2 * sgen-gc.c: Simple generational GC.
5 * Paolo Molaro (lupus@ximian.com)
6 * Rodrigo Kumpera (kumpera@gmail.com)
8 * Copyright 2005-2011 Novell, Inc (http://www.novell.com)
9 * Copyright 2011 Xamarin Inc (http://www.xamarin.com)
11 * Thread start/stop adapted from Boehm's GC:
12 * Copyright (c) 1994 by Xerox Corporation. All rights reserved.
13 * Copyright (c) 1996 by Silicon Graphics. All rights reserved.
14 * Copyright (c) 1998 by Fergus Henderson. All rights reserved.
15 * Copyright (c) 2000-2004 by Hewlett-Packard Company. All rights reserved.
16 * Copyright 2001-2003 Ximian, Inc
17 * Copyright 2003-2010 Novell, Inc.
18 * Copyright 2011 Xamarin, Inc.
19 * Copyright (C) 2012 Xamarin Inc
21 * This library is free software; you can redistribute it and/or
22 * modify it under the terms of the GNU Library General Public
23 * License 2.0 as published by the Free Software Foundation;
25 * This library is distributed in the hope that it will be useful,
26 * but WITHOUT ANY WARRANTY; without even the implied warranty of
27 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
28 * Library General Public License for more details.
30 * You should have received a copy of the GNU Library General Public
31 * License 2.0 along with this library; if not, write to the Free
32 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
34 * Important: allocation provides always zeroed memory, having to do
35 * a memset after allocation is deadly for performance.
36 * Memory usage at startup is currently as follows:
38 * 64 KB internal space
40 * We should provide a small memory config with half the sizes
42 * We currently try to make as few mono assumptions as possible:
43 * 1) 2-word header with no GC pointers in it (first vtable, second to store the
45 * 2) gc descriptor is the second word in the vtable (first word in the class)
46 * 3) 8 byte alignment is the minimum and enough (not true for special structures (SIMD), FIXME)
47 * 4) there is a function to get an object's size and the number of
48 * elements in an array.
49 * 5) we know the special way bounds are allocated for complex arrays
50 * 6) we know about proxies and how to treat them when domains are unloaded
52 * Always try to keep stack usage to a minimum: no recursive behaviour
53 * and no large stack allocs.
55 * General description.
56 * Objects are initially allocated in a nursery using a fast bump-pointer technique.
57 * When the nursery is full we start a nursery collection: this is performed with a
59 * When the old generation is full we start a copying GC of the old generation as well:
60 * this will be changed to mark&sweep with copying when fragmentation becomes to severe
61 * in the future. Maybe we'll even do both during the same collection like IMMIX.
63 * The things that complicate this description are:
64 * *) pinned objects: we can't move them so we need to keep track of them
65 * *) no precise info of the thread stacks and registers: we need to be able to
66 * quickly find the objects that may be referenced conservatively and pin them
67 * (this makes the first issues more important)
68 * *) large objects are too expensive to be dealt with using copying GC: we handle them
69 * with mark/sweep during major collections
70 * *) some objects need to not move even if they are small (interned strings, Type handles):
71 * we use mark/sweep for them, too: they are not allocated in the nursery, but inside
72 * PinnedChunks regions
78 *) we could have a function pointer in MonoClass to implement
79 customized write barriers for value types
81 *) investigate the stuff needed to advance a thread to a GC-safe
82 point (single-stepping, read from unmapped memory etc) and implement it.
83 This would enable us to inline allocations and write barriers, for example,
84 or at least parts of them, like the write barrier checks.
85 We may need this also for handling precise info on stacks, even simple things
86 as having uninitialized data on the stack and having to wait for the prolog
87 to zero it. Not an issue for the last frame that we scan conservatively.
88 We could always not trust the value in the slots anyway.
90 *) modify the jit to save info about references in stack locations:
91 this can be done just for locals as a start, so that at least
92 part of the stack is handled precisely.
94 *) test/fix endianess issues
96 *) Implement a card table as the write barrier instead of remembered
97 sets? Card tables are not easy to implement with our current
98 memory layout. We have several different kinds of major heap
99 objects: Small objects in regular blocks, small objects in pinned
100 chunks and LOS objects. If we just have a pointer we have no way
101 to tell which kind of object it points into, therefore we cannot
102 know where its card table is. The least we have to do to make
103 this happen is to get rid of write barriers for indirect stores.
106 *) Get rid of write barriers for indirect stores. We can do this by
107 telling the GC to wbarrier-register an object once we do an ldloca
108 or ldelema on it, and to unregister it once it's not used anymore
109 (it can only travel downwards on the stack). The problem with
110 unregistering is that it needs to happen eventually no matter
111 what, even if exceptions are thrown, the thread aborts, etc.
112 Rodrigo suggested that we could do only the registering part and
113 let the collector find out (pessimistically) when it's safe to
114 unregister, namely when the stack pointer of the thread that
115 registered the object is higher than it was when the registering
116 happened. This might make for a good first implementation to get
117 some data on performance.
119 *) Some sort of blacklist support? Blacklists is a concept from the
120 Boehm GC: if during a conservative scan we find pointers to an
121 area which we might use as heap, we mark that area as unusable, so
122 pointer retention by random pinning pointers is reduced.
124 *) experiment with max small object size (very small right now - 2kb,
125 because it's tied to the max freelist size)
127 *) add an option to mmap the whole heap in one chunk: it makes for many
128 simplifications in the checks (put the nursery at the top and just use a single
129 check for inclusion/exclusion): the issue this has is that on 32 bit systems it's
130 not flexible (too much of the address space may be used by default or we can't
131 increase the heap as needed) and we'd need a race-free mechanism to return memory
132 back to the system (mprotect(PROT_NONE) will still keep the memory allocated if it
133 was written to, munmap is needed, but the following mmap may not find the same segment
136 *) memzero the major fragments after restarting the world and optionally a smaller
139 *) investigate having fragment zeroing threads
141 *) separate locks for finalization and other minor stuff to reduce
144 *) try a different copying order to improve memory locality
146 *) a thread abort after a store but before the write barrier will
147 prevent the write barrier from executing
149 *) specialized dynamically generated markers/copiers
151 *) Dynamically adjust TLAB size to the number of threads. If we have
152 too many threads that do allocation, we might need smaller TLABs,
153 and we might get better performance with larger TLABs if we only
154 have a handful of threads. We could sum up the space left in all
155 assigned TLABs and if that's more than some percentage of the
156 nursery size, reduce the TLAB size.
158 *) Explore placing unreachable objects on unused nursery memory.
159 Instead of memset'ng a region to zero, place an int[] covering it.
160 A good place to start is add_nursery_frag. The tricky thing here is
161 placing those objects atomically outside of a collection.
163 *) Allocation should use asymmetric Dekker synchronization:
164 http://blogs.oracle.com/dave/resource/Asymmetric-Dekker-Synchronization.txt
165 This should help weak consistency archs.
172 #define _XOPEN_SOURCE
173 #define _DARWIN_C_SOURCE
179 #ifdef HAVE_PTHREAD_H
182 #ifdef HAVE_SEMAPHORE_H
183 #include <semaphore.h>
191 #include "metadata/sgen-gc.h"
192 #include "metadata/metadata-internals.h"
193 #include "metadata/class-internals.h"
194 #include "metadata/gc-internal.h"
195 #include "metadata/object-internals.h"
196 #include "metadata/threads.h"
197 #include "metadata/sgen-cardtable.h"
198 #include "metadata/sgen-ssb.h"
199 #include "metadata/sgen-protocol.h"
200 #include "metadata/sgen-archdep.h"
201 #include "metadata/sgen-bridge.h"
202 #include "metadata/sgen-memory-governor.h"
203 #include "metadata/sgen-hash-table.h"
204 #include "metadata/mono-gc.h"
205 #include "metadata/method-builder.h"
206 #include "metadata/profiler-private.h"
207 #include "metadata/monitor.h"
208 #include "metadata/threadpool-internals.h"
209 #include "metadata/mempool-internals.h"
210 #include "metadata/marshal.h"
211 #include "metadata/runtime.h"
212 #include "metadata/sgen-cardtable.h"
213 #include "metadata/sgen-pinning.h"
214 #include "metadata/sgen-workers.h"
215 #include "utils/mono-mmap.h"
216 #include "utils/mono-time.h"
217 #include "utils/mono-semaphore.h"
218 #include "utils/mono-counters.h"
219 #include "utils/mono-proclib.h"
220 #include "utils/mono-memory-model.h"
221 #include "utils/mono-logger-internal.h"
222 #include "utils/dtrace.h"
224 #include <mono/utils/mono-logger-internal.h>
225 #include <mono/utils/memcheck.h>
227 #if defined(__MACH__)
228 #include "utils/mach-support.h"
231 #define OPDEF(a,b,c,d,e,f,g,h,i,j) \
235 #include "mono/cil/opcode.def"
241 #undef pthread_create
243 #undef pthread_detach
246 * ######################################################################
247 * ######## Types and constants used by the GC.
248 * ######################################################################
251 /* 0 means not initialized, 1 is initialized, -1 means in progress */
252 static int gc_initialized = 0;
253 /* If set, check if we need to do something every X allocations */
254 gboolean has_per_allocation_action;
255 /* If set, do a heap check every X allocation */
256 guint32 verify_before_allocs = 0;
257 /* If set, do a minor collection before every X allocation */
258 guint32 collect_before_allocs = 0;
259 /* If set, do a whole heap check before each collection */
260 static gboolean whole_heap_check_before_collection = FALSE;
261 /* If set, do a heap consistency check before each minor collection */
262 static gboolean consistency_check_at_minor_collection = FALSE;
263 /* If set, check that there are no references to the domain left at domain unload */
264 static gboolean xdomain_checks = FALSE;
265 /* If not null, dump the heap after each collection into this file */
266 static FILE *heap_dump_file = NULL;
267 /* If set, mark stacks conservatively, even if precise marking is possible */
268 static gboolean conservative_stack_mark = FALSE;
269 /* If set, do a plausibility check on the scan_starts before and after
271 static gboolean do_scan_starts_check = FALSE;
272 static gboolean nursery_collection_is_parallel = FALSE;
273 static gboolean disable_minor_collections = FALSE;
274 static gboolean disable_major_collections = FALSE;
275 gboolean do_pin_stats = FALSE;
276 static gboolean do_verify_nursery = FALSE;
277 static gboolean do_dump_nursery_content = FALSE;
279 #ifdef HEAVY_STATISTICS
280 long long stat_objects_alloced_degraded = 0;
281 long long stat_bytes_alloced_degraded = 0;
283 long long stat_copy_object_called_nursery = 0;
284 long long stat_objects_copied_nursery = 0;
285 long long stat_copy_object_called_major = 0;
286 long long stat_objects_copied_major = 0;
288 long long stat_scan_object_called_nursery = 0;
289 long long stat_scan_object_called_major = 0;
291 long long stat_slots_allocated_in_vain;
293 long long stat_nursery_copy_object_failed_from_space = 0;
294 long long stat_nursery_copy_object_failed_forwarded = 0;
295 long long stat_nursery_copy_object_failed_pinned = 0;
296 long long stat_nursery_copy_object_failed_to_space = 0;
298 static int stat_wbarrier_set_field = 0;
299 static int stat_wbarrier_set_arrayref = 0;
300 static int stat_wbarrier_arrayref_copy = 0;
301 static int stat_wbarrier_generic_store = 0;
302 static int stat_wbarrier_set_root = 0;
303 static int stat_wbarrier_value_copy = 0;
304 static int stat_wbarrier_object_copy = 0;
307 int stat_minor_gcs = 0;
308 int stat_major_gcs = 0;
310 static long long stat_pinned_objects = 0;
312 static long long time_minor_pre_collection_fragment_clear = 0;
313 static long long time_minor_pinning = 0;
314 static long long time_minor_scan_remsets = 0;
315 static long long time_minor_scan_pinned = 0;
316 static long long time_minor_scan_registered_roots = 0;
317 static long long time_minor_scan_thread_data = 0;
318 static long long time_minor_finish_gray_stack = 0;
319 static long long time_minor_fragment_creation = 0;
321 static long long time_major_pre_collection_fragment_clear = 0;
322 static long long time_major_pinning = 0;
323 static long long time_major_scan_pinned = 0;
324 static long long time_major_scan_registered_roots = 0;
325 static long long time_major_scan_thread_data = 0;
326 static long long time_major_scan_alloc_pinned = 0;
327 static long long time_major_scan_finalized = 0;
328 static long long time_major_scan_big_objects = 0;
329 static long long time_major_finish_gray_stack = 0;
330 static long long time_major_free_bigobjs = 0;
331 static long long time_major_los_sweep = 0;
332 static long long time_major_sweep = 0;
333 static long long time_major_fragment_creation = 0;
335 int gc_debug_level = 0;
340 mono_gc_flush_info (void)
342 fflush (gc_debug_file);
346 #define TV_DECLARE SGEN_TV_DECLARE
347 #define TV_GETTIME SGEN_TV_GETTIME
348 #define TV_ELAPSED SGEN_TV_ELAPSED
349 #define TV_ELAPSED_MS SGEN_TV_ELAPSED_MS
351 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
353 NurseryClearPolicy nursery_clear_policy = CLEAR_AT_TLAB_CREATION;
355 #define object_is_forwarded SGEN_OBJECT_IS_FORWARDED
356 #define object_is_pinned SGEN_OBJECT_IS_PINNED
357 #define pin_object SGEN_PIN_OBJECT
358 #define unpin_object SGEN_UNPIN_OBJECT
360 #define ptr_in_nursery sgen_ptr_in_nursery
362 #define LOAD_VTABLE SGEN_LOAD_VTABLE
365 safe_name (void* obj)
367 MonoVTable *vt = (MonoVTable*)LOAD_VTABLE (obj);
368 return vt->klass->name;
371 #define safe_object_get_size sgen_safe_object_get_size
374 sgen_safe_name (void* obj)
376 return safe_name (obj);
380 * ######################################################################
381 * ######## Global data.
382 * ######################################################################
384 LOCK_DECLARE (gc_mutex);
385 static int gc_disabled = 0;
387 static gboolean use_cardtable;
389 #define SCAN_START_SIZE SGEN_SCAN_START_SIZE
391 static mword pagesize = 4096;
392 int degraded_mode = 0;
394 static mword bytes_pinned_from_failed_allocation = 0;
396 GCMemSection *nursery_section = NULL;
397 static mword lowest_heap_address = ~(mword)0;
398 static mword highest_heap_address = 0;
400 LOCK_DECLARE (sgen_interruption_mutex);
401 static LOCK_DECLARE (pin_queue_mutex);
403 #define LOCK_PIN_QUEUE mono_mutex_lock (&pin_queue_mutex)
404 #define UNLOCK_PIN_QUEUE mono_mutex_unlock (&pin_queue_mutex)
406 typedef struct _FinalizeReadyEntry FinalizeReadyEntry;
407 struct _FinalizeReadyEntry {
408 FinalizeReadyEntry *next;
412 typedef struct _EphemeronLinkNode EphemeronLinkNode;
414 struct _EphemeronLinkNode {
415 EphemeronLinkNode *next;
424 int current_collection_generation = -1;
426 /* objects that are ready to be finalized */
427 static FinalizeReadyEntry *fin_ready_list = NULL;
428 static FinalizeReadyEntry *critical_fin_list = NULL;
430 static EphemeronLinkNode *ephemeron_list;
432 /* registered roots: the key to the hash is the root start address */
434 * Different kinds of roots are kept separate to speed up pin_from_roots () for example.
436 SgenHashTable roots_hash [ROOT_TYPE_NUM] = {
437 SGEN_HASH_TABLE_INIT (INTERNAL_MEM_ROOTS_TABLE, INTERNAL_MEM_ROOT_RECORD, sizeof (RootRecord), mono_aligned_addr_hash, NULL),
438 SGEN_HASH_TABLE_INIT (INTERNAL_MEM_ROOTS_TABLE, INTERNAL_MEM_ROOT_RECORD, sizeof (RootRecord), mono_aligned_addr_hash, NULL),
439 SGEN_HASH_TABLE_INIT (INTERNAL_MEM_ROOTS_TABLE, INTERNAL_MEM_ROOT_RECORD, sizeof (RootRecord), mono_aligned_addr_hash, NULL)
441 static mword roots_size = 0; /* amount of memory in the root set */
443 #define GC_ROOT_NUM 32
446 void *objects [GC_ROOT_NUM];
447 int root_types [GC_ROOT_NUM];
448 uintptr_t extra_info [GC_ROOT_NUM];
452 notify_gc_roots (GCRootReport *report)
456 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
461 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
463 if (report->count == GC_ROOT_NUM)
464 notify_gc_roots (report);
465 report->objects [report->count] = object;
466 report->root_types [report->count] = rtype;
467 report->extra_info [report->count++] = (uintptr_t)((MonoVTable*)LOAD_VTABLE (object))->klass;
470 MonoNativeTlsKey thread_info_key;
472 #ifdef HAVE_KW_THREAD
473 __thread SgenThreadInfo *sgen_thread_info;
474 __thread gpointer *store_remset_buffer;
475 __thread long store_remset_buffer_index;
476 __thread char *stack_end;
477 __thread long *store_remset_buffer_index_addr;
480 /* The size of a TLAB */
481 /* The bigger the value, the less often we have to go to the slow path to allocate a new
482 * one, but the more space is wasted by threads not allocating much memory.
484 * FIXME: Make this self-tuning for each thread.
486 guint32 tlab_size = (1024 * 4);
488 #define MAX_SMALL_OBJ_SIZE SGEN_MAX_SMALL_OBJ_SIZE
490 /* Functions supplied by the runtime to be called by the GC */
491 static MonoGCCallbacks gc_callbacks;
493 #define ALLOC_ALIGN SGEN_ALLOC_ALIGN
494 #define ALLOC_ALIGN_BITS SGEN_ALLOC_ALIGN_BITS
496 #define ALIGN_UP SGEN_ALIGN_UP
498 #define MOVED_OBJECTS_NUM 64
499 static void *moved_objects [MOVED_OBJECTS_NUM];
500 static int moved_objects_idx = 0;
502 /* Vtable of the objects used to fill out nursery fragments before a collection */
503 static MonoVTable *array_fill_vtable;
505 #ifdef SGEN_DEBUG_INTERNAL_ALLOC
506 MonoNativeThreadId main_gc_thread = NULL;
509 /*Object was pinned during the current collection*/
510 static mword objects_pinned;
513 * ######################################################################
514 * ######## Macros and function declarations.
