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 #if defined(ARCH_MIN_MS_BLOCK_SIZE) && defined(ARCH_MIN_MS_BLOCK_SIZE_SHIFT)
  50 #define MS_BLOCK_SIZE   ARCH_MIN_MS_BLOCK_SIZE
  51 #define MS_BLOCK_SIZE_SHIFT     ARCH_MIN_MS_BLOCK_SIZE_SHIFT
  52 #else
  53 #define MS_BLOCK_SIZE_SHIFT     14      /* INT FASTENABLE */
  54 #define MS_BLOCK_SIZE           (1 << MS_BLOCK_SIZE_SHIFT)
  55 #endif
  56 #define MAJOR_SECTION_SIZE      MS_BLOCK_SIZE
  57 #define CARDS_PER_BLOCK (MS_BLOCK_SIZE / CARD_SIZE_IN_BYTES)
  58
  59 /*
  60  * Don't allocate single blocks, but alloc a contingent of this many
  61  * blocks in one swoop.  This must be a power of two.
  62  */
  63 #define MS_BLOCK_ALLOC_NUM      32
  64
  65 /*
  66  * Number of bytes before the first object in a block.  At the start
  67  * of a block is the MSBlockHeader, then opional padding, then come
  68  * the objects, so this must be >= sizeof (MSBlockHeader).
  69  */
  70 #define MS_BLOCK_SKIP   ((sizeof (MSBlockHeader) + 15) & ~15)
  71
  72 #define MS_BLOCK_FREE   (MS_BLOCK_SIZE - MS_BLOCK_SKIP)
  73
  74 #define MS_NUM_MARK_WORDS       ((MS_BLOCK_SIZE / SGEN_ALLOC_ALIGN + sizeof (mword) * 8 - 1) / (sizeof (mword) * 8))
  75
  76 typedef struct _MSBlockInfo MSBlockInfo;
  77 struct _MSBlockInfo {
  78         int obj_size;
  79         int obj_size_index;
  80         unsigned int pinned : 1;
  81         unsigned int has_references : 1;
  82         unsigned int has_pinned : 1;    /* means cannot evacuate */
  83         unsigned int is_to_space : 1;
  84         unsigned int swept : 1;
  85         void **free_list;
  86         MSBlockInfo *next_free;
  87         size_t pin_queue_first_entry;
  88         size_t pin_queue_last_entry;
  89 #ifdef SGEN_HAVE_CONCURRENT_MARK
  90         guint8 *cardtable_mod_union;
  91 #endif
  92         mword mark_words [MS_NUM_MARK_WORDS];
  93 };
  94
  95 #define MS_BLOCK_FOR_BLOCK_INFO(b)      ((char*)(b))
  96
  97 #define MS_BLOCK_OBJ(b,i)               (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (b)->obj_size * (i))
  98 #define MS_BLOCK_OBJ_FOR_SIZE(b,i,obj_size)             (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP + (obj_size) * (i))
  99 #define MS_BLOCK_DATA_FOR_OBJ(o)        ((char*)((mword)(o) & ~(mword)(MS_BLOCK_SIZE - 1)))
 100
 101 typedef struct {
 102         MSBlockInfo info;
 103 } MSBlockHeader;
 104
 105 #define MS_BLOCK_FOR_OBJ(o)             (&((MSBlockHeader*)MS_BLOCK_DATA_FOR_OBJ ((o)))->info)
 106
 107 /* object index will always be small */
 108 #define MS_BLOCK_OBJ_INDEX(o,b) ((int)(((char*)(o) - (MS_BLOCK_FOR_BLOCK_INFO(b) + MS_BLOCK_SKIP)) / (b)->obj_size))
 109
 110 //casting to int is fine since blocks are 32k
 111 #define MS_CALC_MARK_BIT(w,b,o)         do {                            \
 112                 int i = ((int)((char*)(o) - MS_BLOCK_DATA_FOR_OBJ ((o)))) >> SGEN_ALLOC_ALIGN_BITS; \
 113                 if (sizeof (mword) == 4) {                              \
 114                         (w) = i >> 5;                                   \
 115                         (b) = i & 31;                                   \
 116                 } else {                                                \
 117                         (w) = i >> 6;                                   \
 118                         (b) = i & 63;                                   \
 119                 }                                                       \
 120         } while (0)
 121
 122 #define MS_MARK_BIT(bl,w,b)     ((bl)->mark_words [(w)] & (ONE_P << (b)))
 123 #define MS_SET_MARK_BIT(bl,w,b) ((bl)->mark_words [(w)] |= (ONE_P << (b)))
 124
 125 #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))
 126
 127 #define MS_BLOCK_OBJ_SIZE_FACTOR        (pow (2.0, 1.0 / 3))
 128
 129 /*
 130  * This way we can lookup block object size indexes for sizes up to
 131  * 256 bytes with a single load.
 132  */
 133 #define MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES      32
 134
 135 static int *block_obj_sizes;
 136 static int num_block_obj_sizes;
 137 static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
 138
 139 #define MS_BLOCK_FLAG_PINNED    1
 140 #define MS_BLOCK_FLAG_REFS      2
 141
 142 #define MS_BLOCK_TYPE_MAX       4
 143
 144 static gboolean *evacuate_block_obj_sizes;
 145 static float evacuation_threshold = 0.666f;
 146 #ifdef SGEN_HAVE_CONCURRENT_MARK
 147 static float concurrent_evacuation_threshold = 0.666f;
 148 static gboolean want_evacuation = FALSE;
 149 #endif
 150
 151 static gboolean lazy_sweep = TRUE;
 152 static gboolean have_swept;
 153
 154 #ifdef SGEN_HAVE_CONCURRENT_MARK
 155 static gboolean concurrent_mark;
 156 #endif
 157
 158 #define BLOCK_IS_TAGGED_HAS_REFERENCES(bl)      SGEN_POINTER_IS_TAGGED_1 ((bl))
 159 #define BLOCK_TAG_HAS_REFERENCES(bl)            SGEN_POINTER_TAG_1 ((bl))
 160 #define BLOCK_UNTAG_HAS_REFERENCES(bl)          SGEN_POINTER_UNTAG_1 ((bl))
 161
 162 #define BLOCK_TAG(bl)   ((bl)->has_references ? BLOCK_TAG_HAS_REFERENCES ((bl)) : (bl))
 163
 164 /* all allocated blocks in the system */
 165 static SgenPointerQueue allocated_blocks;
 166
 167 /* non-allocated block free-list */
 168 static void *empty_blocks = NULL;
 169 static size_t num_empty_blocks = 0;
 170
 171 #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]);
 172 #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));
 173 #define END_FOREACH_BLOCK       } }
 174 #define DELETE_BLOCK_IN_FOREACH()       (allocated_blocks.data [__index] = NULL)
 175
 176 static size_t num_major_sections = 0;
 177 /* one free block list for each block object size */
 178 static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
 179
 180 static guint64 stat_major_blocks_alloced = 0;
 181 static guint64 stat_major_blocks_freed = 0;
 182 static guint64 stat_major_blocks_lazy_swept = 0;
 183 static guint64 stat_major_objects_evacuated = 0;
 184
 185 #if SIZEOF_VOID_P != 8
 186 static guint64 stat_major_blocks_freed_ideal = 0;
 187 static guint64 stat_major_blocks_freed_less_ideal = 0;
 188 static guint64 stat_major_blocks_freed_individual = 0;
 189 static guint64 stat_major_blocks_alloced_less_ideal = 0;
 190 #endif
 191
 192 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
 193 static guint64 num_major_objects_marked = 0;
 194 #define INC_NUM_MAJOR_OBJECTS_MARKED()  (++num_major_objects_marked)
 195 #else
 196 #define INC_NUM_MAJOR_OBJECTS_MARKED()
 197 #endif
 198
 199 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
 200 static mono_mutex_t scanned_objects_list_lock;
 201 static SgenPointerQueue scanned_objects_list;
 202
 203 static void
 204 add_scanned_object (void *ptr)
 205 {
 206         if (!binary_protocol_is_enabled ())
 207                 return;
 208
 209         mono_mutex_lock (&scanned_objects_list_lock);
 210         sgen_pointer_queue_add (&scanned_objects_list, ptr);
 211         mono_mutex_unlock (&scanned_objects_list_lock);
 212 }
 213 #endif
 214
 215 static void
 216 sweep_block (MSBlockInfo *block, gboolean during_major_collection);
 217
 218 static int
 219 ms_find_block_obj_size_index (size_t size)
 220 {
 221         int i;
 222         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);
 223         for (i = 0; i < num_block_obj_sizes; ++i)
 224                 if (block_obj_sizes [i] >= size)
 225                         return i;
 226         g_error ("no object of size %d\n", size);
 227 }
 228
 229 #define FREE_BLOCKS_FROM(lists,p,r)     (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
 230 #define FREE_BLOCKS(p,r)                (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
 231
 232 #define MS_BLOCK_OBJ_SIZE_INDEX(s)                              \
 233         (((s)+7)>>3 < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES ?      \
 234          fast_block_obj_size_indexes [((s)+7)>>3] :             \
 235          ms_find_block_obj_size_index ((s)))
 236
 237 static void*
 238 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 239 {
 240         char *start;
 241         if (nursery_align)
 242                 start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 243         else
 244                 start = sgen_alloc_os_memory (nursery_size, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE, "nursery");
 245
 246         return start;
 247 }
 248
 249 static void
 250 update_heap_boundaries_for_block (MSBlockInfo *block)
 251 {
 252         sgen_update_heap_boundaries ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), (mword)MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE);
 253 }
 254
 255 static void*
 256 ms_get_empty_block (void)
 257 {
 258         char *p;
 259         int i;
 260         void *block, *empty, *next;
 261
 262  retry:
 263         if (!empty_blocks) {
 264                 /*
 265                  * We try allocating MS_BLOCK_ALLOC_NUM blocks first.  If that's
 266                  * unsuccessful, we halve the number of blocks and try again, until we're at
 267                  * 1.  If that doesn't work, either, we assert.
