2 * sgen-mono.c: SGen features specific to Mono.
4 * Copyright (C) 2014 Xamarin Inc
6 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
12 #include "sgen/sgen-gc.h"
13 #include "sgen/sgen-protocol.h"
14 #include "metadata/monitor.h"
15 #include "sgen/sgen-layout-stats.h"
16 #include "sgen/sgen-client.h"
17 #include "sgen/sgen-cardtable.h"
18 #include "sgen/sgen-pinning.h"
19 #include "metadata/marshal.h"
20 #include "metadata/method-builder.h"
21 #include "metadata/abi-details.h"
22 #include "metadata/mono-gc.h"
23 #include "metadata/runtime.h"
24 #include "metadata/sgen-bridge-internals.h"
25 #include "metadata/gc-internals.h"
26 #include "metadata/handle.h"
27 #include "utils/mono-memory-model.h"
28 #include "utils/mono-logger-internals.h"
29 #include "utils/mono-threads-coop.h"
30 #include "sgen/sgen-thread-pool.h"
32 #ifdef HEAVY_STATISTICS
33 static guint64 stat_wbarrier_set_arrayref = 0;
34 static guint64 stat_wbarrier_value_copy = 0;
35 static guint64 stat_wbarrier_object_copy = 0;
37 static guint64 los_marked_cards;
38 static guint64 los_array_cards;
39 static guint64 los_array_remsets;
42 /* If set, mark stacks conservatively, even if precise marking is possible */
43 static gboolean conservative_stack_mark = FALSE;
44 /* If set, check that there are no references to the domain left at domain unload */
45 gboolean sgen_mono_xdomain_checks = FALSE;
47 /* Functions supplied by the runtime to be called by the GC */
48 static MonoGCCallbacks gc_callbacks;
51 __thread SgenThreadInfo *sgen_thread_info;
53 MonoNativeTlsKey thread_info_key;
56 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
58 #define OPDEF(a,b,c,d,e,f,g,h,i,j) \
62 #include "mono/cil/opcode.def"
73 ptr_on_stack (void *ptr)
75 gpointer stack_start = &stack_start;
76 SgenThreadInfo *info = mono_thread_info_current ();
78 if (ptr >= stack_start && ptr < (gpointer)info->client_info.stack_end)
83 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
85 #define HANDLE_PTR(ptr,obj) do { \
86 gpointer o = *(gpointer*)(ptr); \
88 gpointer d = ((char*)dest) + ((char*)(ptr) - (char*)(obj)); \
89 binary_protocol_wbarrier (d, o, (gpointer) SGEN_LOAD_VTABLE (o)); \
94 scan_object_for_binary_protocol_copy_wbarrier (gpointer dest, char *start, mword desc)
96 #define SCAN_OBJECT_NOVTABLE
97 #include "sgen/sgen-scan-object.h"
102 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
104 HEAVY_STAT (++stat_wbarrier_value_copy);
105 g_assert (klass->valuetype);
107 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);
109 if (sgen_ptr_in_nursery (dest) || ptr_on_stack (dest) || !sgen_gc_descr_has_references ((mword)klass->gc_descr)) {
110 size_t element_size = mono_class_value_size (klass, NULL);
111 size_t size = count * element_size;
112 mono_gc_memmove_atomic (dest, src, size);
116 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
117 if (binary_protocol_is_heavy_enabled ()) {
118 size_t element_size = mono_class_value_size (klass, NULL);
120 for (i = 0; i < count; ++i) {
121 scan_object_for_binary_protocol_copy_wbarrier ((char*)dest + i * element_size,
122 (char*)src + i * element_size - sizeof (MonoObject),
123 (mword) klass->gc_descr);
128 sgen_get_remset ()->wbarrier_value_copy (dest, src, count, mono_class_value_size (klass, NULL));
132 * mono_gc_wbarrier_object_copy:
134 * Write barrier to call when obj is the result of a clone or copy of an object.
137 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
141 HEAVY_STAT (++stat_wbarrier_object_copy);
143 SGEN_ASSERT (6, !ptr_on_stack (obj), "Why is this called for a non-reference type?");
144 if (sgen_ptr_in_nursery (obj) || !SGEN_OBJECT_HAS_REFERENCES (src)) {
145 size = mono_object_class (obj)->instance_size;
146 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
147 size - sizeof (MonoObject));
151 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
152 if (binary_protocol_is_heavy_enabled ())
153 scan_object_for_binary_protocol_copy_wbarrier (obj, (char*)src, (mword) src->vtable->gc_descr);
156 sgen_get_remset ()->wbarrier_object_copy (obj, src);
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 (MonoObject *obj, gpointer field_ptr, MonoObject* value)
177 mono_gc_wbarrier_set_arrayref ((MonoArray*)obj, field_ptr, value);
181 mono_gc_wbarrier_value_copy_bitmap (gpointer _dest, gpointer _src, int size, unsigned bitmap)
183 sgen_wbarrier_value_copy_bitmap (_dest, _src, size, bitmap);
186 static MonoMethod *write_barrier_conc_method;
187 static MonoMethod *write_barrier_noconc_method;
190 sgen_is_critical_method (MonoMethod *method)
192 return (method == write_barrier_conc_method || method == write_barrier_noconc_method || sgen_is_managed_allocator (method));
196 sgen_has_critical_method (void)
198 return write_barrier_conc_method || write_barrier_noconc_method || sgen_has_managed_allocator ();
204 emit_nursery_check (MonoMethodBuilder *mb, int *nursery_check_return_labels, gboolean is_concurrent)
206 int shifted_nursery_start = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
208 memset (nursery_check_return_labels, 0, sizeof (int) * 2);
209 // if (ptr_in_nursery (ptr)) return;
211 * Masking out the bits might be faster, but we would have to use 64 bit
212 * immediates, which might be slower.
