[dtrace] Probe for pinning of objects.
[mono.git] / mono / metadata / sgen-marksweep.c
index d8634b9d306786ddfd4dfb68f22980fc7ca350f6..72cd5c5b4a3732615761733183e2e4c8c6620a8f 100644 (file)
@@ -42,6 +42,7 @@
 #include "metadata/sgen-gc.h"
 #include "metadata/sgen-protocol.h"
 #include "metadata/sgen-cardtable.h"
+#include "metadata/sgen-memory-governor.h"
 #include "metadata/gc-internal.h"
 
 #define MS_BLOCK_SIZE  (16*1024)
@@ -100,9 +101,9 @@ struct _MSBlockInfo {
 };
 
 #ifdef FIXED_HEAP
-static int ms_heap_num_blocks = MS_DEFAULT_HEAP_NUM_BLOCKS;
+static mword ms_heap_num_blocks = MS_DEFAULT_HEAP_NUM_BLOCKS;
 
-#define ms_heap_start  nursery_end
+static char *ms_heap_start;
 static char *ms_heap_end;
 
 #define MS_PTR_IN_SMALL_MAJOR_HEAP(p)  ((char*)(p) >= ms_heap_start && (char*)(p) < ms_heap_end)
@@ -176,23 +177,16 @@ static int fast_block_obj_size_indexes [MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES];
 
 #ifdef SGEN_PARALLEL_MARK
 static LOCK_DECLARE (ms_block_list_mutex);
-#define LOCK_MS_BLOCK_LIST pthread_mutex_lock (&ms_block_list_mutex)
-#define UNLOCK_MS_BLOCK_LIST pthread_mutex_unlock (&ms_block_list_mutex)
+#define LOCK_MS_BLOCK_LIST mono_mutex_lock (&ms_block_list_mutex)
+#define UNLOCK_MS_BLOCK_LIST mono_mutex_unlock (&ms_block_list_mutex)
 #endif
 
-/* we get this at init */
-static int nursery_bits;
-static char *nursery_start;
-static char *nursery_end;
-
 static gboolean *evacuate_block_obj_sizes;
 static float evacuation_threshold = 0.666;
 
 static gboolean concurrent_sweep = FALSE;
 static gboolean have_swept;
 
-#define ptr_in_nursery(p)      (SGEN_PTR_IN_NURSERY ((p), nursery_bits, nursery_start, nursery_end))
-
 /* all allocated blocks in the system */
 static MSBlockInfo *all_blocks;
 
@@ -216,7 +210,7 @@ static MSBlockInfo **free_block_lists [MS_BLOCK_TYPE_MAX];
 #ifdef HAVE_KW_THREAD
 static __thread MSBlockInfo ***workers_free_block_lists;
 #else
-static pthread_key_t workers_free_block_lists_key;
+static MonoNativeTlsKey workers_free_block_lists_key;
 #endif
 #endif
 
@@ -224,12 +218,9 @@ static long long stat_major_blocks_alloced = 0;
 static long long stat_major_blocks_freed = 0;
 static long long stat_major_objects_evacuated = 0;
 static long long stat_time_wait_for_sweep = 0;
-#ifdef SGEN_PARALLEL_MARK
-static long long stat_slots_allocated_in_vain = 0;
-#endif
 
 static gboolean ms_sweep_in_progress = FALSE;
-static pthread_t ms_sweep_thread;
+static MonoNativeThreadId ms_sweep_thread;
 static MonoSemType ms_sweep_cmd_semaphore;
 static MonoSemType ms_sweep_done_semaphore;
 
@@ -272,7 +263,7 @@ ms_wait_for_sweep_done (void)
                        g_error ("MONO_SEM_WAIT");
        }
        SGEN_TV_GETTIME (btv);
-       stat_time_wait_for_sweep += SGEN_TV_ELAPSED_MS (atv, btv);
+       stat_time_wait_for_sweep += SGEN_TV_ELAPSED (atv, btv);
 
        g_assert (ms_sweep_in_progress);
        ms_sweep_in_progress = FALSE;
@@ -286,7 +277,7 @@ ms_find_block_obj_size_index (int size)
        for (i = 0; i < num_block_obj_sizes; ++i)
                if (block_obj_sizes [i] >= size)
                        return i;
-       g_assert_not_reached ();
+       g_error ("no object of size %d\n", size);
 }
 