515 * ######################################################################
519 align_pointer (void *ptr)
521 mword p = (mword)ptr;
522 p += sizeof (gpointer) - 1;
523 p &= ~ (sizeof (gpointer) - 1);
527 typedef SgenGrayQueue GrayQueue;
529 /* forward declarations */
530 static void scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, GrayQueue *queue);
531 static void scan_from_registered_roots (CopyOrMarkObjectFunc copy_func, char *addr_start, char *addr_end, int root_type, GrayQueue *queue);
532 static void scan_finalizer_entries (CopyOrMarkObjectFunc copy_func, FinalizeReadyEntry *list, GrayQueue *queue);
533 static void report_finalizer_roots (void);
534 static void report_registered_roots (void);
536 static void pin_from_roots (void *start_nursery, void *end_nursery, GrayQueue *queue);
537 static int pin_objects_from_addresses (GCMemSection *section, void **start, void **end, void *start_nursery, void *end_nursery, GrayQueue *queue);
538 static void finish_gray_stack (char *start_addr, char *end_addr, int generation, GrayQueue *queue);
540 void mono_gc_scan_for_specific_ref (MonoObject *key, gboolean precise);
543 static void init_stats (void);
545 static int mark_ephemerons_in_range (CopyOrMarkObjectFunc copy_func, char *start, char *end, GrayQueue *queue);
546 static void clear_unreachable_ephemerons (CopyOrMarkObjectFunc copy_func, char *start, char *end, GrayQueue *queue);
547 static void null_ephemerons_for_domain (MonoDomain *domain);
549 SgenObjectOperations current_object_ops;
550 SgenMajorCollector major_collector;
551 SgenMinorCollector sgen_minor_collector;
552 static GrayQueue gray_queue;
554 static SgenRemeberedSet remset;
557 #define WORKERS_DISTRIBUTE_GRAY_QUEUE (sgen_collection_is_parallel () ? sgen_workers_get_distribute_gray_queue () : &gray_queue)
559 static SgenGrayQueue*
560 sgen_workers_get_job_gray_queue (WorkerData *worker_data)
562 return worker_data ? &worker_data->private_gray_queue : WORKERS_DISTRIBUTE_GRAY_QUEUE;
566 is_xdomain_ref_allowed (gpointer *ptr, char *obj, MonoDomain *domain)
568 MonoObject *o = (MonoObject*)(obj);
569 MonoObject *ref = (MonoObject*)*(ptr);
570 int offset = (char*)(ptr) - (char*)o;
572 if (o->vtable->klass == mono_defaults.thread_class && offset == G_STRUCT_OFFSET (MonoThread, internal_thread))
574 if (o->vtable->klass == mono_defaults.internal_thread_class && offset == G_STRUCT_OFFSET (MonoInternalThread, current_appcontext))
576 if (mono_class_has_parent_fast (o->vtable->klass, mono_defaults.real_proxy_class) &&
577 offset == G_STRUCT_OFFSET (MonoRealProxy, unwrapped_server))
579 /* Thread.cached_culture_info */
580 if (!strcmp (ref->vtable->klass->name_space, "System.Globalization") &&
581 !strcmp (ref->vtable->klass->name, "CultureInfo") &&
582 !strcmp(o->vtable->klass->name_space, "System") &&
583 !strcmp(o->vtable->klass->name, "Object[]"))
586 * at System.IO.MemoryStream.InternalConstructor (byte[],int,int,bool,bool) [0x0004d] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.IO/MemoryStream.cs:121
587 * at System.IO.MemoryStream..ctor (byte[]) [0x00017] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.IO/MemoryStream.cs:81
588 * at (wrapper remoting-invoke-with-check) System.IO.MemoryStream..ctor (byte[]) <IL 0x00020, 0xffffffff>
589 * at System.Runtime.Remoting.Messaging.CADMethodCallMessage.GetArguments () [0x0000d] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.Runtime.Remoting.Messaging/CADMessages.cs:327
590 * at System.Runtime.Remoting.Messaging.MethodCall..ctor (System.Runtime.Remoting.Messaging.CADMethodCallMessage) [0x00017] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.Runtime.Remoting.Messaging/MethodCall.cs:87
591 * at System.AppDomain.ProcessMessageInDomain (byte[],System.Runtime.Remoting.Messaging.CADMethodCallMessage,byte[]&,System.Runtime.Remoting.Messaging.CADMethodReturnMessage&) [0x00018] in /home/schani/Work/novell/trunk/mcs/class/corlib/System/AppDomain.cs:1213
592 * at (wrapper remoting-invoke-with-check) System.AppDomain.ProcessMessageInDomain (byte[],System.Runtime.Remoting.Messaging.CADMethodCallMessage,byte[]&,System.Runtime.Remoting.Messaging.CADMethodReturnMessage&) <IL 0x0003d, 0xffffffff>
593 * at System.Runtime.Remoting.Channels.CrossAppDomainSink.ProcessMessageInDomain (byte[],System.Runtime.Remoting.Messaging.CADMethodCallMessage) [0x00008] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.Runtime.Remoting.Channels/CrossAppDomainChannel.cs:198
594 * at (wrapper runtime-invoke) object.runtime_invoke_CrossAppDomainSink/ProcessMessageRes_object_object (object,intptr,intptr,intptr) <IL 0x0004c, 0xffffffff>
596 if (!strcmp (ref->vtable->klass->name_space, "System") &&
597 !strcmp (ref->vtable->klass->name, "Byte[]") &&
598 !strcmp (o->vtable->klass->name_space, "System.IO") &&
599 !strcmp (o->vtable->klass->name, "MemoryStream"))
601 /* append_job() in threadpool.c */
602 if (!strcmp (ref->vtable->klass->name_space, "System.Runtime.Remoting.Messaging") &&
603 !strcmp (ref->vtable->klass->name, "AsyncResult") &&
604 !strcmp (o->vtable->klass->name_space, "System") &&
605 !strcmp (o->vtable->klass->name, "Object[]") &&
606 mono_thread_pool_is_queue_array ((MonoArray*) o))
612 check_reference_for_xdomain (gpointer *ptr, char *obj, MonoDomain *domain)
614 MonoObject *o = (MonoObject*)(obj);
615 MonoObject *ref = (MonoObject*)*(ptr);
616 int offset = (char*)(ptr) - (char*)o;
618 MonoClassField *field;
621 if (!ref || ref->vtable->domain == domain)
623 if (is_xdomain_ref_allowed (ptr, obj, domain))
627 for (class = o->vtable->klass; class; class = class->parent) {
630 for (i = 0; i < class->field.count; ++i) {
631 if (class->fields[i].offset == offset) {
632 field = &class->fields[i];
640 if (ref->vtable->klass == mono_defaults.string_class)
641 str = mono_string_to_utf8 ((MonoString*)ref);
644 g_print ("xdomain reference in %p (%s.%s) at offset %d (%s) to %p (%s.%s) (%s) - pointed to by:\n",
645 o, o->vtable->klass->name_space, o->vtable->klass->name,
646 offset, field ? field->name : "",
647 ref, ref->vtable->klass->name_space, ref->vtable->klass->name, str ? str : "");
648 mono_gc_scan_for_specific_ref (o, TRUE);
654 #define HANDLE_PTR(ptr,obj) check_reference_for_xdomain ((ptr), (obj), domain)
657 scan_object_for_xdomain_refs (char *start, mword size, void *data)
659 MonoDomain *domain = ((MonoObject*)start)->vtable->domain;
661 #include "sgen-scan-object.h"
664 static gboolean scan_object_for_specific_ref_precise = TRUE;
667 #define HANDLE_PTR(ptr,obj) do { \
668 if ((MonoObject*)*(ptr) == key) { \
669 g_print ("found ref to %p in object %p (%s) at offset %td\n", \
670 key, (obj), safe_name ((obj)), ((char*)(ptr) - (char*)(obj))); \
675 scan_object_for_specific_ref (char *start, MonoObject *key)
679 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (start)))
682 if (scan_object_for_specific_ref_precise) {
683 #include "sgen-scan-object.h"
685 mword *words = (mword*)start;
686 size_t size = safe_object_get_size ((MonoObject*)start);
688 for (i = 0; i < size / sizeof (mword); ++i) {
689 if (words [i] == (mword)key) {
690 g_print ("found possible ref to %p in object %p (%s) at offset %td\n",
691 key, start, safe_name (start), i * sizeof (mword));
698 sgen_scan_area_with_callback (char *start, char *end, IterateObjectCallbackFunc callback, void *data, gboolean allow_flags)
700 while (start < end) {
704 if (!*(void**)start) {
705 start += sizeof (void*); /* should be ALLOC_ALIGN, really */
710 if (!(obj = SGEN_OBJECT_IS_FORWARDED (start)))
716 size = ALIGN_UP (safe_object_get_size ((MonoObject*)obj));
718 if ((MonoVTable*)SGEN_LOAD_VTABLE (obj) != array_fill_vtable)
719 callback (obj, size, data);
726 scan_object_for_specific_ref_callback (char *obj, size_t size, MonoObject *key)
728 scan_object_for_specific_ref (obj, key);
732 check_root_obj_specific_ref (RootRecord *root, MonoObject *key, MonoObject *obj)
736 g_print ("found ref to %p in root record %p\n", key, root);
739 static MonoObject *check_key = NULL;
740 static RootRecord *check_root = NULL;
743 check_root_obj_specific_ref_from_marker (void **obj)
745 check_root_obj_specific_ref (check_root, check_key, *obj);
749 scan_roots_for_specific_ref (MonoObject *key, int root_type)
755 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], start_root, root) {
756 mword desc = root->root_desc;
760 switch (desc & ROOT_DESC_TYPE_MASK) {
761 case ROOT_DESC_BITMAP:
762 desc >>= ROOT_DESC_TYPE_SHIFT;
765 check_root_obj_specific_ref (root, key, *start_root);
770 case ROOT_DESC_COMPLEX: {
771 gsize *bitmap_data = sgen_get_complex_descriptor_bitmap (desc);
772 int bwords = (*bitmap_data) - 1;
773 void **start_run = start_root;
775 while (bwords-- > 0) {
776 gsize bmap = *bitmap_data++;
777 void **objptr = start_run;
780 check_root_obj_specific_ref (root, key, *objptr);
784 start_run += GC_BITS_PER_WORD;
788 case ROOT_DESC_USER: {
789 MonoGCRootMarkFunc marker = sgen_get_user_descriptor_func (desc);
790 marker (start_root, check_root_obj_specific_ref_from_marker);
793 case ROOT_DESC_RUN_LEN:
794 g_assert_not_reached ();
796 g_assert_not_reached ();
798 } SGEN_HASH_TABLE_FOREACH_END;
805 mono_gc_scan_for_specific_ref (MonoObject *key, gboolean precise)
810 scan_object_for_specific_ref_precise = precise;
812 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
813 (IterateObjectCallbackFunc)scan_object_for_specific_ref_callback, key, TRUE);
815 major_collector.iterate_objects (TRUE, TRUE, (IterateObjectCallbackFunc)scan_object_for_specific_ref_callback, key);
817 sgen_los_iterate_objects ((IterateObjectCallbackFunc)scan_object_for_specific_ref_callback, key);
819 scan_roots_for_specific_ref (key, ROOT_TYPE_NORMAL);
820 scan_roots_for_specific_ref (key, ROOT_TYPE_WBARRIER);
822 SGEN_HASH_TABLE_FOREACH (&roots_hash [ROOT_TYPE_PINNED], ptr, root) {
823 while (ptr < (void**)root->end_root) {
824 check_root_obj_specific_ref (root, *ptr, key);
827 } SGEN_HASH_TABLE_FOREACH_END;
831 need_remove_object_for_domain (char *start, MonoDomain *domain)
833 if (mono_object_domain (start) == domain) {
834 SGEN_LOG (4, "Need to cleanup object %p", start);
835 binary_protocol_cleanup (start, (gpointer)LOAD_VTABLE (start), safe_object_get_size ((MonoObject*)start));
842 process_object_for_domain_clearing (char *start, MonoDomain *domain)
844 GCVTable *vt = (GCVTable*)LOAD_VTABLE (start);
845 if (vt->klass == mono_defaults.internal_thread_class)
846 g_assert (mono_object_domain (start) == mono_get_root_domain ());
847 /* The object could be a proxy for an object in the domain
849 if (mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
850 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
852 /* The server could already have been zeroed out, so
853 we need to check for that, too. */
854 if (server && (!LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
855 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
856 ((MonoRealProxy*)start)->unwrapped_server = NULL;
861 static MonoDomain *check_domain = NULL;
864 check_obj_not_in_domain (void **o)
866 g_assert (((MonoObject*)(*o))->vtable->domain != check_domain);
870 scan_for_registered_roots_in_domain (MonoDomain *domain, int root_type)
874 check_domain = domain;
875 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], start_root, root) {
876 mword desc = root->root_desc;
878 /* The MonoDomain struct is allowed to hold
879 references to objects in its own domain. */
880 if (start_root == (void**)domain)
883 switch (desc & ROOT_DESC_TYPE_MASK) {
884 case ROOT_DESC_BITMAP:
885 desc >>= ROOT_DESC_TYPE_SHIFT;
887 if ((desc & 1) && *start_root)
888 check_obj_not_in_domain (*start_root);
893 case ROOT_DESC_COMPLEX: {
894 gsize *bitmap_data = sgen_get_complex_descriptor_bitmap (desc);
895 int bwords = (*bitmap_data) - 1;
896 void **start_run = start_root;
898 while (bwords-- > 0) {
899 gsize bmap = *bitmap_data++;
900 void **objptr = start_run;
902 if ((bmap & 1) && *objptr)
903 check_obj_not_in_domain (*objptr);
907 start_run += GC_BITS_PER_WORD;
911 case ROOT_DESC_USER: {
912 MonoGCRootMarkFunc marker = sgen_get_user_descriptor_func (desc);
913 marker (start_root, check_obj_not_in_domain);
916 case ROOT_DESC_RUN_LEN:
917 g_assert_not_reached ();
919 g_assert_not_reached ();
921 } SGEN_HASH_TABLE_FOREACH_END;
927 check_for_xdomain_refs (void)
931 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
932 (IterateObjectCallbackFunc)scan_object_for_xdomain_refs, NULL, FALSE);
934 major_collector.iterate_objects (TRUE, TRUE, (IterateObjectCallbackFunc)scan_object_for_xdomain_refs, NULL);
936 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
937 scan_object_for_xdomain_refs (bigobj->data, bigobj->size, NULL);
941 clear_domain_process_object (char *obj, MonoDomain *domain)
945 process_object_for_domain_clearing (obj, domain);
946 remove = need_remove_object_for_domain (obj, domain);
948 if (remove && ((MonoObject*)obj)->synchronisation) {
949 void **dislink = mono_monitor_get_object_monitor_weak_link ((MonoObject*)obj);
951 sgen_register_disappearing_link (NULL, dislink, FALSE, TRUE);
958 clear_domain_process_minor_object_callback (char *obj, size_t size, MonoDomain *domain)
960 if (clear_domain_process_object (obj, domain))
961 memset (obj, 0, size);
965 clear_domain_process_major_object_callback (char *obj, size_t size, MonoDomain *domain)
967 clear_domain_process_object (obj, domain);
971 clear_domain_free_major_non_pinned_object_callback (char *obj, size_t size, MonoDomain *domain)
973 if (need_remove_object_for_domain (obj, domain))
974 major_collector.free_non_pinned_object (obj, size);
978 clear_domain_free_major_pinned_object_callback (char *obj, size_t size, MonoDomain *domain)
980 if (need_remove_object_for_domain (obj, domain))
981 major_collector.free_pinned_object (obj, size);
985 * When appdomains are unloaded we can easily remove objects that have finalizers,
986 * but all the others could still be present in random places on the heap.
987 * We need a sweep to get rid of them even though it's going to be costly
989 * The reason we need to remove them is because we access the vtable and class
990 * structures to know the object size and the reference bitmap: once the domain is
991 * unloaded the point to random memory.
994 mono_gc_clear_domain (MonoDomain * domain)
996 LOSObject *bigobj, *prev;
1001 sgen_process_fin_stage_entries ();
1002 sgen_process_dislink_stage_entries ();
1004 sgen_clear_nursery_fragments ();
1006 if (xdomain_checks && domain != mono_get_root_domain ()) {
1007 scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
1008 scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
1009 check_for_xdomain_refs ();
1012 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
1013 to memory returned to the OS.*/
1014 null_ephemerons_for_domain (domain);
1016 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
1017 sgen_null_links_for_domain (domain, i);
1019 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
1020 sgen_remove_finalizers_for_domain (domain, i);
1022 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
1023 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE);
1025 /* We need two passes over major and large objects because
1026 freeing such objects might give their memory back to the OS
1027 (in the case of large objects) or obliterate its vtable
1028 (pinned objects with major-copying or pinned and non-pinned
1029 objects with major-mark&sweep), but we might need to
1030 dereference a pointer from an object to another object if
1031 the first object is a proxy. */
1032 major_collector.iterate_objects (TRUE, TRUE, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
1033 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
1034 clear_domain_process_object (bigobj->data, domain);
1037 for (bigobj = los_object_list; bigobj;) {
1038 if (need_remove_object_for_domain (bigobj->data, domain)) {
1039 LOSObject *to_free = bigobj;
1041 prev->next = bigobj->next;
1043 los_object_list = bigobj->next;
1044 bigobj = bigobj->next;
1045 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
1046 sgen_los_free_object (to_free);
1050 bigobj = bigobj->next;
1052 major_collector.iterate_objects (TRUE, FALSE, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
1053 major_collector.iterate_objects (FALSE, TRUE, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
1055 if (G_UNLIKELY (do_pin_stats)) {
1056 if (domain == mono_get_root_domain ())
1057 sgen_pin_stats_print_class_stats ();
1064 * sgen_add_to_global_remset:
1066 * The global remset contains locations which point into newspace after
1067 * a minor collection. This can happen if the objects they point to are pinned.
1069 * LOCKING: If called from a parallel collector, the global remset
1070 * lock must be held. For serial collectors that is not necessary.
1073 sgen_add_to_global_remset (gpointer ptr)
1075 remset.record_pointer (ptr);
1079 * sgen_drain_gray_stack:
1081 * Scan objects in the gray stack until the stack is empty. This should be called
1082 * frequently after each object is copied, to achieve better locality and cache
1086 sgen_drain_gray_stack (GrayQueue *queue, int max_objs)
1089 ScanObjectFunc scan_func = current_object_ops.scan_object;
1091 if (max_objs == -1) {
1093 GRAY_OBJECT_DEQUEUE (queue, obj);
1096 SGEN_LOG (9, "Precise gray object scan %p (%s)", obj, safe_name (obj));
1097 scan_func (obj, queue);
1103 for (i = 0; i != max_objs; ++i) {
1104 GRAY_OBJECT_DEQUEUE (queue, obj);
1107 SGEN_LOG (9, "Precise gray object scan %p (%s)", obj, safe_name (obj));
1108 scan_func (obj, queue);
1110 } while (max_objs < 0);
1116 * Addresses from start to end are already sorted. This function finds
1117 * the object header for each address and pins the object. The
1118 * addresses must be inside the passed section. The (start of the)
1119 * address array is overwritten with the addresses of the actually
1120 * pinned objects. Return the number of pinned objects.
1123 pin_objects_from_addresses (GCMemSection *section, void **start, void **end, void *start_nursery, void *end_nursery, GrayQueue *queue)
1128 void *last_obj = NULL;
1129 size_t last_obj_size = 0;
1132 void **definitely_pinned = start;
1134 sgen_nursery_allocator_prepare_for_pinning ();
1136 while (start < end) {
1138 /* the range check should be reduntant */
1139 if (addr != last && addr >= start_nursery && addr < end_nursery) {
1140 SGEN_LOG (5, "Considering pinning addr %p", addr);
1141 /* multiple pointers to the same object */
1142 if (addr >= last_obj && (char*)addr < (char*)last_obj + last_obj_size) {
1146 idx = ((char*)addr - (char*)section->data) / SCAN_START_SIZE;
1147 g_assert (idx < section->num_scan_start);
1148 search_start = (void*)section->scan_starts [idx];
1149 if (!search_start || search_start > addr) {
1152 search_start = section->scan_starts [idx];
1153 if (search_start && search_start <= addr)
1156 if (!search_start || search_start > addr)
1157 search_start = start_nursery;
1159 if (search_start < last_obj)
1160 search_start = (char*)last_obj + last_obj_size;
1161 /* now addr should be in an object a short distance from search_start
1162 * Note that search_start must point to zeroed mem or point to an object.
1166 if (!*(void**)search_start) {
1167 /* Consistency check */
1169 for (frag = nursery_fragments; frag; frag = frag->next) {
1170 if (search_start >= frag->fragment_start && search_start < frag->fragment_end)
1171 g_assert_not_reached ();
1175 search_start = (void*)ALIGN_UP ((mword)search_start + sizeof (gpointer));
1178 last_obj = search_start;
1179 last_obj_size = ALIGN_UP (safe_object_get_size ((MonoObject*)search_start));
1181 if (((MonoObject*)last_obj)->synchronisation == GINT_TO_POINTER (-1)) {
1182 /* Marks the beginning of a nursery fragment, skip */
1184 SGEN_LOG (8, "Pinned try match %p (%s), size %zd", last_obj, safe_name (last_obj), last_obj_size);
1185 if (addr >= search_start && (char*)addr < (char*)last_obj + last_obj_size) {
1186 SGEN_LOG (4, "Pinned object %p, vtable %p (%s), count %d\n", search_start, *(void**)search_start, safe_name (search_start), count);
1187 binary_protocol_pin (search_start, (gpointer)LOAD_VTABLE (search_start), safe_object_get_size (search_start));
1188 if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1189 int gen = sgen_ptr_in_nursery (search_start) ? GENERATION_NURSERY : GENERATION_OLD;
1190 MonoVTable *vt = (MonoVTable*)LOAD_VTABLE (search_start);
1191 MONO_GC_OBJ_PINNED ((mword)search_start, sgen_safe_object_get_size (search_start), vt->klass->name_space, vt->klass->name, gen);
1193 pin_object (search_start);
1194 GRAY_OBJECT_ENQUEUE (queue, search_start);
1195 if (G_UNLIKELY (do_pin_stats))
1196 sgen_pin_stats_register_object (search_start, last_obj_size);
1197 definitely_pinned [count] = search_start;
1202 /* skip to the next object */
1203 search_start = (void*)((char*)search_start + last_obj_size);
1204 } while (search_start <= addr);
1205 /* we either pinned the correct object or we ignored the addr because
1206 * it points to unused zeroed memory.
