc_param;
2114         collector->print_gc_param_usage = major_print_gc_param_usage;
2115         collector->post_param_init = post_param_init;
2116         collector->is_valid_object = major_is_valid_object;
2117         collector->describe_pointer = major_describe_pointer;
2118         collector->count_cards = major_count_cards;
2119
2120         collector->major_ops.copy_or_mark_object = major_copy_or_mark_object_canonical;
2121         collector->major_ops.scan_object = major_scan_object;
2122 #ifdef SGEN_HAVE_CONCURRENT_MARK
2123         if (is_concurrent) {
2124                 collector->major_concurrent_ops.copy_or_mark_object = major_copy_or_mark_object_concurrent_canonical;
2125                 collector->major_concurrent_ops.scan_object = major_scan_object_concurrent;
2126                 collector->major_concurrent_ops.scan_vtype = major_scan_vtype_concurrent;
2127         }
2128 #endif
2129
2130         /*cardtable requires major pages to be 8 cards aligned*/
2131         g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);
2132 }
2133
2134 #ifdef SGEN_HAVE_CONCURRENT_MARK
2135 void
2136 sgen_marksweep_init (SgenMajorCollector *collector)
2137 {
2138         sgen_marksweep_init_internal (collector, FALSE);
2139 }
2140
2141 void
2142 sgen_marksweep_conc_init (SgenMajorCollector *collector)
2143 {
2144         sgen_marksweep_init_internal (collector, TRUE);
2145 }
2146 #endif
2147
2148 #endif