 268                  */
 269                 int alloc_num = MS_BLOCK_ALLOC_NUM;
 270                 for (;;) {
 271                         p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * alloc_num, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP | SGEN_ALLOC_ACTIVATE,
 272                                         alloc_num == 1 ? "major heap section" : NULL);
 273                         if (p)
 274                                 break;
 275                         alloc_num >>= 1;
 276                 }
 277
 278                 for (i = 0; i < alloc_num; ++i) {
 279                         block = p;
 280                         /*
 281                          * We do the free list update one after the
 282                          * other so that other threads can use the new
 283                          * blocks as quickly as possible.
 284                          */
 285                         do {
 286                                 empty = empty_blocks;
 287                                 *(void**)block = empty;
 288                         } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
 289                         p += MS_BLOCK_SIZE;
 290                 }
 291
 292                 SGEN_ATOMIC_ADD_P (num_empty_blocks, alloc_num);
 293
 294                 stat_major_blocks_alloced += alloc_num;
 295 #if SIZEOF_VOID_P != 8
 296                 if (alloc_num != MS_BLOCK_ALLOC_NUM)
 297                         stat_major_blocks_alloced_less_ideal += alloc_num;
 298 #endif
 299         }
 300
 301         do {
 302                 empty = empty_blocks;
 303                 if (!empty)
 304                         goto retry;
 305                 block = empty;
 306                 next = *(void**)block;
 307         } while (SGEN_CAS_PTR (&empty_blocks, next, empty) != empty);
 308
 309         SGEN_ATOMIC_ADD_P (num_empty_blocks, -1);
 310
 311         *(void**)block = NULL;
 312
 313         g_assert (!((mword)block & (MS_BLOCK_SIZE - 1)));
 314
 315         return block;
 316 }
 317
 318 static void
 319 ms_free_block (void *block)
 320 {
 321         void *empty;
 322
 323         sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 324         memset (block, 0, MS_BLOCK_SIZE);
 325
 326         do {
 327                 empty = empty_blocks;
 328                 *(void**)block = empty;
 329         } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
 330
 331         SGEN_ATOMIC_ADD_P (num_empty_blocks, 1);
 332 }
 333
 334 //#define MARKSWEEP_CONSISTENCY_CHECK
 335
 336 #ifdef MARKSWEEP_CONSISTENCY_CHECK
 337 static void
 338 check_block_free_list (MSBlockInfo *block, int size, gboolean pinned)
 339 {
 340         MSBlockInfo *b;
 341
 342         for (; block; block = block->next_free) {
 343                 g_assert (block->obj_size == size);
 344                 g_assert ((pinned && block->pinned) || (!pinned && !block->pinned));
 345
 346                 /* blocks in the free lists must have at least
 347                    one free slot */
 348                 if (block->swept)
 349                         g_assert (block->free_list);
 350
 351                 /* the block must be in the allocated_blocks array */
 352                 g_assert (sgen_pointer_queue_find (&allocated_blocks, BLOCK_TAG (block)) != (size_t)-1);
 353         }
 354 }
 355
 356 static void
 357 check_empty_blocks (void)
 358 {
 359         void *p;
 360         size_t i = 0;
 361         for (p = empty_blocks; p; p = *(void**)p)
 362                 ++i;
 363         g_assert (i == num_empty_blocks);
 364 }
 365
 366 static void
 367 consistency_check (void)
 368 {
 369         MSBlockInfo *block;
 370         int i;
 371
 372         /* check all blocks */
 373         FOREACH_BLOCK (block) {
 374                 int count = MS_BLOCK_FREE / block->obj_size;
 375                 int num_free = 0;
 376                 void **free;
 377
 378                 /* check block header */
 379                 g_assert (((MSBlockHeader*)block->block)->info == block);
 380
 381                 /* count number of free slots */
 382                 for (i = 0; i < count; ++i) {
 383                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 384                         if (!MS_OBJ_ALLOCED (obj, block))
 385                                 ++num_free;
 386                 }
 387
 388                 /* check free list */
 389                 for (free = block->free_list; free; free = (void**)*free) {
 390                         g_assert (MS_BLOCK_FOR_OBJ (free) == block);
 391                         --num_free;
 392                 }
 393                 g_assert (num_free == 0);
 394
 395                 /* check all mark words are zero */
 396                 if (block->swept) {
 397                         for (i = 0; i < MS_NUM_MARK_WORDS; ++i)
 398                                 g_assert (block->mark_words [i] == 0);
 399                 }
 400         } END_FOREACH_BLOCK;
 401
 402         /* check free blocks */
 403         for (i = 0; i < num_block_obj_sizes; ++i) {
 404                 int j;
 405                 for (j = 0; j < MS_BLOCK_TYPE_MAX; ++j)
 406                         check_block_free_list (free_block_lists [j][i], block_obj_sizes [i], j & MS_BLOCK_FLAG_PINNED);
 407         }
 408
 409         check_empty_blocks ();
 410 }
 411 #endif
 412
 413 static gboolean
 414 ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
 415 {
 416         int size = block_obj_sizes [size_index];
 417         int count = MS_BLOCK_FREE / size;
 418         MSBlockInfo *info;
 419         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 420         char *obj_start;
 421         int i;
 422
 423         if (!sgen_memgov_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
 424                 return FALSE;
 425
 426         info = (MSBlockInfo*)ms_get_empty_block ();
 427
 428         SGEN_ASSERT (9, count >= 2, "block with %d objects, it must hold at least 2", count);
 429
 430         info->obj_size = size;
 431         info->obj_size_index = size_index;
 432         info->pinned = pinned;
 433         info->has_references = has_references;
 434         info->has_pinned = pinned;
 435         /*
 436          * Blocks that are to-space are not evacuated from.  During an major collection
 437          * blocks are allocated for two reasons: evacuating objects from the nursery and
 438          * evacuating them from major blocks marked for evacuation.  In both cases we don't
 439          * want further evacuation.
 440          */
 441         info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD);
 442         info->swept = 1;
 443 #ifdef SGEN_HAVE_CONCURRENT_MARK
 444         info->cardtable_mod_union = NULL;
 445 #endif
 446
 447         update_heap_boundaries_for_block (info);
 448
 449         /* build free list */
 450         obj_start = MS_BLOCK_FOR_BLOCK_INFO (info) + MS_BLOCK_SKIP;
 451         info->free_list = (void**)obj_start;
 452         /* we're skipping the last one - it must be nulled */
 453         for (i = 0; i < count - 1; ++i) {
 454                 char *next_obj_start = obj_start + size;
 455                 *(void**)obj_start = next_obj_start;
 456                 obj_start = next_obj_start;
 457         }
 458         /* the last one */
 459         *(void**)obj_start = NULL;
 460
 461         info->next_free = free_blocks [size_index];
 462         free_blocks [size_index] = info;
 463
 464         sgen_pointer_queue_add (&allocated_blocks, BLOCK_TAG (info));
 465
 466         ++num_major_sections;
 467         return TRUE;
 468 }
 469
 470 static gboolean
 471 obj_is_from_pinned_alloc (char *ptr)
 472 {
 473         MSBlockInfo *block;
 474
 475         FOREACH_BLOCK (block) {
 476                 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE)
 477                         return block->pinned;
 478         } END_FOREACH_BLOCK;
 479         return FALSE;
 480 }
 481
 482 static void*
 483 unlink_slot_from_free_list_uncontested (MSBlockInfo **free_blocks, int size_index)
 484 {
 485         MSBlockInfo *block;
 486         void *obj;
 487
 488         block = free_blocks [size_index];
 489         SGEN_ASSERT (9, block, "no free block to unlink from free_blocks %p size_index %d", free_blocks, size_index);
 490
 491         if (G_UNLIKELY (!block->swept)) {
 492                 stat_major_blocks_lazy_swept ++;
 493                 sweep_block (block, FALSE);
 494         }
 495
 496         obj = block->free_list;
 497         SGEN_ASSERT (9, obj, "block %p in free list had no available object to alloc from", block);
 498
 499         block->free_list = *(void**)obj;
 500         if (!block->free_list) {
 501                 free_blocks [size_index] = block->next_free;
 502                 block->next_free = NULL;
 503         }
 504
 505         return obj;
 506 }
 507
 508 static void*
 509 alloc_obj (MonoVTable *vtable, size_t size, gboolean pinned, gboolean has_references)
 510 {
 511         int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 512         MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
 513         void *obj;
 514
 515         if (!free_blocks [size_index]) {
 516                 if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references)))
 517                         return NULL;
 518         }
 519
 520         obj = unlink_slot_from_free_list_uncontested (free_blocks, size_index);
 521
 522         *(MonoVTable**)obj = vtable;
 523
 524         return obj;
 525 }
 526
 527 static void*
 528 major_alloc_object (MonoVTable *vtable, size_t size, gboolean has_references)
 529 {
 530         return alloc_obj (vtable, size, FALSE, has_references);
 531 }
 532
 533 /*
 534  * We're not freeing the block if it's empty.  We leave that work for
 535  * the next major collection.
 536  *
 537  * This is just called from the domain clearing code, which runs in a
 538  * single thread and has the GC lock, so we don't need an extra lock.