1212 //printf ("effective pinned: %d (at the end: %d)\n", count, (char*)end_nursery - (char*)last);
1213 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1214 GCRootReport report;
1216 for (idx = 0; idx < count; ++idx)
1217 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1218 notify_gc_roots (&report);
1220 stat_pinned_objects += count;
1225 sgen_pin_objects_in_section (GCMemSection *section, GrayQueue *queue)
1227 int num_entries = section->pin_queue_num_entries;
1229 void **start = section->pin_queue_start;
1231 reduced_to = pin_objects_from_addresses (section, start, start + num_entries,
1232 section->data, section->next_data, queue);
1233 section->pin_queue_num_entries = reduced_to;
1235 section->pin_queue_start = NULL;
1241 sgen_pin_object (void *object, GrayQueue *queue)
1243 if (sgen_collection_is_parallel ()) {
1245 /*object arrives pinned*/
1246 sgen_pin_stage_ptr (object);
1250 SGEN_PIN_OBJECT (object);
1251 sgen_pin_stage_ptr (object);
1253 if (G_UNLIKELY (do_pin_stats))
1254 sgen_pin_stats_register_object (object, safe_object_get_size (object));
1256 GRAY_OBJECT_ENQUEUE (queue, object);
1257 binary_protocol_pin (object, (gpointer)LOAD_VTABLE (object), safe_object_get_size (object));
1258 if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
1259 int gen = sgen_ptr_in_nursery (object) ? GENERATION_NURSERY : GENERATION_OLD;
1260 MonoVTable *vt = (MonoVTable*)LOAD_VTABLE (object);
1261 MONO_GC_OBJ_PINNED ((mword)object, sgen_safe_object_get_size (object), vt->klass->name_space, vt->klass->name, gen);
1266 sgen_parallel_pin_or_update (void **ptr, void *obj, MonoVTable *vt, SgenGrayQueue *queue)
1270 gboolean major_pinned = FALSE;
1272 if (sgen_ptr_in_nursery (obj)) {
1273 if (SGEN_CAS_PTR (obj, (void*)((mword)vt | SGEN_PINNED_BIT), vt) == vt) {
1274 sgen_pin_object (obj, queue);
1278 major_collector.pin_major_object (obj, queue);
1279 major_pinned = TRUE;
1282 vtable_word = *(mword*)obj;
1283 /*someone else forwarded it, update the pointer and bail out*/
1284 if (vtable_word & SGEN_FORWARDED_BIT) {
1285 *ptr = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
1289 /*someone pinned it, nothing to do.*/
1290 if (vtable_word & SGEN_PINNED_BIT || major_pinned)
1295 /* Sort the addresses in array in increasing order.
1296 * Done using a by-the book heap sort. Which has decent and stable performance, is pretty cache efficient.
1299 sgen_sort_addresses (void **array, int size)
1304 for (i = 1; i < size; ++i) {
1307 int parent = (child - 1) / 2;
1309 if (array [parent] >= array [child])
1312 tmp = array [parent];
1313 array [parent] = array [child];
1314 array [child] = tmp;
1320 for (i = size - 1; i > 0; --i) {
1323 array [i] = array [0];
1329 while (root * 2 + 1 <= end) {
1330 int child = root * 2 + 1;
1332 if (child < end && array [child] < array [child + 1])
1334 if (array [root] >= array [child])
1338 array [root] = array [child];
1339 array [child] = tmp;
1347 * Scan the memory between start and end and queue values which could be pointers
1348 * to the area between start_nursery and end_nursery for later consideration.
1349 * Typically used for thread stacks.
1352 conservatively_pin_objects_from (void **start, void **end, void *start_nursery, void *end_nursery, int pin_type)
1356 #ifdef VALGRIND_MAKE_MEM_DEFINED_IF_ADDRESSABLE
1357 VALGRIND_MAKE_MEM_DEFINED_IF_ADDRESSABLE (start, (char*)end - (char*)start);
1360 while (start < end) {
1361 if (*start >= start_nursery && *start < end_nursery) {
1363 * *start can point to the middle of an object
1364 * note: should we handle pointing at the end of an object?
1365 * pinning in C# code disallows pointing at the end of an object
1366 * but there is some small chance that an optimizing C compiler
1367 * may keep the only reference to an object by pointing
1368 * at the end of it. We ignore this small chance for now.
1369 * Pointers to the end of an object are indistinguishable
1370 * from pointers to the start of the next object in memory
1371 * so if we allow that we'd need to pin two objects...
1372 * We queue the pointer in an array, the
1373 * array will then be sorted and uniqued. This way
1374 * we can coalesce several pinning pointers and it should
1375 * be faster since we'd do a memory scan with increasing
1376 * addresses. Note: we can align the address to the allocation
1377 * alignment, so the unique process is more effective.
1379 mword addr = (mword)*start;
1380 addr &= ~(ALLOC_ALIGN - 1);
1381 if (addr >= (mword)start_nursery && addr < (mword)end_nursery) {
1382 SGEN_LOG (6, "Pinning address %p from %p", (void*)addr, start);
1383 sgen_pin_stage_ptr ((void*)addr);
1386 if (G_UNLIKELY (do_pin_stats)) {
1387 if (ptr_in_nursery ((void*)addr))
1388 sgen_pin_stats_register_address ((char*)addr, pin_type);
1394 SGEN_LOG (7, "found %d potential pinned heap pointers", count);
1398 * The first thing we do in a collection is to identify pinned objects.
1399 * This function considers all the areas of memory that need to be
1400 * conservatively scanned.
1403 pin_from_roots (void *start_nursery, void *end_nursery, GrayQueue *queue)
1407 SGEN_LOG (2, "Scanning pinned roots (%d bytes, %d/%d entries)", (int)roots_size, roots_hash [ROOT_TYPE_NORMAL].num_entries, roots_hash [ROOT_TYPE_PINNED].num_entries);
1408 /* objects pinned from the API are inside these roots */
1409 SGEN_HASH_TABLE_FOREACH (&roots_hash [ROOT_TYPE_PINNED], start_root, root) {
1410 SGEN_LOG (6, "Pinned roots %p-%p", start_root, root->end_root);
1411 conservatively_pin_objects_from (start_root, (void**)root->end_root, start_nursery, end_nursery, PIN_TYPE_OTHER);
1412 } SGEN_HASH_TABLE_FOREACH_END;
1413 /* now deal with the thread stacks
1414 * in the future we should be able to conservatively scan only:
1415 * *) the cpu registers
1416 * *) the unmanaged stack frames
1417 * *) the _last_ managed stack frame
1418 * *) pointers slots in managed frames
1420 scan_thread_data (start_nursery, end_nursery, FALSE, queue);
1424 CopyOrMarkObjectFunc func;
1426 } UserCopyOrMarkData;
1428 static MonoNativeTlsKey user_copy_or_mark_key;
1431 init_user_copy_or_mark_key (void)
1433 mono_native_tls_alloc (&user_copy_or_mark_key, NULL);
1437 set_user_copy_or_mark_data (UserCopyOrMarkData *data)
1439 mono_native_tls_set_value (user_copy_or_mark_key, data);
1443 single_arg_user_copy_or_mark (void **obj)
1445 UserCopyOrMarkData *data = mono_native_tls_get_value (user_copy_or_mark_key);
1447 data->func (obj, data->queue);
1451 * The memory area from start_root to end_root contains pointers to objects.
1452 * Their position is precisely described by @desc (this means that the pointer
1453 * can be either NULL or the pointer to the start of an object).
1454 * This functions copies them to to_space updates them.
1456 * This function is not thread-safe!
1459 precisely_scan_objects_from (CopyOrMarkObjectFunc copy_func, void** start_root, void** end_root, char* n_start, char *n_end, mword desc, GrayQueue *queue)
1461 switch (desc & ROOT_DESC_TYPE_MASK) {
1462 case ROOT_DESC_BITMAP:
1463 desc >>= ROOT_DESC_TYPE_SHIFT;
1465 if ((desc & 1) && *start_root) {
1466 copy_func (start_root, queue);
1467 SGEN_LOG (9, "Overwrote root at %p with %p", start_root, *start_root);
1468 sgen_drain_gray_stack (queue, -1);
1474 case ROOT_DESC_COMPLEX: {
1475 gsize *bitmap_data = sgen_get_complex_descriptor_bitmap (desc);
1476 int bwords = (*bitmap_data) - 1;
1477 void **start_run = start_root;
1479 while (bwords-- > 0) {
1480 gsize bmap = *bitmap_data++;
1481 void **objptr = start_run;
1483 if ((bmap & 1) && *objptr) {
1484 copy_func (objptr, queue);
1485 SGEN_LOG (9, "Overwrote root at %p with %p", objptr, *objptr);
1486 sgen_drain_gray_stack (queue, -1);
1491 start_run += GC_BITS_PER_WORD;
1495 case ROOT_DESC_USER: {
1496 UserCopyOrMarkData data = { copy_func, queue };
1497 MonoGCRootMarkFunc marker = sgen_get_user_descriptor_func (desc);
1498 set_user_copy_or_mark_data (&data);
1499 marker (start_root, single_arg_user_copy_or_mark);
1500 set_user_copy_or_mark_data (NULL);
1503 case ROOT_DESC_RUN_LEN:
1504 g_assert_not_reached ();
1506 g_assert_not_reached ();
1511 reset_heap_boundaries (void)
1513 lowest_heap_address = ~(mword)0;
1514 highest_heap_address = 0;
1518 sgen_update_heap_boundaries (mword low, mword high)
1523 old = lowest_heap_address;
1526 } while (SGEN_CAS_PTR ((gpointer*)&lowest_heap_address, (gpointer)low, (gpointer)old) != (gpointer)old);
1529 old = highest_heap_address;
1532 } while (SGEN_CAS_PTR ((gpointer*)&highest_heap_address, (gpointer)high, (gpointer)old) != (gpointer)old);
1536 * Allocate and setup the data structures needed to be able to allocate objects
1537 * in the nursery. The nursery is stored in nursery_section.
1540 alloc_nursery (void)
1542 GCMemSection *section;
1547 if (nursery_section)
1549 SGEN_LOG (2, "Allocating nursery size: %lu", (unsigned long)sgen_nursery_size);
1550 /* later we will alloc a larger area for the nursery but only activate
1551 * what we need. The rest will be used as expansion if we have too many pinned
1552 * objects in the existing nursery.
1554 /* FIXME: handle OOM */
1555 section = sgen_alloc_internal (INTERNAL_MEM_SECTION);
1557 alloc_size = sgen_nursery_size;
1559 /* If there isn't enough space even for the nursery we should simply abort. */
1560 g_assert (sgen_memgov_try_alloc_space (alloc_size, SPACE_NURSERY));
1562 #ifdef SGEN_ALIGN_NURSERY
1563 data = major_collector.alloc_heap (alloc_size, alloc_size, DEFAULT_NURSERY_BITS);
1565 data = major_collector.alloc_heap (alloc_size, 0, DEFAULT_NURSERY_BITS);
1567 sgen_update_heap_boundaries ((mword)data, (mword)(data + sgen_nursery_size));
1568 SGEN_LOG (4, "Expanding nursery size (%p-%p): %lu, total: %lu", data, data + alloc_size, (unsigned long)sgen_nursery_size, (unsigned long)mono_gc_get_heap_size ());
1569 section->data = section->next_data = data;
1570 section->size = alloc_size;
1571 section->end_data = data + sgen_nursery_size;
1572 scan_starts = (alloc_size + SCAN_START_SIZE - 1) / SCAN_START_SIZE;
1573 section->scan_starts = sgen_alloc_internal_dynamic (sizeof (char*) * scan_starts, INTERNAL_MEM_SCAN_STARTS, TRUE);
1574 section->num_scan_start = scan_starts;
1575 section->block.role = MEMORY_ROLE_GEN0;
1576 section->block.next = NULL;
1578 nursery_section = section;
1580 sgen_nursery_allocator_set_nursery_bounds (data, data + sgen_nursery_size);
1584 mono_gc_get_nursery (int *shift_bits, size_t *size)
1586 *size = sgen_nursery_size;
1587 #ifdef SGEN_ALIGN_NURSERY
1588 *shift_bits = DEFAULT_NURSERY_BITS;
1592 return sgen_get_nursery_start ();
1596 mono_gc_set_current_thread_appdomain (MonoDomain *domain)
1598 SgenThreadInfo *info = mono_thread_info_current ();
1600 /* Could be called from sgen_thread_unregister () with a NULL info */
1603 info->stopped_domain = domain;
1608 mono_gc_precise_stack_mark_enabled (void)
1610 return !conservative_stack_mark;
1614 mono_gc_get_logfile (void)
1616 return gc_debug_file;
1620 report_finalizer_roots_list (FinalizeReadyEntry *list)
1622 GCRootReport report;
1623 FinalizeReadyEntry *fin;
1626 for (fin = list; fin; fin = fin->next) {
1629 add_profile_gc_root (&report, fin->object, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1631 notify_gc_roots (&report);
1635 report_finalizer_roots (void)
1637 report_finalizer_roots_list (fin_ready_list);
1638 report_finalizer_roots_list (critical_fin_list);
1641 static GCRootReport *root_report;
1644 single_arg_report_root (void **obj)
1647 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1651 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1653 switch (desc & ROOT_DESC_TYPE_MASK) {
1654 case ROOT_DESC_BITMAP:
1655 desc >>= ROOT_DESC_TYPE_SHIFT;
1657 if ((desc & 1) && *start_root) {
1658 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1664 case ROOT_DESC_COMPLEX: {
1665 gsize *bitmap_data = sgen_get_complex_descriptor_bitmap (desc);
1666 int bwords = (*bitmap_data) - 1;
1667 void **start_run = start_root;
1669 while (bwords-- > 0) {
1670 gsize bmap = *bitmap_data++;
1671 void **objptr = start_run;
1673 if ((bmap & 1) && *objptr) {
1674 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
1679 start_run += GC_BITS_PER_WORD;
1683 case ROOT_DESC_USER: {
1684 MonoGCRootMarkFunc marker = sgen_get_user_descriptor_func (desc);
1685 root_report = report;
1686 marker (start_root, single_arg_report_root);
1689 case ROOT_DESC_RUN_LEN:
1690 g_assert_not_reached ();
1692 g_assert_not_reached ();
1697 report_registered_roots_by_type (int root_type)
1699 GCRootReport report;
1703 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], start_root, root) {
1704 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
1705 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
1706 } SGEN_HASH_TABLE_FOREACH_END;
1707 notify_gc_roots (&report);
1711 report_registered_roots (void)
1713 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
1714 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
1718 scan_finalizer_entries (CopyOrMarkObjectFunc copy_func, FinalizeReadyEntry *list, GrayQueue *queue)
1720 FinalizeReadyEntry *fin;
1722 for (fin = list; fin; fin = fin->next) {
1725 SGEN_LOG (5, "Scan of fin ready object: %p (%s)\n", fin->object, safe_name (fin->object));
1726 copy_func (&fin->object, queue);
1731 generation_name (int generation)
1733 switch (generation) {
1734 case GENERATION_NURSERY: return "nursery";
1735 case GENERATION_OLD: return "old";
1736 default: g_assert_not_reached ();
1741 sgen_generation_name (int generation)
1743 return generation_name (generation);
1746 SgenObjectOperations *
1747 sgen_get_current_object_ops (void){
1748 return ¤t_object_ops;
1753 finish_gray_stack (char *start_addr, char *end_addr, int generation, GrayQueue *queue)
1757 int done_with_ephemerons, ephemeron_rounds = 0;
1758 CopyOrMarkObjectFunc copy_func = current_object_ops.copy_or_mark_object;
1761 * We copied all the reachable objects. Now it's the time to copy
1762 * the objects that were not referenced by the roots, but by the copied objects.
1763 * we built a stack of objects pointed to by gray_start: they are
1764 * additional roots and we may add more items as we go.
1765 * We loop until gray_start == gray_objects which means no more objects have
1766 * been added. Note this is iterative: no recursion is involved.
1767 * We need to walk the LO list as well in search of marked big objects
1768 * (use a flag since this is needed only on major collections). We need to loop
1769 * here as well, so keep a counter of marked LO (increasing it in copy_object).
1770 * To achieve better cache locality and cache usage, we drain the gray stack
1771 * frequently, after each object is copied, and just finish the work here.
1773 sgen_drain_gray_stack (queue, -1);
1775 SGEN_LOG (2, "%s generation done", generation_name (generation));
1778 Reset bridge data, we might have lingering data from a previous collection if this is a major
1779 collection trigged by minor overflow.
1781 We must reset the gathered bridges since their original block might be evacuated due to major
1782 fragmentation in the meanwhile and the bridge code should not have to deal with that.
1784 sgen_bridge_reset_data ();
1787 * Walk the ephemeron tables marking all values with reachable keys. This must be completely done
1788 * before processing finalizable objects or non-tracking weak hamdle to avoid finalizing/clearing
1789 * objects that are in fact reachable.
1791 done_with_ephemerons = 0;
1793 done_with_ephemerons = mark_ephemerons_in_range (copy_func, start_addr, end_addr, queue);
1794 sgen_drain_gray_stack (queue, -1);
1796 } while (!done_with_ephemerons);
1798 sgen_scan_togglerefs (copy_func, start_addr, end_addr, queue);
1799 if (generation == GENERATION_OLD)
1800 sgen_scan_togglerefs (copy_func, sgen_get_nursery_start (), sgen_get_nursery_end (), queue);
1802 if (sgen_need_bridge_processing ()) {
1803 sgen_collect_bridge_objects (copy_func, start_addr, end_addr, generation, queue);
1804 if (generation == GENERATION_OLD)
1805 sgen_collect_bridge_objects (copy_func, sgen_get_nursery_start (), sgen_get_nursery_end (), GENERATION_NURSERY, queue);
1809 Make sure we drain the gray stack before processing disappearing links and finalizers.
1810 If we don't make sure it is empty we might wrongly see a live object as dead.
1812 sgen_drain_gray_stack (queue, -1);
1815 We must clear weak links that don't track resurrection before processing object ready for
1816 finalization so they can be cleared before that.
1818 sgen_null_link_in_range (copy_func, start_addr, end_addr, generation, TRUE, queue);
1819 if (generation == GENERATION_OLD)
1820 sgen_null_link_in_range (copy_func, start_addr, end_addr, GENERATION_NURSERY, TRUE, queue);
1823 /* walk the finalization queue and move also the objects that need to be
1824 * finalized: use the finalized objects as new roots so the objects they depend
1825 * on are also not reclaimed. As with the roots above, only objects in the nursery
1826 * are marked/copied.
1828 sgen_finalize_in_range (copy_func, start_addr, end_addr, generation, queue);
1829 if (generation == GENERATION_OLD)
1830 sgen_finalize_in_range (copy_func, sgen_get_nursery_start (), sgen_get_nursery_end (), GENERATION_NURSERY, queue);
1831 /* drain the new stack that might have been created */
1832 SGEN_LOG (6, "Precise scan of gray area post fin");
1833 sgen_drain_gray_stack (queue, -1);
1836 * This must be done again after processing finalizable objects since CWL slots are cleared only after the key is finalized.
1838 done_with_ephemerons = 0;
1840 done_with_ephemerons = mark_ephemerons_in_range (copy_func, start_addr, end_addr, queue);
1841 sgen_drain_gray_stack (queue, -1);
1843 } while (!done_with_ephemerons);
1846 * Clear ephemeron pairs with unreachable keys.
1847 * We pass the copy func so we can figure out if an array was promoted or not.
1849 clear_unreachable_ephemerons (copy_func, start_addr, end_addr, queue);
1852 SGEN_LOG (2, "Finalize queue handling scan for %s generation: %d usecs %d ephemeron rounds", generation_name (generation), TV_ELAPSED (atv, btv), ephemeron_rounds);
1855 * handle disappearing links
1856 * Note we do this after checking the finalization queue because if an object
1857 * survives (at least long enough to be finalized) we don't clear the link.
