2 * sgen-nursery-allocator.c: Nursery allocation code.
4 * Copyright 2009-2010 Novell, Inc.
7 * Copyright 2011 Xamarin Inc (http://www.xamarin.com)
8 * Copyright (C) 2012 Xamarin Inc
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;
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.
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.
25 * The young generation is divided into fragments. This is because
26 * we can hand one fragments to a thread for lock-less fast alloc and
27 * because the young generation ends up fragmented anyway by pinned objects.
28 * Once a collection is done, a list of fragments is created. When doing
29 * thread local alloc we use smallish nurseries so we allow new threads to
30 * allocate memory from gen0 without triggering a collection. Threads that
31 * are found to allocate lots of memory are given bigger fragments. This
32 * should make the finalizer thread use little nursery memory after a while.
33 * We should start assigning threads very small fragments: if there are many
34 * threads the nursery will be full of reserved space that the threads may not
35 * use at all, slowing down allocation speed.
36 * Thread local allocation is done from areas of memory Hotspot calls Thread Local
37 * Allocation Buffers (TLABs).
48 #ifdef HAVE_SEMAPHORE_H
49 #include <semaphore.h>
62 #include "mono/metadata/sgen-gc.h"
63 #include "mono/metadata/sgen-cardtable.h"
64 #include "mono/metadata/sgen-protocol.h"
65 #include "mono/metadata/sgen-memory-governor.h"
66 #include "mono/metadata/sgen-pinning.h"
67 #include "mono/metadata/sgen-client.h"
68 #include "mono/utils/mono-membar.h"
70 /* Enable it so nursery allocation diagnostic data is collected */
71 //#define NALLOC_DEBUG 1
73 /* The mutator allocs from here. */
74 static SgenFragmentAllocator mutator_allocator;
76 /* freeelist of fragment structures */
77 static SgenFragment *fragment_freelist = NULL;
79 /* Allocator cursors */
80 static char *nursery_last_pinned_end = NULL;
82 char *sgen_nursery_start;
83 char *sgen_nursery_end;
86 size_t sgen_nursery_size = (1 << 22);
87 int sgen_nursery_bits = 22;
90 char *sgen_space_bitmap;
91 size_t sgen_space_bitmap_size;
93 #ifdef HEAVY_STATISTICS
95 static mword stat_wasted_bytes_trailer = 0;
96 static mword stat_wasted_bytes_small_areas = 0;
97 static mword stat_wasted_bytes_discarded_fragments = 0;
98 static guint64 stat_nursery_alloc_requests = 0;
99 static guint64 stat_alloc_iterations = 0;
100 static guint64 stat_alloc_retries = 0;
102 static guint64 stat_nursery_alloc_range_requests = 0;
103 static guint64 stat_alloc_range_iterations = 0;
104 static guint64 stat_alloc_range_retries = 0;
108 /************************************Nursery allocation debugging *********************************************/
125 MonoNativeThreadId tid;
128 #define ALLOC_RECORD_COUNT 128000
131 static AllocRecord *alloc_records;
132 static volatile int next_record;
133 static volatile int alloc_count;
135 void dump_alloc_records (void);
136 void verify_alloc_records (void);
139 get_reason_name (AllocRecord *rec)
141 switch (rec->reason) {
142 case FIXED_ALLOC: return "fixed-alloc";
143 case RANGE_ALLOC: return "range-alloc";
144 case PINNING: return "pinning";
145 case BLOCK_ZEROING: return "block-zeroing";
146 case CLEAR_NURSERY_FRAGS: return "clear-nursery-frag";
147 default: return "invalid";
152 reset_alloc_records (void)
159 add_alloc_record (char *addr, size_t size, int reason)
161 int idx = InterlockedIncrement (&next_record) - 1;
162 alloc_records [idx].address = addr;
163 alloc_records [idx].size = size;
164 alloc_records [idx].reason = reason;