 539  */
 540 static void
 541 free_object (char *obj, size_t size, gboolean pinned)
 542 {
 543         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 544         int word, bit;
 545
 546         if (!block->swept)
 547                 sweep_block (block, FALSE);
 548         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);
 549         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p is already free", obj);
 550         MS_CALC_MARK_BIT (word, bit, obj);
 551         SGEN_ASSERT (9, !MS_MARK_BIT (block, word, bit), "object %p has mark bit set");
 552         if (!block->free_list) {
 553                 MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
 554                 int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
 555                 SGEN_ASSERT (9, !block->next_free, "block %p doesn't have a free-list of object but belongs to a free-list of blocks");
 556                 block->next_free = free_blocks [size_index];
 557                 free_blocks [size_index] = block;
 558         }
 559         memset (obj, 0, size);
 560         *(void**)obj = block->free_list;
 561         block->free_list = (void**)obj;
 562 }
 563
 564 static void
 565 major_free_non_pinned_object (char *obj, size_t size)
 566 {
 567         free_object (obj, size, FALSE);
 568 }
 569
 570 /* size is a multiple of SGEN_ALLOC_ALIGN */
 571 static void*
 572 major_alloc_small_pinned_obj (MonoVTable *vtable, size_t size, gboolean has_references)
 573 {
 574         void *res;
 575
 576         res = alloc_obj (vtable, size, TRUE, has_references);
 577          /*If we failed to alloc memory, we better try releasing memory
 578           *as pinned alloc is requested by the runtime.
 579           */
 580          if (!res) {
 581                 sgen_perform_collection (0, GENERATION_OLD, "pinned alloc failure", TRUE);
 582                 res = alloc_obj (vtable, size, TRUE, has_references);
 583          }
 584          return res;
 585 }
 586
 587 static void
 588 free_pinned_object (char *obj, size_t size)
 589 {
 590         free_object (obj, size, TRUE);
 591 }
 592
 593 /*
 594  * size is already rounded up and we hold the GC lock.
 595  */
 596 static void*
 597 major_alloc_degraded (MonoVTable *vtable, size_t size)
 598 {
 599         void *obj;
 600         size_t old_num_sections;
 601
 602         old_num_sections = num_major_sections;
 603
 604         obj = alloc_obj (vtable, size, FALSE, SGEN_VTABLE_HAS_REFERENCES (vtable));
 605         if (G_LIKELY (obj)) {
 606                 HEAVY_STAT (++stat_objects_alloced_degraded);
 607                 HEAVY_STAT (stat_bytes_alloced_degraded += size);
 608                 g_assert (num_major_sections >= old_num_sections);
 609                 sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
 610         }
 611         return obj;
 612 }
 613
 614 /*
 615  * obj is some object.  If it's not in the major heap (i.e. if it's in
 616  * the nursery or LOS), return FALSE.  Otherwise return whether it's
 617  * been marked or copied.
 618  */
 619 static gboolean
 620 major_is_object_live (char *obj)
 621 {
 622         MSBlockInfo *block;
 623         int word, bit;
 624         mword objsize;
 625
 626         if (sgen_ptr_in_nursery (obj))
 627                 return FALSE;
 628
 629         objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 630
 631         /* LOS */
 632         if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
 633                 return FALSE;
 634
 635         /* now we know it's in a major block */
 636         block = MS_BLOCK_FOR_OBJ (obj);
 637         SGEN_ASSERT (9, !block->pinned, "block %p is pinned, BTW why is this bad?");
 638         MS_CALC_MARK_BIT (word, bit, obj);
 639         return MS_MARK_BIT (block, word, bit) ? TRUE : FALSE;
 640 }
 641
 642 static gboolean
 643 major_ptr_is_in_non_pinned_space (char *ptr, char **start)
 644 {
 645         MSBlockInfo *block;
 646
 647         FOREACH_BLOCK (block) {
 648                 if (ptr >= MS_BLOCK_FOR_BLOCK_INFO (block) && ptr <= MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) {
 649                         int count = MS_BLOCK_FREE / block->obj_size;
 650                         int i;
 651
 652                         *start = NULL;
 653                         for (i = 0; i <= count; ++i) {
 654                                 if (ptr >= MS_BLOCK_OBJ (block, i) && ptr < MS_BLOCK_OBJ (block, i + 1)) {
 655                                         *start = MS_BLOCK_OBJ (block, i);
 656                                         break;
 657                                 }
 658                         }
 659                         return !block->pinned;
 660                 }
 661         } END_FOREACH_BLOCK;
 662         return FALSE;
 663 }
 664
 665 static void
 666 major_iterate_objects (IterateObjectsFlags flags, IterateObjectCallbackFunc callback, void *data)
 667 {
 668         gboolean sweep = flags & ITERATE_OBJECTS_SWEEP;
 669         gboolean non_pinned = flags & ITERATE_OBJECTS_NON_PINNED;
 670         gboolean pinned = flags & ITERATE_OBJECTS_PINNED;
 671         MSBlockInfo *block;
 672
 673         FOREACH_BLOCK (block) {
 674                 int count = MS_BLOCK_FREE / block->obj_size;
 675                 int i;
 676
 677                 if (block->pinned && !pinned)
 678                         continue;
 679                 if (!block->pinned && !non_pinned)
 680                         continue;
 681                 if (sweep && lazy_sweep) {
 682                         sweep_block (block, FALSE);
 683                         SGEN_ASSERT (0, block->swept, "Block must be swept after sweeping");
 684                 }
 685
 686                 for (i = 0; i < count; ++i) {
 687                         void **obj = (void**) MS_BLOCK_OBJ (block, i);
 688                         if (!block->swept) {
 689                                 int word, bit;
 690                                 MS_CALC_MARK_BIT (word, bit, obj);
 691                                 if (!MS_MARK_BIT (block, word, bit))
 692                                         continue;
 693                         }
 694                         if (MS_OBJ_ALLOCED (obj, block))
 695                                 callback ((char*)obj, block->obj_size, data);
 696                 }
 697         } END_FOREACH_BLOCK;
 698 }
 699
 700 static gboolean
 701 major_is_valid_object (char *object)
 702 {
 703         MSBlockInfo *block;
 704
 705         FOREACH_BLOCK (block) {
 706                 int idx;
 707                 char *obj;
 708
 709                 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > object) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= object))
 710                         continue;
 711
 712                 idx = MS_BLOCK_OBJ_INDEX (object, block);
 713                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 714                 if (obj != object)
 715                         return FALSE;
 716                 return MS_OBJ_ALLOCED (obj, block);
 717         } END_FOREACH_BLOCK;
 718
 719         return FALSE;
 720 }
 721
 722
 723 static MonoVTable*
 724 major_describe_pointer (char *ptr)
 725 {
 726         MSBlockInfo *block;
 727
 728         FOREACH_BLOCK (block) {
 729                 int idx;
 730                 char *obj;
 731                 gboolean live;
 732                 MonoVTable *vtable;
 733                 int w, b;
 734                 gboolean marked;
 735
 736                 if ((MS_BLOCK_FOR_BLOCK_INFO (block) > ptr) || ((MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE) <= ptr))
 737                         continue;
 738
 739                 SGEN_LOG (0, "major-ptr (block %p sz %d pin %d ref %d)\n",
 740                         MS_BLOCK_FOR_BLOCK_INFO (block), block->obj_size, block->pinned, block->has_references);
 741
 742                 idx = MS_BLOCK_OBJ_INDEX (ptr, block);
 743                 obj = (char*)MS_BLOCK_OBJ (block, idx);
 744                 live = MS_OBJ_ALLOCED (obj, block);
 745                 vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
 746
 747                 MS_CALC_MARK_BIT (w, b, obj);
 748                 marked = MS_MARK_BIT (block, w, b);
 749
 750                 if (obj == ptr) {
 751                         SGEN_LOG (0, "\t(");
 752                         if (live)
 753                                 SGEN_LOG (0, "object");
 754                         else
 755                                 SGEN_LOG (0, "dead-object");
 756                 } else {
 757                         if (live)
 758                                 SGEN_LOG (0, "interior-ptr offset %td", ptr - obj);
 759                         else
 760                                 SGEN_LOG (0, "dead-interior-ptr offset %td", ptr - obj);
 761                 }
 762
 763                 SGEN_LOG (0, " marked %d)\n", marked ? 1 : 0);
 764
 765                 return vtable;
 766         } END_FOREACH_BLOCK;
 767
 768         return NULL;
 769 }
 770
 771 static void
 772 major_check_scan_starts (void)
 773 {
 774 }
 775
 776 static void
 777 major_dump_heap (FILE *heap_dump_file)
 778 {
 779         MSBlockInfo *block;
 780         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
 781         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
 782         int i;
 783
 784         for (i = 0; i < num_block_obj_sizes; ++i)
 785                 slots_available [i] = slots_used [i] = 0;
 786
 787         FOREACH_BLOCK (block) {
 788                 int index = ms_find_block_obj_size_index (block->obj_size);
 789                 int count = MS_BLOCK_FREE / block->obj_size;
 790
 791                 slots_available [index] += count;
 792                 for (i = 0; i < count; ++i) {
 793                         if (MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block))
 794                                 ++slots_used [index];
 795                 }
 796         } END_FOREACH_BLOCK;
 797
 798         fprintf (heap_dump_file, "<occupancies>\n");
 799         for (i = 0; i < num_block_obj_sizes; ++i) {
 800                 fprintf (heap_dump_file, "<occupancy size=\"%d\" available=\"%d\" used=\"%d\" />\n",
 801                                 block_obj_sizes [i], slots_available [i], slots_used [i]);
 802         }
 803         fprintf (heap_dump_file, "</occupancies>\n");
 804
 805         FOREACH_BLOCK (block) {
 806                 int count = MS_BLOCK_FREE / block->obj_size;
 807                 int i;
 808                 int start = -1;