1858 * This also deals with a possible issue with the monitor reclamation: with the Boehm
1859 * GC a finalized object my lose the monitor because it is cleared before the finalizer is
1862 g_assert (sgen_gray_object_queue_is_empty (queue));
1864 sgen_null_link_in_range (copy_func, start_addr, end_addr, generation, FALSE, queue);
1865 if (generation == GENERATION_OLD)
1866 sgen_null_link_in_range (copy_func, start_addr, end_addr, GENERATION_NURSERY, FALSE, queue);
1867 if (sgen_gray_object_queue_is_empty (queue))
1869 sgen_drain_gray_stack (queue, -1);
1872 g_assert (sgen_gray_object_queue_is_empty (queue));
1876 sgen_check_section_scan_starts (GCMemSection *section)
1879 for (i = 0; i < section->num_scan_start; ++i) {
1880 if (section->scan_starts [i]) {
1881 guint size = safe_object_get_size ((MonoObject*) section->scan_starts [i]);
1882 g_assert (size >= sizeof (MonoObject) && size <= MAX_SMALL_OBJ_SIZE);
1888 check_scan_starts (void)
1890 if (!do_scan_starts_check)
1892 sgen_check_section_scan_starts (nursery_section);
1893 major_collector.check_scan_starts ();
1897 scan_from_registered_roots (CopyOrMarkObjectFunc copy_func, char *addr_start, char *addr_end, int root_type, GrayQueue *queue)
1901 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], start_root, root) {
1902 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
1903 precisely_scan_objects_from (copy_func, start_root, (void**)root->end_root, addr_start, addr_end, root->root_desc, queue);
1904 } SGEN_HASH_TABLE_FOREACH_END;
1908 sgen_dump_occupied (char *start, char *end, char *section_start)
1910 fprintf (heap_dump_file, "<occupied offset=\"%td\" size=\"%td\"/>\n", start - section_start, end - start);
1914 sgen_dump_section (GCMemSection *section, const char *type)
1916 char *start = section->data;
1917 char *end = section->data + section->size;
1918 char *occ_start = NULL;
1920 char *old_start = NULL; /* just for debugging */
1922 fprintf (heap_dump_file, "<section type=\"%s\" size=\"%lu\">\n", type, (unsigned long)section->size);
1924 while (start < end) {
1928 if (!*(void**)start) {
1930 sgen_dump_occupied (occ_start, start, section->data);
1933 start += sizeof (void*); /* should be ALLOC_ALIGN, really */
1936 g_assert (start < section->next_data);
1941 vt = (GCVTable*)LOAD_VTABLE (start);
1944 size = ALIGN_UP (safe_object_get_size ((MonoObject*) start));
1947 fprintf (heap_dump_file, "<object offset=\"%d\" class=\"%s.%s\" size=\"%d\"/>\n",
1948 start - section->data,
1949 vt->klass->name_space, vt->klass->name,
1957 sgen_dump_occupied (occ_start, start, section->data);
1959 fprintf (heap_dump_file, "</section>\n");
1963 dump_object (MonoObject *obj, gboolean dump_location)
1965 static char class_name [1024];
1967 MonoClass *class = mono_object_class (obj);
1971 * Python's XML parser is too stupid to parse angle brackets
1972 * in strings, so we just ignore them;
1975 while (class->name [i] && j < sizeof (class_name) - 1) {
1976 if (!strchr ("<>\"", class->name [i]))
1977 class_name [j++] = class->name [i];
1980 g_assert (j < sizeof (class_name));
1983 fprintf (heap_dump_file, "<object class=\"%s.%s\" size=\"%d\"",
1984 class->name_space, class_name,
1985 safe_object_get_size (obj));
1986 if (dump_location) {
1987 const char *location;
1988 if (ptr_in_nursery (obj))
1989 location = "nursery";
1990 else if (safe_object_get_size (obj) <= MAX_SMALL_OBJ_SIZE)
1994 fprintf (heap_dump_file, " location=\"%s\"", location);
1996 fprintf (heap_dump_file, "/>\n");
2000 dump_heap (const char *type, int num, const char *reason)
2005 fprintf (heap_dump_file, "<collection type=\"%s\" num=\"%d\"", type, num);
2007 fprintf (heap_dump_file, " reason=\"%s\"", reason);
2008 fprintf (heap_dump_file, ">\n");
2009 fprintf (heap_dump_file, "<other-mem-usage type=\"mempools\" size=\"%ld\"/>\n", mono_mempool_get_bytes_allocated ());
2010 sgen_dump_internal_mem_usage (heap_dump_file);
2011 fprintf (heap_dump_file, "<pinned type=\"stack\" bytes=\"%zu\"/>\n", sgen_pin_stats_get_pinned_byte_count (PIN_TYPE_STACK));
2012 /* fprintf (heap_dump_file, "<pinned type=\"static-data\" bytes=\"%d\"/>\n", pinned_byte_counts [PIN_TYPE_STATIC_DATA]); */
2013 fprintf (heap_dump_file, "<pinned type=\"other\" bytes=\"%zu\"/>\n", sgen_pin_stats_get_pinned_byte_count (PIN_TYPE_OTHER));
2015 fprintf (heap_dump_file, "<pinned-objects>\n");
2016 for (list = sgen_pin_stats_get_object_list (); list; list = list->next)
2017 dump_object (list->obj, TRUE);
2018 fprintf (heap_dump_file, "</pinned-objects>\n");
2020 sgen_dump_section (nursery_section, "nursery");
2022 major_collector.dump_heap (heap_dump_file);
2024 fprintf (heap_dump_file, "<los>\n");
2025 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
2026 dump_object ((MonoObject*)bigobj->data, FALSE);
2027 fprintf (heap_dump_file, "</los>\n");
2029 fprintf (heap_dump_file, "</collection>\n");
2033 sgen_register_moved_object (void *obj, void *destination)
2035 g_assert (mono_profiler_events & MONO_PROFILE_GC_MOVES);
2037 /* FIXME: handle this for parallel collector */
2038 g_assert (!sgen_collection_is_parallel ());
2040 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2041 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2042 moved_objects_idx = 0;
2044 moved_objects [moved_objects_idx++] = obj;
2045 moved_objects [moved_objects_idx++] = destination;
2051 static gboolean inited = FALSE;
2056 mono_counters_register ("Minor fragment clear", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_pre_collection_fragment_clear);
2057 mono_counters_register ("Minor pinning", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_pinning);
2058 mono_counters_register ("Minor scan remembered set", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_scan_remsets);
2059 mono_counters_register ("Minor scan pinned", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_scan_pinned);
2060 mono_counters_register ("Minor scan registered roots", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_scan_registered_roots);
2061 mono_counters_register ("Minor scan thread data", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_scan_thread_data);
2062 mono_counters_register ("Minor finish gray stack", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_finish_gray_stack);
2063 mono_counters_register ("Minor fragment creation", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_minor_fragment_creation);
2065 mono_counters_register ("Major fragment clear", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_pre_collection_fragment_clear);
2066 mono_counters_register ("Major pinning", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_pinning);
2067 mono_counters_register ("Major scan pinned", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_scan_pinned);
2068 mono_counters_register ("Major scan registered roots", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_scan_registered_roots);
2069 mono_counters_register ("Major scan thread data", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_scan_thread_data);
2070 mono_counters_register ("Major scan alloc_pinned", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_scan_alloc_pinned);
2071 mono_counters_register ("Major scan finalized", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_scan_finalized);
2072 mono_counters_register ("Major scan big objects", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_scan_big_objects);
2073 mono_counters_register ("Major finish gray stack", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_finish_gray_stack);
2074 mono_counters_register ("Major free big objects", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_free_bigobjs);
2075 mono_counters_register ("Major LOS sweep", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_los_sweep);
2076 mono_counters_register ("Major sweep", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_sweep);
2077 mono_counters_register ("Major fragment creation", MONO_COUNTER_GC | MONO_COUNTER_TIME_INTERVAL, &time_major_fragment_creation);
2079 mono_counters_register ("Number of pinned objects", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_pinned_objects);
2081 #ifdef HEAVY_STATISTICS
2082 mono_counters_register ("WBarrier set field", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_set_field);
2083 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_set_arrayref);
2084 mono_counters_register ("WBarrier arrayref copy", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_arrayref_copy);
2085 mono_counters_register ("WBarrier generic store called", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_generic_store);
2086 mono_counters_register ("WBarrier set root", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_set_root);
2087 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_value_copy);
2088 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_INT, &stat_wbarrier_object_copy);
2090 mono_counters_register ("# objects allocated degraded", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_objects_alloced_degraded);
2091 mono_counters_register ("bytes allocated degraded", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_bytes_alloced_degraded);
2093 mono_counters_register ("# copy_object() called (nursery)", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_copy_object_called_nursery);
2094 mono_counters_register ("# objects copied (nursery)", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_objects_copied_nursery);
2095 mono_counters_register ("# copy_object() called (major)", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_copy_object_called_major);
2096 mono_counters_register ("# objects copied (major)", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_objects_copied_major);
2098 mono_counters_register ("# scan_object() called (nursery)", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_scan_object_called_nursery);
2099 mono_counters_register ("# scan_object() called (major)", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_scan_object_called_major);
2101 mono_counters_register ("Slots allocated in vain", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_slots_allocated_in_vain);
2103 mono_counters_register ("# nursery copy_object() failed from space", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_nursery_copy_object_failed_from_space);
2104 mono_counters_register ("# nursery copy_object() failed forwarded", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_nursery_copy_object_failed_forwarded);
2105 mono_counters_register ("# nursery copy_object() failed pinned", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_nursery_copy_object_failed_pinned);
2106 mono_counters_register ("# nursery copy_object() failed to space", MONO_COUNTER_GC | MONO_COUNTER_LONG, &stat_nursery_copy_object_failed_to_space);
2108 sgen_nursery_allocator_init_heavy_stats ();
2109 sgen_alloc_init_heavy_stats ();
2117 reset_pinned_from_failed_allocation (void)
2119 bytes_pinned_from_failed_allocation = 0;
2123 sgen_set_pinned_from_failed_allocation (mword objsize)
2125 bytes_pinned_from_failed_allocation += objsize;
2129 sgen_collection_is_parallel (void)
2131 switch (current_collection_generation) {
2132 case GENERATION_NURSERY:
2133 return nursery_collection_is_parallel;
2134 case GENERATION_OLD:
2135 return major_collector.is_parallel;
2137 g_error ("Invalid current generation %d", current_collection_generation);
2145 } FinishRememberedSetScanJobData;
2148 job_finish_remembered_set_scan (WorkerData *worker_data, void *job_data_untyped)
2150 FinishRememberedSetScanJobData *job_data = job_data_untyped;
2152 remset.finish_scan_remsets (job_data->heap_start, job_data->heap_end, sgen_workers_get_job_gray_queue (worker_data));
2157 CopyOrMarkObjectFunc func;
2161 } ScanFromRegisteredRootsJobData;
2164 job_scan_from_registered_roots (WorkerData *worker_data, void *job_data_untyped)
2166 ScanFromRegisteredRootsJobData *job_data = job_data_untyped;
2168 scan_from_registered_roots (job_data->func,
2169 job_data->heap_start, job_data->heap_end,
2170 job_data->root_type,
2171 sgen_workers_get_job_gray_queue (worker_data));
2178 } ScanThreadDataJobData;
2181 job_scan_thread_data (WorkerData *worker_data, void *job_data_untyped)
2183 ScanThreadDataJobData *job_data = job_data_untyped;
2185 scan_thread_data (job_data->heap_start, job_data->heap_end, TRUE,
2186 sgen_workers_get_job_gray_queue (worker_data));
2191 FinalizeReadyEntry *list;
2192 } ScanFinalizerEntriesJobData;
2195 job_scan_finalizer_entries (WorkerData *worker_data, void *job_data_untyped)
2197 ScanFinalizerEntriesJobData *job_data = job_data_untyped;
2199 scan_finalizer_entries (current_object_ops.copy_or_mark_object,
2201 sgen_workers_get_job_gray_queue (worker_data));
2205 verify_scan_starts (char *start, char *end)
2209 for (i = 0; i < nursery_section->num_scan_start; ++i) {
2210 char *addr = nursery_section->scan_starts [i];
2211 if (addr > start && addr < end)
2212 SGEN_LOG (1, "NFC-BAD SCAN START [%d] %p for obj [%p %p]", i, addr, start, end);
2217 verify_nursery (void)
2219 char *start, *end, *cur, *hole_start;
2221 if (!do_verify_nursery)
2224 /*This cleans up unused fragments */
2225 sgen_nursery_allocator_prepare_for_pinning ();
2227 hole_start = start = cur = sgen_get_nursery_start ();
2228 end = sgen_get_nursery_end ();
2233 if (!*(void**)cur) {
2234 cur += sizeof (void*);
2238 if (object_is_forwarded (cur))
2239 SGEN_LOG (1, "FORWARDED OBJ %p", cur);
2240 else if (object_is_pinned (cur))
2241 SGEN_LOG (1, "PINNED OBJ %p", cur);
2243 ss = safe_object_get_size ((MonoObject*)cur);
2244 size = ALIGN_UP (safe_object_get_size ((MonoObject*)cur));
2245 verify_scan_starts (cur, cur + size);
2246 if (do_dump_nursery_content) {
2247 if (cur > hole_start)
2248 SGEN_LOG (1, "HOLE [%p %p %d]", hole_start, cur, (int)(cur - hole_start));
2249 SGEN_LOG (1, "OBJ [%p %p %d %d %s %d]", cur, cur + size, (int)size, (int)ss, sgen_safe_name ((MonoObject*)cur), (gpointer)LOAD_VTABLE (cur) == sgen_get_array_fill_vtable ());
2257 * Collect objects in the nursery. Returns whether to trigger a major
2261 collect_nursery (void)
2263 gboolean needs_major;
2264 size_t max_garbage_amount;
2266 FinishRememberedSetScanJobData frssjd;
2267 ScanFromRegisteredRootsJobData scrrjd_normal, scrrjd_wbarrier;
2268 ScanFinalizerEntriesJobData sfejd_fin_ready, sfejd_critical_fin;
2269 ScanThreadDataJobData stdjd;
2270 mword fragment_total;
2271 TV_DECLARE (all_atv);
2272 TV_DECLARE (all_btv);
2276 if (disable_minor_collections)
2279 MONO_GC_BEGIN (GENERATION_NURSERY);
2283 #ifndef DISABLE_PERFCOUNTERS
2284 mono_perfcounters->gc_collections0++;
2287 current_collection_generation = GENERATION_NURSERY;
2288 if (sgen_collection_is_parallel ())
2289 current_object_ops = sgen_minor_collector.parallel_ops;
2291 current_object_ops = sgen_minor_collector.serial_ops;
2293 reset_pinned_from_failed_allocation ();
2295 binary_protocol_collection (stat_minor_gcs, GENERATION_NURSERY);
2296 check_scan_starts ();
2298 sgen_nursery_alloc_prepare_for_minor ();
2302 nursery_next = sgen_nursery_alloc_get_upper_alloc_bound ();
2303 /* FIXME: optimize later to use the higher address where an object can be present */
2304 nursery_next = MAX (nursery_next, sgen_get_nursery_end ());
2306 SGEN_LOG (1, "Start nursery collection %d %p-%p, size: %d", stat_minor_gcs, sgen_get_nursery_start (), nursery_next, (int)(nursery_next - sgen_get_nursery_start ()));
2307 max_garbage_amount = nursery_next - sgen_get_nursery_start ();
2308 g_assert (nursery_section->size >= max_garbage_amount);
2310 /* world must be stopped already */
2311 TV_GETTIME (all_atv);
2315 time_minor_pre_collection_fragment_clear += TV_ELAPSED (atv, btv);
2317 if (xdomain_checks) {
2318 sgen_clear_nursery_fragments ();
2319 check_for_xdomain_refs ();
2322 nursery_section->next_data = nursery_next;
2324 major_collector.start_nursery_collection ();
2326 sgen_memgov_minor_collection_start ();
2328 sgen_gray_object_queue_init (&gray_queue);
2329 sgen_workers_init_distribute_gray_queue ();
2332 gc_stats.minor_gc_count ++;
2334 if (remset.prepare_for_minor_collection)
2335 remset.prepare_for_minor_collection ();
2337 sgen_process_fin_stage_entries ();
2338 sgen_process_dislink_stage_entries ();
2340 /* pin from pinned handles */
2341 sgen_init_pinning ();
2342 mono_profiler_gc_event (MONO_GC_EVENT_MARK_START, 0);
2343 pin_from_roots (sgen_get_nursery_start (), nursery_next, WORKERS_DISTRIBUTE_GRAY_QUEUE);
2344 /* identify pinned objects */
2345 sgen_optimize_pin_queue (0);
2346 sgen_pinning_setup_section (nursery_section);
2347 sgen_pin_objects_in_section (nursery_section, WORKERS_DISTRIBUTE_GRAY_QUEUE);
2348 sgen_pinning_trim_queue_to_section (nursery_section);
2351 time_minor_pinning += TV_ELAPSED (btv, atv);
2352 SGEN_LOG (2, "Finding pinned pointers: %d in %d usecs", sgen_get_pinned_count (), TV_ELAPSED (btv, atv));
2353 SGEN_LOG (4, "Start scan with %d pinned objects", sgen_get_pinned_count ());
2355 if (whole_heap_check_before_collection)
2356 sgen_check_whole_heap ();
2357 if (consistency_check_at_minor_collection)
2358 sgen_check_consistency ();
2360 sgen_workers_start_all_workers ();
2363 * Perform the sequential part of remembered set scanning.
2364 * This usually involves scanning global information that might later be produced by evacuation.
