3 * SGen features specific to Mono.
5 * Copyright (C) 2014 Xamarin Inc
7 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
13 #include "sgen/sgen-gc.h"
14 #include "sgen/sgen-protocol.h"
15 #include "metadata/monitor.h"
16 #include "sgen/sgen-layout-stats.h"
17 #include "sgen/sgen-client.h"
18 #include "sgen/sgen-cardtable.h"
19 #include "sgen/sgen-pinning.h"
20 #include "sgen/sgen-workers.h"
21 #include "metadata/marshal.h"
22 #include "metadata/method-builder.h"
23 #include "metadata/abi-details.h"
24 #include "metadata/mono-gc.h"
25 #include "metadata/runtime.h"
26 #include "metadata/sgen-bridge-internals.h"
27 #include "metadata/gc-internals.h"
28 #include "metadata/handle.h"
29 #include "utils/mono-memory-model.h"
30 #include "utils/mono-logger-internals.h"
31 #include "utils/mono-threads-coop.h"
32 #include "utils/mono-threads.h"
33 #include "metadata/w32handle.h"
35 #ifdef HEAVY_STATISTICS
36 static guint64 stat_wbarrier_set_arrayref = 0;
37 static guint64 stat_wbarrier_value_copy = 0;
38 static guint64 stat_wbarrier_object_copy = 0;
40 static guint64 los_marked_cards;
41 static guint64 los_array_cards;
42 static guint64 los_array_remsets;
45 /* If set, mark stacks conservatively, even if precise marking is possible */
46 static gboolean conservative_stack_mark = FALSE;
47 /* If set, check that there are no references to the domain left at domain unload */
48 gboolean sgen_mono_xdomain_checks = FALSE;
50 /* Functions supplied by the runtime to be called by the GC */
51 static MonoGCCallbacks gc_callbacks;
53 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
55 #define OPDEF(a,b,c,d,e,f,g,h,i,j) \
59 #include "mono/cil/opcode.def"
70 ptr_on_stack (void *ptr)
72 gpointer stack_start = &stack_start;
73 SgenThreadInfo *info = mono_thread_info_current ();
75 if (ptr >= stack_start && ptr < (gpointer)info->client_info.info.stack_end)
80 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
82 #define HANDLE_PTR(ptr,obj) do { \
83 gpointer o = *(gpointer*)(ptr); \
85 gpointer d = ((char*)dest) + ((char*)(ptr) - (char*)(obj)); \
86 binary_protocol_wbarrier (d, o, (gpointer) SGEN_LOAD_VTABLE (o)); \
91 scan_object_for_binary_protocol_copy_wbarrier (gpointer dest, char *start, mword desc)
93 #define SCAN_OBJECT_NOVTABLE
94 #include "sgen/sgen-scan-object.h"
99 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
101 HEAVY_STAT (++stat_wbarrier_value_copy);
102 g_assert (klass->valuetype);
104 SGEN_LOG (8, "Adding value remset at %p, count %d, descr %p for class %s (%p)", dest, count, (gpointer)klass->gc_descr, klass->name, klass);
106 if (sgen_ptr_in_nursery (dest) || ptr_on_stack (dest) || !sgen_gc_descr_has_references ((mword)klass->gc_descr)) {
107 size_t element_size = mono_class_value_size (klass, NULL);
108 size_t size = count * element_size;
109 mono_gc_memmove_atomic (dest, src, size);
113 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
114 if (binary_protocol_is_heavy_enabled ()) {
115 size_t element_size = mono_class_value_size (klass, NULL);
117 for (i = 0; i < count; ++i) {
118 scan_object_for_binary_protocol_copy_wbarrier ((char*)dest + i * element_size,
119 (char*)src + i * element_size - sizeof (MonoObject),
120 (mword) klass->gc_descr);
125 sgen_get_remset ()->wbarrier_value_copy (dest, src, count, mono_class_value_size (klass, NULL));
129 * mono_gc_wbarrier_object_copy:
131 * Write barrier to call when \p obj is the result of a clone or copy of an object.
134 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
138 HEAVY_STAT (++stat_wbarrier_object_copy);
140 SGEN_ASSERT (6, !ptr_on_stack (obj), "Why is this called for a non-reference type?");
141 if (sgen_ptr_in_nursery (obj) || !SGEN_OBJECT_HAS_REFERENCES (src)) {
142 size = mono_object_class (obj)->instance_size;
143 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
144 size - sizeof (MonoObject));
148 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
149 if (binary_protocol_is_heavy_enabled ())
150 scan_object_for_binary_protocol_copy_wbarrier (obj, (char*)src, (mword) src->vtable->gc_descr);
153 sgen_get_remset ()->wbarrier_object_copy (obj, src);
157 * mono_gc_wbarrier_set_arrayref:
160 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
162 HEAVY_STAT (++stat_wbarrier_set_arrayref);
163 if (sgen_ptr_in_nursery (slot_ptr)) {
164 *(void**)slot_ptr = value;
167 SGEN_LOG (8, "Adding remset at %p", slot_ptr);
169 binary_protocol_wbarrier (slot_ptr, value, value->vtable);
171 sgen_get_remset ()->wbarrier_set_field ((GCObject*)arr, slot_ptr, value);
175 * mono_gc_wbarrier_set_field:
178 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
180 mono_gc_wbarrier_set_arrayref ((MonoArray*)obj, field_ptr, value);
184 mono_gc_wbarrier_range_copy (gpointer _dest, gpointer _src, int size)
186 sgen_wbarrier_range_copy (_dest, _src, size);
190 mono_gc_get_range_copy_func (void)
192 return sgen_get_remset ()->wbarrier_range_copy;
196 mono_gc_get_suspend_signal (void)
198 return mono_threads_suspend_get_suspend_signal ();
202 mono_gc_get_restart_signal (void)
204 return mono_threads_suspend_get_restart_signal ();
207 static MonoMethod *write_barrier_conc_method;
208 static MonoMethod *write_barrier_noconc_method;
211 sgen_is_critical_method (MonoMethod *method)
213 return sgen_is_managed_allocator (method);
217 sgen_has_critical_method (void)
219 return sgen_has_managed_allocator ();
223 mono_gc_is_critical_method (MonoMethod *method)
225 return sgen_is_critical_method (method);
231 emit_nursery_check (MonoMethodBuilder *mb, int *nursery_check_return_labels, gboolean is_concurrent)
233 int shifted_nursery_start = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
235 memset (nursery_check_return_labels, 0, sizeof (int) * 2);
236 // if (ptr_in_nursery (ptr)) return;
238 * Masking out the bits might be faster, but we would have to use 64 bit
239 * immediates, which might be slower.
241 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
242 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_START);
243 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
244 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
245 mono_mb_emit_byte (mb, CEE_SHR_UN);
246 mono_mb_emit_stloc (mb, shifted_nursery_start);
248 mono_mb_emit_ldarg (mb, 0);
249 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
250 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
251 mono_mb_emit_byte (mb, CEE_SHR_UN);
252 mono_mb_emit_ldloc (mb, shifted_nursery_start);
253 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BEQ);
255 if (!is_concurrent) {
256 // if (!ptr_in_nursery (*ptr)) return;
257 mono_mb_emit_ldarg (mb, 0);
258 mono_mb_emit_byte (mb, CEE_LDIND_I);
259 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
260 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
261 mono_mb_emit_byte (mb, CEE_SHR_UN);
262 mono_mb_emit_ldloc (mb, shifted_nursery_start);
263 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BNE_UN);
269 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
272 MonoMethodBuilder *mb;
273 MonoMethodSignature *sig;
274 MonoMethod **write_barrier_method_addr;
276 #ifdef MANAGED_WBARRIER
277 int i, nursery_check_labels [2];
280 // FIXME: Maybe create a separate version for ctors (the branch would be
281 // correctly predicted more times)
283 write_barrier_method_addr = &write_barrier_conc_method;
285 write_barrier_method_addr = &write_barrier_noconc_method;
287 if (*write_barrier_method_addr)
288 return *write_barrier_method_addr;
290 /* Create the IL version of mono_gc_barrier_generic_store () */
291 sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
292 sig->ret = &mono_defaults.void_class->byval_arg;
293 sig->params [0] = &mono_defaults.int_class->byval_arg;
296 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_conc", MONO_WRAPPER_WRITE_BARRIER);
298 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_noconc", MONO_WRAPPER_WRITE_BARRIER);
301 #ifdef MANAGED_WBARRIER
302 emit_nursery_check (mb, nursery_check_labels, is_concurrent);
304 addr = sgen_cardtable + ((address >> CARD_BITS) & CARD_MASK)
308 LDC_PTR sgen_cardtable