 #define FREE_BLOCKS_FROM(lists,p,r)    (lists [((p) ? MS_BLOCK_FLAG_PINNED : 0) | ((r) ? MS_BLOCK_FLAG_REFS : 0)])
@@ -295,7 +286,7 @@ ms_find_block_obj_size_index (int size)
 #ifdef HAVE_KW_THREAD
 #define FREE_BLOCKS_LOCAL(p,r)         (FREE_BLOCKS_FROM (workers_free_block_lists, (p), (r)))
 #else
-#define FREE_BLOCKS_LOCAL(p,r)         (FREE_BLOCKS_FROM (((MSBlockInfo***)(pthread_getspecific (workers_free_block_lists_key))), (p), (r)))
+#define FREE_BLOCKS_LOCAL(p,r)         (FREE_BLOCKS_FROM (((MSBlockInfo***)(mono_native_tls_get_value (workers_free_block_lists_key))), (p), (r)))
 #endif
 #else
 //#define FREE_BLOCKS_LOCAL(p,r)               (FREE_BLOCKS_FROM (free_block_lists, (p), (r)))
@@ -310,26 +301,24 @@ ms_find_block_obj_size_index (int size)
 static void*
 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 {
-       char *heap_start;
+       char *nursery_start;
        mword major_heap_size = ms_heap_num_blocks * MS_BLOCK_SIZE;
        mword alloc_size = nursery_size + major_heap_size;
-       int i;
+       mword i;
 
        g_assert (ms_heap_num_blocks > 0);
        g_assert (nursery_size % MS_BLOCK_SIZE == 0);
        if (nursery_align)
                g_assert (nursery_align % MS_BLOCK_SIZE == 0);
 
-       nursery_start = mono_sgen_alloc_os_memory_aligned (alloc_size, nursery_align ? nursery_align : MS_BLOCK_SIZE, TRUE);
-       nursery_end = heap_start = nursery_start + nursery_size;
-       nursery_bits = the_nursery_bits;
+       nursery_start = sgen_alloc_os_memory_aligned (alloc_size, nursery_align ? nursery_align : MS_BLOCK_SIZE, TRUE, TRUE, "heap");
+       ms_heap_start = nursery_start + nursery_size;
+       ms_heap_end = ms_heap_start + major_heap_size;
 
-       ms_heap_end = heap_start + major_heap_size;
-
-       block_infos = mono_sgen_alloc_internal_dynamic (sizeof (MSBlockInfo) * ms_heap_num_blocks, INTERNAL_MEM_MS_BLOCK_INFO);
+       block_infos = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo) * ms_heap_num_blocks, INTERNAL_MEM_MS_BLOCK_INFO, TRUE);
 
        for (i = 0; i < ms_heap_num_blocks; ++i) {
-               block_infos [i].block = heap_start + i * MS_BLOCK_SIZE;
+               block_infos [i].block = ms_heap_start + i * MS_BLOCK_SIZE;
                if (i < ms_heap_num_blocks - 1)
                        block_infos [i].next_free = &block_infos [i + 1];
                else
@@ -345,22 +334,20 @@ major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 static void*
 major_alloc_heap (mword nursery_size, mword nursery_align, int the_nursery_bits)
 {
+       char *start;
        if (nursery_align)
-               nursery_start = mono_sgen_alloc_os_memory_aligned (nursery_size, nursery_align, TRUE);
+               start = sgen_alloc_os_memory_aligned (nursery_size, nursery_align, TRUE, TRUE, "nursery");
        else
-               nursery_start = mono_sgen_alloc_os_memory (nursery_size, TRUE);
-
-       nursery_end = nursery_start + nursery_size;
-       nursery_bits = the_nursery_bits;
+               start = sgen_alloc_os_memory (nursery_size, TRUE, TRUE, "nursery");
 
-       return nursery_start;
+       return start;
 }
 #endif
 
 static void
 update_heap_boundaries_for_block (MSBlockInfo *block)
 {
-       mono_sgen_update_heap_boundaries ((mword)block->block, (mword)block->block + MS_BLOCK_SIZE);
+       sgen_update_heap_boundaries ((mword)block->block, (mword)block->block + MS_BLOCK_SIZE);
 }
 
 #ifdef FIXED_HEAP
@@ -373,7 +360,7 @@ ms_get_empty_block (void)
 
        do {
                block = empty_blocks;
-       } while (SGEN_CAS_PTR (&empty_blocks, block->next_free, block) != block);
+       } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block->next_free, block) != block);
 
        block->used = TRUE;
 