165 alloc_records [idx].seq = idx;
166 alloc_records [idx].tid = mono_native_thread_id_get ();
170 comp_alloc_record (const void *_a, const void *_b)
172 const AllocRecord *a = _a;
173 const AllocRecord *b = _b;
174 if (a->address == b->address)
175 return a->seq - b->seq;
176 return a->address - b->address;
179 #define rec_end(REC) ((REC)->address + (REC)->size)
182 dump_alloc_records (void)
185 sgen_qsort (alloc_records, next_record, sizeof (AllocRecord), comp_alloc_record);
187 printf ("------------------------------------DUMP RECORDS----------------------------\n");
188 for (i = 0; i < next_record; ++i) {
189 AllocRecord *rec = alloc_records + i;
190 printf ("obj [%p, %p] size %d reason %s seq %d tid %x\n", rec->address, rec_end (rec), (int)rec->size, get_reason_name (rec), rec->seq, (size_t)rec->tid);
195 verify_alloc_records (void)
201 AllocRecord *prev = NULL;
203 sgen_qsort (alloc_records, next_record, sizeof (AllocRecord), comp_alloc_record);
204 printf ("------------------------------------DUMP RECORDS- %d %d---------------------------\n", next_record, alloc_count);
205 for (i = 0; i < next_record; ++i) {
206 AllocRecord *rec = alloc_records + i;
210 if (rec_end (prev) > rec->address)
211 printf ("WE GOT OVERLAPPING objects %p and %p\n", prev->address, rec->address);
212 if ((rec->address - rec_end (prev)) >= 8)
214 hole_size = rec->address - rec_end (prev);
215 max_hole = MAX (max_hole, hole_size);
217 printf ("obj [%p, %p] size %d hole to prev %d reason %s seq %d tid %zx\n", rec->address, rec_end (rec), (int)rec->size, hole_size, get_reason_name (rec), rec->seq, (size_t)rec->tid);
220 printf ("SUMMARY total alloc'd %d holes %d max_hole %d\n", total, holes, max_hole);
225 /*********************************************************************************/
228 static inline gpointer
229 mask (gpointer n, uintptr_t bit)
231 return (gpointer)(((uintptr_t)n) | bit);
234 static inline gpointer
237 return (gpointer)((uintptr_t)p & ~(uintptr_t)0x3);
240 static inline uintptr_t
241 get_mark (gpointer n)
243 return (uintptr_t)n & 0x1;
246 /*MUST be called with world stopped*/
248 sgen_fragment_allocator_alloc (void)
250 SgenFragment *frag = fragment_freelist;
252 fragment_freelist = frag->next_in_order;
253 frag->next = frag->next_in_order = NULL;
256 frag = sgen_alloc_internal (INTERNAL_MEM_FRAGMENT);
257 frag->next = frag->next_in_order = NULL;
262 sgen_fragment_allocator_add (SgenFragmentAllocator *allocator, char *start, char *end)
264 SgenFragment *fragment;
266 fragment = sgen_fragment_allocator_alloc ();
267 fragment->fragment_start = start;
268 fragment->fragment_next = start;
269 fragment->fragment_end = end;
270 fragment->next_in_order = fragment->next = unmask (allocator->region_head);
272 allocator->region_head = allocator->alloc_head = fragment;
273 g_assert (fragment->fragment_end > fragment->fragment_start);
277 sgen_fragment_allocator_release (SgenFragmentAllocator *allocator)
279 SgenFragment *last = allocator->region_head;
283 /* Find the last fragment in insert order */
284 for (; last->next_in_order; last = last->next_in_order) ;
286 last->next_in_order = fragment_freelist;
287 fragment_freelist = allocator->region_head;
288 allocator->alloc_head = allocator->region_head = NULL;
291 static SgenFragment**
292 find_previous_pointer_fragment (SgenFragmentAllocator *allocator, SgenFragment *frag)
295 SgenFragment *cur, *next;
301 prev = &allocator->alloc_head;
304 printf ("retry count for fppf is %d\n", count);
307 cur = unmask (*prev);
315 * We need to make sure that we dereference prev below
316 * after reading cur->next above, so we need a read
319 mono_memory_read_barrier ();