214 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
215 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_START);
216 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
217 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
218 mono_mb_emit_byte (mb, CEE_SHR_UN);
219 mono_mb_emit_stloc (mb, shifted_nursery_start);
221 mono_mb_emit_ldarg (mb, 0);
222 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
223 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
224 mono_mb_emit_byte (mb, CEE_SHR_UN);
225 mono_mb_emit_ldloc (mb, shifted_nursery_start);
226 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BEQ);
228 if (!is_concurrent) {
229 // if (!ptr_in_nursery (*ptr)) return;
230 mono_mb_emit_ldarg (mb, 0);
231 mono_mb_emit_byte (mb, CEE_LDIND_I);
232 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
233 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
234 mono_mb_emit_byte (mb, CEE_SHR_UN);
235 mono_mb_emit_ldloc (mb, shifted_nursery_start);
236 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BNE_UN);
242 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
245 MonoMethodBuilder *mb;
246 MonoMethodSignature *sig;
247 MonoMethod **write_barrier_method_addr;
249 #ifdef MANAGED_WBARRIER
250 int i, nursery_check_labels [2];
253 // FIXME: Maybe create a separate version for ctors (the branch would be
254 // correctly predicted more times)
256 write_barrier_method_addr = &write_barrier_conc_method;
258 write_barrier_method_addr = &write_barrier_noconc_method;
260 if (*write_barrier_method_addr)
261 return *write_barrier_method_addr;
263 /* Create the IL version of mono_gc_barrier_generic_store () */
264 sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
265 sig->ret = &mono_defaults.void_class->byval_arg;
266 sig->params [0] = &mono_defaults.int_class->byval_arg;
269 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_conc", MONO_WRAPPER_WRITE_BARRIER);
271 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_noconc", MONO_WRAPPER_WRITE_BARRIER);
274 #ifdef MANAGED_WBARRIER
275 emit_nursery_check (mb, nursery_check_labels, is_concurrent);
277 addr = sgen_cardtable + ((address >> CARD_BITS) & CARD_MASK)
281 LDC_PTR sgen_cardtable
287 if (SGEN_HAVE_OVERLAPPING_CARDS) {
288 LDC_PTR card_table_mask
295 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
296 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_CARD_TABLE);
297 mono_mb_emit_ldarg (mb, 0);
298 mono_mb_emit_icon (mb, CARD_BITS);
299 mono_mb_emit_byte (mb, CEE_SHR_UN);
300 mono_mb_emit_byte (mb, CEE_CONV_I);
301 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
302 #if SIZEOF_VOID_P == 8
303 mono_mb_emit_icon8 (mb, CARD_MASK);
305 mono_mb_emit_icon (mb, CARD_MASK);
307 mono_mb_emit_byte (mb, CEE_CONV_I);
308 mono_mb_emit_byte (mb, CEE_AND);
310 mono_mb_emit_byte (mb, CEE_ADD);
311 mono_mb_emit_icon (mb, 1);
312 mono_mb_emit_byte (mb, CEE_STIND_I1);
315 for (i = 0; i < 2; ++i) {
316 if (nursery_check_labels [i])
317 mono_mb_patch_branch (mb, nursery_check_labels [i]);
319 mono_mb_emit_byte (mb, CEE_RET);
321 mono_mb_emit_ldarg (mb, 0);
322 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
323 mono_mb_emit_byte (mb, CEE_RET);
326 res = mono_mb_create_method (mb, sig, 16);
327 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
328 mono_marshal_set_wrapper_info (res, info);
332 if (*write_barrier_method_addr) {
333 /* Already created */
334 mono_free_method (res);
336 /* double-checked locking */
337 mono_memory_barrier ();
338 *write_barrier_method_addr = res;
342 return *write_barrier_method_addr;
346 mono_gc_get_write_barrier (void)
348 return mono_gc_get_specific_write_barrier (major_collector.is_concurrent);
352 * Dummy filler objects
355 /* Vtable of the objects used to fill out nursery fragments before a collection */
356 static GCVTable array_fill_vtable;
359 get_array_fill_vtable (void)
361 if (!array_fill_vtable) {
362 static MonoClass klass;
363 static char _vtable[sizeof(MonoVTable)+8];
364 MonoVTable* vtable = (MonoVTable*) ALIGN_TO((mword)_vtable, 8);
367 MonoDomain *domain = mono_get_root_domain ();
370 klass.element_class = mono_defaults.byte_class;
372 klass.instance_size = MONO_SIZEOF_MONO_ARRAY;
373 klass.sizes.element_size = 1;
374 klass.name = "array_filler_type";
376 vtable->klass = &klass;
378 vtable->gc_descr = mono_gc_make_descr_for_array (TRUE, &bmap, 0, 1);
381 array_fill_vtable = vtable;
383 return array_fill_vtable;
387 sgen_client_array_fill_range (char *start, size_t size)
391 if (size < MONO_SIZEOF_MONO_ARRAY) {
392 memset (start, 0, size);
396 o = (MonoArray*)start;
397 o->obj.vtable = (MonoVTable*)get_array_fill_vtable ();
398 /* Mark this as not a real object */
399 o->obj.synchronisation = (MonoThreadsSync *)GINT_TO_POINTER (-1);
401 o->max_length = (mono_array_size_t)(size - MONO_SIZEOF_MONO_ARRAY);
407 sgen_client_zero_array_fill_header (void *p, size_t size)
409 if (size >= MONO_SIZEOF_MONO_ARRAY) {
410 memset (p, 0, MONO_SIZEOF_MONO_ARRAY);
412 static guint8 zeros [MONO_SIZEOF_MONO_ARRAY];
414 SGEN_ASSERT (0, !memcmp (p, zeros, size), "TLAB segment must be zeroed out.");
422 static MonoGCFinalizerCallbacks fin_callbacks;
425 mono_gc_get_vtable_bits (MonoClass *klass)
428 /* FIXME move this to the bridge code */
429 if (sgen_need_bridge_processing ()) {
430 switch (sgen_bridge_class_kind (klass)) {
431 case GC_BRIDGE_TRANSPARENT_BRIDGE_CLASS:
432 case GC_BRIDGE_OPAQUE_BRIDGE_CLASS:
433 res = SGEN_GC_BIT_BRIDGE_OBJECT;
435 case GC_BRIDGE_OPAQUE_CLASS:
436 res = SGEN_GC_BIT_BRIDGE_OPAQUE_OBJECT;
438 case GC_BRIDGE_TRANSPARENT_CLASS:
442 if (fin_callbacks.is_class_finalization_aware) {
443 if (fin_callbacks.is_class_finalization_aware (klass))
444 res |= SGEN_GC_BIT_FINALIZER_AWARE;
450 is_finalization_aware (MonoObject *obj)
452 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
453 return (vt->gc_bits & SGEN_GC_BIT_FINALIZER_AWARE) == SGEN_GC_BIT_FINALIZER_AWARE;
457 sgen_client_object_queued_for_finalization (GCObject *obj)
459 if (fin_callbacks.object_queued_for_finalization && is_finalization_aware (obj))
460 fin_callbacks.object_queued_for_finalization (obj);
463 if (G_UNLIKELY (MONO_GC_FINALIZE_ENQUEUE_ENABLED ())) {
464 int gen = sgen_ptr_in_nursery (obj) ? GENERATION_NURSERY : GENERATION_OLD;
465 GCVTable vt = SGEN_LOAD_VTABLE (obj);
466 MONO_GC_FINALIZE_ENQUEUE ((mword)obj, sgen_safe_object_get_size (obj),
467 sgen_client_vtable_get_namespace (vt), sgen_client_vtable_get_name (vt), gen,
468 sgen_client_object_has_critical_finalizer (obj));
474 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
476 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
477 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
479 fin_callbacks = *callbacks;
483 sgen_client_run_finalize (MonoObject *obj)
485 mono_gc_run_finalize (obj, NULL);
489 mono_gc_invoke_finalizers (void)
491 return sgen_gc_invoke_finalizers ();
495 mono_gc_pending_finalizers (void)
497 return sgen_have_pending_finalizers ();
501 sgen_client_finalize_notify (void)
503 mono_gc_finalize_notify ();
507 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
509 sgen_object_register_for_finalization (obj, user_data);