@@ -390,7 +377,7 @@ ms_free_block (MSBlockInfo *block)
        empty_blocks = block;
        block->used = FALSE;
        block->zeroed = FALSE;
-       mono_sgen_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
+       sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
 }
 #else
 static void*
@@ -402,7 +389,7 @@ ms_get_empty_block (void)
 
  retry:
        if (!empty_blocks) {
-               p = mono_sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * MS_BLOCK_ALLOC_NUM, MS_BLOCK_SIZE, TRUE);
+               p = sgen_alloc_os_memory_aligned (MS_BLOCK_SIZE * MS_BLOCK_ALLOC_NUM, MS_BLOCK_SIZE, TRUE, TRUE, "major heap section");
 
                for (i = 0; i < MS_BLOCK_ALLOC_NUM; ++i) {
                        block = p;
@@ -414,7 +401,7 @@ ms_get_empty_block (void)
                        do {
                                empty = empty_blocks;
                                *(void**)block = empty;
-                       } while (SGEN_CAS_PTR (&empty_blocks, block, empty) != empty);
+                       } while (SGEN_CAS_PTR ((gpointer*)&empty_blocks, block, empty) != empty);
                        p += MS_BLOCK_SIZE;
                }
 
@@ -445,7 +432,7 @@ ms_free_block (void *block)
 {
        void *empty;
 
-       mono_sgen_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
+       sgen_memgov_release_space (MS_BLOCK_SIZE, SPACE_MAJOR);
        memset (block, 0, MS_BLOCK_SIZE);
 
        do {
@@ -562,13 +549,13 @@ ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
        char *obj_start;
        int i;
 
-       if (!mono_sgen_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
+       if (!sgen_memgov_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
                return FALSE;
 
 #ifdef FIXED_HEAP
        info = ms_get_empty_block ();
 #else
-       info = mono_sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
+       info = sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
 #endif
 
        DEBUG (9, g_assert (count >= 2));
@@ -578,7 +565,7 @@ ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
        info->pinned = pinned;
        info->has_references = has_references;
        info->has_pinned = pinned;
-       info->is_to_space = (mono_sgen_get_current_collection_generation () == GENERATION_OLD);
+       info->is_to_space = (sgen_get_current_collection_generation () == GENERATION_OLD); /*FIXME WHY??? */
 #ifndef FIXED_HEAP
        info->block = ms_get_empty_block ();
 
@@ -725,6 +712,12 @@ alloc_obj_par (int size, gboolean pinned, gboolean has_references)
 
        return obj;
 }
+
+static void*
+major_par_alloc_object (int size, gboolean has_references)
+{
+       return alloc_obj_par (size, FALSE, has_references);
+}
 #endif
 
 static void*
@@ -809,8 +802,8 @@ major_alloc_small_pinned_obj (size_t size, gboolean has_references)
          *as pinned alloc is requested by the runtime.
          */
         if (!res) {
-                sgen_collect_major_no_lock ("pinned alloc failure");
-                res = alloc_obj (size, TRUE, has_references);
+               sgen_perform_collection (0, GENERATION_OLD, "pinned alloc failure");
+               res = alloc_obj (size, TRUE, has_references);
         }
         return res;
 }
@@ -840,7 +833,7 @@ major_alloc_degraded (MonoVTable *vtable, size_t size)
                HEAVY_STAT (++stat_objects_alloced_degraded);
                HEAVY_STAT (stat_bytes_alloced_degraded += size);
                g_assert (num_major_sections >= old_num_sections);
-               mono_sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
+               sgen_register_major_sections_alloced (num_major_sections - old_num_sections);
        }
        return obj;
 }
@@ -861,7 +854,7 @@ major_is_object_live (char *obj)
        mword objsize;
 #endif
 
-       if (ptr_in_nursery (obj))
+       if (sgen_ptr_in_nursery (obj))
                return FALSE;
 
 #ifdef FIXED_HEAP
@@ -869,7 +862,7 @@ major_is_object_live (char *obj)
        if (!MS_PTR_IN_SMALL_MAJOR_HEAP (obj))
                return FALSE;
 #else
-       objsize = SGEN_ALIGN_UP (mono_sgen_safe_object_get_size ((MonoObject*)obj));
+       objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 
        /* LOS */
        if (objsize > SGEN_MAX_SMALL_OBJ_SIZE)
@@ -919,6 +912,73 @@ major_iterate_objects (gboolean non_pinned, gboolean pinned, IterateObjectCallba
        } END_FOREACH_BLOCK;
 }
 