2366 if (remset.begin_scan_remsets)
2367 remset.begin_scan_remsets (sgen_get_nursery_start (), nursery_next, WORKERS_DISTRIBUTE_GRAY_QUEUE);
2369 sgen_workers_start_marking ();
2371 frssjd.heap_start = sgen_get_nursery_start ();
2372 frssjd.heap_end = nursery_next;
2373 sgen_workers_enqueue_job (job_finish_remembered_set_scan, &frssjd);
2375 /* we don't have complete write barrier yet, so we scan all the old generation sections */
2377 time_minor_scan_remsets += TV_ELAPSED (atv, btv);
2378 SGEN_LOG (2, "Old generation scan: %d usecs", TV_ELAPSED (atv, btv));
2380 if (!sgen_collection_is_parallel ())
2381 sgen_drain_gray_stack (&gray_queue, -1);
2383 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2384 report_registered_roots ();
2385 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2386 report_finalizer_roots ();
2388 time_minor_scan_pinned += TV_ELAPSED (btv, atv);
2390 /* registered roots, this includes static fields */
2391 scrrjd_normal.func = current_object_ops.copy_or_mark_object;
2392 scrrjd_normal.heap_start = sgen_get_nursery_start ();
2393 scrrjd_normal.heap_end = nursery_next;
2394 scrrjd_normal.root_type = ROOT_TYPE_NORMAL;
2395 sgen_workers_enqueue_job (job_scan_from_registered_roots, &scrrjd_normal);
2397 scrrjd_wbarrier.func = current_object_ops.copy_or_mark_object;
2398 scrrjd_wbarrier.heap_start = sgen_get_nursery_start ();
2399 scrrjd_wbarrier.heap_end = nursery_next;
2400 scrrjd_wbarrier.root_type = ROOT_TYPE_WBARRIER;
2401 sgen_workers_enqueue_job (job_scan_from_registered_roots, &scrrjd_wbarrier);
2404 time_minor_scan_registered_roots += TV_ELAPSED (atv, btv);
2407 stdjd.heap_start = sgen_get_nursery_start ();
2408 stdjd.heap_end = nursery_next;
2409 sgen_workers_enqueue_job (job_scan_thread_data, &stdjd);
2412 time_minor_scan_thread_data += TV_ELAPSED (btv, atv);
2415 if (sgen_collection_is_parallel ()) {
2416 while (!sgen_gray_object_queue_is_empty (WORKERS_DISTRIBUTE_GRAY_QUEUE)) {
2417 sgen_workers_distribute_gray_queue_sections ();
2421 sgen_workers_join ();
2423 if (sgen_collection_is_parallel ())
2424 g_assert (sgen_gray_object_queue_is_empty (&gray_queue));
2426 /* Scan the list of objects ready for finalization. If */
2427 sfejd_fin_ready.list = fin_ready_list;
2428 sgen_workers_enqueue_job (job_scan_finalizer_entries, &sfejd_fin_ready);
2430 sfejd_critical_fin.list = critical_fin_list;
2431 sgen_workers_enqueue_job (job_scan_finalizer_entries, &sfejd_critical_fin);
2433 finish_gray_stack (sgen_get_nursery_start (), nursery_next, GENERATION_NURSERY, &gray_queue);
2435 time_minor_finish_gray_stack += TV_ELAPSED (btv, atv);
2436 mono_profiler_gc_event (MONO_GC_EVENT_MARK_END, 0);
2439 * The (single-threaded) finalization code might have done
2440 * some copying/marking so we can only reset the GC thread's
2441 * worker data here instead of earlier when we joined the
2444 sgen_workers_reset_data ();
2446 if (objects_pinned) {
2447 sgen_optimize_pin_queue (0);
2448 sgen_pinning_setup_section (nursery_section);
2451 /* walk the pin_queue, build up the fragment list of free memory, unmark
2452 * pinned objects as we go, memzero() the empty fragments so they are ready for the
2455 mono_profiler_gc_event (MONO_GC_EVENT_RECLAIM_START, 0);
2456 fragment_total = sgen_build_nursery_fragments (nursery_section, nursery_section->pin_queue_start, nursery_section->pin_queue_num_entries);
2457 if (!fragment_total)
2460 /* Clear TLABs for all threads */
2461 sgen_clear_tlabs ();
2463 mono_profiler_gc_event (MONO_GC_EVENT_RECLAIM_END, 0);
2465 time_minor_fragment_creation += TV_ELAPSED (atv, btv);
2466 SGEN_LOG (2, "Fragment creation: %d usecs, %lu bytes available", TV_ELAPSED (atv, btv), (unsigned long)fragment_total);
2468 if (consistency_check_at_minor_collection)
2469 sgen_check_major_refs ();
2471 major_collector.finish_nursery_collection ();
2473 TV_GETTIME (all_btv);
2474 gc_stats.minor_gc_time_usecs += TV_ELAPSED (all_atv, all_btv);
2477 dump_heap ("minor", stat_minor_gcs - 1, NULL);
2479 /* prepare the pin queue for the next collection */
2480 sgen_finish_pinning ();
2481 if (fin_ready_list || critical_fin_list) {
2482 SGEN_LOG (4, "Finalizer-thread wakeup: ready %d", num_ready_finalizers);
2483 mono_gc_finalize_notify ();
2485 sgen_pin_stats_reset ();
2487 g_assert (sgen_gray_object_queue_is_empty (&gray_queue));
2489 if (remset.finish_minor_collection)
2490 remset.finish_minor_collection ();
2492 check_scan_starts ();
2494 binary_protocol_flush_buffers (FALSE);
2496 sgen_memgov_minor_collection_end ();
2498 /*objects are late pinned because of lack of memory, so a major is a good call*/
2499 needs_major = objects_pinned > 0;
2500 current_collection_generation = -1;
2503 MONO_GC_END (GENERATION_NURSERY);
2509 major_do_collection (const char *reason)
2511 LOSObject *bigobj, *prevbo;
2512 TV_DECLARE (all_atv);
2513 TV_DECLARE (all_btv);
2516 /* FIXME: only use these values for the precise scan
2517 * note that to_space pointers should be excluded anyway...
2519 char *heap_start = NULL;
2520 char *heap_end = (char*)-1;
2521 int old_next_pin_slot;
2522 ScanFromRegisteredRootsJobData scrrjd_normal, scrrjd_wbarrier;
2523 ScanThreadDataJobData stdjd;
2524 ScanFinalizerEntriesJobData sfejd_fin_ready, sfejd_critical_fin;
2526 MONO_GC_BEGIN (GENERATION_OLD);
2528 current_collection_generation = GENERATION_OLD;
2529 #ifndef DISABLE_PERFCOUNTERS
2530 mono_perfcounters->gc_collections1++;
2533 current_object_ops = major_collector.major_ops;
2535 reset_pinned_from_failed_allocation ();
2537 sgen_memgov_major_collection_start ();
2539 //count_ref_nonref_objs ();
2540 //consistency_check ();
2542 binary_protocol_collection (stat_major_gcs, GENERATION_OLD);
2543 check_scan_starts ();
2545 sgen_gray_object_queue_init (&gray_queue);
2546 sgen_workers_init_distribute_gray_queue ();
2547 sgen_nursery_alloc_prepare_for_major ();
2550 SGEN_LOG (1, "Start major collection %d", stat_major_gcs);
2552 gc_stats.major_gc_count ++;
2554 /* world must be stopped already */
2555 TV_GETTIME (all_atv);
2558 /* Pinning depends on this */
2559 sgen_clear_nursery_fragments ();
2561 if (whole_heap_check_before_collection)
2562 sgen_check_whole_heap ();
2565 time_major_pre_collection_fragment_clear += TV_ELAPSED (atv, btv);
2567 nursery_section->next_data = sgen_get_nursery_end ();
2568 /* we should also coalesce scanning from sections close to each other
2569 * and deal with pointers outside of the sections later.
2572 if (major_collector.start_major_collection)
2573 major_collector.start_major_collection ();
2576 *major_collector.have_swept = FALSE;
2578 if (xdomain_checks) {
2579 sgen_clear_nursery_fragments ();
2580 check_for_xdomain_refs ();
2583 /* Remsets are not useful for a major collection */
2584 remset.prepare_for_major_collection ();
2586 sgen_process_fin_stage_entries ();
2587 sgen_process_dislink_stage_entries ();
2590 sgen_init_pinning ();
2591 SGEN_LOG (6, "Collecting pinned addresses");
2592 pin_from_roots ((void*)lowest_heap_address, (void*)highest_heap_address, WORKERS_DISTRIBUTE_GRAY_QUEUE);
2593 sgen_optimize_pin_queue (0);
2596 * pin_queue now contains all candidate pointers, sorted and
2597 * uniqued. We must do two passes now to figure out which
2598 * objects are pinned.
2600 * The first is to find within the pin_queue the area for each
2601 * section. This requires that the pin_queue be sorted. We
2602 * also process the LOS objects and pinned chunks here.
2604 * The second, destructive, pass is to reduce the section
2605 * areas to pointers to the actually pinned objects.
2607 SGEN_LOG (6, "Pinning from sections");
2608 /* first pass for the sections */
2609 sgen_find_section_pin_queue_start_end (nursery_section);
2610 major_collector.find_pin_queue_start_ends (WORKERS_DISTRIBUTE_GRAY_QUEUE);
2611 /* identify possible pointers to the insize of large objects */
2612 SGEN_LOG (6, "Pinning from large objects");
2613 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next) {
2615 gboolean profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2616 GCRootReport report;
2618 if (sgen_find_optimized_pin_queue_area (bigobj->data, (char*)bigobj->data + bigobj->size, &dummy)) {
2619 binary_protocol_pin (bigobj->data, (gpointer)LOAD_VTABLE (bigobj->data), safe_object_get_size (((MonoObject*)(bigobj->data))));
2620 if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {
2621 MonoVTable *vt = (MonoVTable*)LOAD_VTABLE (bigobj->data);
2622 MONO_GC_OBJ_PINNED ((mword)bigobj->data, sgen_safe_object_get_size ((MonoObject*)bigobj->data), vt->klass->name_space, vt->klass->name, GENERATION_OLD);
2624 pin_object (bigobj->data);
2625 /* FIXME: only enqueue if object has references */
2626 GRAY_OBJECT_ENQUEUE (WORKERS_DISTRIBUTE_GRAY_QUEUE, bigobj->data);
2627 if (G_UNLIKELY (do_pin_stats))
2628 sgen_pin_stats_register_object ((char*) bigobj->data, safe_object_get_size ((MonoObject*) bigobj->data));
2629 SGEN_LOG (6, "Marked large object %p (%s) size: %lu from roots", bigobj->data, safe_name (bigobj->data), (unsigned long)bigobj->size);
2632 add_profile_gc_root (&report, bigobj->data, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2635 notify_gc_roots (&report);
2637 /* second pass for the sections */
2638 sgen_pin_objects_in_section (nursery_section, WORKERS_DISTRIBUTE_GRAY_QUEUE);
2639 major_collector.pin_objects (WORKERS_DISTRIBUTE_GRAY_QUEUE);
2640 old_next_pin_slot = sgen_get_pinned_count ();
2643 time_major_pinning += TV_ELAPSED (atv, btv);
2644 SGEN_LOG (2, "Finding pinned pointers: %d in %d usecs", sgen_get_pinned_count (), TV_ELAPSED (atv, btv));
2645 SGEN_LOG (4, "Start scan with %d pinned objects", sgen_get_pinned_count ());
2647 major_collector.init_to_space ();
2649 #ifdef SGEN_DEBUG_INTERNAL_ALLOC
2650 main_gc_thread = mono_native_thread_self ();
2653 sgen_workers_start_all_workers ();
2654 sgen_workers_start_marking ();
2656 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2657 report_registered_roots ();
2659 time_major_scan_pinned += TV_ELAPSED (btv, atv);
2661 /* registered roots, this includes static fields */
2662 scrrjd_normal.func = current_object_ops.copy_or_mark_object;
2663 scrrjd_normal.heap_start = heap_start;
2664 scrrjd_normal.heap_end = heap_end;
2665 scrrjd_normal.root_type = ROOT_TYPE_NORMAL;
2666 sgen_workers_enqueue_job (job_scan_from_registered_roots, &scrrjd_normal);
2668 scrrjd_wbarrier.func = current_object_ops.copy_or_mark_object;
2669 scrrjd_wbarrier.heap_start = heap_start;
2670 scrrjd_wbarrier.heap_end = heap_end;
2671 scrrjd_wbarrier.root_type = ROOT_TYPE_WBARRIER;
2672 sgen_workers_enqueue_job (job_scan_from_registered_roots, &scrrjd_wbarrier);
2675 time_major_scan_registered_roots += TV_ELAPSED (atv, btv);
2678 stdjd.heap_start = heap_start;
2679 stdjd.heap_end = heap_end;
2680 sgen_workers_enqueue_job (job_scan_thread_data, &stdjd);
2683 time_major_scan_thread_data += TV_ELAPSED (btv, atv);
2686 time_major_scan_alloc_pinned += TV_ELAPSED (atv, btv);
2688 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2689 report_finalizer_roots ();
2691 /* scan the list of objects ready for finalization */
2692 sfejd_fin_ready.list = fin_ready_list;
2693 sgen_workers_enqueue_job (job_scan_finalizer_entries, &sfejd_fin_ready);
2695 sfejd_critical_fin.list = critical_fin_list;
2696 sgen_workers_enqueue_job (job_scan_finalizer_entries, &sfejd_critical_fin);
2699 time_major_scan_finalized += TV_ELAPSED (btv, atv);
2700 SGEN_LOG (2, "Root scan: %d usecs", TV_ELAPSED (btv, atv));
2703 time_major_scan_big_objects += TV_ELAPSED (atv, btv);
2705 if (major_collector.is_parallel) {
2706 while (!sgen_gray_object_queue_is_empty (WORKERS_DISTRIBUTE_GRAY_QUEUE)) {
2707 sgen_workers_distribute_gray_queue_sections ();
2711 sgen_workers_join ();
2713 #ifdef SGEN_DEBUG_INTERNAL_ALLOC
2714 main_gc_thread = NULL;
2717 if (major_collector.is_parallel)
2718 g_assert (sgen_gray_object_queue_is_empty (&gray_queue));
2720 /* all the objects in the heap */
2721 finish_gray_stack (heap_start, heap_end, GENERATION_OLD, &gray_queue);
2723 time_major_finish_gray_stack += TV_ELAPSED (btv, atv);
2726 * The (single-threaded) finalization code might have done
2727 * some copying/marking so we can only reset the GC thread's
2728 * worker data here instead of earlier when we joined the
2731 sgen_workers_reset_data ();
2733 if (objects_pinned) {
2734 /*This is slow, but we just OOM'd*/
2735 sgen_pin_queue_clear_discarded_entries (nursery_section, old_next_pin_slot);
2736 sgen_optimize_pin_queue (0);
2737 sgen_find_section_pin_queue_start_end (nursery_section);
2741 reset_heap_boundaries ();
2742 sgen_update_heap_boundaries ((mword)sgen_get_nursery_start (), (mword)sgen_get_nursery_end ());
2744 /* sweep the big objects list */
2746 for (bigobj = los_object_list; bigobj;) {
2747 if (object_is_pinned (bigobj->data)) {
2748 unpin_object (bigobj->data);
2749 sgen_update_heap_boundaries ((mword)bigobj->data, (mword)bigobj->data + bigobj->size);
2752 /* not referenced anywhere, so we can free it */
2754 prevbo->next = bigobj->next;
2756 los_object_list = bigobj->next;
2758 bigobj = bigobj->next;
2759 sgen_los_free_object (to_free);
2763 bigobj = bigobj->next;
2767 time_major_free_bigobjs += TV_ELAPSED (atv, btv);
2772 time_major_los_sweep += TV_ELAPSED (btv, atv);
2774 major_collector.sweep ();
2777 time_major_sweep += TV_ELAPSED (atv, btv);
2779 /* walk the pin_queue, build up the fragment list of free memory, unmark
2780 * pinned objects as we go, memzero() the empty fragments so they are ready for the
2783 if (!sgen_build_nursery_fragments (nursery_section, nursery_section->pin_queue_start, nursery_section->pin_queue_num_entries))
2786 /* Clear TLABs for all threads */
2787 sgen_clear_tlabs ();
2790 time_major_fragment_creation += TV_ELAPSED (btv, atv);
2792 TV_GETTIME (all_btv);
2793 gc_stats.major_gc_time_usecs += TV_ELAPSED (all_atv, all_btv);
2796 dump_heap ("major", stat_major_gcs - 1, reason);
2798 /* prepare the pin queue for the next collection */
2799 sgen_finish_pinning ();
2801 if (fin_ready_list || critical_fin_list) {
2802 SGEN_LOG (4, "Finalizer-thread wakeup: ready %d", num_ready_finalizers);
2803 mono_gc_finalize_notify ();
2805 sgen_pin_stats_reset ();
2807 g_assert (sgen_gray_object_queue_is_empty (&gray_queue));
2809 sgen_memgov_major_collection_end ();
2810 current_collection_generation = -1;
2812 major_collector.finish_major_collection ();
2814 check_scan_starts ();
2816 binary_protocol_flush_buffers (FALSE);
2818 //consistency_check ();
2820 MONO_GC_END (GENERATION_OLD);
2822 return bytes_pinned_from_failed_allocation > 0;
2825 static gboolean major_do_collection (const char *reason);
2828 * Ensure an allocation request for @size will succeed by freeing enough memory.
2830 * LOCKING: The GC lock MUST be held.
2833 sgen_ensure_free_space (size_t size)
2835 int generation_to_collect = -1;
2836 const char *reason = NULL;
2839 if (size > SGEN_MAX_SMALL_OBJ_SIZE) {
2840 if (sgen_need_major_collection (size)) {
2841 reason = "LOS overflow";
2842 generation_to_collect = GENERATION_OLD;
2845 if (degraded_mode) {
2846 if (sgen_need_major_collection (size)) {
2847 reason = "Degraded mode overflow";
2848 generation_to_collect = GENERATION_OLD;
2850 } else if (sgen_need_major_collection (size)) {
2851 reason = "Minor allowance";
2852 generation_to_collect = GENERATION_OLD;
2854 generation_to_collect = GENERATION_NURSERY;
2855 reason = "Nursery full";
2859 if (generation_to_collect == -1)
2861 sgen_perform_collection (size, generation_to_collect, reason);
2865 sgen_perform_collection (size_t requested_size, int generation_to_collect, const char *reason)
2867 TV_DECLARE (gc_end);
2868 GGTimingInfo infos [2];
2869 int overflow_generation_to_collect = -1;
2870 const char *overflow_reason = NULL;
2872 memset (infos, 0, sizeof (infos));
2873 mono_profiler_gc_event (MONO_GC_EVENT_START, generation_to_collect);
2875 infos [0].generation = generation_to_collect;
2876 infos [0].reason = reason;
2877 infos [0].is_overflow = FALSE;
2878 TV_GETTIME (infos [0].total_time);
2879 infos [1].generation = -1;
2881 sgen_stop_world (generation_to_collect);
2882 //FIXME extract overflow reason
2883 if (generation_to_collect == GENERATION_NURSERY) {
2884 if (collect_nursery ()) {
2885 overflow_generation_to_collect = GENERATION_OLD;
2886 overflow_reason = "Minor overflow";
2889 if (major_do_collection (reason)) {
2890 overflow_generation_to_collect = GENERATION_NURSERY;
2891 overflow_reason = "Excessive pinning";
2895 TV_GETTIME (gc_end);
2896 infos [0].total_time = SGEN_TV_ELAPSED (infos [0].total_time, gc_end);
2899 if (overflow_generation_to_collect != -1) {
2900 mono_profiler_gc_event (MONO_GC_EVENT_START, overflow_generation_to_collect);
2901 infos [1].generation = overflow_generation_to_collect;
2902 infos [1].reason = overflow_reason;
2903 infos [1].is_overflow = TRUE;
2904 infos [1].total_time = gc_end;
2906 if (overflow_generation_to_collect == GENERATION_NURSERY)
2909 major_do_collection (overflow_reason);
2911 TV_GETTIME (gc_end);
2912 infos [1].total_time = SGEN_TV_ELAPSED (infos [1].total_time, gc_end);
2914 /* keep events symmetric */
2915 mono_profiler_gc_event (MONO_GC_EVENT_END, overflow_generation_to_collect);
2918 SGEN_LOG (2, "Heap size: %lu, LOS size: %lu", (unsigned long)mono_gc_get_heap_size (), (unsigned long)los_memory_usage);
2920 /* this also sets the proper pointers for the next allocation */
2921 if (generation_to_collect == GENERATION_NURSERY && !sgen_can_alloc_size (requested_size)) {
2922 /* TypeBuilder and MonoMethod are killing mcs with fragmentation */
2923 SGEN_LOG (1, "nursery collection didn't find enough room for %zd alloc (%d pinned)", requested_size, sgen_get_pinned_count ());
2924 sgen_dump_pin_queue ();
2928 sgen_restart_world (generation_to_collect, infos);
2930 mono_profiler_gc_event (MONO_GC_EVENT_END, generation_to_collect);
2934 * ######################################################################
2935 * ######## Memory allocation from the OS
2936 * ######################################################################
2937 * This section of code deals with getting memory from the OS and
2938 * allocating memory for GC-internal data structures.
2939 * Internal memory can be handled with a freelist for small objects.
2945 G_GNUC_UNUSED static void
2946 report_internal_mem_usage (void)
2948 printf ("Internal memory usage:\n");
2949 sgen_report_internal_mem_usage ();
2950 printf ("Pinned memory usage:\n");
2951 major_collector.report_pinned_memory_usage ();
2955 * ######################################################################
2956 * ######## Finalization support
2957 * ######################################################################
2961 * If the object has been forwarded it means it's still referenced from a root.
2962 * If it is pinned it's still alive as well.
2963 * A LOS object is only alive if we have pinned it.
2964 * Return TRUE if @obj is ready to be finalized.