513 object_in_domain_predicate (MonoObject *obj, void *user_data)
515 MonoDomain *domain = (MonoDomain *)user_data;
516 if (mono_object_domain (obj) == domain) {
517 SGEN_LOG (5, "Unregistering finalizer for object: %p (%s)", obj, sgen_client_vtable_get_name (SGEN_LOAD_VTABLE (obj)));
524 * mono_gc_finalizers_for_domain:
525 * @domain: the unloading appdomain
526 * @out_array: output array
527 * @out_size: size of output array
529 * Enqueue for finalization all objects that belong to the unloading appdomain @domain
530 * @suspend is used for early termination of the enqueuing process.
533 mono_gc_finalize_domain (MonoDomain *domain, volatile gboolean *suspend)
535 sgen_finalize_if (object_in_domain_predicate, domain, suspend);
542 typedef struct _EphemeronLinkNode EphemeronLinkNode;
544 struct _EphemeronLinkNode {
545 EphemeronLinkNode *next;
554 static EphemeronLinkNode *ephemeron_list;
556 /* LOCKING: requires that the GC lock is held */
558 null_ephemerons_for_domain (MonoDomain *domain)
560 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
563 MonoObject *object = (MonoObject*)current->array;
566 SGEN_ASSERT (0, object->vtable, "Can't have objects without vtables.");
568 if (object && object->vtable->domain == domain) {
569 EphemeronLinkNode *tmp = current;
572 prev->next = current->next;
574 ephemeron_list = current->next;
576 current = current->next;
577 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
580 current = current->next;
585 /* LOCKING: requires that the GC lock is held */
587 sgen_client_clear_unreachable_ephemerons (ScanCopyContext ctx)
589 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
590 SgenGrayQueue *queue = ctx.queue;
591 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
592 Ephemeron *cur, *array_end;
596 MonoArray *array = current->array;
598 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
599 EphemeronLinkNode *tmp = current;
601 SGEN_LOG (5, "Dead Ephemeron array at %p", array);
604 prev->next = current->next;
606 ephemeron_list = current->next;
608 current = current->next;
609 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
614 copy_func ((GCObject**)&array, queue);
615 current->array = array;
617 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", array);
619 cur = mono_array_addr (array, Ephemeron, 0);
620 array_end = cur + mono_array_length_fast (array);
621 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
623 for (; cur < array_end; ++cur) {
624 GCObject *key = cur->key;
626 if (!key || key == tombstone)
629 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
630 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
631 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
633 if (!sgen_is_object_alive_for_current_gen (key)) {
634 cur->key = tombstone;
640 current = current->next;
645 LOCKING: requires that the GC lock is held
647 Limitations: We scan all ephemerons on every collection since the current design doesn't allow for a simple nursery/mature split.
650 sgen_client_mark_ephemerons (ScanCopyContext ctx)
652 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
653 SgenGrayQueue *queue = ctx.queue;
654 gboolean nothing_marked = TRUE;
655 EphemeronLinkNode *current = ephemeron_list;
656 Ephemeron *cur, *array_end;
659 for (current = ephemeron_list; current; current = current->next) {
660 MonoArray *array = current->array;
661 SGEN_LOG (5, "Ephemeron array at %p", array);
663 /*It has to be alive*/
664 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
665 SGEN_LOG (5, "\tnot reachable");
669 copy_func ((GCObject**)&array, queue);
671 cur = mono_array_addr (array, Ephemeron, 0);
672 array_end = cur + mono_array_length_fast (array);
673 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
675 for (; cur < array_end; ++cur) {
676 GCObject *key = cur->key;
678 if (!key || key == tombstone)
681 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
682 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
683 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
685 if (sgen_is_object_alive_for_current_gen (key)) {
686 GCObject *value = cur->value;
688 copy_func (&cur->key, queue);
690 if (!sgen_is_object_alive_for_current_gen (value))
691 nothing_marked = FALSE;
692 copy_func (&cur->value, queue);
698 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
699 return nothing_marked;
703 mono_gc_ephemeron_array_add (MonoObject *obj)
705 EphemeronLinkNode *node;
709 node = (EphemeronLinkNode *)sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
714 node->array = (MonoArray*)obj;
715 node->next = ephemeron_list;
716 ephemeron_list = node;
718 SGEN_LOG (5, "Registered ephemeron array %p", obj);
729 mono_gc_set_current_thread_appdomain (MonoDomain *domain)
731 SgenThreadInfo *info = mono_thread_info_current ();
733 /* Could be called from sgen_thread_unregister () with a NULL info */
736 info->client_info.stopped_domain = domain;
741 need_remove_object_for_domain (GCObject *start, MonoDomain *domain)
743 if (mono_object_domain (start) == domain) {
744 SGEN_LOG (4, "Need to cleanup object %p", start);
745 binary_protocol_cleanup (start, (gpointer)SGEN_LOAD_VTABLE (start), sgen_safe_object_get_size ((GCObject*)start));
752 process_object_for_domain_clearing (GCObject *start, MonoDomain *domain)
754 MonoVTable *vt = SGEN_LOAD_VTABLE (start);
755 if (vt->klass == mono_defaults.internal_thread_class)
756 g_assert (mono_object_domain (start) == mono_get_root_domain ());
757 /* The object could be a proxy for an object in the domain
759 #ifndef DISABLE_REMOTING
760 if (mono_defaults.real_proxy_class->supertypes && mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
761 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
763 /* The server could already have been zeroed out, so
764 we need to check for that, too. */
765 if (server && (!SGEN_LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
766 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
767 ((MonoRealProxy*)start)->unwrapped_server = NULL;
774 clear_domain_process_object (GCObject *obj, MonoDomain *domain)
778 process_object_for_domain_clearing (obj, domain);
779 remove = need_remove_object_for_domain (obj, domain);
781 if (remove && obj->synchronisation) {
782 guint32 dislink = mono_monitor_get_object_monitor_gchandle (obj);
784 mono_gchandle_free (dislink);
791 clear_domain_process_minor_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
793 if (clear_domain_process_object (obj, domain)) {
794 CANARIFY_SIZE (size);
795 memset (obj, 0, size);
800 clear_domain_process_major_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
802 clear_domain_process_object (obj, domain);
806 clear_domain_free_major_non_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
808 if (need_remove_object_for_domain (obj, domain))
809 major_collector.free_non_pinned_object (obj, size);
813 clear_domain_free_major_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
815 if (need_remove_object_for_domain (obj, domain))
816 major_collector.free_pinned_object (obj, size);
820 * When appdomains are unloaded we can easily remove objects that have finalizers,
821 * but all the others could still be present in random places on the heap.