 809
 810                 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%zu\">\n", "old", (size_t)MS_BLOCK_FREE);
 811
 812                 for (i = 0; i <= count; ++i) {
 813                         if ((i < count) && MS_OBJ_ALLOCED (MS_BLOCK_OBJ (block, i), block)) {
 814                                 if (start < 0)
 815                                         start = i;
 816                         } else {
 817                                 if (start >= 0) {
 818                                         sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), MS_BLOCK_FOR_BLOCK_INFO (block));
 819                                         start = -1;
 820                                 }
 821                         }
 822                 }
 823
 824                 fprintf (heap_dump_file, "</section>\n");
 825         } END_FOREACH_BLOCK;
 826 }
 827
 828 #define LOAD_VTABLE     SGEN_LOAD_VTABLE
 829
 830 #define MS_MARK_OBJECT_AND_ENQUEUE_CHECKED(obj,desc,block,queue) do {   \
 831                 int __word, __bit;                                      \
 832                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 833                 if (!MS_MARK_BIT ((block), __word, __bit) && MS_OBJ_ALLOCED ((obj), (block))) { \
 834                         MS_SET_MARK_BIT ((block), __word, __bit);       \
 835                         if (sgen_gc_descr_has_references (desc))                        \
 836                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 837                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 838                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 839                 }                                                       \
 840         } while (0)
 841 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,desc,block,queue) do {           \
 842                 int __word, __bit;                                      \
 843                 MS_CALC_MARK_BIT (__word, __bit, (obj));                \
 844                 SGEN_ASSERT (9, MS_OBJ_ALLOCED ((obj), (block)), "object %p not allocated", obj); \
 845                 if (!MS_MARK_BIT ((block), __word, __bit)) {            \
 846                         MS_SET_MARK_BIT ((block), __word, __bit);       \
 847                         if (sgen_gc_descr_has_references (desc))                        \
 848                                 GRAY_OBJECT_ENQUEUE ((queue), (obj), (desc)); \
 849                         binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
 850                         INC_NUM_MAJOR_OBJECTS_MARKED ();                \
 851                 }                                                       \
 852         } while (0)
 853
 854 static void
 855 pin_major_object (char *obj, SgenGrayQueue *queue)
 856 {
 857         MSBlockInfo *block;
 858
 859 #ifdef SGEN_HAVE_CONCURRENT_MARK
 860         if (concurrent_mark)
 861                 g_assert_not_reached ();
 862 #endif
 863
 864         block = MS_BLOCK_FOR_OBJ (obj);
 865         block->has_pinned = TRUE;
 866         MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 867 }
 868
 869 #include "sgen-major-copy-object.h"
 870
 871 #ifdef SGEN_HAVE_CONCURRENT_MARK
 872 static void
 873 major_copy_or_mark_object_with_evacuation_concurrent (void **ptr, void *obj, SgenGrayQueue *queue)
 874 {
 875         SGEN_ASSERT (9, sgen_concurrent_collection_in_progress (), "Why are we scanning concurrently when there's no concurrent collection on?");
 876         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!");
 877
 878         g_assert (!SGEN_OBJECT_IS_FORWARDED (obj));
 879
 880         if (!sgen_ptr_in_nursery (obj)) {
 881                 mword objsize;
 882
 883                 objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 884
 885                 if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE) {
 886                         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
 887                         MS_MARK_OBJECT_AND_ENQUEUE (obj, sgen_obj_get_descriptor (obj), block, queue);
 888                 } else {
 889                         if (sgen_los_object_is_pinned (obj))
 890                                 return;
 891
 892 #ifdef ENABLE_DTRACE
 893                         if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
 894                                 MonoVTable *vt = (MonoVTable*)SGEN_LOAD_VTABLE (obj);
 895                                 MONO_GC_OBJ_PINNED ((mword)obj, sgen_safe_object_get_size (obj), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
 896                         }
 897 #endif
 898
 899                         sgen_los_pin_object (obj);
 900                         if (SGEN_OBJECT_HAS_REFERENCES (obj))
 901                                 GRAY_OBJECT_ENQUEUE (queue, obj, sgen_obj_get_descriptor (obj));
 902                         INC_NUM_MAJOR_OBJECTS_MARKED ();
 903                 }
 904         }
 905 }
 906 #endif
 907
 908 static long long
 909 major_get_and_reset_num_major_objects_marked (void)
 910 {
 911 #ifdef SGEN_COUNT_NUMBER_OF_MAJOR_OBJECTS_MARKED
 912         long long num = num_major_objects_marked;
 913         num_major_objects_marked = 0;
 914         return num;
 915 #else
 916         return 0;
 917 #endif
 918 }
 919
 920 #ifdef HEAVY_STATISTICS
 921 static guint64 stat_optimized_copy;
 922 static guint64 stat_optimized_copy_nursery;
 923 static guint64 stat_optimized_copy_nursery_forwarded;
 924 static guint64 stat_optimized_copy_nursery_pinned;
 925 static guint64 stat_optimized_copy_major;
 926 static guint64 stat_optimized_copy_major_small_fast;
 927 static guint64 stat_optimized_copy_major_small_slow;
 928 static guint64 stat_optimized_copy_major_large;
 929 static guint64 stat_optimized_copy_major_forwarded;
 930 static guint64 stat_optimized_copy_major_small_evacuate;
 931 static guint64 stat_optimized_major_scan;
 932 static guint64 stat_optimized_major_scan_no_refs;
 933
 934 static guint64 stat_drain_prefetch_fills;
 935 static guint64 stat_drain_prefetch_fill_failures;
 936 static guint64 stat_drain_loops;
 937 #endif
 938
 939 static void major_scan_object_with_evacuation (char *start, mword desc, SgenGrayQueue *queue);
 940
 941 #define COPY_OR_MARK_FUNCTION_NAME      major_copy_or_mark_object_no_evacuation
 942 #define SCAN_OBJECT_FUNCTION_NAME       major_scan_object_no_evacuation
 943 #define DRAIN_GRAY_STACK_FUNCTION_NAME  drain_gray_stack_no_evacuation
 944 #include "sgen-marksweep-drain-gray-stack.h"
 945
 946 #define COPY_OR_MARK_WITH_EVACUATION
 947 #define COPY_OR_MARK_FUNCTION_NAME      major_copy_or_mark_object_with_evacuation
 948 #define SCAN_OBJECT_FUNCTION_NAME       major_scan_object_with_evacuation
 949 #define DRAIN_GRAY_STACK_FUNCTION_NAME  drain_gray_stack_with_evacuation
 950 #include "sgen-marksweep-drain-gray-stack.h"
 951
 952 static gboolean
 953 drain_gray_stack (ScanCopyContext ctx)
 954 {
 955         gboolean evacuation = FALSE;
 956         int i;
 957         for (i = 0; i < num_block_obj_sizes; ++i) {
 958                 if (evacuate_block_obj_sizes [i]) {
 959                         evacuation = TRUE;
 960                         break;
 961                 }
 962         }
 963
 964         if (evacuation)
 965                 return drain_gray_stack_with_evacuation (ctx);
 966         else
 967                 return drain_gray_stack_no_evacuation (ctx);
 968 }
 969
 970 #ifdef SGEN_HAVE_CONCURRENT_MARK
 971 #include "sgen-marksweep-scan-object-concurrent.h"
 972 #endif
 973
 974 static void
 975 major_copy_or_mark_object_canonical (void **ptr, SgenGrayQueue *queue)
 976 {
 977         major_copy_or_mark_object_with_evacuation (ptr, *ptr, queue);
 978 }
 979
 980 #ifdef SGEN_HAVE_CONCURRENT_MARK
 981 static void
 982 major_copy_or_mark_object_concurrent_canonical (void **ptr, SgenGrayQueue *queue)
 983 {
 984         major_copy_or_mark_object_with_evacuation_concurrent (ptr, *ptr, queue);
 985 }
 986 #endif
 987
 988 static void
 989 mark_pinned_objects_in_block (MSBlockInfo *block, SgenGrayQueue *queue)
 990 {
 991         void **entry, **end;
 992         int last_index = -1;
 993
 994         if (block->pin_queue_first_entry == block->pin_queue_last_entry)
 995                 return;
 996
 997         block->has_pinned = TRUE;
 998
 999         entry = sgen_pinning_get_entry (block->pin_queue_first_entry);
1000         end = sgen_pinning_get_entry (block->pin_queue_last_entry);
1001
1002         for (; entry < end; ++entry) {
1003                 int index = MS_BLOCK_OBJ_INDEX (*entry, block);
1004                 char *obj;
1005                 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);
1006                 if (index == last_index)
1007                         continue;
1008                 obj = MS_BLOCK_OBJ (block, index);
1009                 MS_MARK_OBJECT_AND_ENQUEUE_CHECKED (obj, sgen_obj_get_descriptor (obj), block, queue);
1010                 last_index = index;
1011         }
1012 }
1013
1014 static inline void
1015 sweep_block_for_size (MSBlockInfo *block, int count, int obj_size)
1016 {
1017         int obj_index;
1018
1019         for (obj_index = 0; obj_index < count; ++obj_index) {
1020                 int word, bit;
1021                 void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, obj_index, obj_size);
1022
1023                 MS_CALC_MARK_BIT (word, bit, obj);
1024                 if (MS_MARK_BIT (block, word, bit)) {
1025                         SGEN_ASSERT (9, MS_OBJ_ALLOCED (obj, block), "object %p not allocated", obj);
1026                 } else {
1027                         /* an unmarked object */
1028                         if (MS_OBJ_ALLOCED (obj, block)) {
1029                                 /*
1030                                  * FIXME: Merge consecutive
1031                                  * slots for lower reporting
1032                                  * overhead.  Maybe memset
1033                                  * will also benefit?
1034                                  */
1035                                 binary_protocol_empty (obj, obj_size);
1036                                 MONO_GC_MAJOR_SWEPT ((mword)obj, obj_size);
1037                                 memset (obj, 0, obj_size);
1038                         }
1039                         *(void**)obj = block->free_list;
1040                         block->free_list = obj;
1041                 }
1042         }
1043 }
1044
1045 /*
1046  * sweep_block:
1047  *
1048  *   Traverse BLOCK, freeing and zeroing unused objects.