2966 static inline gboolean
2967 sgen_is_object_alive (void *object)
2969 if (ptr_in_nursery (object))
2970 return sgen_nursery_is_object_alive (object);
2971 /* Oldgen objects can be pinned and forwarded too */
2972 if (SGEN_OBJECT_IS_PINNED (object) || SGEN_OBJECT_IS_FORWARDED (object))
2974 return major_collector.is_object_live (object);
2978 sgen_gc_is_object_ready_for_finalization (void *object)
2980 return !sgen_is_object_alive (object);
2984 has_critical_finalizer (MonoObject *obj)
2988 if (!mono_defaults.critical_finalizer_object)
2991 class = ((MonoVTable*)LOAD_VTABLE (obj))->klass;
2993 return mono_class_has_parent_fast (class, mono_defaults.critical_finalizer_object);
2997 sgen_queue_finalization_entry (MonoObject *obj)
2999 FinalizeReadyEntry *entry = sgen_alloc_internal (INTERNAL_MEM_FINALIZE_READY_ENTRY);
3000 entry->object = obj;
3001 if (has_critical_finalizer (obj)) {
3002 entry->next = critical_fin_list;
3003 critical_fin_list = entry;
3005 entry->next = fin_ready_list;
3006 fin_ready_list = entry;
3011 object_is_reachable (char *object, char *start, char *end)
3013 /*This happens for non nursery objects during minor collections. We just treat all objects as alive.*/
3014 if (object < start || object >= end)
3017 return sgen_is_object_alive (object);
3021 sgen_object_is_live (void *obj)
3023 if (ptr_in_nursery (obj))
3024 return object_is_pinned (obj);
3025 /* FIXME This is semantically wrong! All tenured object are considered alive during a nursery collection. */
3026 if (current_collection_generation == GENERATION_NURSERY)
3028 return major_collector.is_object_live (obj);
3031 /* LOCKING: requires that the GC lock is held */
3033 null_ephemerons_for_domain (MonoDomain *domain)
3035 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
3038 MonoObject *object = (MonoObject*)current->array;
3040 if (object && !object->vtable) {
3041 EphemeronLinkNode *tmp = current;
3044 prev->next = current->next;
3046 ephemeron_list = current->next;
3048 current = current->next;
3049 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
3052 current = current->next;
3057 /* LOCKING: requires that the GC lock is held */
3059 clear_unreachable_ephemerons (CopyOrMarkObjectFunc copy_func, char *start, char *end, GrayQueue *queue)
3061 int was_in_nursery, was_promoted;
3062 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
3064 Ephemeron *cur, *array_end;
3068 char *object = current->array;
3070 if (!object_is_reachable (object, start, end)) {
3071 EphemeronLinkNode *tmp = current;
3073 SGEN_LOG (5, "Dead Ephemeron array at %p", object);
3076 prev->next = current->next;
3078 ephemeron_list = current->next;
3080 current = current->next;
3081 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
3086 was_in_nursery = ptr_in_nursery (object);
3087 copy_func ((void**)&object, queue);
3088 current->array = object;
3090 /*The array was promoted, add global remsets for key/values left behind in nursery.*/
3091 was_promoted = was_in_nursery && !ptr_in_nursery (object);
3093 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", object);
3095 array = (MonoArray*)object;
3096 cur = mono_array_addr (array, Ephemeron, 0);
3097 array_end = cur + mono_array_length_fast (array);
3098 tombstone = (char*)((MonoVTable*)LOAD_VTABLE (object))->domain->ephemeron_tombstone;
3100 for (; cur < array_end; ++cur) {
3101 char *key = (char*)cur->key;
3103 if (!key || key == tombstone)
3106 SGEN_LOG (5, "[%td] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
3107 key, object_is_reachable (key, start, end) ? "reachable" : "unreachable",
3108 cur->value, cur->value && object_is_reachable (cur->value, start, end) ? "reachable" : "unreachable");
3110 if (!object_is_reachable (key, start, end)) {
3111 cur->key = tombstone;
3117 if (ptr_in_nursery (key)) {/*key was not promoted*/
3118 SGEN_LOG (5, "\tAdded remset to key %p", key);
3119 sgen_add_to_global_remset (&cur->key);
3121 if (ptr_in_nursery (cur->value)) {/*value was not promoted*/
3122 SGEN_LOG (5, "\tAdded remset to value %p", cur->value);
3123 sgen_add_to_global_remset (&cur->value);
3128 current = current->next;
3132 /* LOCKING: requires that the GC lock is held */
3134 mark_ephemerons_in_range (CopyOrMarkObjectFunc copy_func, char *start, char *end, GrayQueue *queue)
3136 int nothing_marked = 1;
3137 EphemeronLinkNode *current = ephemeron_list;
3139 Ephemeron *cur, *array_end;
3142 for (current = ephemeron_list; current; current = current->next) {
3143 char *object = current->array;
3144 SGEN_LOG (5, "Ephemeron array at %p", object);
3147 For now we process all ephemerons during all collections.
3148 Ideally we should use remset information to partially scan those
3150 We already emit write barriers for Ephemeron fields, it's
3151 just that we don't process them.
3153 /*if (object < start || object >= end)
3156 /*It has to be alive*/
3157 if (!object_is_reachable (object, start, end)) {
3158 SGEN_LOG (5, "\tnot reachable");
3162 copy_func ((void**)&object, queue);
3164 array = (MonoArray*)object;
3165 cur = mono_array_addr (array, Ephemeron, 0);
3166 array_end = cur + mono_array_length_fast (array);
3167 tombstone = (char*)((MonoVTable*)LOAD_VTABLE (object))->domain->ephemeron_tombstone;
3169 for (; cur < array_end; ++cur) {
3170 char *key = cur->key;
3172 if (!key || key == tombstone)
3175 SGEN_LOG (5, "[%td] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
3176 key, object_is_reachable (key, start, end) ? "reachable" : "unreachable",
3177 cur->value, cur->value && object_is_reachable (cur->value, start, end) ? "reachable" : "unreachable");
3179 if (object_is_reachable (key, start, end)) {
3180 char *value = cur->value;
3182 copy_func ((void**)&cur->key, queue);
3184 if (!object_is_reachable (value, start, end))
3186 copy_func ((void**)&cur->value, queue);
3192 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
3193 return nothing_marked;
3197 mono_gc_invoke_finalizers (void)
3199 FinalizeReadyEntry *entry = NULL;
3200 gboolean entry_is_critical = FALSE;
3203 /* FIXME: batch to reduce lock contention */
3204 while (fin_ready_list || critical_fin_list) {
3208 FinalizeReadyEntry **list = entry_is_critical ? &critical_fin_list : &fin_ready_list;
3210 /* We have finalized entry in the last
3211 interation, now we need to remove it from
3214 *list = entry->next;
3216 FinalizeReadyEntry *e = *list;
3217 while (e->next != entry)
3219 e->next = entry->next;
3221 sgen_free_internal (entry, INTERNAL_MEM_FINALIZE_READY_ENTRY);
3225 /* Now look for the first non-null entry. */
3226 for (entry = fin_ready_list; entry && !entry->object; entry = entry->next)
3229 entry_is_critical = FALSE;
3231 entry_is_critical = TRUE;
3232 for (entry = critical_fin_list; entry && !entry->object; entry = entry->next)
3237 g_assert (entry->object);
3238 num_ready_finalizers--;
3239 obj = entry->object;
3240 entry->object = NULL;
3241 SGEN_LOG (7, "Finalizing object %p (%s)", obj, safe_name (obj));
3249 g_assert (entry->object == NULL);
3251 /* the object is on the stack so it is pinned */
3252 /*g_print ("Calling finalizer for object: %p (%s)\n", entry->object, safe_name (entry->object));*/
3253 mono_gc_run_finalize (obj, NULL);
3260 mono_gc_pending_finalizers (void)
3262 return fin_ready_list || critical_fin_list;
3266 * ######################################################################
3267 * ######## registered roots support
3268 * ######################################################################
3272 * We do not coalesce roots.
3275 mono_gc_register_root_inner (char *start, size_t size, void *descr, int root_type)
3277 RootRecord new_root;
3280 for (i = 0; i < ROOT_TYPE_NUM; ++i) {
3281 RootRecord *root = sgen_hash_table_lookup (&roots_hash [i], start);
3282 /* we allow changing the size and the descriptor (for thread statics etc) */
3284 size_t old_size = root->end_root - start;
3285 root->end_root = start + size;
3286 g_assert (((root->root_desc != 0) && (descr != NULL)) ||
3287 ((root->root_desc == 0) && (descr == NULL)));
3288 root->root_desc = (mword)descr;
3290 roots_size -= old_size;
3296 new_root.end_root = start + size;
3297 new_root.root_desc = (mword)descr;
3299 sgen_hash_table_replace (&roots_hash [root_type], start, &new_root, NULL);
3302 SGEN_LOG (3, "Added root for range: %p-%p, descr: %p (%d/%d bytes)", start, new_root.end_root, descr, (int)size, (int)roots_size);
3309 mono_gc_register_root (char *start, size_t size, void *descr)
3311 return mono_gc_register_root_inner (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED);
3315 mono_gc_register_root_wbarrier (char *start, size_t size, void *descr)
3317 return mono_gc_register_root_inner (start, size, descr, ROOT_TYPE_WBARRIER);
3321 mono_gc_deregister_root (char* addr)
3327 for (root_type = 0; root_type < ROOT_TYPE_NUM; ++root_type) {
3328 if (sgen_hash_table_remove (&roots_hash [root_type], addr, &root))
3329 roots_size -= (root.end_root - addr);
3335 * ######################################################################
3336 * ######## Thread handling (stop/start code)
3337 * ######################################################################
3340 unsigned int sgen_global_stop_count = 0;
3343 sgen_fill_thread_info_for_suspend (SgenThreadInfo *info)
3345 if (remset.fill_thread_info_for_suspend)
3346 remset.fill_thread_info_for_suspend (info);
3350 sgen_get_current_collection_generation (void)
3352 return current_collection_generation;
3356 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
3358 gc_callbacks = *callbacks;
3362 mono_gc_get_gc_callbacks ()
3364 return &gc_callbacks;
3367 /* Variables holding start/end nursery so it won't have to be passed at every call */
3368 static void *scan_area_arg_start, *scan_area_arg_end;
3371 mono_gc_conservatively_scan_area (void *start, void *end)
3373 conservatively_pin_objects_from (start, end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
3377 mono_gc_scan_object (void *obj)
3379 UserCopyOrMarkData *data = mono_native_tls_get_value (user_copy_or_mark_key);
3380 current_object_ops.copy_or_mark_object (&obj, data->queue);
3385 * Mark from thread stacks and registers.
3388 scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, GrayQueue *queue)
3390 SgenThreadInfo *info;
3392 scan_area_arg_start = start_nursery;
3393 scan_area_arg_end = end_nursery;
3395 FOREACH_THREAD (info) {
3397 SGEN_LOG (3, "Skipping dead thread %p, range: %p-%p, size: %td", info, info->stack_start, info->stack_end, (char*)info->stack_end - (char*)info->stack_start);
3400 if (info->gc_disabled) {
3401 SGEN_LOG (3, "GC disabled for thread %p, range: %p-%p, size: %td", info, info->stack_start, info->stack_end, (char*)info->stack_end - (char*)info->stack_start);
3405 if (!info->joined_stw) {
3406 SGEN_LOG (3, "Skipping thread not seen in STW %p, range: %p-%p, size: %td", info, info->stack_start, info->stack_end, (char*)info->stack_end - (char*)info->stack_start);
3410 SGEN_LOG (3, "Scanning thread %p, range: %p-%p, size: %td, pinned=%d", info, info->stack_start, info->stack_end, (char*)info->stack_end - (char*)info->stack_start, sgen_get_pinned_count ());
3411 if (!info->thread_is_dying) {
3412 if (gc_callbacks.thread_mark_func && !conservative_stack_mark) {
3413 UserCopyOrMarkData data = { NULL, queue };
3414 set_user_copy_or_mark_data (&data);
3415 gc_callbacks.thread_mark_func (info->runtime_data, info->stack_start, info->stack_end, precise);
3416 set_user_copy_or_mark_data (NULL);
3417 } else if (!precise) {
3418 conservatively_pin_objects_from (info->stack_start, info->stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
3422 if (!info->thread_is_dying && !precise) {
3424 conservatively_pin_objects_from ((void**)&info->ctx, (void**)&info->ctx + ARCH_NUM_REGS,
3425 start_nursery, end_nursery, PIN_TYPE_STACK);
3427 conservatively_pin_objects_from (&info->regs, &info->regs + ARCH_NUM_REGS,
3428 start_nursery, end_nursery, PIN_TYPE_STACK);
3431 } END_FOREACH_THREAD
3435 ptr_on_stack (void *ptr)
3437 gpointer stack_start = &stack_start;
3438 SgenThreadInfo *info = mono_thread_info_current ();
3440 if (ptr >= stack_start && ptr < (gpointer)info->stack_end)
3446 sgen_thread_register (SgenThreadInfo* info, void *addr)
3448 #ifndef HAVE_KW_THREAD
3449 SgenThreadInfo *__thread_info__ = info;
3453 #ifndef HAVE_KW_THREAD
3454 info->tlab_start = info->tlab_next = info->tlab_temp_end = info->tlab_real_end = NULL;
3456 g_assert (!mono_native_tls_get_value (thread_info_key));
3457 mono_native_tls_set_value (thread_info_key, info);
3459 sgen_thread_info = info;
3462 #if !defined(__MACH__)
3463 info->stop_count = -1;
3467 info->joined_stw = FALSE;
3468 info->doing_handshake = FALSE;
3469 info->thread_is_dying = FALSE;
3470 info->stack_start = NULL;
3471 info->store_remset_buffer_addr = &STORE_REMSET_BUFFER;
3472 info->store_remset_buffer_index_addr = &STORE_REMSET_BUFFER_INDEX;
3473 info->stopped_ip = NULL;
3474 info->stopped_domain = NULL;
3476 memset (&info->ctx, 0, sizeof (MonoContext));
3478 memset (&info->regs, 0, sizeof (info->regs));
3481 sgen_init_tlab_info (info);
3483 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
3485 #ifdef HAVE_KW_THREAD
3486 store_remset_buffer_index_addr = &store_remset_buffer_index;
3489 /* try to get it with attributes first */
3490 #if defined(HAVE_PTHREAD_GETATTR_NP) && defined(HAVE_PTHREAD_ATTR_GETSTACK)
3494 pthread_attr_t attr;
3495 pthread_getattr_np (pthread_self (), &attr);
3496 pthread_attr_getstack (&attr, &sstart, &size);
3497 info->stack_start_limit = sstart;
3498 info->stack_end = (char*)sstart + size;
3499 pthread_attr_destroy (&attr);
3501 #elif defined(HAVE_PTHREAD_GET_STACKSIZE_NP) && defined(HAVE_PTHREAD_GET_STACKADDR_NP)
3502 info->stack_end = (char*)pthread_get_stackaddr_np (pthread_self ());
3503 info->stack_start_limit = (char*)info->stack_end - pthread_get_stacksize_np (pthread_self ());
3506 /* FIXME: we assume the stack grows down */
3507 gsize stack_bottom = (gsize)addr;
3508 stack_bottom += 4095;
3509 stack_bottom &= ~4095;
3510 info->stack_end = (char*)stack_bottom;
3514 #ifdef HAVE_KW_THREAD
3515 stack_end = info->stack_end;
3518 if (remset.register_thread)
3519 remset.register_thread (info);
3521 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->stack_end);
3523 if (gc_callbacks.thread_attach_func)
3524 info->runtime_data = gc_callbacks.thread_attach_func ();
3531 sgen_wbarrier_cleanup_thread (SgenThreadInfo *p)
3533 if (remset.cleanup_thread)
3534 remset.cleanup_thread (p);
3538 sgen_thread_unregister (SgenThreadInfo *p)
3540 /* If a delegate is passed to native code and invoked on a thread we dont
3541 * know about, the jit will register it with mono_jit_thread_attach, but
3542 * we have no way of knowing when that thread goes away. SGen has a TSD
3543 * so we assume that if the domain is still registered, we can detach
3546 if (mono_domain_get ())
3547 mono_thread_detach (mono_thread_current ());
3549 p->thread_is_dying = TRUE;
3552 There is a race condition between a thread finishing executing and been removed
3553 from the GC thread set.
3554 This happens on posix systems when TLS data is been cleaned-up, libpthread will
3555 set the thread_info slot to NULL before calling the cleanup function. This
3556 opens a window in which the thread is registered but has a NULL TLS.
3558 The suspend signal handler needs TLS data to know where to store thread state
3559 data or otherwise it will simply ignore the thread.
3561 This solution works because the thread doing STW will wait until all threads been
3562 suspended handshake back, so there is no race between the doing_hankshake test
3563 and the suspend_thread call.
3565 This is not required on systems that do synchronous STW as those can deal with
3566 the above race at suspend time.
3568 FIXME: I believe we could avoid this by using mono_thread_info_lookup when
3569 mono_thread_info_current returns NULL. Or fix mono_thread_info_lookup to do so.
3571 #if (defined(__MACH__) && MONO_MACH_ARCH_SUPPORTED) || !defined(HAVE_PTHREAD_KILL)
3574 while (!TRYLOCK_GC) {
3575 if (!sgen_park_current_thread_if_doing_handshake (p))
3581 binary_protocol_thread_unregister ((gpointer)mono_thread_info_get_tid (p));
3582 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)mono_thread_info_get_tid (p));
3584 if (gc_callbacks.thread_detach_func) {
3585 gc_callbacks.thread_detach_func (p->runtime_data);
3586 p->runtime_data = NULL;
3588 sgen_wbarrier_cleanup_thread (p);
3590 mono_threads_unregister_current_thread (p);
3596 sgen_thread_attach (SgenThreadInfo *info)
3599 /*this is odd, can we get attached before the gc is inited?*/
3603 if (gc_callbacks.thread_attach_func && !info->runtime_data)
3604 info->runtime_data = gc_callbacks.thread_attach_func ();
3607 mono_gc_register_thread (void *baseptr)
3609 return mono_thread_info_attach (baseptr) != NULL;
3613 * mono_gc_set_stack_end:
3615 * Set the end of the current threads stack to STACK_END. The stack space between
3616 * STACK_END and the real end of the threads stack will not be scanned during collections.
3619 mono_gc_set_stack_end (void *stack_end)
3621 SgenThreadInfo *info;
3624 info = mono_thread_info_current ();
3626 g_assert (stack_end < info->stack_end);
3627 info->stack_end = stack_end;
3632 #if USE_PTHREAD_INTERCEPT
3636 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
3638 return pthread_create (new_thread, attr, start_routine, arg);
3642 mono_gc_pthread_join (pthread_t thread, void **retval)
3644 return pthread_join (thread, retval);
3648 mono_gc_pthread_detach (pthread_t thread)
3650 return pthread_detach (thread);
3654 mono_gc_pthread_exit (void *retval)
3656 pthread_exit (retval);
3659 #endif /* USE_PTHREAD_INTERCEPT */
3662 * ######################################################################
3663 * ######## Write barriers
3664 * ######################################################################
3668 * Note: the write barriers first do the needed GC work and then do the actual store:
3669 * this way the value is visible to the conservative GC scan after the write barrier
3670 * itself. If a GC interrupts the barrier in the middle, value will be kept alive by
3671 * the conservative scan, otherwise by the remembered set scan.
3674 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
3676 HEAVY_STAT (++stat_wbarrier_set_field);
3677 if (ptr_in_nursery (field_ptr)) {
3678 *(void**)field_ptr = value;
3681 SGEN_LOG (8, "Adding remset at %p", field_ptr);
3683 binary_protocol_wbarrier (field_ptr, value, value->vtable);
3685 remset.wbarrier_set_field (obj, field_ptr, value);
3689 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
3691 HEAVY_STAT (++stat_wbarrier_set_arrayref);
3692 if (ptr_in_nursery (slot_ptr)) {
3693 *(void**)slot_ptr = value;
3696 SGEN_LOG (8, "Adding remset at %p", slot_ptr);
3698 binary_protocol_wbarrier (slot_ptr, value, value->vtable);
3700 remset.wbarrier_set_arrayref (arr, slot_ptr, value);
3704 mono_gc_wbarrier_arrayref_copy (gpointer dest_ptr, gpointer src_ptr, int count)
3706 HEAVY_STAT (++stat_wbarrier_arrayref_copy);
3707 /*This check can be done without taking a lock since dest_ptr array is pinned*/
3708 if (ptr_in_nursery (dest_ptr) || count <= 0) {
3709 mono_gc_memmove (dest_ptr, src_ptr, count * sizeof (gpointer));
3713 #ifdef SGEN_BINARY_PROTOCOL
3716 for (i = 0; i < count; ++i) {
3717 gpointer dest = (gpointer*)dest_ptr + i;
3718 gpointer obj = *((gpointer*)src_ptr + i);
3720 binary_protocol_wbarrier (dest, obj, (gpointer)LOAD_VTABLE (obj));
3725 remset.wbarrier_arrayref_copy (dest_ptr, src_ptr, count);
3728 static char *found_obj;
3731 find_object_for_ptr_callback (char *obj, size_t size, void *user_data)
3733 char *ptr = user_data;
3735 if (ptr >= obj && ptr < obj + size) {
3736 g_assert (!found_obj);
3741 /* for use in the debugger */
3742 char* find_object_for_ptr (char *ptr);
3744 find_object_for_ptr (char *ptr)
3746 if (ptr >= nursery_section->data && ptr < nursery_section->end_data) {
3748 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
3749 find_object_for_ptr_callback, ptr, TRUE);
3755 sgen_los_iterate_objects (find_object_for_ptr_callback, ptr);
3760 * Very inefficient, but this is debugging code, supposed to
3761 * be called from gdb, so we don't care.