314 if (SGEN_HAVE_OVERLAPPING_CARDS) {
315 LDC_PTR card_table_mask
322 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
323 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_CARD_TABLE);
324 mono_mb_emit_ldarg (mb, 0);
325 mono_mb_emit_icon (mb, CARD_BITS);
326 mono_mb_emit_byte (mb, CEE_SHR_UN);
327 mono_mb_emit_byte (mb, CEE_CONV_I);
328 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
329 #if SIZEOF_VOID_P == 8
330 mono_mb_emit_icon8 (mb, CARD_MASK);
332 mono_mb_emit_icon (mb, CARD_MASK);
334 mono_mb_emit_byte (mb, CEE_CONV_I);
335 mono_mb_emit_byte (mb, CEE_AND);
337 mono_mb_emit_byte (mb, CEE_ADD);
338 mono_mb_emit_icon (mb, 1);
339 mono_mb_emit_byte (mb, CEE_STIND_I1);
342 for (i = 0; i < 2; ++i) {
343 if (nursery_check_labels [i])
344 mono_mb_patch_branch (mb, nursery_check_labels [i]);
346 mono_mb_emit_byte (mb, CEE_RET);
348 mono_mb_emit_ldarg (mb, 0);
349 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
350 mono_mb_emit_byte (mb, CEE_RET);
353 res = mono_mb_create_method (mb, sig, 16);
354 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
355 mono_marshal_set_wrapper_info (res, info);
359 if (*write_barrier_method_addr) {
360 /* Already created */
361 mono_free_method (res);
363 /* double-checked locking */
364 mono_memory_barrier ();
365 *write_barrier_method_addr = res;
369 return *write_barrier_method_addr;
373 mono_gc_get_write_barrier (void)
375 return mono_gc_get_specific_write_barrier (major_collector.is_concurrent);
379 * Dummy filler objects
382 /* Vtable of the objects used to fill out nursery fragments before a collection */
383 static GCVTable array_fill_vtable;
386 get_array_fill_vtable (void)
388 if (!array_fill_vtable) {
389 static MonoClass klass;
390 static char _vtable[sizeof(MonoVTable)+8];
391 MonoVTable* vtable = (MonoVTable*) ALIGN_TO((mword)_vtable, 8);
394 MonoDomain *domain = mono_get_root_domain ();
397 klass.element_class = mono_defaults.byte_class;
399 klass.instance_size = MONO_SIZEOF_MONO_ARRAY;
400 klass.sizes.element_size = 1;
401 klass.name = "array_filler_type";
403 vtable->klass = &klass;
405 vtable->gc_descr = mono_gc_make_descr_for_array (TRUE, &bmap, 0, 1);
408 array_fill_vtable = vtable;
410 return array_fill_vtable;
414 sgen_client_array_fill_range (char *start, size_t size)
418 if (size < MONO_SIZEOF_MONO_ARRAY) {
419 memset (start, 0, size);
423 o = (MonoArray*)start;
424 o->obj.vtable = (MonoVTable*)get_array_fill_vtable ();
425 /* Mark this as not a real object */
426 o->obj.synchronisation = (MonoThreadsSync *)GINT_TO_POINTER (-1);
428 o->max_length = (mono_array_size_t)(size - MONO_SIZEOF_MONO_ARRAY);
434 sgen_client_zero_array_fill_header (void *p, size_t size)
436 if (size >= MONO_SIZEOF_MONO_ARRAY) {
437 memset (p, 0, MONO_SIZEOF_MONO_ARRAY);
439 static guint8 zeros [MONO_SIZEOF_MONO_ARRAY];
441 SGEN_ASSERT (0, !memcmp (p, zeros, size), "TLAB segment must be zeroed out.");
449 static MonoGCFinalizerCallbacks fin_callbacks;
452 mono_gc_get_vtable_bits (MonoClass *klass)
455 /* FIXME move this to the bridge code */
456 if (sgen_need_bridge_processing ()) {
457 switch (sgen_bridge_class_kind (klass)) {
458 case GC_BRIDGE_TRANSPARENT_BRIDGE_CLASS:
459 case GC_BRIDGE_OPAQUE_BRIDGE_CLASS:
460 res = SGEN_GC_BIT_BRIDGE_OBJECT;
462 case GC_BRIDGE_OPAQUE_CLASS:
463 res = SGEN_GC_BIT_BRIDGE_OPAQUE_OBJECT;
465 case GC_BRIDGE_TRANSPARENT_CLASS:
469 if (fin_callbacks.is_class_finalization_aware) {
470 if (fin_callbacks.is_class_finalization_aware (klass))
471 res |= SGEN_GC_BIT_FINALIZER_AWARE;
477 is_finalization_aware (MonoObject *obj)
479 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
480 return (vt->gc_bits & SGEN_GC_BIT_FINALIZER_AWARE) == SGEN_GC_BIT_FINALIZER_AWARE;
484 sgen_client_object_queued_for_finalization (GCObject *obj)
486 if (fin_callbacks.object_queued_for_finalization && is_finalization_aware (obj))
487 fin_callbacks.object_queued_for_finalization (obj);
490 if (G_UNLIKELY (MONO_GC_FINALIZE_ENQUEUE_ENABLED ())) {
491 int gen = sgen_ptr_in_nursery (obj) ? GENERATION_NURSERY : GENERATION_OLD;
492 GCVTable vt = SGEN_LOAD_VTABLE (obj);
493 MONO_GC_FINALIZE_ENQUEUE ((mword)obj, sgen_safe_object_get_size (obj),
494 sgen_client_vtable_get_namespace (vt), sgen_client_vtable_get_name (vt), gen,
495 sgen_client_object_has_critical_finalizer (obj));
501 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
503 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
504 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
506 fin_callbacks = *callbacks;
510 sgen_client_run_finalize (MonoObject *obj)
512 mono_gc_run_finalize (obj, NULL);
516 * mono_gc_invoke_finalizers:
519 mono_gc_invoke_finalizers (void)
521 return sgen_gc_invoke_finalizers ();
525 * mono_gc_pending_finalizers:
528 mono_gc_pending_finalizers (void)
530 return sgen_have_pending_finalizers ();
534 sgen_client_finalize_notify (void)
536 mono_gc_finalize_notify ();
540 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
542 sgen_object_register_for_finalization (obj, user_data);
546 object_in_domain_predicate (MonoObject *obj, void *user_data)
548 MonoDomain *domain = (MonoDomain *)user_data;
549 if (mono_object_domain (obj) == domain) {
550 SGEN_LOG (5, "Unregistering finalizer for object: %p (%s)", obj, sgen_client_vtable_get_name (SGEN_LOAD_VTABLE (obj)));
557 * mono_gc_finalizers_for_domain:
558 * \param domain the unloading appdomain
559 * \param out_array output array
560 * \param out_size size of output array
561 * Enqueue for finalization all objects that belong to the unloading appdomain \p domain.
562 * \p suspend is used for early termination of the enqueuing process.
565 mono_gc_finalize_domain (MonoDomain *domain)
567 sgen_finalize_if (object_in_domain_predicate, domain);
571 mono_gc_suspend_finalizers (void)
573 sgen_set_suspend_finalizers ();
580 typedef struct _EphemeronLinkNode EphemeronLinkNode;
582 struct _EphemeronLinkNode {
583 EphemeronLinkNode *next;
592 static EphemeronLinkNode *ephemeron_list;
594 /* LOCKING: requires that the GC lock is held */
596 null_ephemerons_for_domain (MonoDomain *domain)
598 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
601 MonoObject *object = (MonoObject*)current->array;
604 SGEN_ASSERT (0, object->vtable, "Can't have objects without vtables.");
606 if (object && object->vtable->domain == domain) {
607 EphemeronLinkNode *tmp = current;
610 prev->next = current->next;
612 ephemeron_list = current->next;
614 current = current->next;
615 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
618 current = current->next;
623 /* LOCKING: requires that the GC lock is held */
625 sgen_client_clear_unreachable_ephemerons (ScanCopyContext ctx)
627 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
628 SgenGrayQueue *queue = ctx.queue;
629 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
630 Ephemeron *cur, *array_end;
634 MonoArray *array = current->array;
636 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
637 EphemeronLinkNode *tmp = current;
639 SGEN_LOG (5, "Dead Ephemeron array at %p", array);
642 prev->next = current->next;
644 ephemeron_list = current->next;
646 current = current->next;
647 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
652 copy_func ((GCObject**)&array, queue);
653 current->array = array;
655 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", array);
657 cur = mono_array_addr (array, Ephemeron, 0);
658 array_end = cur + mono_array_length_fast (array);
659 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
661 for (; cur < array_end; ++cur) {
662 GCObject *key = cur->key;
664 if (!key || key == tombstone)
667 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
668 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
669 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
671 if (!sgen_is_object_alive_for_current_gen (key)) {
672 cur->key = tombstone;
678 current = current->next;
683 LOCKING: requires that the GC lock is held
685 Limitations: We scan all ephemerons on every collection since the current design doesn't allow for a simple nursery/mature split.