1049  */
1050 static void
1051 sweep_block (MSBlockInfo *block, gboolean during_major_collection)
1052 {
1053         int count;
1054         void *reversed = NULL;
1055
1056         if (!during_major_collection)
1057                 g_assert (!sgen_concurrent_collection_in_progress ());
1058
1059         if (block->swept)
1060                 return;
1061
1062         count = MS_BLOCK_FREE / block->obj_size;
1063
1064         block->free_list = NULL;
1065
1066         /* Use inline instances specialized to constant sizes, this allows the compiler to replace the memset calls with inline code */
1067         // FIXME: Add more sizes
1068         switch (block->obj_size) {
1069         case 16:
1070                 sweep_block_for_size (block, count, 16);
1071                 break;
1072         default:
1073                 sweep_block_for_size (block, count, block->obj_size);
1074                 break;
1075         }
1076
1077         /* reset mark bits */
1078         memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
1079
1080         /* Reverse free list so that it's in address order */
1081         reversed = NULL;
1082         while (block->free_list) {
1083                 void *next = *(void**)block->free_list;
1084                 *(void**)block->free_list = reversed;
1085                 reversed = block->free_list;
1086                 block->free_list = next;
1087         }
1088         block->free_list = reversed;
1089
1090         block->swept = 1;
1091 }
1092
1093 static inline int
1094 bitcount (mword d)
1095 {
1096         int count = 0;
1097
1098 #ifdef __GNUC__
1099         if (sizeof (mword) == sizeof (unsigned long))
1100                 count += __builtin_popcountl (d);
1101         else
1102                 count += __builtin_popcount (d);
1103 #else
1104         while (d) {
1105                 count ++;
1106                 d &= (d - 1);
1107         }
1108 #endif
1109         return count;
1110 }
1111
1112 static void
1113 ms_sweep (void)
1114 {
1115         int i;
1116         MSBlockInfo *block;
1117
1118         /* statistics for evacuation */
1119         int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
1120         int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
1121         int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
1122
1123 #ifdef SGEN_HAVE_CONCURRENT_MARK
1124         mword total_evacuate_heap = 0;
1125         mword total_evacuate_saved = 0;
1126 #endif
1127
1128         for (i = 0; i < num_block_obj_sizes; ++i)
1129                 slots_available [i] = slots_used [i] = num_blocks [i] = 0;
1130
1131         /* clear all the free lists */
1132         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
1133                 MSBlockInfo **free_blocks = free_block_lists [i];
1134                 int j;
1135                 for (j = 0; j < num_block_obj_sizes; ++j)
1136                         free_blocks [j] = NULL;
1137         }
1138
1139         /* traverse all blocks, free and zero unmarked objects */
1140         FOREACH_BLOCK (block) {
1141                 int count;
1142                 gboolean have_live = FALSE;
1143                 gboolean has_pinned;
1144                 gboolean have_free = FALSE;
1145                 int obj_size_index;
1146                 int nused = 0;
1147
1148                 obj_size_index = block->obj_size_index;
1149
1150                 has_pinned = block->has_pinned;
1151                 block->has_pinned = block->pinned;
1152
1153                 block->is_to_space = FALSE;
1154                 block->swept = 0;
1155
1156                 count = MS_BLOCK_FREE / block->obj_size;
1157
1158 #ifdef SGEN_HAVE_CONCURRENT_MARK
1159                 if (block->cardtable_mod_union) {
1160                         sgen_free_internal_dynamic (block->cardtable_mod_union, CARDS_PER_BLOCK, INTERNAL_MEM_CARDTABLE_MOD_UNION);
1161                         block->cardtable_mod_union = NULL;
1162                 }
1163 #endif
1164
1165                 /* Count marked objects in the block */
1166                 for (i = 0; i < MS_NUM_MARK_WORDS; ++i) {
1167                         nused += bitcount (block->mark_words [i]);
1168                 }
1169                 if (nused) {
1170                         have_live = TRUE;
1171                 }
1172                 if (nused < count)
1173                         have_free = TRUE;
1174
1175                 if (!lazy_sweep)
1176                         sweep_block (block, TRUE);
1177
1178                 if (have_live) {
1179                         if (!has_pinned) {
1180                                 ++num_blocks [obj_size_index];
1181                                 slots_used [obj_size_index] += nused;
1182                                 slots_available [obj_size_index] += count;
1183                         }
1184
1185                         /*
1186                          * If there are free slots in the block, add
1187                          * the block to the corresponding free list.
1188                          */
1189                         if (have_free) {
1190                                 MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
1191                                 int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
1192                                 block->next_free = free_blocks [index];
1193                                 free_blocks [index] = block;
1194                         }
1195
1196                         update_heap_boundaries_for_block (block);
1197                 } else {
1198                         /*
1199                          * Blocks without live objects are removed from the
1200                          * block list and freed.
1201                          */
1202                         DELETE_BLOCK_IN_FOREACH ();
1203
1204                         binary_protocol_empty (MS_BLOCK_OBJ (block, 0), (char*)MS_BLOCK_OBJ (block, count) - (char*)MS_BLOCK_OBJ (block, 0));
1205                         ms_free_block (block);
1206
1207                         --num_major_sections;
1208                 }
1209         } END_FOREACH_BLOCK;
1210         sgen_pointer_queue_remove_nulls (&allocated_blocks);
1211
1212         for (i = 0; i < num_block_obj_sizes; ++i) {
1213                 float usage = (float)slots_used [i] / (float)slots_available [i];
1214                 if (num_blocks [i] > 5 && usage < evacuation_threshold) {
1215                         evacuate_block_obj_sizes [i] = TRUE;
1216                         /*
1217                         g_print ("slot size %d - %d of %d used\n",
1218                                         block_obj_sizes [i], slots_used [i], slots_available [i]);
1219                         */
1220                 } else {
1221                         evacuate_block_obj_sizes [i] = FALSE;
1222                 }
1223 #ifdef SGEN_HAVE_CONCURRENT_MARK
1224                 {
1225                         mword total_bytes = block_obj_sizes [i] * slots_available [i];
1226                         total_evacuate_heap += total_bytes;
1227                         if (evacuate_block_obj_sizes [i])
1228                                 total_evacuate_saved += total_bytes - block_obj_sizes [i] * slots_used [i];
1229                 }
1230 #endif
1231         }
1232
1233 #ifdef SGEN_HAVE_CONCURRENT_MARK
1234         want_evacuation = (float)total_evacuate_saved / (float)total_evacuate_heap > (1 - concurrent_evacuation_threshold);
1235 #endif
1236
1237         have_swept = TRUE;
1238 }
1239
1240 static void
1241 major_sweep (void)
1242 {
1243         ms_sweep ();
1244 }
1245
1246 static int count_pinned_ref;
1247 static int count_pinned_nonref;
1248 static int count_nonpinned_ref;
1249 static int count_nonpinned_nonref;
1250
1251 static void
1252 count_nonpinned_callback (char *obj, size_t size, void *data)
1253 {
1254         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1255
1256         if (vtable->klass->has_references)
1257                 ++count_nonpinned_ref;
1258         else
1259                 ++count_nonpinned_nonref;
1260 }
1261
1262 static void
1263 count_pinned_callback (char *obj, size_t size, void *data)
1264 {
1265         MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
1266
1267         if (vtable->klass->has_references)
1268                 ++count_pinned_ref;
1269         else
1270                 ++count_pinned_nonref;
1271 }
1272
1273 static G_GNUC_UNUSED void
1274 count_ref_nonref_objs (void)
1275 {
1276         int total;
1277
1278         count_pinned_ref = 0;
1279         count_pinned_nonref = 0;
1280         count_nonpinned_ref = 0;
1281         count_nonpinned_nonref = 0;
1282
1283         major_iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, count_nonpinned_callback, NULL);
1284         major_iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, count_pinned_callback, NULL);
1285
1286         total = count_pinned_nonref + count_nonpinned_nonref + count_pinned_ref + count_nonpinned_ref;
1287
1288         g_print ("ref: %d pinned %d non-pinned   non-ref: %d pinned %d non-pinned  --  %.1f\n",
1289                         count_pinned_ref, count_nonpinned_ref,
1290                         count_pinned_nonref, count_nonpinned_nonref,
1291                         (count_pinned_nonref + count_nonpinned_nonref) * 100.0 / total);
1292 }
1293
1294 static int
1295 ms_calculate_block_obj_sizes (double factor, int *arr)
1296 {
1297         double target_size = sizeof (MonoObject);
1298         int num_sizes = 0;
1299         int last_size = 0;
1300
1301         do {
1302                 int target_count = (int)ceil (MS_BLOCK_FREE / target_size);
1303                 int size = MIN ((MS_BLOCK_FREE / target_count) & ~(SGEN_ALLOC_ALIGN - 1), SGEN_MAX_SMALL_OBJ_SIZE);
1304
1305                 if (size != last_size) {
1306                         if (arr)
1307                                 arr [num_sizes] = size;
1308                         ++num_sizes;
1309                         last_size = size;
1310                 }
1311
1312                 target_size *= factor;
1313         } while (last_size < SGEN_MAX_SMALL_OBJ_SIZE);
1314
1315         return num_sizes;
1316 }
1317
1318 /* only valid during minor collections */
1319 static mword old_num_major_sections;
1320
1321 static void
1322 major_start_nursery_collection (void)
1323 {
1324 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1325         consistency_check ();
1326 #endif
1327
1328         old_num_major_sections = num_major_sections;
1329 }
1330
1331 static void
1332 major_finish_nursery_collection (void)
1333 {
1334 #ifdef MARKSWEEP_CONSISTENCY_CHECK
1335         consistency_check ();
1336 #endif
1337         sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
1338 }
1339
1340 static void
1341 major_start_major_collection (void)
1342 {
1343         int i;
1344
1345         /* clear the free lists */
1346         for (i = 0; i < num_block_obj_sizes; ++i) {
1347                 if (!evacuate_block_obj_sizes [i])
1348                         continue;
1349
1350                 free_block_lists [0][i] = NULL;
1351                 free_block_lists [MS_BLOCK_FLAG_REFS][i] = NULL;
1352         }
1353
1354         // Sweep all unswept blocks
1355         if (lazy_sweep) {
1356                 MSBlockInfo *block;
1357
1358                 MONO_GC_SWEEP_BEGIN (GENERATION_OLD, TRUE);
1359
1360                 FOREACH_BLOCK (block) {
1361                         sweep_block (block, TRUE);
1362                 } END_FOREACH_BLOCK;
1363
1364                 MONO_GC_SWEEP_END (GENERATION_OLD, TRUE);
1365         }
1366 }
1367
1368 static void
1369 major_finish_major_collection (ScannedObjectCounts *counts)
1370 {
1371 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
1372         if (binary_protocol_is_enabled ()) {
1373                 counts->num_scanned_objects = scanned_objects_list.next_slot;
1374
1375                 sgen_pointer_queue_sort_uniq (&scanned_objects_list);
1376                 counts->num_unique_scanned_objects = scanned_objects_list.next_slot;
1377
1378                 sgen_pointer_queue_clear (&scanned_objects_list);
1379         }
1380 #endif
1381 }
1382
1383 #if SIZEOF_VOID_P != 8
1384 static int
1385 compare_pointers (const void *va, const void *vb) {
1386         char *a = *(char**)va, *b = *(char**)vb;
1387         if (a < b)
1388                 return -1;
1389         if (a > b)
1390                 return 1;
1391         return 0;
1392 }
1393 #endif
1394
1395 static void
1396 major_have_computer_minor_collection_allowance (void)
1397 {
1398         size_t section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
1399
1400         g_assert (have_swept);
1401
1402 #if SIZEOF_VOID_P != 8
1403         {
1404                 int i, num_empty_blocks_orig, num_blocks, arr_length;
1405                 void *block;
1406                 void **empty_block_arr;
1407                 void **rebuild_next;
1408
1409 #ifdef TARGET_WIN32
1410                 /*
1411                  * sgen_free_os_memory () asserts in mono_vfree () because windows doesn't like freeing the middle of
1412                  * a VirtualAlloc ()-ed block.