822 * We need a sweep to get rid of them even though it's going to be costly
824 * The reason we need to remove them is because we access the vtable and class
825 * structures to know the object size and the reference bitmap: once the domain is
826 * unloaded the point to random memory.
829 mono_gc_clear_domain (MonoDomain * domain)
831 LOSObject *bigobj, *prev;
836 binary_protocol_domain_unload_begin (domain);
840 if (sgen_concurrent_collection_in_progress ())
841 sgen_perform_collection (0, GENERATION_OLD, "clear domain", TRUE, FALSE);
842 SGEN_ASSERT (0, !sgen_concurrent_collection_in_progress (), "We just ordered a synchronous collection. Why are we collecting concurrently?");
844 major_collector.finish_sweeping ();
846 sgen_process_fin_stage_entries ();
848 sgen_clear_nursery_fragments ();
850 if (sgen_mono_xdomain_checks && domain != mono_get_root_domain ()) {
851 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
852 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
853 sgen_check_for_xdomain_refs ();
856 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
857 to memory returned to the OS.*/
858 null_ephemerons_for_domain (domain);
859 sgen_null_links_for_domain (domain);
861 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
862 sgen_remove_finalizers_if (object_in_domain_predicate, domain, i);
864 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
865 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE, TRUE);
867 /* We need two passes over major and large objects because
868 freeing such objects might give their memory back to the OS
869 (in the case of large objects) or obliterate its vtable
870 (pinned objects with major-copying or pinned and non-pinned
871 objects with major-mark&sweep), but we might need to
872 dereference a pointer from an object to another object if
873 the first object is a proxy. */
874 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
875 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
876 clear_domain_process_object ((GCObject*)bigobj->data, domain);
879 for (bigobj = los_object_list; bigobj;) {
880 if (need_remove_object_for_domain ((GCObject*)bigobj->data, domain)) {
881 LOSObject *to_free = bigobj;
883 prev->next = bigobj->next;
885 los_object_list = bigobj->next;
886 bigobj = bigobj->next;
887 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
888 sgen_los_free_object (to_free);
892 bigobj = bigobj->next;
894 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
895 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
897 if (domain == mono_get_root_domain ()) {
898 sgen_pin_stats_report ();
899 sgen_object_layout_dump (stdout);
902 sgen_restart_world (0);
904 binary_protocol_domain_unload_end (domain);
905 binary_protocol_flush_buffers (FALSE);
914 static gboolean alloc_events = FALSE;
917 mono_gc_enable_alloc_events (void)
923 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
925 MonoObject *obj = sgen_alloc_obj (vtable, size);
927 if (G_UNLIKELY (alloc_events)) {
929 mono_profiler_allocation (obj);
936 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
938 MonoObject *obj = sgen_alloc_obj_pinned (vtable, size);
940 if (G_UNLIKELY (alloc_events)) {
942 mono_profiler_allocation (obj);
949 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
951 MonoObject *obj = sgen_alloc_obj_mature (vtable, size);
953 if (G_UNLIKELY (alloc_events)) {
955 mono_profiler_allocation (obj);
962 mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
964 /* FIXME: do a single allocation */
965 void *res = calloc (1, size);
968 if (!mono_gc_register_root ((char *)res, size, descr, source, msg)) {
976 mono_gc_free_fixed (void* addr)
978 mono_gc_deregister_root ((char *)addr);
986 static MonoMethod* alloc_method_cache [ATYPE_NUM];
987 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
988 static gboolean use_managed_allocator = TRUE;
990 #ifdef MANAGED_ALLOCATION
992 #ifdef HAVE_KW_THREAD
994 #define EMIT_TLS_ACCESS_VAR(_mb, _var) /* nothing to do */
996 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, _var) \
998 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
999 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1000 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_IN_CRITICAL_REGION_ADDR); \
1003 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, _var) do { \
1004 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1005 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1006 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_TLAB_NEXT_ADDR); \
1009 #define EMIT_TLS_ACCESS_TEMP_END(mb, _var) do { \
1010 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1011 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1012 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_TLAB_TEMP_END); \
1017 #if defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
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_addr)); \
1039 mono_mb_emit_byte ((mb), CEE_ADD); \
1040 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1043 #define EMIT_TLS_ACCESS_TEMP_END(mb, var) do { \
1044 mono_mb_emit_ldloc ((mb), (var)); \
1045 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_temp_end)); \
1046 mono_mb_emit_byte ((mb), CEE_ADD); \
1047 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1051 #define EMIT_TLS_ACCESS_VAR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1052 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1053 #define EMIT_TLS_ACCESS_TEMP_END(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1054 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1059 /* FIXME: Do this in the JIT, where specialized allocation sequences can be created
1060 * for each class. This is currently not easy to do, as it is hard to generate basic
1061 * blocks + branches, but it is easy with the linear IL codebase.