688 sgen_client_mark_ephemerons (ScanCopyContext ctx)
690 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
691 SgenGrayQueue *queue = ctx.queue;
692 gboolean nothing_marked = TRUE;
693 EphemeronLinkNode *current = ephemeron_list;
694 Ephemeron *cur, *array_end;
697 for (current = ephemeron_list; current; current = current->next) {
698 MonoArray *array = current->array;
699 SGEN_LOG (5, "Ephemeron array at %p", array);
701 /*It has to be alive*/
702 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
703 SGEN_LOG (5, "\tnot reachable");
707 copy_func ((GCObject**)&array, queue);
709 cur = mono_array_addr (array, Ephemeron, 0);
710 array_end = cur + mono_array_length_fast (array);
711 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
713 for (; cur < array_end; ++cur) {
714 GCObject *key = cur->key;
716 if (!key || key == tombstone)
719 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
720 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
721 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
723 if (sgen_is_object_alive_for_current_gen (key)) {
724 GCObject *value = cur->value;
726 copy_func (&cur->key, queue);
728 if (!sgen_is_object_alive_for_current_gen (value))
729 nothing_marked = FALSE;
730 copy_func (&cur->value, queue);
736 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
737 return nothing_marked;
741 mono_gc_ephemeron_array_add (MonoObject *obj)
743 EphemeronLinkNode *node;
747 node = (EphemeronLinkNode *)sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
752 node->array = (MonoArray*)obj;
753 node->next = ephemeron_list;
754 ephemeron_list = node;
756 SGEN_LOG (5, "Registered ephemeron array %p", obj);
767 need_remove_object_for_domain (GCObject *start, MonoDomain *domain)
769 if (mono_object_domain (start) == domain) {
770 SGEN_LOG (4, "Need to cleanup object %p", start);
771 binary_protocol_cleanup (start, (gpointer)SGEN_LOAD_VTABLE (start), sgen_safe_object_get_size ((GCObject*)start));
778 process_object_for_domain_clearing (GCObject *start, MonoDomain *domain)
780 MonoVTable *vt = SGEN_LOAD_VTABLE (start);
781 if (vt->klass == mono_defaults.internal_thread_class)
782 g_assert (mono_object_domain (start) == mono_get_root_domain ());
783 /* The object could be a proxy for an object in the domain
785 #ifndef DISABLE_REMOTING
786 if (mono_defaults.real_proxy_class->supertypes && mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
787 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
789 /* The server could already have been zeroed out, so
790 we need to check for that, too. */
791 if (server && (!SGEN_LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
792 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
793 ((MonoRealProxy*)start)->unwrapped_server = NULL;
800 clear_domain_process_object (GCObject *obj, MonoDomain *domain)
804 process_object_for_domain_clearing (obj, domain);
805 remove = need_remove_object_for_domain (obj, domain);
807 if (remove && obj->synchronisation) {
808 guint32 dislink = mono_monitor_get_object_monitor_gchandle (obj);
810 mono_gchandle_free (dislink);
817 clear_domain_process_minor_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
819 if (clear_domain_process_object (obj, domain)) {
820 CANARIFY_SIZE (size);
821 memset (obj, 0, size);
826 clear_domain_process_major_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
828 clear_domain_process_object (obj, domain);
832 clear_domain_free_major_non_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
834 if (need_remove_object_for_domain (obj, domain))
835 major_collector.free_non_pinned_object (obj, size);
839 clear_domain_free_major_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
841 if (need_remove_object_for_domain (obj, domain))
842 major_collector.free_pinned_object (obj, size);
846 * When appdomains are unloaded we can easily remove objects that have finalizers,
847 * but all the others could still be present in random places on the heap.
848 * We need a sweep to get rid of them even though it's going to be costly
850 * The reason we need to remove them is because we access the vtable and class
851 * structures to know the object size and the reference bitmap: once the domain is
852 * unloaded the point to random memory.
855 mono_gc_clear_domain (MonoDomain * domain)
857 LOSObject *bigobj, *prev;
862 binary_protocol_domain_unload_begin (domain);
866 if (sgen_concurrent_collection_in_progress ())
867 sgen_perform_collection (0, GENERATION_OLD, "clear domain", TRUE, FALSE);
868 SGEN_ASSERT (0, !sgen_concurrent_collection_in_progress (), "We just ordered a synchronous collection. Why are we collecting concurrently?");
870 major_collector.finish_sweeping ();
872 sgen_process_fin_stage_entries ();
874 sgen_clear_nursery_fragments ();
876 FOREACH_THREAD (info) {
877 mono_handle_stack_free_domain ((HandleStack*)info->client_info.info.handle_stack, domain);
880 if (sgen_mono_xdomain_checks && domain != mono_get_root_domain ()) {
881 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
882 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
883 sgen_check_for_xdomain_refs ();
886 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
887 to memory returned to the OS.*/
888 null_ephemerons_for_domain (domain);
889 sgen_null_links_for_domain (domain);
891 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
892 sgen_remove_finalizers_if (object_in_domain_predicate, domain, i);
894 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
895 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE, TRUE);
897 /* We need two passes over major and large objects because
898 freeing such objects might give their memory back to the OS
899 (in the case of large objects) or obliterate its vtable
900 (pinned objects with major-copying or pinned and non-pinned
901 objects with major-mark&sweep), but we might need to
902 dereference a pointer from an object to another object if
903 the first object is a proxy. */
904 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
905 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
906 clear_domain_process_object ((GCObject*)bigobj->data, domain);
909 for (bigobj = los_object_list; bigobj;) {
910 if (need_remove_object_for_domain ((GCObject*)bigobj->data, domain)) {
911 LOSObject *to_free = bigobj;
913 prev->next = bigobj->next;
915 los_object_list = bigobj->next;
916 bigobj = bigobj->next;
917 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
918 sgen_los_free_object (to_free);
922 bigobj = bigobj->next;
924 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
925 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
927 if (domain == mono_get_root_domain ()) {
928 sgen_pin_stats_report ();
929 sgen_object_layout_dump (stdout);
932 sgen_restart_world (0);
934 binary_protocol_domain_unload_end (domain);
935 binary_protocol_flush_buffers (FALSE);
945 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
947 MonoObject *obj = sgen_alloc_obj (vtable, size);
949 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS)) {
951 mono_profiler_allocation (obj);
958 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
960 MonoObject *obj = sgen_alloc_obj_pinned (vtable, size);
962 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS)) {
964 mono_profiler_allocation (obj);
971 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
973 MonoObject *obj = sgen_alloc_obj_mature (vtable, size);
975 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS)) {
977 mono_profiler_allocation (obj);
984 * mono_gc_alloc_fixed:
987 mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
989 /* FIXME: do a single allocation */
990 void *res = g_calloc (1, size);
993 if (!mono_gc_register_root ((char *)res, size, descr, source, msg)) {
1001 * mono_gc_free_fixed:
1004 mono_gc_free_fixed (void* addr)
1006 mono_gc_deregister_root ((char *)addr);
1014 static MonoMethod* alloc_method_cache [ATYPE_NUM];
1015 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
1016 static gboolean use_managed_allocator = TRUE;
1018 #ifdef MANAGED_ALLOCATION
1019 // Cache the SgenThreadInfo pointer in a local 'var'.
1020 #define EMIT_TLS_ACCESS_VAR(mb, var) \
1022 var = mono_mb_add_local ((mb), &mono_defaults.int_class->byval_arg); \
1023 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1024 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1025 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_THREAD_INFO); \
1026 mono_mb_emit_stloc ((mb), (var)); \
1029 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, var) \
1031 mono_mb_emit_ldloc ((mb), (var)); \
1032 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenClientThreadInfo, in_critical_region)); \
1033 mono_mb_emit_byte ((mb), CEE_ADD); \
1036 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, var) do { \
1037 mono_mb_emit_ldloc ((mb), (var)); \
1038 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_next)); \
1039 mono_mb_emit_byte ((mb), CEE_ADD); \
1042 #define EMIT_TLS_ACCESS_TEMP_END(mb, var) do { \
1043 mono_mb_emit_ldloc ((mb), (var)); \
1044 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_temp_end)); \
1045 mono_mb_emit_byte ((mb), CEE_ADD); \
1046 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1049 /* FIXME: Do this in the JIT, where specialized allocation sequences can be created
1050 * for each class. This is currently not easy to do, as it is hard to generate basic
1051 * blocks + branches, but it is easy with the linear IL codebase.
1053 * For this to work we'd need to solve the TLAB race, first. Now we
1054 * require the allocator to be in a few known methods to make sure
1055 * that they are executed atomically via the restart mechanism.
1058 create_allocator (int atype, ManagedAllocatorVariant variant)
1060 int p_var, size_var, real_size_var, thread_var G_GNUC_UNUSED;
1061 gboolean slowpath = variant == MANAGED_ALLOCATOR_SLOW_PATH;
1062 guint32 fastpath_branch, max_size_branch, no_oom_branch;
1063 MonoMethodBuilder *mb;
1065 MonoMethodSignature *csig;
1066 static gboolean registered = FALSE;
1067 int tlab_next_addr_var, new_next_var;
1068 const char *name = NULL;
1073 mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
1074 mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
1075 mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE);
1079 if (atype == ATYPE_SMALL) {
1080 name = slowpath ? "SlowAllocSmall" : "AllocSmall";
1081 } else if (atype == ATYPE_NORMAL) {
1082 name = slowpath ? "SlowAlloc" : "Alloc";
1083 } else if (atype == ATYPE_VECTOR) {
1084 name = slowpath ? "SlowAllocVector" : "AllocVector";
1085 } else if (atype == ATYPE_STRING) {
1086 name = slowpath ? "SlowAllocString" : "AllocString";
1088 g_assert_not_reached ();
1091 if (atype == ATYPE_NORMAL)
1096 csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
1097 if (atype == ATYPE_STRING) {
1098 csig->ret = &mono_defaults.string_class->byval_arg;
1099 csig->params [0] = &mono_defaults.int_class->byval_arg;
1100 csig->params [1] = &mono_defaults.int32_class->byval_arg;
1102 csig->ret = &mono_defaults.object_class->byval_arg;
1103 for (i = 0; i < num_params; i++)
1104 csig->params [i] = &mono_defaults.int_class->byval_arg;
1107 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
1114 mono_mb_emit_ldarg (mb, 0);
1115 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1118 mono_mb_emit_ldarg (mb, 0);
1119 mono_mb_emit_ldarg (mb, 1);
1120 mono_mb_emit_icall (mb, ves_icall_array_new_specific);
1123 mono_mb_emit_ldarg (mb, 1);
1124 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1127 g_assert_not_reached ();
1134 * Tls access might call foreign code or code without jinfo. This can
1135 * only happen if we are outside of the critical region.