1413                  */
1414                 return;
1415 #endif
1416
1417                 if (num_empty_blocks <= section_reserve)
1418                         return;
1419                 SGEN_ASSERT (0, num_empty_blocks > 0, "section reserve can't be negative");
1420
1421                 num_empty_blocks_orig = num_empty_blocks;
1422                 empty_block_arr = (void**)sgen_alloc_internal_dynamic (sizeof (void*) * num_empty_blocks_orig,
1423                                 INTERNAL_MEM_MS_BLOCK_INFO_SORT, FALSE);
1424                 if (!empty_block_arr)
1425                         goto fallback;
1426
1427                 i = 0;
1428                 for (block = empty_blocks; block; block = *(void**)block)
1429                         empty_block_arr [i++] = block;
1430                 SGEN_ASSERT (0, i == num_empty_blocks, "empty block count wrong");
1431
1432                 sgen_qsort (empty_block_arr, num_empty_blocks, sizeof (void*), compare_pointers);
1433
1434                 /*
1435                  * We iterate over the free blocks, trying to find MS_BLOCK_ALLOC_NUM
1436                  * contiguous ones.  If we do, we free them.  If that's not enough to get to
1437                  * section_reserve, we halve the number of contiguous blocks we're looking
1438                  * for and have another go, until we're done with looking for pairs of
1439                  * blocks, at which point we give up and go to the fallback.
1440                  */
1441                 arr_length = num_empty_blocks_orig;
1442                 num_blocks = MS_BLOCK_ALLOC_NUM;
1443                 while (num_empty_blocks > section_reserve && num_blocks > 1) {
1444                         int first = -1;
1445                         int dest = 0;
1446
1447                         dest = 0;
1448                         for (i = 0; i < arr_length; ++i) {
1449                                 int d = dest;
1450                                 void *block = empty_block_arr [i];
1451                                 SGEN_ASSERT (0, block, "we're not shifting correctly");
1452                                 if (i != dest) {
1453                                         empty_block_arr [dest] = block;
1454                                         /*
1455                                          * This is not strictly necessary, but we're
1456                                          * cautious.
1457                                          */
1458                                         empty_block_arr [i] = NULL;
1459                                 }
1460                                 ++dest;
1461
1462                                 if (first < 0) {
1463                                         first = d;
1464                                         continue;
1465                                 }
1466
1467                                 SGEN_ASSERT (0, first >= 0 && d > first, "algorithm is wrong");
1468
1469                                 if ((char*)block != ((char*)empty_block_arr [d-1]) + MS_BLOCK_SIZE) {
1470                                         first = d;
1471                                         continue;
1472                                 }
1473
1474                                 if (d + 1 - first == num_blocks) {
1475                                         /*
1476                                          * We found num_blocks contiguous blocks.  Free them
1477                                          * and null their array entries.  As an optimization
1478                                          * we could, instead of nulling the entries, shift
1479                                          * the following entries over to the left, while
1480                                          * we're iterating.
1481                                          */
1482                                         int j;
1483                                         sgen_free_os_memory (empty_block_arr [first], MS_BLOCK_SIZE * num_blocks, SGEN_ALLOC_HEAP);
1484                                         for (j = first; j <= d; ++j)
1485                                                 empty_block_arr [j] = NULL;
1486                                         dest = first;
1487                                         first = -1;
1488
1489                                         num_empty_blocks -= num_blocks;
1490
1491                                         stat_major_blocks_freed += num_blocks;
1492                                         if (num_blocks == MS_BLOCK_ALLOC_NUM)
1493                                                 stat_major_blocks_freed_ideal += num_blocks;
1494                                         else
1495                                                 stat_major_blocks_freed_less_ideal += num_blocks;
1496
1497                                 }
1498                         }
1499
1500                         SGEN_ASSERT (0, dest <= i && dest <= arr_length, "array length is off");
1501                         arr_length = dest;
1502                         SGEN_ASSERT (0, arr_length == num_empty_blocks, "array length is off");
1503
1504                         num_blocks >>= 1;
1505                 }
1506
1507                 /* rebuild empty_blocks free list */
1508                 rebuild_next = (void**)&empty_blocks;
1509                 for (i = 0; i < arr_length; ++i) {
1510                         void *block = empty_block_arr [i];
1511                         SGEN_ASSERT (0, block, "we're missing blocks");
1512                         *rebuild_next = block;
1513                         rebuild_next = (void**)block;
1514                 }
1515                 *rebuild_next = NULL;
1516
1517                 /* free array */
1518                 sgen_free_internal_dynamic (empty_block_arr, sizeof (void*) * num_empty_blocks_orig, INTERNAL_MEM_MS_BLOCK_INFO_SORT);
1519         }
1520
1521         SGEN_ASSERT (0, num_empty_blocks >= 0, "we freed more blocks than we had in the first place?");
1522
1523  fallback:
1524         /*
1525          * This is our threshold.  If there's not more empty than used blocks, we won't
1526          * release uncontiguous blocks, in fear of fragmenting the address space.
1527          */
1528         if (num_empty_blocks <= num_major_sections)
1529                 return;
1530 #endif
1531
1532         while (num_empty_blocks > section_reserve) {
1533                 void *next = *(void**)empty_blocks;
1534                 sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE, SGEN_ALLOC_HEAP);
1535                 empty_blocks = next;
1536                 /*
1537                  * Needs not be atomic because this is running
1538                  * single-threaded.
1539                  */
1540                 --num_empty_blocks;
1541
1542                 ++stat_major_blocks_freed;
1543 #if SIZEOF_VOID_P != 8
1544                 ++stat_major_blocks_freed_individual;
1545 #endif
1546         }
1547 }
1548
1549 static void
1550 major_find_pin_queue_start_ends (SgenGrayQueue *queue)
1551 {
1552         MSBlockInfo *block;
1553
1554         FOREACH_BLOCK (block) {
1555                 sgen_find_optimized_pin_queue_area (MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SKIP, MS_BLOCK_FOR_BLOCK_INFO (block) + MS_BLOCK_SIZE,
1556                                 &block->pin_queue_first_entry, &block->pin_queue_last_entry);
1557         } END_FOREACH_BLOCK;
1558 }
1559
1560 static void
1561 major_pin_objects (SgenGrayQueue *queue)
1562 {
1563         MSBlockInfo *block;
1564
1565         FOREACH_BLOCK (block) {
1566                 mark_pinned_objects_in_block (block, queue);
1567         } END_FOREACH_BLOCK;
1568 }
1569
1570 static void
1571 major_init_to_space (void)
1572 {
1573 }
1574
1575 static void
1576 major_report_pinned_memory_usage (void)
1577 {
1578         g_assert_not_reached ();
1579 }
1580
1581 static gint64
1582 major_get_used_size (void)
1583 {
1584         gint64 size = 0;
1585         MSBlockInfo *block;
1586
1587         FOREACH_BLOCK (block) {
1588                 int count = MS_BLOCK_FREE / block->obj_size;
1589                 void **iter;
1590                 size += count * block->obj_size;
1591                 for (iter = block->free_list; iter; iter = (void**)*iter)
1592                         size -= block->obj_size;
1593         } END_FOREACH_BLOCK;
1594
1595         return size;
1596 }
1597
1598 static size_t
1599 get_num_major_sections (void)
1600 {
1601         return num_major_sections;
1602 }
1603
1604 static gboolean
1605 major_handle_gc_param (const char *opt)
1606 {
1607         if (g_str_has_prefix (opt, "evacuation-threshold=")) {
1608                 const char *arg = strchr (opt, '=') + 1;
1609                 int percentage = atoi (arg);
1610                 if (percentage < 0 || percentage > 100) {
1611                         fprintf (stderr, "evacuation-threshold must be an integer in the range 0-100.\n");
1612                         exit (1);
1613                 }
1614                 evacuation_threshold = (float)percentage / 100.0f;
1615                 return TRUE;
1616         } else if (!strcmp (opt, "lazy-sweep")) {
1617                 lazy_sweep = TRUE;
1618                 return TRUE;
1619         } else if (!strcmp (opt, "no-lazy-sweep")) {
1620                 lazy_sweep = FALSE;
1621                 return TRUE;
1622         }
1623
1624         return FALSE;
1625 }
1626
1627 static void
1628 major_print_gc_param_usage (void)
1629 {
1630         fprintf (stderr,
1631                         ""
1632                         "  evacuation-threshold=P (where P is a percentage, an integer in 0-100)\n"
1633                         "  (no-)lazy-sweep\n"
1634                         );
1635 }
1636
1637 static void
1638 major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
1639 {
1640         MSBlockInfo *block;
1641         gboolean has_references;
1642
1643         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
1644                 if (has_references)
1645                         callback ((mword)MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE);
1646         } END_FOREACH_BLOCK;
1647 }
1648
1649 #ifdef HEAVY_STATISTICS
1650 extern guint64 marked_cards;
1651 extern guint64 scanned_cards;
1652 extern guint64 scanned_objects;
1653 extern guint64 remarked_cards;
1654 #endif
1655
1656 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
1657 /*
1658  * MS blocks are 16K aligned.