+static gboolean
+major_is_valid_object (char *object)
+{
+       MSBlockInfo *block;
+
+       ms_wait_for_sweep_done ();
+       FOREACH_BLOCK (block) {
+               int idx;
+               char *obj;
+
+               if ((block->block > object) || ((block->block + MS_BLOCK_SIZE) <= object))
+                       continue;
+
+               idx = MS_BLOCK_OBJ_INDEX (object, block);
+               obj = (char*)MS_BLOCK_OBJ (block, idx);
+               if (obj != object)
+                       return FALSE;
+               return MS_OBJ_ALLOCED (obj, block);
+       } END_FOREACH_BLOCK;
+
+       return FALSE;
+}
+
+
+static gboolean
+major_describe_pointer (char *ptr)
+{
+       MSBlockInfo *block;
+
+       FOREACH_BLOCK (block) {
+               int idx;
+               char *obj;
+               gboolean live;
+               MonoVTable *vtable;
+
+               if ((block->block > ptr) || ((block->block + MS_BLOCK_SIZE) <= ptr))
+                       continue;
+
+               fprintf (gc_debug_file, "major-ptr (block %p sz %d pin %d ref %d) ",
+                       block->block, block->obj_size, block->pinned, block->has_references);
+
+               idx = MS_BLOCK_OBJ_INDEX (ptr, block);
+               obj = (char*)MS_BLOCK_OBJ (block, idx);
+               live = MS_OBJ_ALLOCED (obj, block);
+               vtable = live ? (MonoVTable*)SGEN_LOAD_VTABLE (obj) : NULL;
+               
+               if (obj == ptr) {
+                       if (live)
+                               fprintf (gc_debug_file, "(object %s.%s)", vtable->klass->name_space, vtable->klass->name);
+                       else
+                               fprintf (gc_debug_file, "(dead-object)");
+               } else {
+                       if (live)
+                               fprintf (gc_debug_file, "(interior-ptr offset %td of %p %s.%s)",
+                                       ptr - obj,
+                                       obj, vtable->klass->name_space, vtable->klass->name);
+                       else
+                               fprintf (gc_debug_file, "(dead-interior-ptr to %td to %p)",
+                                       ptr - obj, obj);
+               }
+
+               return TRUE;
+       } END_FOREACH_BLOCK;
+
+       return FALSE;
+}
+
 static void
 major_check_scan_starts (void)
 {
@@ -966,7 +1026,7 @@ major_dump_heap (FILE *heap_dump_file)
                                        start = i;
                        } else {
                                if (start >= 0) {
-                                       mono_sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), block->block);
+                                       sgen_dump_occupied (MS_BLOCK_OBJ (block, start), MS_BLOCK_OBJ (block, i), block->block);
                                        start = -1;
                                }
                        }
@@ -985,7 +1045,7 @@ major_dump_heap (FILE *heap_dump_file)
                        MS_SET_MARK_BIT ((block), __word, __bit);       \
                        if ((block)->has_references)                    \
                                GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
-                       binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), mono_sgen_safe_object_get_size ((MonoObject*)(obj))); \
+                       binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
                }                                                       \
        } while (0)
 #define MS_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do {               \
@@ -996,7 +1056,7 @@ major_dump_heap (FILE *heap_dump_file)
                        MS_SET_MARK_BIT ((block), __word, __bit);       \
                        if ((block)->has_references)                    \
                                GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
-                       binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), mono_sgen_safe_object_get_size ((MonoObject*)(obj))); \
+                       binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
                }                                                       \
        } while (0)
 #define MS_PAR_MARK_OBJECT_AND_ENQUEUE(obj,block,queue) do {           \
@@ -1008,35 +1068,17 @@ major_dump_heap (FILE *heap_dump_file)
                if (!__was_marked) {                                    \
                        if ((block)->has_references)                    \
                                GRAY_OBJECT_ENQUEUE ((queue), (obj));   \
-                       binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), mono_sgen_safe_object_get_size ((MonoObject*)(obj))); \
+                       binary_protocol_mark ((obj), (gpointer)LOAD_VTABLE ((obj)), sgen_safe_object_get_size ((MonoObject*)(obj))); \
                }                                                       \
        } while (0)
 
-#ifdef SGEN_PARALLEL_MARK
 static void
-pin_or_update_par (void **ptr, void *obj, MonoVTable *vt, SgenGrayQueue *queue)
+pin_major_object (char *obj, SgenGrayQueue *queue)
 {
-       for (;;) {
-               mword vtable_word;
-
-               if (SGEN_CAS_PTR (obj, (void*)((mword)vt | SGEN_PINNED_BIT), vt) == vt) {
-                       mono_sgen_pin_object (obj, queue);
-                       break;
-               }
-
-               vtable_word = *(mword*)obj;
-               /*someone else forwarded it, update the pointer and bail out*/
-               if (vtable_word & SGEN_FORWARDED_BIT) {
-                       *ptr = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
-                       break;
-               }
-
-               /*someone pinned it, nothing to do.*/
-               if (vtable_word & SGEN_PINNED_BIT)
-                       break;
-       }
+       MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
+       block->has_pinned = TRUE;
+       MS_MARK_OBJECT_AND_ENQUEUE (obj, block, queue);
 }
-#endif
 