324 if (!get_mark (next)) {
329 next = unmask (next);
330 if (InterlockedCompareExchangePointer ((volatile gpointer*)prev, next, cur) != cur)
332 /*we must make sure that the next from cur->next happens after*/
333 mono_memory_write_barrier ();
342 claim_remaining_size (SgenFragment *frag, char *alloc_end)
344 /* All space used, nothing to claim. */
345 if (frag->fragment_end <= alloc_end)
348 /* Try to alloc all the remaining space. */
349 return InterlockedCompareExchangePointer ((volatile gpointer*)&frag->fragment_next, frag->fragment_end, alloc_end) == alloc_end;
353 par_alloc_from_fragment (SgenFragmentAllocator *allocator, SgenFragment *frag, size_t size)
355 char *p = frag->fragment_next;
356 char *end = p + size;
358 if (end > frag->fragment_end)
361 /* p = frag->fragment_next must happen before */
362 mono_memory_barrier ();
364 if (InterlockedCompareExchangePointer ((volatile gpointer*)&frag->fragment_next, end, p) != p)
367 if (frag->fragment_end - end < SGEN_MAX_NURSERY_WASTE) {
368 SgenFragment *next, **prev_ptr;
371 * Before we clean the remaining nursery, we must claim the remaining space
372 * as it could end up been used by the range allocator since it can end up
373 * allocating from this dying fragment as it doesn't respect SGEN_MAX_NURSERY_WASTE
374 * when doing second chance allocation.
376 if ((sgen_get_nursery_clear_policy () == CLEAR_AT_TLAB_CREATION || sgen_get_nursery_clear_policy () == CLEAR_AT_TLAB_CREATION_DEBUG) && claim_remaining_size (frag, end)) {
377 sgen_clear_range (end, frag->fragment_end);
378 HEAVY_STAT (InterlockedExchangeAdd (&stat_wasted_bytes_trailer, frag->fragment_end - end));
380 add_alloc_record (end, frag->fragment_end - end, BLOCK_ZEROING);
384 prev_ptr = find_previous_pointer_fragment (allocator, frag);
386 /*Use Michaels linked list remove*/
388 /*prev_ptr will be null if the fragment was removed concurrently */
393 if (!get_mark (next)) {
394 /*frag->next read must happen before the first CAS*/
395 mono_memory_write_barrier ();
397 /*Fail if the next node is removed concurrently and its CAS wins */
398 if (InterlockedCompareExchangePointer ((volatile gpointer*)&frag->next, mask (next, 1), next) != next) {
403 /* The second CAS must happen after the first CAS or frag->next. */
404 mono_memory_write_barrier ();
406 /* Fail if the previous node was deleted and its CAS wins */
407 if (InterlockedCompareExchangePointer ((volatile gpointer*)prev_ptr, unmask (next), frag) != frag) {
408 prev_ptr = find_previous_pointer_fragment (allocator, frag);
419 serial_alloc_from_fragment (SgenFragment **previous, SgenFragment *frag, size_t size)
421 char *p = frag->fragment_next;
422 char *end = p + size;
424 if (end > frag->fragment_end)
427 frag->fragment_next = end;
429 if (frag->fragment_end - end < SGEN_MAX_NURSERY_WASTE) {
430 *previous = frag->next;
432 /* Clear the remaining space, pinning depends on this. FIXME move this to use phony arrays */
433 memset (end, 0, frag->fragment_end - end);
435 *previous = frag->next;
442 sgen_fragment_allocator_par_alloc (SgenFragmentAllocator *allocator, size_t size)
447 InterlockedIncrement (&alloc_count);
451 for (frag = unmask (allocator->alloc_head); unmask (frag); frag = unmask (frag->next)) {
452 HEAVY_STAT (InterlockedIncrement (&stat_alloc_iterations));
454 if (size <= (size_t)(frag->fragment_end - frag->fragment_next)) {
455 void *p = par_alloc_from_fragment (allocator, frag, size);
457 HEAVY_STAT (InterlockedIncrement (&stat_alloc_retries));
461 add_alloc_record (p, size, FIXED_ALLOC);
470 sgen_fragment_allocator_serial_alloc (SgenFragmentAllocator *allocator, size_t size)