1659  * Cardtables are 4K aligned, at least.
1660  * This means that the cardtable of a given block is 32 bytes aligned.
1661  */
1662 static guint8*
1663 initial_skip_card (guint8 *card_data)
1664 {
1665         mword *cards = (mword*)card_data;
1666         mword card;
1667         int i;
1668         for (i = 0; i < CARD_WORDS_PER_BLOCK; ++i) {
1669                 card = cards [i];
1670                 if (card)
1671                         break;
1672         }
1673
1674         if (i == CARD_WORDS_PER_BLOCK)
1675                 return card_data + CARDS_PER_BLOCK;
1676
1677 #if defined(__i386__) && defined(__GNUC__)
1678         return card_data + i * 4 +  (__builtin_ffs (card) - 1) / 8;
1679 #elif defined(__x86_64__) && defined(__GNUC__)
1680         return card_data + i * 8 +  (__builtin_ffsll (card) - 1) / 8;
1681 #elif defined(__s390x__) && defined(__GNUC__)
1682         return card_data + i * 8 +  (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1683 #else
1684         for (i = i * SIZEOF_VOID_P; i < CARDS_PER_BLOCK; ++i) {
1685                 if (card_data [i])
1686                         return &card_data [i];
1687         }
1688         return card_data;
1689 #endif
1690 }
1691
1692
1693 static G_GNUC_UNUSED guint8*
1694 skip_card (guint8 *card_data, guint8 *card_data_end)
1695 {
1696         while (card_data < card_data_end && !*card_data)
1697                 ++card_data;
1698         return card_data;
1699 }
1700
1701 #define MS_BLOCK_OBJ_INDEX_FAST(o,b,os) (((char*)(o) - ((b) + MS_BLOCK_SKIP)) / (os))
1702 #define MS_BLOCK_OBJ_FAST(b,os,i)                       ((b) + MS_BLOCK_SKIP + (os) * (i))
1703 #define MS_OBJ_ALLOCED_FAST(o,b)                (*(void**)(o) && (*(char**)(o) < (b) || *(char**)(o) >= (b) + MS_BLOCK_SIZE))
1704
1705 static void
1706 major_scan_card_table (gboolean mod_union, SgenGrayQueue *queue)
1707 {
1708         MSBlockInfo *block;
1709         gboolean has_references;
1710         ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
1711
1712 #ifdef SGEN_HAVE_CONCURRENT_MARK
1713         if (!concurrent_mark)
1714                 g_assert (!mod_union);
1715 #else
1716         g_assert (!mod_union);
1717 #endif
1718
1719         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
1720                 int block_obj_size;
1721                 char *block_start;
1722
1723                 if (!has_references)
1724                         continue;
1725
1726                 block_obj_size = block->obj_size;
1727                 block_start = MS_BLOCK_FOR_BLOCK_INFO (block);
1728
1729                 if (block_obj_size >= CARD_SIZE_IN_BYTES) {
1730                         guint8 *cards;
1731 #ifndef SGEN_HAVE_OVERLAPPING_CARDS
1732                         guint8 cards_data [CARDS_PER_BLOCK];
1733 #endif
1734                         char *obj, *end, *base;
1735
1736                         if (mod_union) {
1737 #ifdef SGEN_HAVE_CONCURRENT_MARK
1738                                 cards = block->cardtable_mod_union;
1739                                 /*
1740                                  * This happens when the nursery
1741                                  * collection that precedes finishing
1742                                  * the concurrent collection allocates
1743                                  * new major blocks.
1744                                  */
1745                                 if (!cards)
1746                                         continue;
1747 #endif
1748                         } else {
1749                         /*We can avoid the extra copy since the remark cardtable was cleaned before */
1750 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1751                                 cards = sgen_card_table_get_card_scan_address ((mword)block_start);
1752 #else
1753                                 cards = cards_data;
1754                                 if (!sgen_card_table_get_card_data (cards_data, (mword)block_start, CARDS_PER_BLOCK))
1755                                         continue;
1756 #endif
1757                         }
1758
1759                         obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, 0);
1760                         end = block_start + MS_BLOCK_SIZE;
1761                         base = sgen_card_table_align_pointer (obj);
1762
1763                         cards += MS_BLOCK_SKIP >> CARD_BITS;
1764
1765                         while (obj < end) {
1766                                 size_t card_offset;
1767
1768                                 if (!block->swept)
1769                                         sweep_block (block, FALSE);
1770
1771                                 if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
1772                                         goto next_large;
1773
1774                                 if (mod_union) {
1775                                         /* FIXME: do this more efficiently */
1776                                         int w, b;
1777                                         MS_CALC_MARK_BIT (w, b, obj);
1778                                         if (!MS_MARK_BIT (block, w, b))
1779                                                 goto next_large;
1780                                 }
1781
1782                                 card_offset = (obj - base) >> CARD_BITS;
1783                                 sgen_cardtable_scan_object (obj, block_obj_size, cards + card_offset, mod_union, queue);
1784
1785                         next_large:
1786                                 obj += block_obj_size;
1787                         }
1788                 } else {
1789                         guint8 *card_data, *card_base;
1790                         guint8 *card_data_end;
1791
1792                         /*
1793                          * This is safe in face of card aliasing for the following reason:
1794                          *
1795                          * Major blocks are 16k aligned, or 32 cards aligned.
1796                          * Cards aliasing happens in powers of two, so as long as major blocks are aligned to their
1797                          * sizes, they won't overflow the cardtable overlap modulus.
1798                          */
1799                         if (mod_union) {
1800 #ifdef SGEN_HAVE_CONCURRENT_MARK
1801                                 card_data = card_base = block->cardtable_mod_union;
1802                                 /*
1803                                  * This happens when the nursery
1804                                  * collection that precedes finishing
1805                                  * the concurrent collection allocates
1806                                  * new major blocks.