 #include "sgen-major-copy-object.h"
 
@@ -1054,7 +1096,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
        DEBUG (9, g_assert (obj));
        DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
 
-       if (ptr_in_nursery (obj)) {
+       if (sgen_ptr_in_nursery (obj)) {
                int word, bit;
                gboolean has_references;
                void *destination;
@@ -1069,22 +1111,27 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                if (vtable_word & SGEN_PINNED_BIT)
                        return;
 
+               /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
+               if (sgen_nursery_is_to_space (obj))
+                       return;
+
                HEAVY_STAT (++stat_objects_copied_major);
 
        do_copy_object:
-               objsize = SGEN_ALIGN_UP (mono_sgen_par_object_get_size (vt, (MonoObject*)obj));
+               objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
                has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
 
-               destination = alloc_obj_par (objsize, FALSE, has_references);
+               destination = sgen_minor_collector.par_alloc_for_promotion (obj, objsize, has_references);
                if (G_UNLIKELY (!destination)) {
-                       if (!ptr_in_nursery (obj)) {
+                       if (!sgen_ptr_in_nursery (obj)) {
                                int size_index;
                                block = MS_BLOCK_FOR_OBJ (obj);
                                size_index = block->obj_size_index;
                                evacuate_block_obj_sizes [size_index] = FALSE;
                        }
 
-                       pin_or_update_par (ptr, obj, vt, queue);
+                       sgen_parallel_pin_or_update (ptr, obj, vt, queue);
+                       sgen_set_pinned_from_failed_allocation (objsize);
                        return;
                }
 
@@ -1107,11 +1154,21 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                         * FIXME: If we make major_alloc_object() give
                         * us the block info, too, we won't have to
                         * re-fetch it here.
+                        *
+                        * FIXME (2): We should rework this to avoid all those nursery checks.
                         */
-                       block = MS_BLOCK_FOR_OBJ (obj);
-                       MS_CALC_MARK_BIT (word, bit, obj);
-                       DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
-                       MS_PAR_SET_MARK_BIT (was_marked, block, word, bit);
+                       /*
+                        * For the split nursery allocator the object
+                        * might still be in the nursery despite
+                        * having being promoted, in which case we
+                        * can't mark it.
+                        */
+                       if (!sgen_ptr_in_nursery (obj)) {
+                               block = MS_BLOCK_FOR_OBJ (obj);
+                               MS_CALC_MARK_BIT (word, bit, obj);
+                               DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
+                               MS_PAR_SET_MARK_BIT (was_marked, block, word, bit);
+                       }
                } else {
                        /*
                         * FIXME: We have allocated destination, but
@@ -1127,7 +1184,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
 
                        *ptr = obj;
 
-                       ++stat_slots_allocated_in_vain;
+                       HEAVY_STAT (++stat_slots_allocated_in_vain);
                }
        } else {
 #ifdef FIXED_HEAP
@@ -1141,7 +1198,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                        *ptr = (void*)vt;
                        return;
                }
-               objsize = SGEN_ALIGN_UP (mono_sgen_par_object_get_size (vt, (MonoObject*)obj));
+               objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
 
                if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
 #endif
@@ -1180,7 +1237,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
 
                        if (vtable_word & SGEN_PINNED_BIT)
                                return;
-                       binary_protocol_pin (obj, vt, mono_sgen_safe_object_get_size ((MonoObject*)obj));
+                       binary_protocol_pin (obj, vt, sgen_safe_object_get_size ((MonoObject*)obj));
                        if (SGEN_CAS_PTR (obj, (void*)(vtable_word | SGEN_PINNED_BIT), (void*)vtable_word) == (void*)vtable_word) {
                                if (SGEN_VTABLE_HAS_REFERENCES (vt))
                                        GRAY_OBJECT_ENQUEUE (queue, obj);
@@ -1202,7 +1259,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
        DEBUG (9, g_assert (obj));
        DEBUG (9, g_assert (current_collection_generation == GENERATION_OLD));
 
-       if (ptr_in_nursery (obj)) {
+       if (sgen_ptr_in_nursery (obj)) {
                int word, bit;
                char *forwarded, *old_obj;
 
@@ -1213,6 +1270,10 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                if (SGEN_OBJECT_IS_PINNED (obj))
                        return;
 