1137 EMIT_TLS_ACCESS_VAR (mb, thread_var);
1139 size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1140 if (atype == ATYPE_SMALL) {
1141 /* size_var = size_arg */
1142 mono_mb_emit_ldarg (mb, 1);
1143 mono_mb_emit_stloc (mb, size_var);
1144 } else if (atype == ATYPE_NORMAL) {
1145 /* size = vtable->klass->instance_size; */
1146 mono_mb_emit_ldarg (mb, 0);
1147 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1148 mono_mb_emit_byte (mb, CEE_ADD);
1149 mono_mb_emit_byte (mb, CEE_LDIND_I);
1150 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, instance_size));
1151 mono_mb_emit_byte (mb, CEE_ADD);
1152 /* FIXME: assert instance_size stays a 4 byte integer */
1153 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1154 mono_mb_emit_byte (mb, CEE_CONV_I);
1155 mono_mb_emit_stloc (mb, size_var);
1156 } else if (atype == ATYPE_VECTOR) {
1157 MonoExceptionClause *clause;
1158 int pos, pos_leave, pos_error;
1159 MonoClass *oom_exc_class;
1163 * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException
1164 * n < 0 => OverflowException
1166 * We can do an unsigned comparison to catch both cases, then in the error
1167 * case compare signed to distinguish between them.
1169 mono_mb_emit_ldarg (mb, 1);
1170 mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
1171 mono_mb_emit_byte (mb, CEE_CONV_U);
1172 pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
1174 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1175 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1176 mono_mb_emit_ldarg (mb, 1);
1177 mono_mb_emit_icon (mb, 0);
1178 pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S);
1179 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1180 mono_mb_patch_short_branch (mb, pos_error);
1181 mono_mb_emit_exception (mb, "OverflowException", NULL);
1183 mono_mb_patch_short_branch (mb, pos);
1185 clause = (MonoExceptionClause *)mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
1186 clause->try_offset = mono_mb_get_label (mb);
1188 /* vtable->klass->sizes.element_size */
1189 mono_mb_emit_ldarg (mb, 0);
1190 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1191 mono_mb_emit_byte (mb, CEE_ADD);
1192 mono_mb_emit_byte (mb, CEE_LDIND_I);
1193 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, sizes));
1194 mono_mb_emit_byte (mb, CEE_ADD);
1195 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1196 mono_mb_emit_byte (mb, CEE_CONV_I);
1199 mono_mb_emit_ldarg (mb, 1);
1200 mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
1201 /* + sizeof (MonoArray) */
1202 mono_mb_emit_icon (mb, MONO_SIZEOF_MONO_ARRAY);
1203 mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
1204 mono_mb_emit_stloc (mb, size_var);
1206 pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);
1209 clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
1210 clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
1211 clause->data.catch_class = mono_class_load_from_name (mono_defaults.corlib,
1212 "System", "OverflowException");
1213 clause->handler_offset = mono_mb_get_label (mb);
1215 oom_exc_class = mono_class_load_from_name (mono_defaults.corlib,
1216 "System", "OutOfMemoryException");
1217 ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
1220 mono_mb_emit_byte (mb, CEE_POP);
1221 mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
1222 mono_mb_emit_byte (mb, CEE_THROW);
1224 clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
1225 mono_mb_set_clauses (mb, 1, clause);
1226 mono_mb_patch_branch (mb, pos_leave);
1228 } else if (atype == ATYPE_STRING) {
1232 * a string allocator method takes the args: (vtable, len)
1234 * bytes = offsetof (MonoString, chars) + ((len + 1) * 2)
1238 * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1242 * offsetof (MonoString, chars) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1243 * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - offsetof (MonoString, chars)) / 2 - 1
1245 mono_mb_emit_ldarg (mb, 1);
1246 mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - MONO_STRUCT_OFFSET (MonoString, chars)) / 2 - 1);
1247 pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
1249 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1250 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1251 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1252 mono_mb_patch_short_branch (mb, pos);
1254 mono_mb_emit_ldarg (mb, 1);
1255 mono_mb_emit_icon (mb, 1);
1256 mono_mb_emit_byte (mb, MONO_CEE_SHL);
1257 //WE manually fold the above + 2 here
1258 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, chars) + 2);
1259 mono_mb_emit_byte (mb, CEE_ADD);
1260 mono_mb_emit_stloc (mb, size_var);
1262 g_assert_not_reached ();
1265 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1266 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1267 mono_mb_emit_byte (mb, CEE_LDC_I4_1);
1268 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1269 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1270 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1273 if (nursery_canaries_enabled ()) {
1274 real_size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1275 mono_mb_emit_ldloc (mb, size_var);
1276 mono_mb_emit_stloc(mb, real_size_var);
1279 real_size_var = size_var;
1281 /* size += ALLOC_ALIGN - 1; */
1282 mono_mb_emit_ldloc (mb, size_var);
1283 mono_mb_emit_icon (mb, SGEN_ALLOC_ALIGN - 1);
1284 mono_mb_emit_byte (mb, CEE_ADD);
1285 /* size &= ~(ALLOC_ALIGN - 1); */
1286 mono_mb_emit_icon (mb, ~(SGEN_ALLOC_ALIGN - 1));
1287 mono_mb_emit_byte (mb, CEE_AND);
1288 mono_mb_emit_stloc (mb, size_var);
1290 /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
1291 if (atype != ATYPE_SMALL) {
1292 mono_mb_emit_ldloc (mb, size_var);
1293 mono_mb_emit_icon (mb, SGEN_MAX_SMALL_OBJ_SIZE);
1294 max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
1298 * We need to modify tlab_next, but the JIT only supports reading, so we read
1299 * another tls var holding its address instead.
1302 /* tlab_next_addr (local) = tlab_next_addr (TLS var) */
1303 tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1304 EMIT_TLS_ACCESS_NEXT_ADDR (mb, thread_var);
1305 mono_mb_emit_stloc (mb, tlab_next_addr_var);
1307 /* p = (void**)tlab_next; */
1308 p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1309 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1310 mono_mb_emit_byte (mb, CEE_LDIND_I);
1311 mono_mb_emit_stloc (mb, p_var);
1313 /* new_next = (char*)p + size; */
1314 new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1315 mono_mb_emit_ldloc (mb, p_var);
1316 mono_mb_emit_ldloc (mb, size_var);
1317 mono_mb_emit_byte (mb, CEE_CONV_I);
1318 mono_mb_emit_byte (mb, CEE_ADD);
1320 if (nursery_canaries_enabled ()) {
1321 mono_mb_emit_icon (mb, CANARY_SIZE);
1322 mono_mb_emit_byte (mb, CEE_ADD);
1324 mono_mb_emit_stloc (mb, new_next_var);
1326 /* if (G_LIKELY (new_next < tlab_temp_end)) */
1327 mono_mb_emit_ldloc (mb, new_next_var);
1328 EMIT_TLS_ACCESS_TEMP_END (mb, thread_var);
1329 fastpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1332 if (atype != ATYPE_SMALL)
1333 mono_mb_patch_short_branch (mb, max_size_branch);
1335 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1336 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1338 * We are no longer in a critical section. We need to do this before calling
1339 * to unmanaged land in order to avoid stw deadlocks since unmanaged code
1342 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1343 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1344 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1345 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1346 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1347 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1350 /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
1351 mono_mb_emit_ldarg (mb, 0);
1352 mono_mb_emit_ldloc (mb, real_size_var);
1353 if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
1354 mono_mb_emit_icall (mb, mono_gc_alloc_obj);
1355 } else if (atype == ATYPE_VECTOR) {
1356 mono_mb_emit_ldarg (mb, 1);
1357 mono_mb_emit_icall (mb, mono_gc_alloc_vector);
1358 } else if (atype == ATYPE_STRING) {
1359 mono_mb_emit_ldarg (mb, 1);
1360 mono_mb_emit_icall (mb, mono_gc_alloc_string);
1362 g_assert_not_reached ();
1365 /* if (ret == NULL) throw OOM; */
1366 mono_mb_emit_byte (mb, CEE_DUP);
1367 no_oom_branch = mono_mb_emit_branch (mb, CEE_BRTRUE);
1368 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1370 mono_mb_patch_branch (mb, no_oom_branch);
1371 mono_mb_emit_byte (mb, CEE_RET);
1374 mono_mb_patch_short_branch (mb, fastpath_branch);
1376 /* FIXME: Memory barrier */
1378 /* tlab_next = new_next */
1379 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1380 mono_mb_emit_ldloc (mb, new_next_var);
1381 mono_mb_emit_byte (mb, CEE_STIND_I);
1384 mono_mb_emit_ldloc (mb, p_var);
1385 mono_mb_emit_ldarg (mb, 0);
1386 mono_mb_emit_byte (mb, CEE_STIND_I);
1388 /* mark object end with nursery word */
1389 if (nursery_canaries_enabled ()) {
1390 mono_mb_emit_ldloc (mb, p_var);
1391 mono_mb_emit_ldloc (mb, real_size_var);
1392 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1393 mono_mb_emit_icon8 (mb, (mword) CANARY_STRING);
1394 mono_mb_emit_icon (mb, CANARY_SIZE);
1395 mono_mb_emit_byte (mb, MONO_CEE_PREFIX1);
1396 mono_mb_emit_byte (mb, CEE_CPBLK);
1399 if (atype == ATYPE_VECTOR) {
1400 /* arr->max_length = max_length; */
1401 mono_mb_emit_ldloc (mb, p_var);
1402 mono_mb_emit_ldflda (mb, MONO_STRUCT_OFFSET (MonoArray, max_length));
1403 mono_mb_emit_ldarg (mb, 1);
1404 #ifdef MONO_BIG_ARRAYS
1405 mono_mb_emit_byte (mb, CEE_STIND_I);
1407 mono_mb_emit_byte (mb, CEE_STIND_I4);
1409 } else if (atype == ATYPE_STRING) {
1410 /* need to set length and clear the last char */
1411 /* s->length = len; */
1412 mono_mb_emit_ldloc (mb, p_var);
1413 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, length));
1414 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1415 mono_mb_emit_ldarg (mb, 1);
1416 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1419 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1420 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1421 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1422 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1423 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1425 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1426 mono_mb_emit_byte (mb, CEE_MONO_MEMORY_BARRIER);
1429 We must make sure both vtable and max_length are globaly visible before returning to managed land.
1431 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_REL);
1434 mono_mb_emit_ldloc (mb, p_var);
1437 mono_mb_emit_byte (mb, CEE_RET);
1440 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1441 info->d.alloc.gc_name = "sgen";
1442 info->d.alloc.alloc_type = atype;
1445 mb->init_locals = FALSE;
1448 res = mono_mb_create (mb, csig, 8, info);
1457 mono_gc_get_aligned_size_for_allocator (int size)
1459 return SGEN_ALIGN_UP (size);
1463 * Generate an allocator method implementing the fast path of mono_gc_alloc_obj ().