3764 major_collector.iterate_objects (TRUE, TRUE, find_object_for_ptr_callback, ptr);
3769 mono_gc_wbarrier_generic_nostore (gpointer ptr)
3771 HEAVY_STAT (++stat_wbarrier_generic_store);
3773 #ifdef XDOMAIN_CHECKS_IN_WBARRIER
3774 /* FIXME: ptr_in_heap must be called with the GC lock held */
3775 if (xdomain_checks && *(MonoObject**)ptr && ptr_in_heap (ptr)) {
3776 char *start = find_object_for_ptr (ptr);
3777 MonoObject *value = *(MonoObject**)ptr;
3781 MonoObject *obj = (MonoObject*)start;
3782 if (obj->vtable->domain != value->vtable->domain)
3783 g_assert (is_xdomain_ref_allowed (ptr, start, obj->vtable->domain));
3789 if (*(gpointer*)ptr)
3790 binary_protocol_wbarrier (ptr, *(gpointer*)ptr, (gpointer)LOAD_VTABLE (*(gpointer*)ptr));
3792 if (ptr_in_nursery (ptr) || ptr_on_stack (ptr) || !ptr_in_nursery (*(gpointer*)ptr)) {
3793 SGEN_LOG (8, "Skipping remset at %p", ptr);
3797 SGEN_LOG (8, "Adding remset at %p", ptr);
3799 remset.wbarrier_generic_nostore (ptr);
3803 mono_gc_wbarrier_generic_store (gpointer ptr, MonoObject* value)
3805 SGEN_LOG (8, "Wbarrier store at %p to %p (%s)", ptr, value, value ? safe_name (value) : "null");
3806 *(void**)ptr = value;
3807 if (ptr_in_nursery (value))
3808 mono_gc_wbarrier_generic_nostore (ptr);
3809 sgen_dummy_use (value);
3812 void mono_gc_wbarrier_value_copy_bitmap (gpointer _dest, gpointer _src, int size, unsigned bitmap)
3814 mword *dest = _dest;
3819 mono_gc_wbarrier_generic_store (dest, (MonoObject*)*src);
3824 size -= SIZEOF_VOID_P;
3829 #ifdef SGEN_BINARY_PROTOCOL
3831 #define HANDLE_PTR(ptr,obj) do { \
3832 gpointer o = *(gpointer*)(ptr); \
3834 gpointer d = ((char*)dest) + ((char*)(ptr) - (char*)(obj)); \
3835 binary_protocol_wbarrier (d, o, (gpointer) LOAD_VTABLE (o)); \
3840 scan_object_for_binary_protocol_copy_wbarrier (gpointer dest, char *start, mword desc)
3842 #define SCAN_OBJECT_NOVTABLE
3843 #include "sgen-scan-object.h"
3848 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
3850 HEAVY_STAT (++stat_wbarrier_value_copy);
3851 g_assert (klass->valuetype);
3853 SGEN_LOG (8, "Adding value remset at %p, count %d, descr %p for class %s (%p)", dest, count, klass->gc_descr, klass->name, klass);
3855 if (ptr_in_nursery (dest) || ptr_on_stack (dest) || !SGEN_CLASS_HAS_REFERENCES (klass)) {
3856 size_t element_size = mono_class_value_size (klass, NULL);
3857 size_t size = count * element_size;
3858 mono_gc_memmove (dest, src, size);
3862 #ifdef SGEN_BINARY_PROTOCOL
3864 size_t element_size = mono_class_value_size (klass, NULL);
3866 for (i = 0; i < count; ++i) {
3867 scan_object_for_binary_protocol_copy_wbarrier ((char*)dest + i * element_size,
3868 (char*)src + i * element_size - sizeof (MonoObject),
3869 (mword) klass->gc_descr);
3874 remset.wbarrier_value_copy (dest, src, count, klass);
3878 * mono_gc_wbarrier_object_copy:
3880 * Write barrier to call when obj is the result of a clone or copy of an object.
3883 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
3887 HEAVY_STAT (++stat_wbarrier_object_copy);
3889 if (ptr_in_nursery (obj) || ptr_on_stack (obj)) {
3890 size = mono_object_class (obj)->instance_size;
3891 mono_gc_memmove ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
3892 size - sizeof (MonoObject));
3896 #ifdef SGEN_BINARY_PROTOCOL
3897 scan_object_for_binary_protocol_copy_wbarrier (obj, (char*)src, (mword) src->vtable->gc_descr);
3900 remset.wbarrier_object_copy (obj, src);
3905 * ######################################################################
3906 * ######## Other mono public interface functions.
3907 * ######################################################################
3910 #define REFS_SIZE 128
3913 MonoGCReferences callback;
3917 MonoObject *refs [REFS_SIZE];
3918 uintptr_t offsets [REFS_SIZE];
3922 #define HANDLE_PTR(ptr,obj) do { \
3924 if (hwi->count == REFS_SIZE) { \
3925 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
3929 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
3930 hwi->refs [hwi->count++] = *(ptr); \
3935 collect_references (HeapWalkInfo *hwi, char *start, size_t size)
3937 #include "sgen-scan-object.h"
3941 walk_references (char *start, size_t size, void *data)
3943 HeapWalkInfo *hwi = data;
3946 collect_references (hwi, start, size);
3947 if (hwi->count || !hwi->called)
3948 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
3952 * mono_gc_walk_heap:
3953 * @flags: flags for future use
3954 * @callback: a function pointer called for each object in the heap
3955 * @data: a user data pointer that is passed to callback
3957 * This function can be used to iterate over all the live objects in the heap:
3958 * for each object, @callback is invoked, providing info about the object's
3959 * location in memory, its class, its size and the objects it references.
3960 * For each referenced object it's offset from the object address is
3961 * reported in the offsets array.
3962 * The object references may be buffered, so the callback may be invoked
3963 * multiple times for the same object: in all but the first call, the size
3964 * argument will be zero.
3965 * Note that this function can be only called in the #MONO_GC_EVENT_PRE_START_WORLD
3966 * profiler event handler.
3968 * Returns: a non-zero value if the GC doesn't support heap walking
3971 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
3976 hwi.callback = callback;
3979 sgen_clear_nursery_fragments ();
3980 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE);
3982 major_collector.iterate_objects (TRUE, TRUE, walk_references, &hwi);
3983 sgen_los_iterate_objects (walk_references, &hwi);
3989 mono_gc_collect (int generation)
3994 sgen_perform_collection (0, generation, "user request");
3999 mono_gc_max_generation (void)
4005 mono_gc_collection_count (int generation)
4007 if (generation == 0)
4008 return stat_minor_gcs;
4009 return stat_major_gcs;
4013 mono_gc_get_used_size (void)
4017 tot = los_memory_usage;
4018 tot += nursery_section->next_data - nursery_section->data;
4019 tot += major_collector.get_used_size ();
4020 /* FIXME: account for pinned objects */
4026 mono_gc_disable (void)
4034 mono_gc_enable (void)
4042 mono_gc_get_los_limit (void)
4044 return MAX_SMALL_OBJ_SIZE;
4048 mono_gc_user_markers_supported (void)
4054 mono_object_is_alive (MonoObject* o)
4060 mono_gc_get_generation (MonoObject *obj)
4062 if (ptr_in_nursery (obj))
4068 mono_gc_enable_events (void)
4073 mono_gc_weak_link_add (void **link_addr, MonoObject *obj, gboolean track)
4075 sgen_register_disappearing_link (obj, link_addr, track, FALSE);
4079 mono_gc_weak_link_remove (void **link_addr)
4081 sgen_register_disappearing_link (NULL, link_addr, FALSE, FALSE);
4085 mono_gc_weak_link_get (void **link_addr)
4088 * We must only load *link_addr once because it might change
4089 * under our feet, and REVEAL_POINTER (NULL) results in an
4090 * invalid reference.
4092 void *ptr = *link_addr;
4097 * During the second bridge processing step the world is
4098 * running again. That step processes all weak links once
4099 * more to null those that refer to dead objects. Before that
4100 * is completed, those links must not be followed, so we
4101 * conservatively wait for bridge processing when any weak
4102 * link is dereferenced.
4104 if (G_UNLIKELY (bridge_processing_in_progress))
4105 mono_gc_wait_for_bridge_processing ();
4107 return (MonoObject*) REVEAL_POINTER (ptr);
4111 mono_gc_ephemeron_array_add (MonoObject *obj)
4113 EphemeronLinkNode *node;
4117 node = sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
4122 node->array = (char*)obj;
4123 node->next = ephemeron_list;
4124 ephemeron_list = node;
4126 SGEN_LOG (5, "Registered ephemeron array %p", obj);
4133 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
4137 result = func (data);
4138 UNLOCK_INTERRUPTION;
4143 mono_gc_is_gc_thread (void)
4147 result = mono_thread_info_current () != NULL;
4153 is_critical_method (MonoMethod *method)
4155 return mono_runtime_is_critical_method (method) || sgen_is_critical_method (method);
4159 mono_gc_base_init (void)
4161 MonoThreadInfoCallbacks cb;
4164 char *major_collector_opt = NULL;
4165 char *minor_collector_opt = NULL;
4167 glong soft_limit = 0;
4171 gboolean debug_print_allowance = FALSE;
4172 double allowance_ratio = 0, save_target = 0;
4175 result = InterlockedCompareExchange (&gc_initialized, -1, 0);
4178 /* already inited */
4181 /* being inited by another thread */
4185 /* we will init it */
4188 g_assert_not_reached ();
4190 } while (result != 0);
4192 LOCK_INIT (gc_mutex);
4194 pagesize = mono_pagesize ();
4195 gc_debug_file = stderr;
4197 cb.thread_register = sgen_thread_register;
4198 cb.thread_unregister = sgen_thread_unregister;
4199 cb.thread_attach = sgen_thread_attach;
4200 cb.mono_method_is_critical = (gpointer)is_critical_method;
4202 cb.mono_gc_pthread_create = (gpointer)mono_gc_pthread_create;
4205 mono_threads_init (&cb, sizeof (SgenThreadInfo));
4207 LOCK_INIT (sgen_interruption_mutex);
4208 LOCK_INIT (pin_queue_mutex);
4210 init_user_copy_or_mark_key ();
4212 if ((env = getenv ("MONO_GC_PARAMS"))) {
4213 opts = g_strsplit (env, ",", -1);
4214 for (ptr = opts; *ptr; ++ptr) {
4216 if (g_str_has_prefix (opt, "major=")) {
4217 opt = strchr (opt, '=') + 1;
4218 major_collector_opt = g_strdup (opt);
4219 } else if (g_str_has_prefix (opt, "minor=")) {
4220 opt = strchr (opt, '=') + 1;
4221 minor_collector_opt = g_strdup (opt);
4229 sgen_init_internal_allocator ();
4230 sgen_init_nursery_allocator ();
4232 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_SECTION, SGEN_SIZEOF_GC_MEM_SECTION);
4233 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_FINALIZE_READY_ENTRY, sizeof (FinalizeReadyEntry));
4234 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_GRAY_QUEUE, sizeof (GrayQueueSection));
4235 g_assert (sizeof (GenericStoreRememberedSet) == sizeof (gpointer) * STORE_REMSET_BUFFER_SIZE);
4236 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_STORE_REMSET, sizeof (GenericStoreRememberedSet));
4237 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
4239 #ifndef HAVE_KW_THREAD
4240 mono_native_tls_alloc (&thread_info_key, NULL);
4244 * This needs to happen before any internal allocations because
4245 * it inits the small id which is required for hazard pointer
4250 mono_thread_info_attach (&dummy);
4252 if (!minor_collector_opt) {
4253 sgen_simple_nursery_init (&sgen_minor_collector);
4255 if (!strcmp (minor_collector_opt, "simple"))
4256 sgen_simple_nursery_init (&sgen_minor_collector);
4257 else if (!strcmp (minor_collector_opt, "split"))
4258 sgen_split_nursery_init (&sgen_minor_collector);
4260 fprintf (stderr, "Unknown minor collector `%s'.\n", minor_collector_opt);
4265 if (!major_collector_opt || !strcmp (major_collector_opt, "marksweep")) {
4266 sgen_marksweep_init (&major_collector);
4267 } else if (!major_collector_opt || !strcmp (major_collector_opt, "marksweep-fixed")) {
4268 sgen_marksweep_fixed_init (&major_collector);
4269 } else if (!major_collector_opt || !strcmp (major_collector_opt, "marksweep-par")) {
4270 sgen_marksweep_par_init (&major_collector);
4271 } else if (!major_collector_opt || !strcmp (major_collector_opt, "marksweep-fixed-par")) {
4272 sgen_marksweep_fixed_par_init (&major_collector);
4273 } else if (!strcmp (major_collector_opt, "copying")) {
4274 sgen_copying_init (&major_collector);
4276 fprintf (stderr, "Unknown major collector `%s'.\n", major_collector_opt);
4280 #ifdef SGEN_HAVE_CARDTABLE
4281 use_cardtable = major_collector.supports_cardtable;
4283 use_cardtable = FALSE;
4286 num_workers = mono_cpu_count ();
4287 g_assert (num_workers > 0);
4288 if (num_workers > 16)
4291 ///* Keep this the default for now */
4292 /* Precise marking is broken on all supported targets. Disable until fixed. */
4293 conservative_stack_mark = TRUE;
4295 sgen_nursery_size = DEFAULT_NURSERY_SIZE;
4298 for (ptr = opts; *ptr; ++ptr) {
4300 if (g_str_has_prefix (opt, "major="))
4302 if (g_str_has_prefix (opt, "minor="))
4304 if (g_str_has_prefix (opt, "wbarrier=")) {
4305 opt = strchr (opt, '=') + 1;
4306 if (strcmp (opt, "remset") == 0) {
4307 use_cardtable = FALSE;
4308 } else if (strcmp (opt, "cardtable") == 0) {
4309 if (!use_cardtable) {
4310 if (major_collector.supports_cardtable)
4311 fprintf (stderr, "The cardtable write barrier is not supported on this platform.\n");
4313 fprintf (stderr, "The major collector does not support the cardtable write barrier.\n");
4317 fprintf (stderr, "wbarrier must either be `remset' or `cardtable'.");
4322 if (g_str_has_prefix (opt, "max-heap-size=")) {
4323 opt = strchr (opt, '=') + 1;
4324 if (*opt && mono_gc_parse_environment_string_extract_number (opt, &max_heap)) {
4325 if ((max_heap & (mono_pagesize () - 1))) {
4326 fprintf (stderr, "max-heap-size size must be a multiple of %d.\n", mono_pagesize ());
4330 fprintf (stderr, "max-heap-size must be an integer.\n");
4335 if (g_str_has_prefix (opt, "soft-heap-limit=")) {
4336 opt = strchr (opt, '=') + 1;
4337 if (*opt && mono_gc_parse_environment_string_extract_number (opt, &soft_limit)) {
4338 if (soft_limit <= 0) {
4339 fprintf (stderr, "soft-heap-limit must be positive.\n");
4343 fprintf (stderr, "soft-heap-limit must be an integer.\n");
4348 if (g_str_has_prefix (opt, "workers=")) {
4351 if (!major_collector.is_parallel) {
4352 fprintf (stderr, "The workers= option can only be used for parallel collectors.");
4355 opt = strchr (opt, '=') + 1;
4356 val = strtol (opt, &endptr, 10);
4357 if (!*opt || *endptr) {
4358 fprintf (stderr, "Cannot parse the workers= option value.");
4361 if (val <= 0 || val > 16) {
4362 fprintf (stderr, "The number of workers must be in the range 1 to 16.");
4365 num_workers = (int)val;
4368 if (g_str_has_prefix (opt, "stack-mark=")) {
4369 opt = strchr (opt, '=') + 1;
4370 if (!strcmp (opt, "precise")) {
4371 conservative_stack_mark = FALSE;
4372 } else if (!strcmp (opt, "conservative")) {
4373 conservative_stack_mark = TRUE;
4375 fprintf (stderr, "Invalid value '%s' for stack-mark= option, possible values are: 'precise', 'conservative'.\n", opt);
4380 if (g_str_has_prefix (opt, "bridge=")) {
4381 opt = strchr (opt, '=') + 1;
4382 sgen_register_test_bridge_callbacks (g_strdup (opt));
4386 if (g_str_has_prefix (opt, "nursery-size=")) {
4388 opt = strchr (opt, '=') + 1;
4389 if (*opt && mono_gc_parse_environment_string_extract_number (opt, &val)) {
4390 sgen_nursery_size = val;
4391 #ifdef SGEN_ALIGN_NURSERY
4392 if ((val & (val - 1))) {
4393 fprintf (stderr, "The nursery size must be a power of two.\n");
4397 if (val < SGEN_MAX_NURSERY_WASTE) {
4398 fprintf (stderr, "The nursery size must be at least %d bytes.\n", SGEN_MAX_NURSERY_WASTE);
4402 sgen_nursery_bits = 0;
4403 while (1 << (++ sgen_nursery_bits) != sgen_nursery_size)
4407 fprintf (stderr, "nursery-size must be an integer.\n");
4413 if (g_str_has_prefix (opt, "save-target-ratio=")) {
4415 opt = strchr (opt, '=') + 1;
4416 save_target = strtod (opt, &endptr);
4417 if (endptr == opt) {
4418 fprintf (stderr, "save-target-ratio must be a number.");
4421 if (save_target < SGEN_MIN_SAVE_TARGET_RATIO || save_target > SGEN_MAX_SAVE_TARGET_RATIO) {
4422 fprintf (stderr, "save-target-ratio must be between %.2f - %.2f.", SGEN_MIN_SAVE_TARGET_RATIO, SGEN_MAX_SAVE_TARGET_RATIO);
4427 if (g_str_has_prefix (opt, "default-allowance-ratio=")) {
4429 opt = strchr (opt, '=') + 1;
4431 allowance_ratio = strtod (opt, &endptr);
4432 if (endptr == opt) {
4433 fprintf (stderr, "save-target-ratio must be a number.");
4436 if (allowance_ratio < SGEN_MIN_ALLOWANCE_NURSERY_SIZE_RATIO || allowance_ratio > SGEN_MIN_ALLOWANCE_NURSERY_SIZE_RATIO) {
4437 fprintf (stderr, "default-allowance-ratio must be between %.2f - %.2f.", SGEN_MIN_ALLOWANCE_NURSERY_SIZE_RATIO, SGEN_MIN_ALLOWANCE_NURSERY_SIZE_RATIO);
4443 if (major_collector.handle_gc_param && major_collector.handle_gc_param (opt))
4446 if (sgen_minor_collector.handle_gc_param && sgen_minor_collector.handle_gc_param (opt))
4449 fprintf (stderr, "MONO_GC_PARAMS must be a comma-delimited list of one or more of the following:\n");
4450 fprintf (stderr, " max-heap-size=N (where N is an integer, possibly with a k, m or a g suffix)\n");
4451 fprintf (stderr, " soft-heap-limit=n (where N is an integer, possibly with a k, m or a g suffix)\n");