+               /* An object in the nursery To Space has already been copied and grayed. Nothing to do. */
+               if (sgen_nursery_is_to_space (obj))
+                       return;
+
                HEAVY_STAT (++stat_objects_copied_major);
 
        do_copy_object:
@@ -1220,7 +1281,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                obj = copy_object_no_checks (obj, queue);
                if (G_UNLIKELY (old_obj == obj)) {
                        /*If we fail to evacuate an object we just stop doing it for a given block size as all other will surely fail too.*/
-                       if (!ptr_in_nursery (obj)) {
+                       if (!sgen_ptr_in_nursery (obj)) {
                                int size_index;
                                block = MS_BLOCK_FOR_OBJ (obj);
                                size_index = block->obj_size_index;
@@ -1236,11 +1297,20 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                 * we have that, we can let the allocation function
                 * give us the block info, too, and we won't have to
                 * re-fetch it.
+                *
+                * FIXME (2): We should rework this to avoid all those nursery checks.
+                */
+               /*
+                * For the split nursery allocator the object might
+                * still be in the nursery despite having being
+                * promoted, in which case we can't mark it.
                 */
-               block = MS_BLOCK_FOR_OBJ (obj);
-               MS_CALC_MARK_BIT (word, bit, obj);
-               DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
-               MS_SET_MARK_BIT (block, word, bit);
+               if (!sgen_ptr_in_nursery (obj)) {
+                       block = MS_BLOCK_FOR_OBJ (obj);
+                       MS_CALC_MARK_BIT (word, bit, obj);
+                       DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
+                       MS_SET_MARK_BIT (block, word, bit);
+               }
        } else {
                char *forwarded;
 #ifdef FIXED_HEAP
@@ -1261,7 +1331,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                        return;
                }
 
-               objsize = SGEN_ALIGN_UP (mono_sgen_safe_object_get_size ((MonoObject*)obj));
+               objsize = SGEN_ALIGN_UP (sgen_safe_object_get_size ((MonoObject*)obj));
 
                if (objsize <= SGEN_MAX_SMALL_OBJ_SIZE)
 #endif
@@ -1288,6 +1358,7 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
 #endif
 
                        if (evacuate && !block->has_pinned) {
+                               g_assert (!SGEN_OBJECT_IS_PINNED (obj));
                                if (block->is_to_space)
                                        return;
                                HEAVY_STAT (++stat_major_objects_evacuated);
@@ -1298,7 +1369,10 @@ major_copy_or_mark_object (void **ptr, SgenGrayQueue *queue)
                } else {
                        if (SGEN_OBJECT_IS_PINNED (obj))
                                return;
-                       binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), mono_sgen_safe_object_get_size ((MonoObject*)obj));
+                       binary_protocol_pin (obj, (gpointer)SGEN_LOAD_VTABLE (obj), sgen_safe_object_get_size ((MonoObject*)obj));
+                       if (MONO_GC_OBJ_PINNED_ENABLED ()) {
+                               MONO_GC_OBJ_PINNED (obj, sgen_safe_object_get_size (obj), NULL, GENERATION_OLD);
+                       }
                        SGEN_PIN_OBJECT (obj);
                        /* FIXME: only enqueue if object has references */
                        GRAY_OBJECT_ENQUEUE (queue, obj);
@@ -1385,7 +1459,14 @@ ms_sweep (void)
                        } else {
                                /* an unmarked object */
                                if (MS_OBJ_ALLOCED (obj, block)) {
+                                       /*
+                                        * FIXME: Merge consecutive
+                                        * slots for lower reporting
+                                        * overhead.  Maybe memset
+                                        * will also benefit?
+                                        */
                                        binary_protocol_empty (obj, block->obj_size);
+                                       MONO_GC_MAJOR_SWEEPED (obj, block->obj_size);
                                        memset (obj, 0, block->obj_size);
                                }
                                *(void**)obj = block->free_list;
@@ -1433,7 +1514,7 @@ ms_sweep (void)
 #else
                        ms_free_block (block->block);
 
-                       mono_sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
+                       sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
 #endif
 
                        --num_major_sections;
@@ -1456,7 +1537,7 @@ ms_sweep (void)
        have_swept = TRUE;
 }
 