1063 * For this to work we'd need to solve the TLAB race, first. Now we
1064 * require the allocator to be in a few known methods to make sure
1065 * that they are executed atomically via the restart mechanism.
1068 create_allocator (int atype, ManagedAllocatorVariant variant)
1070 int p_var, size_var, thread_var G_GNUC_UNUSED;
1071 gboolean slowpath = variant == MANAGED_ALLOCATOR_SLOW_PATH;
1072 guint32 slowpath_branch, max_size_branch;
1073 MonoMethodBuilder *mb;
1075 MonoMethodSignature *csig;
1076 static gboolean registered = FALSE;
1077 int tlab_next_addr_var, new_next_var;
1078 const char *name = NULL;
1083 mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
1084 mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
1085 mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE);
1089 if (atype == ATYPE_SMALL) {
1090 name = slowpath ? "SlowAllocSmall" : "AllocSmall";
1091 } else if (atype == ATYPE_NORMAL) {
1092 name = slowpath ? "SlowAlloc" : "Alloc";
1093 } else if (atype == ATYPE_VECTOR) {
1094 name = slowpath ? "SlowAllocVector" : "AllocVector";
1095 } else if (atype == ATYPE_STRING) {
1096 name = slowpath ? "SlowAllocString" : "AllocString";
1098 g_assert_not_reached ();
1101 if (atype == ATYPE_NORMAL)
1106 csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
1107 if (atype == ATYPE_STRING) {
1108 csig->ret = &mono_defaults.string_class->byval_arg;
1109 csig->params [0] = &mono_defaults.int_class->byval_arg;
1110 csig->params [1] = &mono_defaults.int32_class->byval_arg;
1112 csig->ret = &mono_defaults.object_class->byval_arg;
1113 for (i = 0; i < num_params; i++)
1114 csig->params [i] = &mono_defaults.int_class->byval_arg;
1117 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
1124 mono_mb_emit_ldarg (mb, 0);
1125 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1128 mono_mb_emit_ldarg (mb, 0);
1129 mono_mb_emit_ldarg (mb, 1);
1130 mono_mb_emit_icall (mb, ves_icall_array_new_specific);
1133 mono_mb_emit_ldarg (mb, 1);
1134 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1137 g_assert_not_reached ();
1143 EMIT_TLS_ACCESS_VAR (mb, thread_var);
1145 size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1146 if (atype == ATYPE_SMALL) {
1147 /* size_var = size_arg */
1148 mono_mb_emit_ldarg (mb, 1);
1149 mono_mb_emit_stloc (mb, size_var);
1150 } else if (atype == ATYPE_NORMAL) {
1151 /* size = vtable->klass->instance_size; */
1152 mono_mb_emit_ldarg (mb, 0);
1153 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1154 mono_mb_emit_byte (mb, CEE_ADD);
1155 mono_mb_emit_byte (mb, CEE_LDIND_I);
1156 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, instance_size));
1157 mono_mb_emit_byte (mb, CEE_ADD);
1158 /* FIXME: assert instance_size stays a 4 byte integer */
1159 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1160 mono_mb_emit_byte (mb, CEE_CONV_I);
1161 mono_mb_emit_stloc (mb, size_var);
1162 } else if (atype == ATYPE_VECTOR) {
1163 MonoExceptionClause *clause;
1164 int pos, pos_leave, pos_error;
1165 MonoClass *oom_exc_class;
1169 * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException
1170 * n < 0 => OverflowException
1172 * We can do an unsigned comparison to catch both cases, then in the error
1173 * case compare signed to distinguish between them.
1175 mono_mb_emit_ldarg (mb, 1);
1176 mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
1177 mono_mb_emit_byte (mb, CEE_CONV_U);
1178 pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
1180 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1181 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1182 mono_mb_emit_ldarg (mb, 1);
1183 mono_mb_emit_icon (mb, 0);
1184 pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S);
1185 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1186 mono_mb_patch_short_branch (mb, pos_error);
1187 mono_mb_emit_exception (mb, "OverflowException", NULL);
1189 mono_mb_patch_short_branch (mb, pos);
1191 clause = (MonoExceptionClause *)mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
1192 clause->try_offset = mono_mb_get_label (mb);
1194 /* vtable->klass->sizes.element_size */
1195 mono_mb_emit_ldarg (mb, 0);
1196 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1197 mono_mb_emit_byte (mb, CEE_ADD);
1198 mono_mb_emit_byte (mb, CEE_LDIND_I);
1199 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, sizes));
1200 mono_mb_emit_byte (mb, CEE_ADD);
1201 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1202 mono_mb_emit_byte (mb, CEE_CONV_I);
1205 mono_mb_emit_ldarg (mb, 1);
1206 mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
1207 /* + sizeof (MonoArray) */
1208 mono_mb_emit_icon (mb, MONO_SIZEOF_MONO_ARRAY);
1209 mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
1210 mono_mb_emit_stloc (mb, size_var);
1212 pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);
1215 clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
1216 clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
1217 clause->data.catch_class = mono_class_load_from_name (mono_defaults.corlib,
1218 "System", "OverflowException");
1219 clause->handler_offset = mono_mb_get_label (mb);
1221 oom_exc_class = mono_class_load_from_name (mono_defaults.corlib,
1222 "System", "OutOfMemoryException");
1223 ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
1226 mono_mb_emit_byte (mb, CEE_POP);
1227 mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
1228 mono_mb_emit_byte (mb, CEE_THROW);
1230 clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
1231 mono_mb_set_clauses (mb, 1, clause);
1232 mono_mb_patch_branch (mb, pos_leave);
1234 } else if (atype == ATYPE_STRING) {
1238 * a string allocator method takes the args: (vtable, len)
1240 * bytes = offsetof (MonoString, chars) + ((len + 1) * 2)
1244 * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1248 * offsetof (MonoString, chars) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1249 * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - offsetof (MonoString, chars)) / 2 - 1
1251 mono_mb_emit_ldarg (mb, 1);
1252 mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - MONO_STRUCT_OFFSET (MonoString, chars)) / 2 - 1);
1253 pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
1255 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1256 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1257 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1258 mono_mb_patch_short_branch (mb, pos);
1260 mono_mb_emit_ldarg (mb, 1);
1261 mono_mb_emit_icon (mb, 1);
1262 mono_mb_emit_byte (mb, MONO_CEE_SHL);
1263 //WE manually fold the above + 2 here
1264 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, chars) + 2);
1265 mono_mb_emit_byte (mb, CEE_ADD);
1266 mono_mb_emit_stloc (mb, size_var);
1268 g_assert_not_reached ();
1271 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1272 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1273 mono_mb_emit_byte (mb, CEE_LDC_I4_1);
1274 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1275 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1276 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1279 /* size += ALLOC_ALIGN - 1; */
1280 mono_mb_emit_ldloc (mb, size_var);
1281 mono_mb_emit_icon (mb, SGEN_ALLOC_ALIGN - 1);
1282 mono_mb_emit_byte (mb, CEE_ADD);
1283 /* size &= ~(ALLOC_ALIGN - 1); */
1284 mono_mb_emit_icon (mb, ~(SGEN_ALLOC_ALIGN - 1));
1285 mono_mb_emit_byte (mb, CEE_AND);
1286 mono_mb_emit_stloc (mb, size_var);
1288 /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
1289 if (atype != ATYPE_SMALL) {
1290 mono_mb_emit_ldloc (mb, size_var);
1291 mono_mb_emit_icon (mb, SGEN_MAX_SMALL_OBJ_SIZE);
1292 max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
1296 * We need to modify tlab_next, but the JIT only supports reading, so we read
1297 * another tls var holding its address instead.