1464 * The signature of the called method is:
1465 * object allocate (MonoVTable *vtable)
1468 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1470 #ifdef MANAGED_ALLOCATION
1471 if (collect_before_allocs)
1473 if (klass->instance_size > tlab_size)
1475 if (known_instance_size && ALIGN_TO (klass->instance_size, SGEN_ALLOC_ALIGN) >= SGEN_MAX_SMALL_OBJ_SIZE)
1477 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1481 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1483 if (klass->byval_arg.type == MONO_TYPE_STRING)
1484 return mono_gc_get_managed_allocator_by_type (ATYPE_STRING, MANAGED_ALLOCATOR_REGULAR);
1485 /* Generic classes have dynamic field and can go above MAX_SMALL_OBJ_SIZE. */
1486 if (known_instance_size)
1487 return mono_gc_get_managed_allocator_by_type (ATYPE_SMALL, MANAGED_ALLOCATOR_REGULAR);
1489 return mono_gc_get_managed_allocator_by_type (ATYPE_NORMAL, MANAGED_ALLOCATOR_REGULAR);
1496 mono_gc_get_managed_array_allocator (MonoClass *klass)
1498 #ifdef MANAGED_ALLOCATION
1499 if (klass->rank != 1)
1501 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1503 if (has_per_allocation_action)
1505 g_assert (!mono_class_has_finalizer (klass) && !mono_class_is_marshalbyref (klass));
1507 return mono_gc_get_managed_allocator_by_type (ATYPE_VECTOR, MANAGED_ALLOCATOR_REGULAR);
1514 sgen_set_use_managed_allocator (gboolean flag)
1516 use_managed_allocator = flag;
1520 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1522 #ifdef MANAGED_ALLOCATION
1526 if (variant == MANAGED_ALLOCATOR_REGULAR && !use_managed_allocator)
1530 case MANAGED_ALLOCATOR_REGULAR: cache = alloc_method_cache; break;
1531 case MANAGED_ALLOCATOR_SLOW_PATH: cache = slowpath_alloc_method_cache; break;
1532 default: g_assert_not_reached (); break;
1535 res = cache [atype];
1539 res = create_allocator (atype, variant);
1541 if (cache [atype]) {
1542 mono_free_method (res);
1543 res = cache [atype];
1545 mono_memory_barrier ();
1546 cache [atype] = res;
1557 mono_gc_get_managed_allocator_types (void)
1563 sgen_is_managed_allocator (MonoMethod *method)
1567 for (i = 0; i < ATYPE_NUM; ++i)
1568 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1574 sgen_has_managed_allocator (void)
1578 for (i = 0; i < ATYPE_NUM; ++i)
1579 if (alloc_method_cache [i] || slowpath_alloc_method_cache [i])
1584 #define ARRAY_OBJ_INDEX(ptr,array,elem_size) (((char*)(ptr) - ((char*)(array) + G_STRUCT_OFFSET (MonoArray, vector))) / (elem_size))
1587 sgen_client_cardtable_scan_object (GCObject *obj, guint8 *cards, ScanCopyContext ctx)
1589 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
1590 MonoClass *klass = vt->klass;
1592 SGEN_ASSERT (0, SGEN_VTABLE_HAS_REFERENCES (vt), "Why would we ever call this on reference-free objects?");
1595 MonoArray *arr = (MonoArray*)obj;
1596 guint8 *card_data, *card_base;
1597 guint8 *card_data_end;
1598 char *obj_start = (char *)sgen_card_table_align_pointer (obj);
1600 mword obj_size = sgen_mono_array_size (vt, arr, &bounds_size, sgen_vtable_get_descriptor (vt));
1601 /* We don't want to scan the bounds entries at the end of multidimensional arrays */
1602 char *obj_end = (char*)obj + obj_size - bounds_size;
1604 size_t extra_idx = 0;
1606 mword desc = (mword)klass->element_class->gc_descr;
1607 int elem_size = mono_array_element_size (klass);
1609 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1610 guint8 *overflow_scan_end = NULL;
1613 #ifdef SGEN_OBJECT_LAYOUT_STATISTICS
1614 if (klass->element_class->valuetype)
1615 sgen_object_layout_scanned_vtype_array ();
1617 sgen_object_layout_scanned_ref_array ();
1623 card_data = sgen_card_table_get_card_scan_address ((mword)obj);
1625 card_base = card_data;
1626 card_count = sgen_card_table_number_of_cards_in_range ((mword)obj, obj_size);
1627 card_data_end = card_data + card_count;
1630 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1631 /*Check for overflow and if so, setup to scan in two steps*/
1632 if (!cards && card_data_end >= SGEN_SHADOW_CARDTABLE_END) {
1633 overflow_scan_end = sgen_shadow_cardtable + (card_data_end - SGEN_SHADOW_CARDTABLE_END);
1634 card_data_end = SGEN_SHADOW_CARDTABLE_END;
1640 card_data = sgen_find_next_card (card_data, card_data_end);
1641 for (; card_data < card_data_end; card_data = sgen_find_next_card (card_data + 1, card_data_end)) {
1643 size_t idx = (card_data - card_base) + extra_idx;
1644 char *start = (char*)(obj_start + idx * CARD_SIZE_IN_BYTES);
1645 char *card_end = start + CARD_SIZE_IN_BYTES;
1646 char *first_elem, *elem;
1648 HEAVY_STAT (++los_marked_cards);
1651 sgen_card_table_prepare_card_for_scanning (card_data);
1653 card_end = MIN (card_end, obj_end);
1655 if (start <= (char*)arr->vector)
1658 index = ARRAY_OBJ_INDEX (start, obj, elem_size);
1660 elem = first_elem = (char*)mono_array_addr_with_size_fast ((MonoArray*)obj, elem_size, index);
1661 if (klass->element_class->valuetype) {
1662 ScanVTypeFunc scan_vtype_func = ctx.ops->scan_vtype;
1664 for (; elem < card_end; elem += elem_size)
1665 scan_vtype_func (obj, elem, desc, ctx.queue BINARY_PROTOCOL_ARG (elem_size));
1667 ScanPtrFieldFunc scan_ptr_field_func = ctx.ops->scan_ptr_field;
1669 HEAVY_STAT (++los_array_cards);
1670 for (; elem < card_end; elem += SIZEOF_VOID_P)
1671 scan_ptr_field_func (obj, (GCObject**)elem, ctx.queue);
1674 binary_protocol_card_scan (first_elem, elem - first_elem);
1677 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1678 if (overflow_scan_end) {
1679 extra_idx = card_data - card_base;
1680 card_base = card_data = sgen_shadow_cardtable;
1681 card_data_end = overflow_scan_end;
1682 overflow_scan_end = NULL;
1693 * Array and string allocation
1697 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
1702 if (!SGEN_CAN_ALIGN_UP (size))
1705 #ifndef DISABLE_CRITICAL_REGION
1706 ENTER_CRITICAL_REGION;
1707 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1709 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1710 arr->max_length = (mono_array_size_t)max_length;
1711 EXIT_CRITICAL_REGION;
1714 EXIT_CRITICAL_REGION;
1719 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1720 if (G_UNLIKELY (!arr)) {
1725 arr->max_length = (mono_array_size_t)max_length;
1730 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
1731 mono_profiler_allocation (&arr->obj);
1733 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Vector has incorrect size.");
1738 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
1741 MonoArrayBounds *bounds;
1744 if (!SGEN_CAN_ALIGN_UP (size))
1747 #ifndef DISABLE_CRITICAL_REGION
1748 ENTER_CRITICAL_REGION;
1749 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1751 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1752 arr->max_length = (mono_array_size_t)max_length;
1754 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1755 arr->bounds = bounds;
1756 EXIT_CRITICAL_REGION;
1759 EXIT_CRITICAL_REGION;
1764 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1765 if (G_UNLIKELY (!arr)) {
1770 arr->max_length = (mono_array_size_t)max_length;
1772 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1773 arr->bounds = bounds;
1778 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
1779 mono_profiler_allocation (&arr->obj);
1781 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Array has incorrect size.");
1786 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
1791 if (!SGEN_CAN_ALIGN_UP (size))
1794 #ifndef DISABLE_CRITICAL_REGION
1795 ENTER_CRITICAL_REGION;
1796 str = (MonoString*)sgen_try_alloc_obj_nolock (vtable, size);
1798 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1800 EXIT_CRITICAL_REGION;
1803 EXIT_CRITICAL_REGION;
1808 str = (MonoString*)sgen_alloc_obj_nolock (vtable, size);
1809 if (G_UNLIKELY (!str)) {
1819 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
1820 mono_profiler_allocation (&str->object);
1830 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1832 mono_unichar2 *new_end = str->chars + new_length;
1834 /* zero the discarded string. This null-delimits the string and allows
1835 * the space to be reclaimed by SGen. */
1837 if (nursery_canaries_enabled () && sgen_ptr_in_nursery (str)) {
1838 CHECK_CANARY_FOR_OBJECT ((GCObject*)str, TRUE);
1839 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2) + CANARY_SIZE);
1840 memcpy (new_end + 1 , CANARY_STRING, CANARY_SIZE);
1842 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1845 str->length = new_length;
1852 #define GC_ROOT_NUM 32
1854 int count; /* must be the first field */
1855 void *objects [GC_ROOT_NUM];
1856 int root_types [GC_ROOT_NUM];
1857 uintptr_t extra_info [GC_ROOT_NUM];
1861 notify_gc_roots (GCRootReport *report)
1865 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
1870 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
1872 if (report->count == GC_ROOT_NUM)
1873 notify_gc_roots (report);
1874 report->objects [report->count] = object;
1875 report->root_types [report->count] = rtype;
1876 report->extra_info [report->count++] = (uintptr_t)SGEN_LOAD_VTABLE (object)->klass;
1880 sgen_client_nursery_objects_pinned (void **definitely_pinned, int count)
1882 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1883 GCRootReport report;
1886 for (idx = 0; idx < count; ++idx)