-static void*
+static mono_native_thread_return_t
 ms_sweep_thread_func (void *dummy)
 {
        g_assert (concurrent_sweep);
@@ -1466,7 +1547,7 @@ ms_sweep_thread_func (void *dummy)
 
                while ((result = MONO_SEM_WAIT (&ms_sweep_cmd_semaphore)) != 0) {
                        if (errno != EINTR)
-                               g_error ("MONO_SEM_WAIT");
+                               g_error ("MONO_SEM_WAIT FAILED with %d errno %d (%s)", result, errno, strerror (errno));
                }
 
                ms_sweep ();
@@ -1581,7 +1662,7 @@ major_finish_nursery_collection (void)
 #ifdef MARKSWEEP_CONSISTENCY_CHECK
        consistency_check ();
 #endif
-       mono_sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
+       sgen_register_major_sections_alloced (num_major_sections - old_num_major_sections);
 }
 
 static void
@@ -1610,7 +1691,7 @@ static void
 major_have_computer_minor_collection_allowance (void)
 {
 #ifndef FIXED_HEAP
-       int section_reserve = mono_sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
+       int section_reserve = sgen_get_minor_collection_allowance () / MS_BLOCK_SIZE;
 
        g_assert (have_swept);
        ms_wait_for_sweep_done ();
@@ -1626,7 +1707,7 @@ major_have_computer_minor_collection_allowance (void)
 
        while (num_empty_blocks > section_reserve) {
                void *next = *(void**)empty_blocks;
-               mono_sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE);
+               sgen_free_os_memory (empty_blocks, MS_BLOCK_SIZE, TRUE);
                empty_blocks = next;
                /*
                 * Needs not be atomic because this is running
@@ -1645,7 +1726,7 @@ major_find_pin_queue_start_ends (SgenGrayQueue *queue)
        MSBlockInfo *block;
 
        FOREACH_BLOCK (block) {
-               block->pin_queue_start = mono_sgen_find_optimized_pin_queue_area (block->block + MS_BLOCK_SKIP, block->block + MS_BLOCK_SIZE,
+               block->pin_queue_start = sgen_find_optimized_pin_queue_area (block->block + MS_BLOCK_SKIP, block->block + MS_BLOCK_SIZE,
                                &block->pin_queue_num_entries);
        } END_FOREACH_BLOCK;
 }
@@ -1757,7 +1838,7 @@ major_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
 extern long long marked_cards;
 extern long long scanned_cards;
 extern long long scanned_objects;
-
+extern long long remarked_cards;
 #endif
 
 #define CARD_WORDS_PER_BLOCK (CARDS_PER_BLOCK / SIZEOF_VOID_P)
@@ -1813,6 +1894,7 @@ static void
 major_scan_card_table (SgenGrayQueue *queue)
 {
        MSBlockInfo *block;
+       ScanObjectFunc scan_func = sgen_get_current_object_ops ()->scan_object;
 
        FOREACH_BLOCK (block) {
                int block_obj_size;
@@ -1852,7 +1934,6 @@ major_scan_card_table (SgenGrayQueue *queue)
                                obj += block_obj_size;
                        }
                } else {
-                       ScanObjectFunc scan_func = mono_sgen_get_minor_scan_object ();
                        guint8 *card_data, *card_base;
                        guint8 *card_data_end;
 
@@ -1895,6 +1976,7 @@ major_scan_card_table (SgenGrayQueue *queue)
                                        }
                                        obj += block_obj_size;
                                }
+                               HEAVY_STAT (if (*card_data) ++remarked_cards);
                        }
                }
        } END_FOREACH_BLOCK;
@@ -1902,7 +1984,7 @@ major_scan_card_table (SgenGrayQueue *queue)
 #endif
 
 static gboolean
-major_is_worker_thread (pthread_t thread)
+major_is_worker_thread (MonoNativeThreadId thread)
 {
        if (concurrent_sweep)
                return thread == ms_sweep_thread;
@@ -1915,7 +1997,7 @@ alloc_free_block_lists (MSBlockInfo ***lists)
 {
        int i;
        for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i)
-               lists [i] = mono_sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
+               lists [i] = sgen_alloc_internal_dynamic (sizeof (MSBlockInfo*) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
 }
 
 #ifdef SGEN_PARALLEL_MARK
@@ -1944,7 +2026,7 @@ major_init_worker_thread (void *data)
 #ifdef HAVE_KW_THREAD
        workers_free_block_lists = data;
 #else
-       pthread_setspecific (workers_free_block_lists_key, data);
+       mono_native_tls_set_value (workers_free_block_lists_key, data);
 #endif
 }
 