1300 /* tlab_next_addr (local) = tlab_next_addr (TLS var) */
1301 tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1302 EMIT_TLS_ACCESS_NEXT_ADDR (mb, thread_var);
1303 mono_mb_emit_stloc (mb, tlab_next_addr_var);
1305 /* p = (void**)tlab_next; */
1306 p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1307 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1308 mono_mb_emit_byte (mb, CEE_LDIND_I);
1309 mono_mb_emit_stloc (mb, p_var);
1311 /* new_next = (char*)p + size; */
1312 new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1313 mono_mb_emit_ldloc (mb, p_var);
1314 mono_mb_emit_ldloc (mb, size_var);
1315 mono_mb_emit_byte (mb, CEE_CONV_I);
1316 mono_mb_emit_byte (mb, CEE_ADD);
1317 mono_mb_emit_stloc (mb, new_next_var);
1319 /* if (G_LIKELY (new_next < tlab_temp_end)) */
1320 mono_mb_emit_ldloc (mb, new_next_var);
1321 EMIT_TLS_ACCESS_TEMP_END (mb, thread_var);
1322 slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1325 if (atype != ATYPE_SMALL)
1326 mono_mb_patch_short_branch (mb, max_size_branch);
1328 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1329 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1331 * We are no longer in a critical section. We need to do this before calling
1332 * to unmanaged land in order to avoid stw deadlocks since unmanaged code
1335 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1336 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1337 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1338 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1339 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1340 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1343 /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
1344 mono_mb_emit_ldarg (mb, 0);
1345 mono_mb_emit_ldloc (mb, size_var);
1346 if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
1347 mono_mb_emit_icall (mb, mono_gc_alloc_obj);
1348 } else if (atype == ATYPE_VECTOR) {
1349 mono_mb_emit_ldarg (mb, 1);
1350 mono_mb_emit_icall (mb, mono_gc_alloc_vector);
1351 } else if (atype == ATYPE_STRING) {
1352 mono_mb_emit_ldarg (mb, 1);
1353 mono_mb_emit_icall (mb, mono_gc_alloc_string);
1355 g_assert_not_reached ();
1357 mono_mb_emit_byte (mb, CEE_RET);
1360 mono_mb_patch_short_branch (mb, slowpath_branch);
1362 /* FIXME: Memory barrier */
1364 /* tlab_next = new_next */
1365 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1366 mono_mb_emit_ldloc (mb, new_next_var);
1367 mono_mb_emit_byte (mb, CEE_STIND_I);
1370 mono_mb_emit_ldloc (mb, p_var);
1371 mono_mb_emit_ldarg (mb, 0);
1372 mono_mb_emit_byte (mb, CEE_STIND_I);
1374 if (atype == ATYPE_VECTOR) {
1375 /* arr->max_length = max_length; */
1376 mono_mb_emit_ldloc (mb, p_var);
1377 mono_mb_emit_ldflda (mb, MONO_STRUCT_OFFSET (MonoArray, max_length));
1378 mono_mb_emit_ldarg (mb, 1);
1379 #ifdef MONO_BIG_ARRAYS
1380 mono_mb_emit_byte (mb, CEE_STIND_I);
1382 mono_mb_emit_byte (mb, CEE_STIND_I4);
1384 } else if (atype == ATYPE_STRING) {
1385 /* need to set length and clear the last char */
1386 /* s->length = len; */
1387 mono_mb_emit_ldloc (mb, p_var);
1388 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, length));
1389 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1390 mono_mb_emit_ldarg (mb, 1);
1391 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1394 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1395 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1396 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1397 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1398 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1400 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1401 mono_mb_emit_byte (mb, CEE_MONO_MEMORY_BARRIER);
1404 We must make sure both vtable and max_length are globaly visible before returning to managed land.
1406 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_REL);
1409 mono_mb_emit_ldloc (mb, p_var);
1412 mono_mb_emit_byte (mb, CEE_RET);
1415 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1416 info->d.alloc.gc_name = "sgen";
1417 info->d.alloc.alloc_type = atype;
1420 mb->init_locals = FALSE;
1423 res = mono_mb_create (mb, csig, 8, info);
1432 mono_gc_get_aligned_size_for_allocator (int size)
1434 return SGEN_ALIGN_UP (size);
1438 * Generate an allocator method implementing the fast path of mono_gc_alloc_obj ().