473 SgenFragment **previous;
475 InterlockedIncrement (&alloc_count);
478 previous = &allocator->alloc_head;
480 for (frag = *previous; frag; frag = *previous) {
481 char *p = serial_alloc_from_fragment (previous, frag, size);
483 HEAVY_STAT (InterlockedIncrement (&stat_alloc_iterations));
487 add_alloc_record (p, size, FIXED_ALLOC);
491 previous = &frag->next;
497 sgen_fragment_allocator_serial_range_alloc (SgenFragmentAllocator *allocator, size_t desired_size, size_t minimum_size, size_t *out_alloc_size)
499 SgenFragment *frag, **previous, *min_frag = NULL, **prev_min_frag = NULL;
500 size_t current_minimum = minimum_size;
503 InterlockedIncrement (&alloc_count);
506 previous = &allocator->alloc_head;
508 for (frag = *previous; frag; frag = *previous) {
509 size_t frag_size = frag->fragment_end - frag->fragment_next;
511 HEAVY_STAT (InterlockedIncrement (&stat_alloc_range_iterations));
513 if (desired_size <= frag_size) {
515 *out_alloc_size = desired_size;
517 p = serial_alloc_from_fragment (previous, frag, desired_size);
519 add_alloc_record (p, desired_size, RANGE_ALLOC);
523 if (current_minimum <= frag_size) {
525 prev_min_frag = previous;
526 current_minimum = frag_size;
528 previous = &frag->next;
533 size_t frag_size = min_frag->fragment_end - min_frag->fragment_next;
534 *out_alloc_size = frag_size;
536 p = serial_alloc_from_fragment (prev_min_frag, min_frag, frag_size);
539 add_alloc_record (p, frag_size, RANGE_ALLOC);
548 sgen_fragment_allocator_par_range_alloc (SgenFragmentAllocator *allocator, size_t desired_size, size_t minimum_size, size_t *out_alloc_size)
550 SgenFragment *frag, *min_frag;
551 size_t current_minimum;
555 current_minimum = minimum_size;
558 InterlockedIncrement (&alloc_count);
561 for (frag = unmask (allocator->alloc_head); frag; frag = unmask (frag->next)) {
562 size_t frag_size = frag->fragment_end - frag->fragment_next;
564 HEAVY_STAT (InterlockedIncrement (&stat_alloc_range_iterations));
566 if (desired_size <= frag_size) {
568 *out_alloc_size = desired_size;
570 p = par_alloc_from_fragment (allocator, frag, desired_size);
572 HEAVY_STAT (InterlockedIncrement (&stat_alloc_range_retries));
576 add_alloc_record (p, desired_size, RANGE_ALLOC);
580 if (current_minimum <= frag_size) {
582 current_minimum = frag_size;
586 /* The second fragment_next read should be ordered in respect to the first code block */
587 mono_memory_barrier ();
593 frag_size = min_frag->fragment_end - min_frag->fragment_next;
594 if (frag_size < minimum_size)
597 *out_alloc_size = frag_size;
599 mono_memory_barrier ();
600 p = par_alloc_from_fragment (allocator, min_frag, frag_size);
602 /*XXX restarting here is quite dubious given this is already second chance allocation. */
604 HEAVY_STAT (InterlockedIncrement (&stat_alloc_retries));
608 add_alloc_record (p, frag_size, RANGE_ALLOC);
617 sgen_clear_allocator_fragments (SgenFragmentAllocator *allocator)
621 for (frag = unmask (allocator->alloc_head); frag; frag = unmask (frag->next)) {
622 SGEN_LOG (4, "Clear nursery frag %p-%p", frag->fragment_next, frag->fragment_end);
623 sgen_clear_range (frag->fragment_next, frag->fragment_end);
625 add_alloc_record (frag->fragment_next, frag->fragment_end - frag->fragment_next, CLEAR_NURSERY_FRAGS);
630 /* Clear all remaining nursery fragments */
632 sgen_clear_nursery_fragments (void)
634 if (sgen_get_nursery_clear_policy () == CLEAR_AT_TLAB_CREATION || sgen_get_nursery_clear_policy () == CLEAR_AT_TLAB_CREATION_DEBUG) {
635 sgen_clear_allocator_fragments (&mutator_allocator);
636 sgen_minor_collector.clear_fragments ();
641 * Mark a given range of memory as invalid.