@@ -1967,7 +2049,7 @@ static void
 post_param_init (void)
 {
        if (concurrent_sweep) {
-               if (pthread_create (&ms_sweep_thread, NULL, ms_sweep_thread_func, NULL)) {
+               if (!mono_native_thread_create (&ms_sweep_thread, ms_sweep_thread_func, NULL)) {
                        fprintf (stderr, "Error: Could not create sweep thread.\n");
                        exit (1);
                }
@@ -1977,15 +2059,15 @@ post_param_init (void)
 void
 #ifdef SGEN_PARALLEL_MARK
 #ifdef FIXED_HEAP
-mono_sgen_marksweep_fixed_par_init
+sgen_marksweep_fixed_par_init
 #else
-mono_sgen_marksweep_par_init
+sgen_marksweep_par_init
 #endif
 #else
 #ifdef FIXED_HEAP
-mono_sgen_marksweep_fixed_init
+sgen_marksweep_fixed_init
 #else
-mono_sgen_marksweep_init
+sgen_marksweep_init
 #endif
 #endif
        (SgenMajorCollector *collector)
@@ -1993,14 +2075,14 @@ mono_sgen_marksweep_init
        int i;
 
 #ifndef FIXED_HEAP
-       mono_sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
+       sgen_register_fixed_internal_mem_type (INTERNAL_MEM_MS_BLOCK_INFO, sizeof (MSBlockInfo));
 #endif
 
        num_block_obj_sizes = ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, NULL);
-       block_obj_sizes = mono_sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
+       block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (int) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
        ms_calculate_block_obj_sizes (MS_BLOCK_OBJ_SIZE_FACTOR, block_obj_sizes);
 
-       evacuate_block_obj_sizes = mono_sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES);
+       evacuate_block_obj_sizes = sgen_alloc_internal_dynamic (sizeof (gboolean) * num_block_obj_sizes, INTERNAL_MEM_MS_TABLES, TRUE);
        for (i = 0; i < num_block_obj_sizes; ++i)
                evacuate_block_obj_sizes [i] = FALSE;
 
@@ -2020,17 +2102,17 @@ mono_sgen_marksweep_init
        for (i = 0; i < MS_NUM_FAST_BLOCK_OBJ_SIZE_INDEXES * 8; ++i)
                g_assert (MS_BLOCK_OBJ_SIZE_INDEX (i) == ms_find_block_obj_size_index (i));
 
+#ifdef SGEN_PARALLEL_MARK
        LOCK_INIT (ms_block_list_mutex);
+#endif
 
        mono_counters_register ("# major blocks allocated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_alloced);
        mono_counters_register ("# major blocks freed", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_blocks_freed);
        mono_counters_register ("# major objects evacuated", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_major_objects_evacuated);
-       mono_counters_register ("Wait for sweep time", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_time_wait_for_sweep);
+       mono_counters_register ("Wait for sweep time", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &stat_time_wait_for_sweep);
 #ifdef SGEN_PARALLEL_MARK
-       mono_counters_register ("Slots allocated in vain", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_slots_allocated_in_vain);
-
 #ifndef HAVE_KW_THREAD
-       pthread_key_create (&workers_free_block_lists_key, NULL);
+       mono_native_tls_alloc (&workers_free_block_lists_key, NULL);
 #endif
 #endif
 
@@ -2058,13 +2140,17 @@ mono_sgen_marksweep_init
        collector->is_object_live = major_is_object_live;
        collector->alloc_small_pinned_obj = major_alloc_small_pinned_obj;
        collector->alloc_degraded = major_alloc_degraded;
-       collector->copy_or_mark_object = major_copy_or_mark_object;
+
        collector->alloc_object = major_alloc_object;
+#ifdef SGEN_PARALLEL_MARK
+       collector->par_alloc_object = major_par_alloc_object;
+#endif
        collector->free_pinned_object = free_pinned_object;
        collector->iterate_objects = major_iterate_objects;
        collector->free_non_pinned_object = major_free_non_pinned_object;
        collector->find_pin_queue_start_ends = major_find_pin_queue_start_ends;
        collector->pin_objects = major_pin_objects;
+       collector->pin_major_object = pin_major_object;
 #ifdef SGEN_HAVE_CARDTABLE
        collector->scan_card_table = major_scan_card_table;
        collector->iterate_live_block_ranges = (void*)(void*) major_iterate_live_block_ranges;
@@ -2087,9 +2173,11 @@ mono_sgen_marksweep_init
        collector->print_gc_param_usage = major_print_gc_param_usage;
        collector->is_worker_thread = major_is_worker_thread;
        collector->post_param_init = post_param_init;
+       collector->is_valid_object = major_is_valid_object;
+       collector->describe_pointer = major_describe_pointer;
 
-       FILL_COLLECTOR_COPY_OBJECT (collector);
-       FILL_COLLECTOR_SCAN_OBJECT (collector);
+       collector->major_ops.copy_or_mark_object = major_copy_or_mark_object;
+       collector->major_ops.scan_object = major_scan_object;
 
 #ifdef SGEN_HAVE_CARDTABLE
        /*cardtable requires major pages to be 8 cards aligned*/