1807                                  */
1808                                 if (!card_data)
1809                                         continue;
1810 #else
1811                                 g_assert_not_reached ();
1812                                 card_data = NULL;
1813 #endif
1814                         } else {
1815                                 card_data = card_base = sgen_card_table_get_card_scan_address ((mword)block_start);
1816                         }
1817                         card_data_end = card_data + CARDS_PER_BLOCK;
1818
1819                         card_data += MS_BLOCK_SKIP >> CARD_BITS;
1820
1821                         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)) {
1822                                 size_t index;
1823                                 size_t idx = card_data - card_base;
1824                                 char *start = (char*)(block_start + idx * CARD_SIZE_IN_BYTES);
1825                                 char *end = start + CARD_SIZE_IN_BYTES;
1826                                 char *first_obj, *obj;
1827
1828                                 HEAVY_STAT (++scanned_cards);
1829
1830                                 if (!*card_data)
1831                                         continue;
1832
1833                                 if (!block->swept)
1834                                         sweep_block (block, FALSE);
1835
1836                                 HEAVY_STAT (++marked_cards);
1837
1838                                 sgen_card_table_prepare_card_for_scanning (card_data);
1839
1840                                 if (idx == 0)
1841                                         index = 0;
1842                                 else
1843                                         index = MS_BLOCK_OBJ_INDEX_FAST (start, block_start, block_obj_size);
1844
1845                                 obj = first_obj = (char*)MS_BLOCK_OBJ_FAST (block_start, block_obj_size, index);
1846                                 while (obj < end) {
1847                                         if (!MS_OBJ_ALLOCED_FAST (obj, block_start))
1848                                                 goto next_small;
1849
1850                                         if (mod_union) {
1851                                                 /* FIXME: do this more efficiently */
1852                                                 int w, b;
1853                                                 MS_CALC_MARK_BIT (w, b, obj);
1854                                                 if (!MS_MARK_BIT (block, w, b))
1855                                                         goto next_small;
1856                                         }
1857
1858                                         HEAVY_STAT (++scanned_objects);
1859                                         scan_func (obj, sgen_obj_get_descriptor (obj), queue);
1860                                 next_small:
1861                                         obj += block_obj_size;
1862                                 }
1863                                 HEAVY_STAT (if (*card_data) ++remarked_cards);
1864                                 binary_protocol_card_scan (first_obj, obj - first_obj);
1865                         }
1866                 }
1867         } END_FOREACH_BLOCK;
1868 }
1869
1870 static void
1871 major_count_cards (long long *num_total_cards, long long *num_marked_cards)
1872 {
1873         MSBlockInfo *block;
1874         gboolean has_references;
1875         long long total_cards = 0;
1876         long long marked_cards = 0;
1877
1878         FOREACH_BLOCK_HAS_REFERENCES (block, has_references) {
1879                 guint8 *cards = sgen_card_table_get_card_scan_address ((mword) MS_BLOCK_FOR_BLOCK_INFO (block));
1880                 int i;
1881
1882                 if (!has_references)
1883                         continue;
1884
1885                 total_cards += CARDS_PER_BLOCK;
1886                 for (i = 0; i < CARDS_PER_BLOCK; ++i) {
1887                         if (cards [i])
1888                                 ++marked_cards;
1889                 }
1890         } END_FOREACH_BLOCK;
1891
1892         *num_total_cards = total_cards;
1893         *num_marked_cards = marked_cards;
1894 }
1895
1896 #ifdef SGEN_HAVE_CONCURRENT_MARK
1897 static void
1898 update_cardtable_mod_union (void)
1899 {
1900         MSBlockInfo *block;
1901
1902         FOREACH_BLOCK (block) {
1903                 size_t num_cards;
1904
1905                 block->cardtable_mod_union = sgen_card_table_update_mod_union (block->cardtable_mod_union,
1906                                 MS_BLOCK_FOR_BLOCK_INFO (block), MS_BLOCK_SIZE, &num_cards);
1907
1908                 SGEN_ASSERT (0, num_cards == CARDS_PER_BLOCK, "Number of cards calculation is wrong");
1909         } END_FOREACH_BLOCK;
1910 }
1911
1912 static guint8*
1913 major_get_cardtable_mod_union_for_object (char *obj)
1914 {
1915         MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
1916         return &block->cardtable_mod_union [(obj - (char*)sgen_card_table_align_pointer (MS_BLOCK_FOR_BLOCK_INFO (block))) >> CARD_BITS];
1917 }
1918 #endif
1919
1920 static void
1921 alloc_free_block_lists (MSBlockInfo ***lists)
1922 {
1923         int i;
1924         for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
1925                 lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
1926 }
1927
1928 #undef pthread_create
1929
1930 static void
1931 post_param_init (SgenMajorCollector *collector)
1932 {
1933         collector->sweeps_lazily = lazy_sweep;
1934 }
1935
1936 #ifdef SGEN_HAVE_CONCURRENT_MARK
1937 static void
1938 sgen_marksweep_init_internal (SgenMajorCollector *collector, gboolean is_concurrent)
1939 #else // SGEN_HAVE_CONCURRENT_MARK
1940 #error unknown configuration
1941 #endif // SGEN_HAVE_CONCURRENT_MARK
1942 {
1943         int i;
1944
1945         sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
1946
1947         num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
1948         block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
1949         ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
1950
1951         evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
1952         for (i = 0; i < num_block_obj_sizes; ++i)
1953                 evacuate_block_obj_sizes [i] = FALSE;
1954
1955         /*
1956         {
1957                 int i;
1958                 g_print ("block object sizes:\n");
1959                 for (i = 0; i < num_block_obj_sizes; ++i)
1960                         g_print ("%d\n", block_obj_sizes [i]);
1961         }
1962         */
1963
1964         alloc_free_block_lists (free_block_lists);
1965
1966         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES; ++i)
1967                 fast_block_obj_size_indexes [i] = ms_find_block_obj_size_index (i * 8);
1968         for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
1969                 g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
1970
1971         mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_alloced);
1972         mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_freed);
1973         mono_counters_register ("# major blocks lazy swept", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_lazy_swept);
1974         mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_objects_evacuated);
1975 #if SIZEOF_VOID_P != 8
1976         mono_counters_register ("# major blocks freed ideally", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_freed_ideal);
1977         mono_counters_register ("# major blocks freed less ideally", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_freed_less_ideal);
1978         mono_counters_register ("# major blocks freed individually", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_freed_individual);
1979         mono_counters_register ("# major blocks allocated less ideally", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_major_blocks_alloced_less_ideal);
1980 #endif
1981
1982         collector->section_size = MAJOR_SECTION_SIZE;
1983
1984 #ifdef SGEN_HAVE_CONCURRENT_MARK
1985         concurrent_mark = is_concurrent;
1986         if (is_concurrent) {
1987                 collector->is_concurrent = TRUE;
1988                 collector->want_synchronous_collection = &want_evacuation;
1989         } else
1990 #endif
1991         {
1992                 collector->is_concurrent = FALSE;
1993                 collector->want_synchronous_collection = NULL;
1994         }
1995         collector->get_and_reset_num_major_objects_marked = major_get_and_reset_num_major_objects_marked;
1996         collector->supports_cardtable = TRUE;
1997
1998         collector->have_swept = &have_swept;
1999
2000         collector->alloc_heap = major_alloc_heap;
2001         collector->is_object_live = major_is_object_live;
2002         collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
2003         collector->alloc_degraded = major_alloc_degraded;
2004
2005         collector->alloc_object = major_alloc_object;
2006         collector->free_pinned_object = free_pinned_object;
2007         collector->iterate_objects = major_iterate_objects;
2008         collector->free_non_pinned_object = major_free_non_pinned_object;
2009         collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
2010         collector->pin_objects = major_pin_objects;
2011         collector->pin_major_object = pin_major_object;
2012         collector->scan_card_table = major_scan_card_table;
2013         collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
2014 #ifdef SGEN_HAVE_CONCURRENT_MARK
2015         if (is_concurrent) {
2016                 collector->update_cardtable_mod_union = update_cardtable_mod_union;
2017                 collector->get_cardtable_mod_union_for_object = major_get_cardtable_mod_union_for_object;
2018         }
2019 #endif
2020         collector->init_to_space = major_init_to_space;
2021         collector->sweep = major_sweep;
2022         collector->check_scan_starts = major_check_scan_starts;
2023         collector->dump_heap = major_dump_heap;
2024         collector->get_used_size = major_get_used_size;
2025         collector->start_nursery_collection = major_start_nursery_collection;
2026         collector->finish_nursery_collection = major_finish_nursery_collection;
2027         collector->start_major_collection = major_start_major_collection;
2028         collector->finish_major_collection = major_finish_major_collection;
2029         collector->have_computed_minor_collection_allowance = major_have_computer_minor_collection_allowance;
2030         collector->ptr_is_in_non_pinned_space = major_ptr_is_in_non_pinned_space;
2031         collector->obj_is_from_pinned_alloc = obj_is_from_pinned_alloc;
2032         collector->report_pinned_memory_usage = major_report_pinned_memory_usage;
2033         collector->get_num_major_sections = get_num_major_sections;
2034         collector->handle_gc_param = major_handle_gc_param;
2035         collector->print_gc_param_usage = major_print_gc_param_usage;
2036         collector->post_param_init = post_param_init;
2037         collector->is_valid_object = major_is_valid_object;
2038         collector->describe_pointer = major_describe_pointer;
2039         collector->count_cards = major_count_cards;
2040
2041         collector->major_ops.copy_or_mark_object = major_copy_or_mark_object_canonical;
2042         collector->major_ops.scan_object = major_scan_object_with_evacuation;
2043 #ifdef SGEN_HAVE_CONCURRENT_MARK
2044         if (is_concurrent) {
2045                 collector->major_concurrent_ops.copy_or_mark_object = major_copy_or_mark_object_concurrent_canonical;
2046                 collector->major_concurrent_ops.scan_object = major_scan_object_no_mark_concurrent;
2047                 collector->major_concurrent_ops.scan_vtype = major_scan_vtype_concurrent;
2048         }
2049 #endif
2050
2051 #if !defined (FIXED_HEAP) && !defined (SGEN_PARALLEL_MARK)
2052         /* FIXME: this will not work with evacuation or the split nursery. */
2053         if (!is_concurrent)
2054                 collector->drain_gray_stack = drain_gray_stack;
2055
2056 #ifdef HEAVY_STATISTICS
2057         mono_counters_register ("Optimized copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy);
2058         mono_counters_register ("Optimized copy nursery", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_nursery);
2059         mono_counters_register ("Optimized copy nursery forwarded", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_nursery_forwarded);
2060         mono_counters_register ("Optimized copy nursery pinned", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_nursery_pinned);
2061         mono_counters_register ("Optimized copy major", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_major);
2062         mono_counters_register ("Optimized copy major small fast", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_major_small_fast);
2063         mono_counters_register ("Optimized copy major small slow", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_major_small_slow);
2064         mono_counters_register ("Optimized copy major large", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_copy_major_large);
2065         mono_counters_register ("Optimized major scan", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_major_scan);
2066         mono_counters_register ("Optimized major scan no refs", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_optimized_major_scan_no_refs);
2067
2068         mono_counters_register ("Gray stack drain loops", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_drain_loops);
2069         mono_counters_register ("Gray stack prefetch fills", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_drain_prefetch_fills);
2070         mono_counters_register ("Gray stack prefetch failures", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_drain_prefetch_fill_failures);
2071 #endif
2072 #endif
2073
2074 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
2075         mono_mutex_init (&scanned_objects_list_lock);
2076 #endif
2077
2078         SGEN_ASSERT (0, SGEN_MAX_SMALL_OBJ_SIZE <= MS_BLOCK_FREE / 2, "MAX_SMALL_OBJ_SIZE must be at most MS_BLOCK_FREE / 2");
2079
2080         /*cardtable requires major pages to be 8 cards aligned*/
2081         g_assert ((MS_BLOCK_SIZE % (8 * CARD_SIZE_IN_BYTES)) == 0);
2082 }
2083
2084 #ifdef SGEN_HAVE_CONCURRENT_MARK
2085 void
2086 sgen_marksweep_init (SgenMajorCollector *collector)
2087 {
2088         sgen_marksweep_init_internal (collector, FALSE);
2089 }
2090
2091 void
2092 sgen_marksweep_conc_init (SgenMajorCollector *collector)
2093 {
2094         sgen_marksweep_init_internal (collector, TRUE);
2095 }
2096 #endif
2097
2098 #endif