1439 * The signature of the called method is:
1440 * object allocate (MonoVTable *vtable)
1443 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1445 #ifdef MANAGED_ALLOCATION
1446 if (collect_before_allocs)
1448 if (!mono_runtime_has_tls_get ())
1450 if (klass->instance_size > tlab_size)
1452 if (known_instance_size && ALIGN_TO (klass->instance_size, SGEN_ALLOC_ALIGN) >= SGEN_MAX_SMALL_OBJ_SIZE)
1454 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1458 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1460 if (klass->byval_arg.type == MONO_TYPE_STRING)
1461 return mono_gc_get_managed_allocator_by_type (ATYPE_STRING, MANAGED_ALLOCATOR_REGULAR);
1462 /* Generic classes have dynamic field and can go above MAX_SMALL_OBJ_SIZE. */
1463 if (known_instance_size)
1464 return mono_gc_get_managed_allocator_by_type (ATYPE_SMALL, MANAGED_ALLOCATOR_REGULAR);
1466 return mono_gc_get_managed_allocator_by_type (ATYPE_NORMAL, MANAGED_ALLOCATOR_REGULAR);
1473 mono_gc_get_managed_array_allocator (MonoClass *klass)
1475 #ifdef MANAGED_ALLOCATION
1476 if (klass->rank != 1)
1478 if (!mono_runtime_has_tls_get ())
1480 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1482 if (has_per_allocation_action)
1484 g_assert (!mono_class_has_finalizer (klass) && !mono_class_is_marshalbyref (klass));
1486 return mono_gc_get_managed_allocator_by_type (ATYPE_VECTOR, MANAGED_ALLOCATOR_REGULAR);
1493 sgen_set_use_managed_allocator (gboolean flag)
1495 use_managed_allocator = flag;
1499 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1501 #ifdef MANAGED_ALLOCATION
1505 if (!use_managed_allocator)
1508 if (!mono_runtime_has_tls_get ())
1512 case MANAGED_ALLOCATOR_REGULAR: cache = alloc_method_cache; break;
1513 case MANAGED_ALLOCATOR_SLOW_PATH: cache = slowpath_alloc_method_cache; break;
1514 default: g_assert_not_reached (); break;
1517 res = cache [atype];
1521 res = create_allocator (atype, variant);
1523 if (cache [atype]) {
1524 mono_free_method (res);
1525 res = cache [atype];
1527 mono_memory_barrier ();
1528 cache [atype] = res;
1539 mono_gc_get_managed_allocator_types (void)
1545 sgen_is_managed_allocator (MonoMethod *method)
1549 for (i = 0; i < ATYPE_NUM; ++i)
1550 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1556 sgen_has_managed_allocator (void)
1560 for (i = 0; i < ATYPE_NUM; ++i)
1561 if (alloc_method_cache [i] || slowpath_alloc_method_cache [i])
1567 * Cardtable scanning
1570 #define MWORD_MASK (sizeof (mword) - 1)
1573 find_card_offset (mword card)
1575 /*XXX Use assembly as this generates some pretty bad code */
1576 #if defined(__i386__) && defined(__GNUC__)
1577 return (__builtin_ffs (card) - 1) / 8;
1578 #elif defined(__x86_64__) && defined(__GNUC__)
1579 return (__builtin_ffsll (card) - 1) / 8;
1580 #elif defined(__s390x__)
1581 return (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1584 guint8 *ptr = (guint8 *) &card;
1585 for (i = 0; i < sizeof (mword); ++i) {
1594 find_next_card (guint8 *card_data, guint8 *end)
1596 mword *cards, *cards_end;
1599 while ((((mword)card_data) & MWORD_MASK) && card_data < end) {
1605 if (card_data == end)
1608 cards = (mword*)card_data;
1609 cards_end = (mword*)((mword)end & ~MWORD_MASK);
1610 while (cards < cards_end) {
1613 return (guint8*)cards + find_card_offset (card);
1617 card_data = (guint8*)cards_end;
1618 while (card_data < end) {
1627 #define ARRAY_OBJ_INDEX(ptr,array,elem_size) (((char*)(ptr) - ((char*)(array) + G_STRUCT_OFFSET (MonoArray, vector))) / (elem_size))
1630 sgen_client_cardtable_scan_object (GCObject *obj, mword block_obj_size, guint8 *cards, ScanCopyContext ctx)
1632 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
1633 MonoClass *klass = vt->klass;
1635 SGEN_ASSERT (0, SGEN_VTABLE_HAS_REFERENCES (vt), "Why would we ever call this on reference-free objects?");
1638 MonoArray *arr = (MonoArray*)obj;
1639 guint8 *card_data, *card_base;
1640 guint8 *card_data_end;
1641 char *obj_start = (char *)sgen_card_table_align_pointer (obj);
1643 mword obj_size = sgen_mono_array_size (vt, arr, &bounds_size, sgen_vtable_get_descriptor (vt));
1644 /* We don't want to scan the bounds entries at the end of multidimensional arrays */
1645 char *obj_end = (char*)obj + obj_size - bounds_size;
1647 size_t extra_idx = 0;
1649 mword desc = (mword)klass->element_class->gc_descr;
1650 int elem_size = mono_array_element_size (klass);
1652 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1653 guint8 *overflow_scan_end = NULL;
1656 #ifdef SGEN_OBJECT_LAYOUT_STATISTICS
1657 if (klass->element_class->valuetype)
1658 sgen_object_layout_scanned_vtype_array ();
1660 sgen_object_layout_scanned_ref_array ();
1666 card_data = sgen_card_table_get_card_scan_address ((mword)obj);
1668 card_base = card_data;
1669 card_count = sgen_card_table_number_of_cards_in_range ((mword)obj, obj_size);
1670 card_data_end = card_data + card_count;
1673 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1674 /*Check for overflow and if so, setup to scan in two steps*/
1675 if (!cards && card_data_end >= SGEN_SHADOW_CARDTABLE_END) {
1676 overflow_scan_end = sgen_shadow_cardtable + (card_data_end - SGEN_SHADOW_CARDTABLE_END);
1677 card_data_end = SGEN_SHADOW_CARDTABLE_END;
1683 card_data = find_next_card (card_data, card_data_end);
1684 for (; card_data < card_data_end; card_data = find_next_card (card_data + 1, card_data_end)) {
1686 size_t idx = (card_data - card_base) + extra_idx;
1687 char *start = (char*)(obj_start + idx * CARD_SIZE_IN_BYTES);
1688 char *card_end = start + CARD_SIZE_IN_BYTES;
1689 char *first_elem, *elem;
1691 HEAVY_STAT (++los_marked_cards);
1694 sgen_card_table_prepare_card_for_scanning (card_data);
1696 card_end = MIN (card_end, obj_end);
1698 if (start <= (char*)arr->vector)
1701 index = ARRAY_OBJ_INDEX (start, obj, elem_size);
1703 elem = first_elem = (char*)mono_array_addr_with_size_fast ((MonoArray*)obj, elem_size, index);
1704 if (klass->element_class->valuetype) {