1887 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1888 notify_gc_roots (&report);
1893 report_finalizer_roots_from_queue (SgenPointerQueue *queue)
1895 GCRootReport report;
1899 for (i = 0; i < queue->next_slot; ++i) {
1900 void *obj = queue->data [i];
1903 add_profile_gc_root (&report, obj, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1905 notify_gc_roots (&report);
1909 report_finalizer_roots (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
1911 report_finalizer_roots_from_queue (fin_ready_queue);
1912 report_finalizer_roots_from_queue (critical_fin_queue);
1915 static GCRootReport *root_report;
1918 single_arg_report_root (MonoObject **obj, void *gc_data)
1921 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1925 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1927 switch (desc & ROOT_DESC_TYPE_MASK) {
1928 case ROOT_DESC_BITMAP:
1929 desc >>= ROOT_DESC_TYPE_SHIFT;
1931 if ((desc & 1) && *start_root) {
1932 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1938 case ROOT_DESC_COMPLEX: {
1939 gsize *bitmap_data = (gsize *)sgen_get_complex_descriptor_bitmap (desc);
1940 gsize bwords = (*bitmap_data) - 1;
1941 void **start_run = start_root;
1943 while (bwords-- > 0) {
1944 gsize bmap = *bitmap_data++;
1945 void **objptr = start_run;
1947 if ((bmap & 1) && *objptr) {
1948 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
1953 start_run += GC_BITS_PER_WORD;
1957 case ROOT_DESC_VECTOR: {
1960 for (p = start_root; p < end_root; p++) {
1962 add_profile_gc_root (report, *p, MONO_PROFILE_GC_ROOT_OTHER, 0);
1966 case ROOT_DESC_USER: {
1967 MonoGCRootMarkFunc marker = (MonoGCRootMarkFunc)sgen_get_user_descriptor_func (desc);
1968 root_report = report;
1969 marker ((MonoObject**)start_root, single_arg_report_root, NULL);
1972 case ROOT_DESC_RUN_LEN:
1973 g_assert_not_reached ();
1975 g_assert_not_reached ();
1980 report_registered_roots_by_type (int root_type)
1982 GCRootReport report;
1986 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], void **, start_root, RootRecord *, root) {
1987 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
1988 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
1989 } SGEN_HASH_TABLE_FOREACH_END;
1990 notify_gc_roots (&report);
1994 report_registered_roots (void)
1996 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
1997 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
2001 sgen_client_collecting_minor (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2003 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2004 report_registered_roots ();
2005 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2006 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2009 static GCRootReport major_root_report;
2010 static gboolean profile_roots;
2013 sgen_client_collecting_major_1 (void)
2015 profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2016 memset (&major_root_report, 0, sizeof (GCRootReport));
2020 sgen_client_pinned_los_object (GCObject *obj)
2023 add_profile_gc_root (&major_root_report, (char*)obj, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2027 sgen_client_collecting_major_2 (void)
2030 notify_gc_roots (&major_root_report);
2032 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2033 report_registered_roots ();
2037 sgen_client_collecting_major_3 (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2039 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2040 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2043 #define MOVED_OBJECTS_NUM 64
2044 static void *moved_objects [MOVED_OBJECTS_NUM];
2045 static int moved_objects_idx = 0;
2047 static SgenPointerQueue moved_objects_queue = SGEN_POINTER_QUEUE_INIT (INTERNAL_MEM_MOVED_OBJECT);
2050 mono_sgen_register_moved_object (void *obj, void *destination)
2053 * This function can be called from SGen's worker threads. We want to try
2054 * and avoid exposing those threads to the profiler API, so queue up move
2055 * events and send them later when the main GC thread calls
2056 * mono_sgen_gc_event_moves ().
2058 * TODO: Once SGen has multiple worker threads, we need to switch to a
2059 * lock-free data structure for the queue as multiple threads will be
2060 * adding to it at the same time.
2062 if (sgen_workers_is_worker_thread (mono_native_thread_id_get ())) {
2063 sgen_pointer_queue_add (&moved_objects_queue, obj);
2064 sgen_pointer_queue_add (&moved_objects_queue, destination);
2066 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2067 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2068 moved_objects_idx = 0;
2071 moved_objects [moved_objects_idx++] = obj;
2072 moved_objects [moved_objects_idx++] = destination;
2077 mono_sgen_gc_event_moves (void)
2079 while (!sgen_pointer_queue_is_empty (&moved_objects_queue)) {
2080 void *dst = sgen_pointer_queue_pop (&moved_objects_queue);
2081 void *src = sgen_pointer_queue_pop (&moved_objects_queue);
2083 mono_sgen_register_moved_object (src, dst);
2086 if (moved_objects_idx) {
2087 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2088 moved_objects_idx = 0;
2096 #define REFS_SIZE 128
2099 MonoGCReferences callback;
2103 MonoObject *refs [REFS_SIZE];
2104 uintptr_t offsets [REFS_SIZE];
2108 #define HANDLE_PTR(ptr,obj) do { \
2110 if (hwi->count == REFS_SIZE) { \
2111 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
2115 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
2116 hwi->refs [hwi->count++] = *(ptr); \
2121 collect_references (HeapWalkInfo *hwi, GCObject *obj, size_t size)
2123 char *start = (char*)obj;
2124 mword desc = sgen_obj_get_descriptor (obj);
2126 #include "sgen/sgen-scan-object.h"
2130 walk_references (GCObject *start, size_t size, void *data)
2132 HeapWalkInfo *hwi = (HeapWalkInfo *)data;
2135 collect_references (hwi, start, size);
2136 if (hwi->count || !hwi->called)
2137 hwi->callback (start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
2141 * mono_gc_walk_heap:
2142 * \param flags flags for future use
2143 * \param callback a function pointer called for each object in the heap
2144 * \param data a user data pointer that is passed to callback
2145 * This function can be used to iterate over all the live objects in the heap;
2146 * for each object, \p callback is invoked, providing info about the object's
2147 * location in memory, its class, its size and the objects it references.
2148 * For each referenced object its offset from the object address is
2149 * reported in the offsets array.
2150 * The object references may be buffered, so the callback may be invoked
2151 * multiple times for the same object: in all but the first call, the size
2152 * argument will be zero.
2153 * Note that this function can be only called in the \c MONO_GC_EVENT_PRE_START_WORLD
2154 * profiler event handler.
2155 * \returns a non-zero value if the GC doesn't support heap walking
2158 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
2163 hwi.callback = callback;
2166 sgen_clear_nursery_fragments ();
2167 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE, TRUE);
2169 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, walk_references, &hwi);
2170 sgen_los_iterate_objects (walk_references, &hwi);
2180 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
2182 gc_callbacks = *callbacks;
2186 mono_gc_get_gc_callbacks ()
2188 return &gc_callbacks;
2192 mono_gc_thread_attach (SgenThreadInfo *info)
2194 return sgen_thread_attach (info);
2198 sgen_client_thread_attach (SgenThreadInfo* info)
2200 mono_tls_set_sgen_thread_info (info);
2202 info->client_info.skip = 0;
2204 info->client_info.stack_start = NULL;
2206 #ifdef SGEN_POSIX_STW
2207 info->client_info.stop_count = -1;
2208 info->client_info.signal = 0;
2211 memset (&info->client_info.ctx, 0, sizeof (MonoContext));
2213 if (mono_gc_get_gc_callbacks ()->thread_attach_func)
2214 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2216 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
2218 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->client_info.info.stack_end);
2220 info->client_info.info.handle_stack = mono_handle_stack_alloc ();
2224 mono_gc_thread_detach_with_lock (SgenThreadInfo *info)
2226 return sgen_thread_detach_with_lock (info);
2230 sgen_client_thread_detach_with_lock (SgenThreadInfo *p)
2232 MonoNativeThreadId tid;
2234 mono_tls_set_sgen_thread_info (NULL);
2236 tid = mono_thread_info_get_tid (p);
2238 if (p->client_info.info.runtime_thread)
2239 mono_threads_add_joinable_thread ((gpointer)tid);
2241 if (mono_gc_get_gc_callbacks ()->thread_detach_func) {
2242 mono_gc_get_gc_callbacks ()->thread_detach_func (p->client_info.runtime_data);
2243 p->client_info.runtime_data = NULL;
2246 binary_protocol_thread_unregister ((gpointer)tid);
2247 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)tid);
2249 HandleStack *handles = (HandleStack*) p->client_info.info.handle_stack;
2250 p->client_info.info.handle_stack = NULL;
2251 mono_handle_stack_free (handles);
2255 mono_gc_set_skip_thread (gboolean skip)
2257 SgenThreadInfo *info = mono_thread_info_current ();
2260 info->client_info.gc_disabled = skip;
2264 /* If we skip scanning a thread with a non-empty handle stack, we may move an
2265 * object but fail to update the reference in the handle.