4452 fprintf (stderr, " nursery-size=N (where N is an integer, possibly with a k, m or a g suffix)\n");
4453 fprintf (stderr, " major=COLLECTOR (where COLLECTOR is `marksweep', `marksweep-par', 'marksweep-fixed', 'marksweep-fixed-par' or `copying')\n");
4454 fprintf (stderr, " minor=COLLECTOR (where COLLECTOR is `simple' or `split')\n");
4455 fprintf (stderr, " wbarrier=WBARRIER (where WBARRIER is `remset' or `cardtable')\n");
4456 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
4457 if (major_collector.print_gc_param_usage)
4458 major_collector.print_gc_param_usage ();
4459 if (sgen_minor_collector.print_gc_param_usage)
4460 sgen_minor_collector.print_gc_param_usage ();
4461 fprintf (stderr, " Experimental options:\n");
4462 fprintf (stderr, " save-target-ratio=R (where R must be between %.2f - %.2f).\n", SGEN_MIN_SAVE_TARGET_RATIO, SGEN_MAX_SAVE_TARGET_RATIO);
4463 fprintf (stderr, " default-allowance-ratio=R (where R must be between %.2f - %.2f).\n", SGEN_MIN_ALLOWANCE_NURSERY_SIZE_RATIO, SGEN_MAX_ALLOWANCE_NURSERY_SIZE_RATIO);
4469 if (major_collector.is_parallel)
4470 sgen_workers_init (num_workers);
4472 if (major_collector_opt)
4473 g_free (major_collector_opt);
4475 if (minor_collector_opt)
4476 g_free (minor_collector_opt);
4480 if ((env = getenv ("MONO_GC_DEBUG"))) {
4481 opts = g_strsplit (env, ",", -1);
4482 for (ptr = opts; ptr && *ptr; ptr ++) {
4484 if (opt [0] >= '0' && opt [0] <= '9') {
4485 gc_debug_level = atoi (opt);
4491 char *rf = g_strdup_printf ("%s.%d", opt, GetCurrentProcessId ());
4493 char *rf = g_strdup_printf ("%s.%d", opt, getpid ());
4495 gc_debug_file = fopen (rf, "wb");
4497 gc_debug_file = stderr;
4500 } else if (!strcmp (opt, "print-allowance")) {
4501 debug_print_allowance = TRUE;
4502 } else if (!strcmp (opt, "print-pinning")) {
4503 do_pin_stats = TRUE;
4504 } else if (!strcmp (opt, "verify-before-allocs")) {
4505 verify_before_allocs = 1;
4506 has_per_allocation_action = TRUE;
4507 } else if (g_str_has_prefix (opt, "verify-before-allocs=")) {
4508 char *arg = strchr (opt, '=') + 1;
4509 verify_before_allocs = atoi (arg);
4510 has_per_allocation_action = TRUE;
4511 } else if (!strcmp (opt, "collect-before-allocs")) {
4512 collect_before_allocs = 1;
4513 has_per_allocation_action = TRUE;
4514 } else if (g_str_has_prefix (opt, "collect-before-allocs=")) {
4515 char *arg = strchr (opt, '=') + 1;
4516 has_per_allocation_action = TRUE;
4517 collect_before_allocs = atoi (arg);
4518 } else if (!strcmp (opt, "verify-before-collections")) {
4519 whole_heap_check_before_collection = TRUE;
4520 } else if (!strcmp (opt, "check-at-minor-collections")) {
4521 consistency_check_at_minor_collection = TRUE;
4522 nursery_clear_policy = CLEAR_AT_GC;
4523 } else if (!strcmp (opt, "xdomain-checks")) {
4524 xdomain_checks = TRUE;
4525 } else if (!strcmp (opt, "clear-at-gc")) {
4526 nursery_clear_policy = CLEAR_AT_GC;
4527 } else if (!strcmp (opt, "clear-nursery-at-gc")) {
4528 nursery_clear_policy = CLEAR_AT_GC;
4529 } else if (!strcmp (opt, "check-scan-starts")) {
4530 do_scan_starts_check = TRUE;
4531 } else if (!strcmp (opt, "verify-nursery-at-minor-gc")) {
4532 do_verify_nursery = TRUE;
4533 } else if (!strcmp (opt, "dump-nursery-at-minor-gc")) {
4534 do_dump_nursery_content = TRUE;
4535 } else if (!strcmp (opt, "no-managed-allocator")) {
4536 sgen_set_use_managed_allocator (FALSE);
4537 } else if (!strcmp (opt, "disable-minor")) {
4538 disable_minor_collections = TRUE;
4539 } else if (!strcmp (opt, "disable-major")) {
4540 disable_major_collections = TRUE;
4541 } else if (g_str_has_prefix (opt, "heap-dump=")) {
4542 char *filename = strchr (opt, '=') + 1;
4543 nursery_clear_policy = CLEAR_AT_GC;
4544 heap_dump_file = fopen (filename, "w");
4545 if (heap_dump_file) {
4546 fprintf (heap_dump_file, "<sgen-dump>\n");
4547 do_pin_stats = TRUE;
4549 #ifdef SGEN_BINARY_PROTOCOL
4550 } else if (g_str_has_prefix (opt, "binary-protocol=")) {
4551 char *filename = strchr (opt, '=') + 1;
4552 binary_protocol_init (filename);
4554 fprintf (stderr, "Warning: Cardtable write barriers will not be binary-protocolled.\n");
4557 fprintf (stderr, "Invalid format for the MONO_GC_DEBUG env variable: '%s'\n", env);
4558 fprintf (stderr, "The format is: MONO_GC_DEBUG=[l[:filename]|<option>]+ where l is a debug level 0-9.\n");
4559 fprintf (stderr, "Valid options are:\n");
4560 fprintf (stderr, " collect-before-allocs[=<n>]\n");
4561 fprintf (stderr, " verify-before-allocs[=<n>]\n");
4562 fprintf (stderr, " check-at-minor-collections\n");
4563 fprintf (stderr, " verify-before-collections\n");
4564 fprintf (stderr, " verify-nursery-at-minor-gc\n");
4565 fprintf (stderr, " dump-nursery-at-minor-gc\n");
4566 fprintf (stderr, " disable-minor\n");
4567 fprintf (stderr, " disable-major\n");
4568 fprintf (stderr, " xdomain-checks\n");
4569 fprintf (stderr, " clear-at-gc\n");
4570 fprintf (stderr, " clear-nursery-at-gc\n");
4571 fprintf (stderr, " check-scan-starts\n");
4572 fprintf (stderr, " no-managed-allocator\n");
4573 fprintf (stderr, " print-allowance\n");
4574 fprintf (stderr, " print-pinning\n");
4575 fprintf (stderr, " heap-dump=<filename>\n");
4576 #ifdef SGEN_BINARY_PROTOCOL
4577 fprintf (stderr, " binary-protocol=<filename>\n");
4585 if (major_collector.is_parallel) {
4586 if (heap_dump_file) {
4587 fprintf (stderr, "Error: Cannot do heap dump with the parallel collector.\n");
4591 fprintf (stderr, "Error: Cannot gather pinning statistics with the parallel collector.\n");
4596 if (major_collector.post_param_init)
4597 major_collector.post_param_init ();
4599 sgen_memgov_init (max_heap, soft_limit, debug_print_allowance, allowance_ratio, save_target);
4601 memset (&remset, 0, sizeof (remset));
4603 #ifdef SGEN_HAVE_CARDTABLE
4605 sgen_card_table_init (&remset);
4608 sgen_ssb_init (&remset);
4610 if (remset.register_thread)
4611 remset.register_thread (mono_thread_info_current ());
4617 mono_gc_get_gc_name (void)
4622 static MonoMethod *write_barrier_method;
4625 sgen_is_critical_method (MonoMethod *method)
4627 return (method == write_barrier_method || sgen_is_managed_allocator (method));
4631 sgen_has_critical_method (void)
4633 return write_barrier_method || sgen_has_managed_allocator ();
4637 emit_nursery_check (MonoMethodBuilder *mb, int *nursery_check_return_labels)
4639 memset (nursery_check_return_labels, 0, sizeof (int) * 3);
4640 #ifdef SGEN_ALIGN_NURSERY
4641 // if (ptr_in_nursery (ptr)) return;
4643 * Masking out the bits might be faster, but we would have to use 64 bit
4644 * immediates, which might be slower.
4646 mono_mb_emit_ldarg (mb, 0);
4647 mono_mb_emit_icon (mb, DEFAULT_NURSERY_BITS);
4648 mono_mb_emit_byte (mb, CEE_SHR_UN);
4649 mono_mb_emit_icon (mb, (mword)sgen_get_nursery_start () >> DEFAULT_NURSERY_BITS);
4650 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BEQ);
4652 // if (!ptr_in_nursery (*ptr)) return;
4653 mono_mb_emit_ldarg (mb, 0);
4654 mono_mb_emit_byte (mb, CEE_LDIND_I);
4655 mono_mb_emit_icon (mb, DEFAULT_NURSERY_BITS);
4656 mono_mb_emit_byte (mb, CEE_SHR_UN);
4657 mono_mb_emit_icon (mb, (mword)sgen_get_nursery_start () >> DEFAULT_NURSERY_BITS);
4658 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BNE_UN);
4660 int label_continue1, label_continue2;
4661 int dereferenced_var;
4663 // if (ptr < (sgen_get_nursery_start ())) goto continue;
4664 mono_mb_emit_ldarg (mb, 0);
4665 mono_mb_emit_ptr (mb, (gpointer) sgen_get_nursery_start ());
4666 label_continue_1 = mono_mb_emit_branch (mb, CEE_BLT);
4668 // if (ptr >= sgen_get_nursery_end ())) goto continue;
4669 mono_mb_emit_ldarg (mb, 0);
4670 mono_mb_emit_ptr (mb, (gpointer) sgen_get_nursery_end ());
4671 label_continue_2 = mono_mb_emit_branch (mb, CEE_BGE);
4674 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BR);
4677 mono_mb_patch_branch (mb, label_continue_1);
4678 mono_mb_patch_branch (mb, label_continue_2);
4680 // Dereference and store in local var
4681 dereferenced_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
4682 mono_mb_emit_ldarg (mb, 0);
4683 mono_mb_emit_byte (mb, CEE_LDIND_I);
4684 mono_mb_emit_stloc (mb, dereferenced_var);
4686 // if (*ptr < sgen_get_nursery_start ()) return;
4687 mono_mb_emit_ldloc (mb, dereferenced_var);
4688 mono_mb_emit_ptr (mb, (gpointer) sgen_get_nursery_start ());
4689 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BLT);
4691 // if (*ptr >= sgen_get_nursery_end ()) return;
4692 mono_mb_emit_ldloc (mb, dereferenced_var);
4693 mono_mb_emit_ptr (mb, (gpointer) sgen_get_nursery_end ());
4694 nursery_check_return_labels [2] = mono_mb_emit_branch (mb, CEE_BGE);
4699 mono_gc_get_write_barrier (void)
4702 MonoMethodBuilder *mb;
4703 MonoMethodSignature *sig;
4704 #ifdef MANAGED_WBARRIER
4705 int i, nursery_check_labels [3];
4706 int label_no_wb_3, label_no_wb_4, label_need_wb, label_slow_path;
4707 int buffer_var, buffer_index_var, dummy_var;
4709 #ifdef HAVE_KW_THREAD
4710 int stack_end_offset = -1, store_remset_buffer_offset = -1;
4711 int store_remset_buffer_index_offset = -1, store_remset_buffer_index_addr_offset = -1;
4713 MONO_THREAD_VAR_OFFSET (stack_end, stack_end_offset);
4714 g_assert (stack_end_offset != -1);
4715 MONO_THREAD_VAR_OFFSET (store_remset_buffer, store_remset_buffer_offset);
4716 g_assert (store_remset_buffer_offset != -1);
4717 MONO_THREAD_VAR_OFFSET (store_remset_buffer_index, store_remset_buffer_index_offset);
4718 g_assert (store_remset_buffer_index_offset != -1);
4719 MONO_THREAD_VAR_OFFSET (store_remset_buffer_index_addr, store_remset_buffer_index_addr_offset);
4720 g_assert (store_remset_buffer_index_addr_offset != -1);
4724 // FIXME: Maybe create a separate version for ctors (the branch would be
4725 // correctly predicted more times)
4726 if (write_barrier_method)
4727 return write_barrier_method;
4729 /* Create the IL version of mono_gc_barrier_generic_store () */
4730 sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
4731 sig->ret = &mono_defaults.void_class->byval_arg;
4732 sig->params [0] = &mono_defaults.int_class->byval_arg;
4734 mb = mono_mb_new (mono_defaults.object_class, "wbarrier", MONO_WRAPPER_WRITE_BARRIER);
4736 #ifdef MANAGED_WBARRIER
4737 if (use_cardtable) {
4738 emit_nursery_check (mb, nursery_check_labels);
4740 addr = sgen_cardtable + ((address >> CARD_BITS) & CARD_MASK)
4744 LDC_PTR sgen_cardtable
4746 address >> CARD_BITS
4750 if (SGEN_HAVE_OVERLAPPING_CARDS) {
4751 LDC_PTR card_table_mask
4758 mono_mb_emit_ptr (mb, sgen_cardtable);
4759 mono_mb_emit_ldarg (mb, 0);
4760 mono_mb_emit_icon (mb, CARD_BITS);
4761 mono_mb_emit_byte (mb, CEE_SHR_UN);
4762 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
4763 mono_mb_emit_ptr (mb, (gpointer)CARD_MASK);
4764 mono_mb_emit_byte (mb, CEE_AND);
4766 mono_mb_emit_byte (mb, CEE_ADD);
4767 mono_mb_emit_icon (mb, 1);
4768 mono_mb_emit_byte (mb, CEE_STIND_I1);
4771 for (i = 0; i < 3; ++i) {
4772 if (nursery_check_labels [i])
4773 mono_mb_patch_branch (mb, nursery_check_labels [i]);
4775 mono_mb_emit_byte (mb, CEE_RET);
4776 } else if (mono_runtime_has_tls_get ()) {
4777 emit_nursery_check (mb, nursery_check_labels);
4779 // if (ptr >= stack_end) goto need_wb;
4780 mono_mb_emit_ldarg (mb, 0);
4781 EMIT_TLS_ACCESS (mb, stack_end, stack_end_offset);
4782 label_need_wb = mono_mb_emit_branch (mb, CEE_BGE_UN);
4784 // if (ptr >= stack_start) return;
4785 dummy_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
4786 mono_mb_emit_ldarg (mb, 0);
4787 mono_mb_emit_ldloc_addr (mb, dummy_var);
4788 label_no_wb_3 = mono_mb_emit_branch (mb, CEE_BGE_UN);
4791 mono_mb_patch_branch (mb, label_need_wb);
4793 // buffer = STORE_REMSET_BUFFER;
4794 buffer_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
4795 EMIT_TLS_ACCESS (mb, store_remset_buffer, store_remset_buffer_offset);
4796 mono_mb_emit_stloc (mb, buffer_var);
4798 // buffer_index = STORE_REMSET_BUFFER_INDEX;
4799 buffer_index_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
4800 EMIT_TLS_ACCESS (mb, store_remset_buffer_index, store_remset_buffer_index_offset);
4801 mono_mb_emit_stloc (mb, buffer_index_var);
4803 // if (buffer [buffer_index] == ptr) return;
4804 mono_mb_emit_ldloc (mb, buffer_var);
4805 mono_mb_emit_ldloc (mb, buffer_index_var);
4806 g_assert (sizeof (gpointer) == 4 || sizeof (gpointer) == 8);
4807 mono_mb_emit_icon (mb, sizeof (gpointer) == 4 ? 2 : 3);
4808 mono_mb_emit_byte (mb, CEE_SHL);
4809 mono_mb_emit_byte (mb, CEE_ADD);
4810 mono_mb_emit_byte (mb, CEE_LDIND_I);
4811 mono_mb_emit_ldarg (mb, 0);
4812 label_no_wb_4 = mono_mb_emit_branch (mb, CEE_BEQ);
4815 mono_mb_emit_ldloc (mb, buffer_index_var);
4816 mono_mb_emit_icon (mb, 1);
4817 mono_mb_emit_byte (mb, CEE_ADD);
4818 mono_mb_emit_stloc (mb, buffer_index_var);
4820 // if (buffer_index >= STORE_REMSET_BUFFER_SIZE) goto slow_path;
4821 mono_mb_emit_ldloc (mb, buffer_index_var);
4822 mono_mb_emit_icon (mb, STORE_REMSET_BUFFER_SIZE);
4823 label_slow_path = mono_mb_emit_branch (mb, CEE_BGE);
4825 // buffer [buffer_index] = ptr;
4826 mono_mb_emit_ldloc (mb, buffer_var);
4827 mono_mb_emit_ldloc (mb, buffer_index_var);
4828 g_assert (sizeof (gpointer) == 4 || sizeof (gpointer) == 8);
4829 mono_mb_emit_icon (mb, sizeof (gpointer) == 4 ? 2 : 3);
4830 mono_mb_emit_byte (mb, CEE_SHL);
4831 mono_mb_emit_byte (mb, CEE_ADD);
4832 mono_mb_emit_ldarg (mb, 0);
4833 mono_mb_emit_byte (mb, CEE_STIND_I);
4835 // STORE_REMSET_BUFFER_INDEX = buffer_index;
4836 EMIT_TLS_ACCESS (mb, store_remset_buffer_index_addr, store_remset_buffer_index_addr_offset);
4837 mono_mb_emit_ldloc (mb, buffer_index_var);
4838 mono_mb_emit_byte (mb, CEE_STIND_I);
4841 for (i = 0; i < 3; ++i) {
4842 if (nursery_check_labels [i])
4843 mono_mb_patch_branch (mb, nursery_check_labels [i]);
4845 mono_mb_patch_branch (mb, label_no_wb_3);
4846 mono_mb_patch_branch (mb, label_no_wb_4);
4847 mono_mb_emit_byte (mb, CEE_RET);
4850 mono_mb_patch_branch (mb, label_slow_path);
4852 mono_mb_emit_ldarg (mb, 0);
4853 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
4854 mono_mb_emit_byte (mb, CEE_RET);
4858 mono_mb_emit_ldarg (mb, 0);
4859 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
4860 mono_mb_emit_byte (mb, CEE_RET);
4863 res = mono_mb_create_method (mb, sig, 16);
4866 mono_loader_lock ();
4867 if (write_barrier_method) {
4868 /* Already created */
4869 mono_free_method (res);
4871 /* double-checked locking */
4872 mono_memory_barrier ();
4873 write_barrier_method = res;
4875 mono_loader_unlock ();
4877 return write_barrier_method;
4881 mono_gc_get_description (void)
4883 return g_strdup ("sgen");
4887 mono_gc_set_desktop_mode (void)
4892 mono_gc_is_moving (void)
4898 mono_gc_is_disabled (void)
4904 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
4911 sgen_get_nursery_clear_policy (void)
4913 return nursery_clear_policy;
4917 sgen_get_array_fill_vtable (void)
4919 if (!array_fill_vtable) {
4920 static MonoClass klass;
4921 static MonoVTable vtable;
4924 MonoDomain *domain = mono_get_root_domain ();
4927 klass.element_class = mono_defaults.byte_class;
4929 klass.instance_size = sizeof (MonoArray);
4930 klass.sizes.element_size = 1;
4931 klass.name = "array_filler_type";
4933 vtable.klass = &klass;
4935 vtable.gc_descr = mono_gc_make_descr_for_array (TRUE, &bmap, 0, 1);
4938 array_fill_vtable = &vtable;
4940 return array_fill_vtable;
4950 sgen_gc_unlock (void)
4956 sgen_major_collector_iterate_live_block_ranges (sgen_cardtable_block_callback callback)
4958 major_collector.iterate_live_block_ranges (callback);
4962 sgen_major_collector_scan_card_table (SgenGrayQueue *queue)
4964 major_collector.scan_card_table (queue);
4968 sgen_get_major_collector (void)
4970 return &major_collector;
4973 void mono_gc_set_skip_thread (gboolean skip)
4975 SgenThreadInfo *info = mono_thread_info_current ();
4978 info->gc_disabled = skip;
4983 sgen_get_remset (void)
4989 mono_gc_get_vtable_bits (MonoClass *class)
4991 if (sgen_need_bridge_processing () && sgen_is_bridge_class (class))
4992 return SGEN_GC_BIT_BRIDGE_OBJECT;
4997 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
5004 sgen_check_whole_heap_stw (void)
5006 sgen_stop_world (0);
5007 sgen_clear_nursery_fragments ();
5008 sgen_check_whole_heap ();
5009 sgen_restart_world (0, NULL);
5013 sgen_gc_event_moves (void)
5015 if (moved_objects_idx) {
5016 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
5017 moved_objects_idx = 0;
5021 #endif /* HAVE_SGEN_GC */