643 * This can be done either by zeroing memory or by placing
644 * a phony byte[] array. This keeps the heap forward walkable.
646 * This function ignores calls with a zero range, even if
647 * both start and end are NULL.
650 sgen_clear_range (char *start, char *end)
652 size_t size = end - start;
654 if ((start && !end) || (start > end))
655 g_error ("Invalid range [%p %p]", start, end);
657 if (sgen_client_array_fill_range (start, size)) {
658 sgen_set_nursery_scan_start (start);
659 SGEN_ASSERT (0, start + sgen_safe_object_get_size ((GCObject*)start) == end, "Array fill produced wrong size");
664 sgen_nursery_allocator_prepare_for_pinning (void)
666 sgen_clear_allocator_fragments (&mutator_allocator);
667 sgen_minor_collector.clear_fragments ();
670 static mword fragment_total = 0;
672 * We found a fragment of free memory in the nursery: memzero it and if
673 * it is big enough, add it to the list of fragments that can be used for
677 add_nursery_frag (SgenFragmentAllocator *allocator, size_t frag_size, char* frag_start, char* frag_end)
679 SGEN_LOG (4, "Found empty fragment: %p-%p, size: %zd", frag_start, frag_end, frag_size);
680 binary_protocol_empty (frag_start, frag_size);
681 /* Not worth dealing with smaller fragments: need to tune */
682 if (frag_size >= SGEN_MAX_NURSERY_WASTE) {
683 /* memsetting just the first chunk start is bound to provide better cache locality */
684 if (sgen_get_nursery_clear_policy () == CLEAR_AT_GC)
685 memset (frag_start, 0, frag_size);
686 else if (sgen_get_nursery_clear_policy () == CLEAR_AT_TLAB_CREATION_DEBUG)
687 memset (frag_start, 0xff, frag_size);
690 /* XXX convert this into a flight record entry
691 printf ("\tfragment [%p %p] size %zd\n", frag_start, frag_end, frag_size);
694 sgen_fragment_allocator_add (allocator, frag_start, frag_end);
695 fragment_total += frag_size;
697 /* Clear unused fragments, pinning depends on this */
698 sgen_clear_range (frag_start, frag_end);
699 HEAVY_STAT (InterlockedExchangeAdd (&stat_wasted_bytes_small_areas, frag_size));
704 fragment_list_reverse (SgenFragmentAllocator *allocator)
706 SgenFragment *prev = NULL, *list = allocator->region_head;
708 SgenFragment *next = list->next;
710 list->next_in_order = prev;
715 allocator->region_head = allocator->alloc_head = prev;
719 sgen_build_nursery_fragments (GCMemSection *nursery_section, SgenGrayQueue *unpin_queue)
721 char *frag_start, *frag_end;
723 SgenFragment *frags_ranges;
724 void **pin_start, **pin_entry, **pin_end;
727 reset_alloc_records ();
729 /*The mutator fragments are done. We no longer need them. */
730 sgen_fragment_allocator_release (&mutator_allocator);
732 frag_start = sgen_nursery_start;
735 /* The current nursery might give us a fragment list to exclude [start, next[*/
736 frags_ranges = sgen_minor_collector.build_fragments_get_exclude_head ();
738 /* clear scan starts */
739 memset (nursery_section->scan_starts, 0, nursery_section->num_scan_start * sizeof (gpointer));