2267 HandleStack *stack = info->client_info.info.handle_stack;
2268 g_assert (stack == NULL || mono_handle_stack_is_empty (stack));
2273 mono_gc_thread_in_critical_region (SgenThreadInfo *info)
2275 return info->client_info.in_critical_region;
2279 * mono_gc_is_gc_thread:
2282 mono_gc_is_gc_thread (void)
2286 result = mono_thread_info_current () != NULL;
2292 sgen_client_thread_register_worker (void)
2294 mono_thread_info_register_small_id ();
2295 mono_native_thread_set_name (mono_native_thread_id_get (), "SGen worker");
2298 /* Variables holding start/end nursery so it won't have to be passed at every call */
2299 static void *scan_area_arg_start, *scan_area_arg_end;
2302 mono_gc_conservatively_scan_area (void *start, void *end)
2304 sgen_conservatively_pin_objects_from ((void **)start, (void **)end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
2308 mono_gc_scan_object (void *obj, void *gc_data)
2310 ScanCopyContext *ctx = (ScanCopyContext *)gc_data;
2311 ctx->ops->copy_or_mark_object ((GCObject**)&obj, ctx->queue);
2316 void **start_nursery;
2318 } PinHandleStackInteriorPtrData;
2320 /* Called when we're scanning the handle stack imprecisely and we encounter a pointer into the
2321 middle of an object.
2324 pin_handle_stack_interior_ptrs (void **ptr_slot, void *user_data)
2326 PinHandleStackInteriorPtrData *ud = (PinHandleStackInteriorPtrData *)user_data;
2327 sgen_conservatively_pin_objects_from (ptr_slot, ptr_slot+1, ud->start_nursery, ud->end_nursery, PIN_TYPE_STACK);
2332 * Mark from thread stacks and registers.
2335 sgen_client_scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, ScanCopyContext ctx)
2337 scan_area_arg_start = start_nursery;
2338 scan_area_arg_end = end_nursery;
2340 FOREACH_THREAD (info) {
2341 int skip_reason = 0;
2342 void *aligned_stack_start;
2344 if (info->client_info.skip) {
2345 SGEN_LOG (3, "Skipping dead thread %p, range: %p-%p, size: %zd", info, info->client_info.stack_start, info->client_info.info.stack_end, (char*)info->client_info.info.stack_end - (char*)info->client_info.stack_start);
2347 } else if (info->client_info.gc_disabled) {
2348 SGEN_LOG (3, "GC disabled for thread %p, range: %p-%p, size: %zd", info, info->client_info.stack_start, info->client_info.info.stack_end, (char*)info->client_info.info.stack_end - (char*)info->client_info.stack_start);
2350 } else if (!mono_thread_info_is_live (info)) {
2351 SGEN_LOG (3, "Skipping non-running thread %p, range: %p-%p, size: %zd (state %x)", info, info->client_info.stack_start, info->client_info.info.stack_end, (char*)info->client_info.info.stack_end - (char*)info->client_info.stack_start, info->client_info.info.thread_state);
2353 } else if (!info->client_info.stack_start) {
2354 SGEN_LOG (3, "Skipping starting or detaching thread %p", info);
2358 binary_protocol_scan_stack ((gpointer)mono_thread_info_get_tid (info), info->client_info.stack_start, info->client_info.info.stack_end, skip_reason);
2362 /* If we skip a thread with a non-empty handle stack and then it
2363 * resumes running we may potentially move an object but fail to
2364 * update the reference in the handle.
2366 HandleStack *stack = info->client_info.info.handle_stack;
2367 g_assert (stack == NULL || mono_handle_stack_is_empty (stack));
2372 g_assert (info->client_info.stack_start);
2373 g_assert (info->client_info.info.stack_end);
2375 aligned_stack_start = (void*)(mword) ALIGN_TO ((mword)info->client_info.stack_start, SIZEOF_VOID_P);
2377 /* Windows uses a guard page before the committed stack memory pages to detect when the
2378 stack needs to be grown. If we suspend a thread just after a function prolog has
2379 decremented the stack pointer to point into the guard page but before the thread has
2380 been able to read or write to that page, starting the stack scan at aligned_stack_start
2381 will raise a STATUS_GUARD_PAGE_VIOLATION and the process will crash. This code uses
2382 VirtualQuery() to determine whether stack_start points into the guard page and then
2383 updates aligned_stack_start to point at the next non-guard page. */
2384 MEMORY_BASIC_INFORMATION mem_info;
2385 SIZE_T result = VirtualQuery(info->client_info.stack_start, &mem_info, sizeof(mem_info));
2386 g_assert (result != 0);
2387 if (mem_info.Protect & PAGE_GUARD) {
2388 aligned_stack_start = ((char*) mem_info.BaseAddress) + mem_info.RegionSize;
2392 g_assert (info->client_info.suspend_done);
2393 SGEN_LOG (3, "Scanning thread %p, range: %p-%p, size: %zd, pinned=%zd", info, info->client_info.stack_start, info->client_info.info.stack_end, (char*)info->client_info.info.stack_end - (char*)info->client_info.stack_start, sgen_get_pinned_count ());
2394 if (mono_gc_get_gc_callbacks ()->thread_mark_func && !conservative_stack_mark) {
2395 mono_gc_get_gc_callbacks ()->thread_mark_func (info->client_info.runtime_data, (guint8 *)aligned_stack_start, (guint8 *)info->client_info.info.stack_end, precise, &ctx);
2396 } else if (!precise) {
2397 if (!conservative_stack_mark) {
2398 fprintf (stderr, "Precise stack mark not supported - disabling.\n");
2399 conservative_stack_mark = TRUE;
2401 //FIXME we should eventually use the new stack_mark from coop
2402 sgen_conservatively_pin_objects_from ((void **)aligned_stack_start, (void **)info->client_info.info.stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
2406 sgen_conservatively_pin_objects_from ((void**)&info->client_info.ctx, (void**)(&info->client_info.ctx + 1),
2407 start_nursery, end_nursery, PIN_TYPE_STACK);
2410 // This is used on Coop GC for platforms where we cannot get the data for individual registers.
2411 // We force a spill of all registers into the stack and pass a chunk of data into sgen.
2412 //FIXME under coop, for now, what we need to ensure is that we scan any extra memory from info->client_info.info.stack_end to stack_mark
2413 MonoThreadUnwindState *state = &info->client_info.info.thread_saved_state [SELF_SUSPEND_STATE_INDEX];
2414 if (state && state->gc_stackdata) {
2415 sgen_conservatively_pin_objects_from ((void **)state->gc_stackdata, (void**)((char*)state->gc_stackdata + state->gc_stackdata_size),
2416 start_nursery, end_nursery, PIN_TYPE_STACK);
2420 if (info->client_info.info.handle_stack) {
2422 Make two passes over the handle stack. On the imprecise pass, pin all
2423 objects where the handle points into the interior of the object. On the
2424 precise pass, copy or mark all the objects that have handles to the
2425 beginning of the object.
2428 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, (GcScanFunc)ctx.ops->copy_or_mark_object, ctx.queue, precise);
2430 PinHandleStackInteriorPtrData ud = { .start_nursery = start_nursery,
2431 .end_nursery = end_nursery,
2433 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, pin_handle_stack_interior_ptrs, &ud, precise);
2436 } FOREACH_THREAD_END
2440 * mono_gc_set_stack_end:
2442 * Set the end of the current threads stack to STACK_END. The stack space between
2443 * STACK_END and the real end of the threads stack will not be scanned during collections.
2446 mono_gc_set_stack_end (void *stack_end)
2448 SgenThreadInfo *info;
2451 info = mono_thread_info_current ();
2453 SGEN_ASSERT (0, stack_end < info->client_info.info.stack_end, "Can only lower stack end");
2454 info->client_info.info.stack_end = stack_end;
2464 mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2466 return sgen_register_root (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED, source, msg);
2470 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2472 return sgen_register_root (start, size, descr, ROOT_TYPE_WBARRIER, source, msg);
2476 mono_gc_deregister_root (char* addr)
2478 sgen_deregister_root (addr);
2487 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
2491 mono_threads_join_lock ();
2492 res = pthread_create (new_thread, attr, start_routine, arg);
2493 mono_threads_join_unlock ();
2504 sgen_client_total_allocated_heap_changed (size_t allocated_heap)
2506 mono_runtime_resource_check_limit (MONO_RESOURCE_GC_HEAP, allocated_heap);
2510 mono_gc_user_markers_supported (void)
2516 mono_object_is_alive (MonoObject* o)
2522 mono_gc_get_generation (MonoObject *obj)
2524 if (sgen_ptr_in_nursery (obj))
2530 mono_gc_get_gc_name (void)
2536 mono_gc_get_description (void)
2538 #ifdef HAVE_CONC_GC_AS_DEFAULT
2539 return g_strdup ("sgen (concurrent by default)");
2541 return g_strdup ("sgen");
2546 mono_gc_set_desktop_mode (void)
2551 mono_gc_is_moving (void)
2557 mono_gc_is_disabled (void)
2563 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
2570 mono_gc_max_generation (void)
2576 mono_gc_precise_stack_mark_enabled (void)
2578 return !conservative_stack_mark;
2582 mono_gc_collect (int generation)
2584 sgen_gc_collect (generation);
2588 mono_gc_collection_count (int generation)
2590 return sgen_gc_collection_count (generation);
2594 mono_gc_get_used_size (void)
2596 return (int64_t)sgen_gc_get_used_size ();
2600 mono_gc_get_heap_size (void)
2602 return (int64_t)sgen_gc_get_total_heap_allocation ();
2606 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
2608 return sgen_make_user_root_descriptor (marker);
2612 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
2614 return SGEN_DESC_STRING;
2618 mono_gc_get_nursery (int *shift_bits, size_t *size)
2620 *size = sgen_nursery_size;
2621 *shift_bits = sgen_nursery_bits;
2622 return sgen_get_nursery_start ();
2626 mono_gc_get_los_limit (void)
2628 return SGEN_MAX_SMALL_OBJ_SIZE;
2632 sgen_client_default_metadata (void)
2634 return mono_domain_get ();
2638 sgen_client_metadata_for_object (GCObject *obj)
2640 return mono_object_domain (obj);
2644 * mono_gchandle_is_in_domain:
2645 * \param gchandle a GCHandle's handle.