741 pin_start = pin_entry = sgen_pinning_get_entry (nursery_section->pin_queue_first_entry);
742 pin_end = sgen_pinning_get_entry (nursery_section->pin_queue_last_entry);
744 while (pin_entry < pin_end || frags_ranges) {
748 addr0 = addr1 = sgen_nursery_end;
749 if (pin_entry < pin_end)
752 addr1 = frags_ranges->fragment_start;
756 GRAY_OBJECT_ENQUEUE (unpin_queue, addr0, sgen_obj_get_descriptor_safe (addr0));
758 SGEN_UNPIN_OBJECT (addr0);
759 size = SGEN_ALIGN_UP (sgen_safe_object_get_size ((GCObject*)addr0));
760 CANARIFY_SIZE (size);
761 sgen_set_nursery_scan_start (addr0);
766 size = frags_ranges->fragment_next - addr1;
767 frags_ranges = frags_ranges->next_in_order;
770 frag_size = frag_end - frag_start;
775 g_assert (frag_size >= 0);
777 if (frag_size && size)
778 add_nursery_frag (&mutator_allocator, frag_size, frag_start, frag_end);
782 add_alloc_record (*pin_entry, frag_size, PINNING);
784 frag_start = frag_end + frag_size;
787 nursery_last_pinned_end = frag_start;
788 frag_end = sgen_nursery_end;
789 frag_size = frag_end - frag_start;
791 add_nursery_frag (&mutator_allocator, frag_size, frag_start, frag_end);
793 /* Now it's safe to release the fragments exclude list. */
794 sgen_minor_collector.build_fragments_release_exclude_head ();
796 /* First we reorder the fragment list to be in ascending address order. This makes H/W prefetchers happier. */
797 fragment_list_reverse (&mutator_allocator);
799 /*The collector might want to do something with the final nursery fragment list.*/
800 sgen_minor_collector.build_fragments_finish (&mutator_allocator);
802 if (!unmask (mutator_allocator.alloc_head)) {
803 SGEN_LOG (1, "Nursery fully pinned");
804 for (pin_entry = pin_start; pin_entry < pin_end; ++pin_entry) {
805 void *p = *pin_entry;
806 SGEN_LOG (3, "Bastard pinning obj %p (%s), size: %zd", p, sgen_client_vtable_get_name (SGEN_LOAD_VTABLE (p)), sgen_safe_object_get_size (p));
809 return fragment_total;
813 sgen_nursery_alloc_get_upper_alloc_bound (void)
815 /*FIXME we need to calculate the collector upper bound as well, but this must be done in the previous GC. */
816 return sgen_nursery_end;
819 /*** Nursery memory allocation ***/
821 sgen_nursery_retire_region (void *address, ptrdiff_t size)
823 HEAVY_STAT (InterlockedExchangeAdd (&stat_wasted_bytes_discarded_fragments, size));
827 sgen_can_alloc_size (size_t size)
831 if (!SGEN_CAN_ALIGN_UP (size))
834 size = SGEN_ALIGN_UP (size);
836 for (frag = unmask (mutator_allocator.alloc_head); frag; frag = unmask (frag->next)) {
837 if ((size_t)(frag->fragment_end - frag->fragment_next) >= size)
844 sgen_nursery_alloc (size_t size)
846 SGEN_ASSERT (1, size >= (SGEN_CLIENT_MINIMUM_OBJECT_SIZE + CANARY_SIZE) && size <= (SGEN_MAX_SMALL_OBJ_SIZE + CANARY_SIZE), "Invalid nursery object size");
848 SGEN_LOG (4, "Searching nursery for size: %zd", size);
849 size = SGEN_ALIGN_UP (size);
851 HEAVY_STAT (InterlockedIncrement (&stat_nursery_alloc_requests));
853 return sgen_fragment_allocator_par_alloc (&mutator_allocator, size);
857 sgen_nursery_alloc_range (size_t desired_size, size_t minimum_size, size_t *out_alloc_size)
859 SGEN_LOG (4, "Searching for byte range desired size: %zd minimum size %zd", desired_size, minimum_size);
861 HEAVY_STAT (InterlockedIncrement (&stat_nursery_alloc_range_requests));
863 return sgen_fragment_allocator_par_range_alloc (&mutator_allocator, desired_size, minimum_size, out_alloc_size);
866 /*** Initialization ***/
868 #ifdef HEAVY_STATISTICS
871 sgen_nursery_allocator_init_heavy_stats (void)
873 mono_counters_register ("bytes wasted trailer fragments", MONO_COUNTER_GC | MONO_COUNTER_WORD | MONO_COUNTER_BYTES, &stat_wasted_bytes_trailer);
874 mono_counters_register ("bytes wasted small areas", MONO_COUNTER_GC | MONO_COUNTER_WORD | MONO_COUNTER_BYTES, &stat_wasted_bytes_small_areas);
875 mono_counters_register ("bytes wasted discarded fragments", MONO_COUNTER_GC | MONO_COUNTER_WORD | MONO_COUNTER_BYTES, &stat_wasted_bytes_discarded_fragments);
877 mono_counters_register ("# nursery alloc requests", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_nursery_alloc_requests);
878 mono_counters_register ("# nursery alloc iterations", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_alloc_iterations);
879 mono_counters_register ("# nursery alloc retries", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_alloc_retries);
881 mono_counters_register ("# nursery alloc range requests", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_nursery_alloc_range_requests);
882 mono_counters_register ("# nursery alloc range iterations", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_alloc_range_iterations);
883 mono_counters_register ("# nursery alloc range restries", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_alloc_range_retries);
889 sgen_init_nursery_allocator (void)
891 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_FRAGMENT, sizeof (SgenFragment));
893 alloc_records = sgen_alloc_os_memory (sizeof (AllocRecord) * ALLOC_RECORD_COUNT, SGEN_ALLOC_INTERNAL | SGEN_ALLOC_ACTIVATE, "debugging memory");
898 sgen_nursery_alloc_prepare_for_minor (void)
900 sgen_minor_collector.prepare_to_space (sgen_space_bitmap, sgen_space_bitmap_size);
904 sgen_nursery_alloc_prepare_for_major (void)
906 sgen_minor_collector.prepare_to_space (sgen_space_bitmap, sgen_space_bitmap_size);
910 sgen_nursery_allocator_set_nursery_bounds (char *start, char *end)
912 sgen_nursery_start = start;
913 sgen_nursery_end = end;
916 * This will not divide evenly for tiny nurseries (<4kb), so we make sure to be on
917 * the right side of things and round up. We could just do a MIN(1,x) instead,
918 * since the nursery size must be a power of 2.
920 sgen_space_bitmap_size = (end - start + SGEN_TO_SPACE_GRANULE_IN_BYTES * 8 - 1) / (SGEN_TO_SPACE_GRANULE_IN_BYTES * 8);
921 sgen_space_bitmap = g_malloc0 (sgen_space_bitmap_size);
923 /* Setup the single first large fragment */
924 sgen_minor_collector.init_nursery (&mutator_allocator, start, end);