2646 * \param domain An application domain.
2647 * \returns TRUE if the object wrapped by the \p gchandle belongs to the specific \p domain.
2650 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
2652 MonoDomain *gchandle_domain = (MonoDomain *)sgen_gchandle_get_metadata (gchandle);
2653 return domain->domain_id == gchandle_domain->domain_id;
2657 * mono_gchandle_free_domain:
2658 * \param unloading domain that is unloading
2660 * Function used internally to cleanup any GC handle for objects belonging
2661 * to the specified domain during appdomain unload.
2664 mono_gchandle_free_domain (MonoDomain *unloading)
2669 null_link_if_in_domain (gpointer hidden, GCHandleType handle_type, int max_generation, gpointer user)
2671 MonoDomain *unloading_domain = (MonoDomain *)user;
2672 MonoDomain *obj_domain;
2673 gboolean is_weak = MONO_GC_HANDLE_TYPE_IS_WEAK (handle_type);
2674 if (MONO_GC_HANDLE_IS_OBJECT_POINTER (hidden)) {
2675 MonoObject *obj = (MonoObject *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2676 obj_domain = mono_object_domain (obj);
2678 obj_domain = (MonoDomain *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2680 if (unloading_domain->domain_id == obj_domain->domain_id)
2686 sgen_null_links_for_domain (MonoDomain *domain)
2689 for (type = HANDLE_TYPE_MIN; type < HANDLE_TYPE_MAX; ++type)
2690 sgen_gchandle_iterate ((GCHandleType)type, GENERATION_OLD, null_link_if_in_domain, domain);
2694 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
2696 sgen_gchandle_set_target (gchandle, obj);
2700 sgen_client_gchandle_created (int handle_type, GCObject *obj, guint32 handle)
2702 #ifndef DISABLE_PERFCOUNTERS
2703 mono_perfcounters->gc_num_handles++;
2705 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handle_type, handle, obj);
2709 sgen_client_gchandle_destroyed (int handle_type, guint32 handle)
2711 #ifndef DISABLE_PERFCOUNTERS
2712 mono_perfcounters->gc_num_handles--;
2714 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handle_type, handle, NULL);
2718 sgen_client_ensure_weak_gchandles_accessible (void)
2721 * During the second bridge processing step the world is
2722 * running again. That step processes all weak links once
2723 * more to null those that refer to dead objects. Before that
2724 * is completed, those links must not be followed, so we
2725 * conservatively wait for bridge processing when any weak
2726 * link is dereferenced.
2728 /* FIXME: A GC can occur after this check fails, in which case we
2729 * should wait for bridge processing but would fail to do so.
2731 if (G_UNLIKELY (bridge_processing_in_progress))
2732 mono_gc_wait_for_bridge_processing ();
2736 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
2740 result = func (data);
2741 UNLOCK_INTERRUPTION;
2746 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
2752 mono_gc_get_card_table (int *shift_bits, gpointer *mask)
2754 return sgen_get_card_table_configuration (shift_bits, mask);
2758 mono_gc_card_table_nursery_check (void)
2760 return !sgen_get_major_collector ()->is_concurrent;
2763 /* Negative value to remove */
2765 mono_gc_add_memory_pressure (gint64 value)
2767 /* FIXME: Implement at some point? */
2775 sgen_client_degraded_allocation (size_t size)
2777 static int last_major_gc_warned = -1;
2778 static int num_degraded = 0;
2780 if (last_major_gc_warned < (int)gc_stats.major_gc_count) {
2782 if (num_degraded == 1 || num_degraded == 3)
2783 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Degraded allocation. Consider increasing nursery-size if the warning persists.");
2784 else if (num_degraded == 10)
2785 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Repeated degraded allocation. Consider increasing nursery-size.");
2786 last_major_gc_warned = gc_stats.major_gc_count;
2795 sgen_client_description_for_internal_mem_type (int type)
2798 case INTERNAL_MEM_EPHEMERON_LINK: return "ephemeron-link";
2799 case INTERNAL_MEM_MOVED_OBJECT: return "moved-object";
2806 sgen_client_pre_collection_checks (void)
2808 if (sgen_mono_xdomain_checks) {
2809 sgen_clear_nursery_fragments ();
2810 sgen_check_for_xdomain_refs ();
2815 sgen_client_vtable_is_inited (MonoVTable *vt)
2817 return vt->klass->inited;
2821 sgen_client_vtable_get_namespace (MonoVTable *vt)
2823 return vt->klass->name_space;
2827 sgen_client_vtable_get_name (MonoVTable *vt)
2829 return vt->klass->name;
2837 sgen_client_init (void)
2839 mono_thread_callbacks_init ();
2840 mono_thread_info_init (sizeof (SgenThreadInfo));
2842 ///* Keep this the default for now */
2843 /* Precise marking is broken on all supported targets. Disable until fixed. */
2844 conservative_stack_mark = TRUE;
2846 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
2848 mono_sgen_init_stw ();
2850 mono_tls_init_gc_keys ();
2852 mono_thread_info_attach ();
2856 sgen_client_handle_gc_param (const char *opt)
2858 if (g_str_has_prefix (opt, "stack-mark=")) {
2859 opt = strchr (opt, '=') + 1;
2860 if (!strcmp (opt, "precise")) {
2861 conservative_stack_mark = FALSE;
2862 } else if (!strcmp (opt, "conservative")) {
2863 conservative_stack_mark = TRUE;
2865 sgen_env_var_error (MONO_GC_PARAMS_NAME, conservative_stack_mark ? "Using `conservative`." : "Using `precise`.",
2866 "Invalid value `%s` for `stack-mark` option, possible values are: `precise`, `conservative`.", opt);
2868 } else if (g_str_has_prefix (opt, "bridge-implementation=")) {
2869 opt = strchr (opt, '=') + 1;
2870 sgen_set_bridge_implementation (opt);
2871 } else if (g_str_has_prefix (opt, "toggleref-test")) {
2872 /* FIXME: This should probably in MONO_GC_DEBUG */
2873 sgen_register_test_toggleref_callback ();
2874 } else if (!sgen_bridge_handle_gc_param (opt)) {
2881 sgen_client_print_gc_params_usage (void)
2883 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
2887 sgen_client_handle_gc_debug (const char *opt)
2889 if (!strcmp (opt, "xdomain-checks")) {
2890 sgen_mono_xdomain_checks = TRUE;
2891 } else if (!strcmp (opt, "do-not-finalize")) {
2892 mono_do_not_finalize = TRUE;
2893 } else if (g_str_has_prefix (opt, "do-not-finalize=")) {
2894 opt = strchr (opt, '=') + 1;
2895 mono_do_not_finalize = TRUE;
2896 mono_do_not_finalize_class_names = g_strsplit (opt, ",", 0);
2897 } else if (!strcmp (opt, "log-finalizers")) {
2898 log_finalizers = TRUE;
2899 } else if (!strcmp (opt, "no-managed-allocator")) {
2900 sgen_set_use_managed_allocator (FALSE);
2901 } else if (!sgen_bridge_handle_gc_debug (opt)) {
2908 sgen_client_print_gc_debug_usage (void)
2910 fprintf (stderr, " xdomain-checks\n");
2911 fprintf (stderr, " do-not-finalize\n");
2912 fprintf (stderr, " log-finalizers\n");
2913 fprintf (stderr, " no-managed-allocator\n");
2914 sgen_bridge_print_gc_debug_usage ();
2919 sgen_client_get_provenance (void)
2921 #ifdef SGEN_OBJECT_PROVENANCE
2922 MonoGCCallbacks *cb = mono_gc_get_gc_callbacks ();
2923 gpointer (*get_provenance_func) (void);
2926 get_provenance_func = cb->get_provenance_func;
2927 if (get_provenance_func)
2928 return get_provenance_func ();
2936 sgen_client_describe_invalid_pointer (GCObject *ptr)
2938 sgen_bridge_describe_pointer (ptr);
2941 static gboolean gc_inited;
2944 * mono_gc_base_init:
2947 mono_gc_base_init (void)
2952 mono_counters_init ();
2955 mono_w32handle_init ();
2958 #ifdef HEAVY_STATISTICS
2959 mono_counters_register ("los marked cards", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_marked_cards);
2960 mono_counters_register ("los array cards scanned ", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_cards);
2961 mono_counters_register ("los array remsets", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_remsets);
2963 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_set_arrayref);
2964 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_value_copy);
2965 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_object_copy);
2974 mono_gc_base_cleanup (void)
2976 sgen_thread_pool_shutdown ();
2978 // We should have consumed any outstanding moves.
2979 g_assert (sgen_pointer_queue_is_empty (&moved_objects_queue));
2983 mono_gc_is_null (void)