1705 ScanVTypeFunc scan_vtype_func = ctx.ops->scan_vtype;
1707 for (; elem < card_end; elem += elem_size)
1708 scan_vtype_func (obj, elem, desc, ctx.queue BINARY_PROTOCOL_ARG (elem_size));
1710 ScanPtrFieldFunc scan_ptr_field_func = ctx.ops->scan_ptr_field;
1712 HEAVY_STAT (++los_array_cards);
1713 for (; elem < card_end; elem += SIZEOF_VOID_P)
1714 scan_ptr_field_func (obj, (GCObject**)elem, ctx.queue);
1717 binary_protocol_card_scan (first_elem, elem - first_elem);
1720 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1721 if (overflow_scan_end) {
1722 extra_idx = card_data - card_base;
1723 card_base = card_data = sgen_shadow_cardtable;
1724 card_data_end = overflow_scan_end;
1725 overflow_scan_end = NULL;
1736 * Array and string allocation
1740 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
1745 if (!SGEN_CAN_ALIGN_UP (size))
1748 #ifndef DISABLE_CRITICAL_REGION
1749 ENTER_CRITICAL_REGION;
1750 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1752 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1753 arr->max_length = (mono_array_size_t)max_length;
1754 EXIT_CRITICAL_REGION;
1757 EXIT_CRITICAL_REGION;
1762 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1763 if (G_UNLIKELY (!arr)) {
1768 arr->max_length = (mono_array_size_t)max_length;
1773 if (G_UNLIKELY (alloc_events))
1774 mono_profiler_allocation (&arr->obj);
1776 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Vector has incorrect size.");
1781 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
1784 MonoArrayBounds *bounds;
1787 if (!SGEN_CAN_ALIGN_UP (size))
1790 #ifndef DISABLE_CRITICAL_REGION
1791 ENTER_CRITICAL_REGION;
1792 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1794 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1795 arr->max_length = (mono_array_size_t)max_length;
1797 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1798 arr->bounds = bounds;
1799 EXIT_CRITICAL_REGION;
1802 EXIT_CRITICAL_REGION;
1807 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1808 if (G_UNLIKELY (!arr)) {
1813 arr->max_length = (mono_array_size_t)max_length;
1815 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1816 arr->bounds = bounds;
1821 if (G_UNLIKELY (alloc_events))
1822 mono_profiler_allocation (&arr->obj);
1824 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Array has incorrect size.");
1829 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
1834 if (!SGEN_CAN_ALIGN_UP (size))
1837 #ifndef DISABLE_CRITICAL_REGION
1838 ENTER_CRITICAL_REGION;
1839 str = (MonoString*)sgen_try_alloc_obj_nolock (vtable, size);
1841 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1843 EXIT_CRITICAL_REGION;
1846 EXIT_CRITICAL_REGION;
1851 str = (MonoString*)sgen_alloc_obj_nolock (vtable, size);
1852 if (G_UNLIKELY (!str)) {
1862 if (G_UNLIKELY (alloc_events))
1863 mono_profiler_allocation (&str->object);
1873 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1875 mono_unichar2 *new_end = str->chars + new_length;
1877 /* zero the discarded string. This null-delimits the string and allows
1878 * the space to be reclaimed by SGen. */
1880 if (nursery_canaries_enabled () && sgen_ptr_in_nursery (str)) {
1881 CHECK_CANARY_FOR_OBJECT ((GCObject*)str, TRUE);
1882 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2) + CANARY_SIZE);
1883 memcpy (new_end + 1 , CANARY_STRING, CANARY_SIZE);
1885 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1888 str->length = new_length;
1895 #define GC_ROOT_NUM 32
1897 int count; /* must be the first field */
1898 void *objects [GC_ROOT_NUM];
1899 int root_types [GC_ROOT_NUM];
1900 uintptr_t extra_info [GC_ROOT_NUM];
1904 notify_gc_roots (GCRootReport *report)
1908 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
1913 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
1915 if (report->count == GC_ROOT_NUM)
1916 notify_gc_roots (report);
1917 report->objects [report->count] = object;
1918 report->root_types [report->count] = rtype;
1919 report->extra_info [report->count++] = (uintptr_t)SGEN_LOAD_VTABLE (object)->klass;
1923 sgen_client_nursery_objects_pinned (void **definitely_pinned, int count)
1925 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1926 GCRootReport report;
1929 for (idx = 0; idx < count; ++idx)
1930 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1931 notify_gc_roots (&report);
1936 report_finalizer_roots_from_queue (SgenPointerQueue *queue)
1938 GCRootReport report;
1942 for (i = 0; i < queue->next_slot; ++i) {
1943 void *obj = queue->data [i];
1946 add_profile_gc_root (&report, obj, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1948 notify_gc_roots (&report);
1952 report_finalizer_roots (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
1954 report_finalizer_roots_from_queue (fin_ready_queue);
1955 report_finalizer_roots_from_queue (critical_fin_queue);
1958 static GCRootReport *root_report;
1961 single_arg_report_root (MonoObject **obj, void *gc_data)
1964 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1968 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1970 switch (desc & ROOT_DESC_TYPE_MASK) {
1971 case ROOT_DESC_BITMAP:
1972 desc >>= ROOT_DESC_TYPE_SHIFT;
1974 if ((desc & 1) && *start_root) {
1975 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1981 case ROOT_DESC_COMPLEX: {
1982 gsize *bitmap_data = (gsize *)sgen_get_complex_descriptor_bitmap (desc);
1983 gsize bwords = (*bitmap_data) - 1;
1984 void **start_run = start_root;
1986 while (bwords-- > 0) {
1987 gsize bmap = *bitmap_data++;
1988 void **objptr = start_run;
1990 if ((bmap & 1) && *objptr) {
1991 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
1996 start_run += GC_BITS_PER_WORD;
2000 case ROOT_DESC_USER: {
2001 MonoGCRootMarkFunc marker = (MonoGCRootMarkFunc)sgen_get_user_descriptor_func (desc);
2002 root_report = report;
2003 marker ((MonoObject**)start_root, single_arg_report_root, NULL);
2006 case ROOT_DESC_RUN_LEN:
2007 g_assert_not_reached ();
2009 g_assert_not_reached ();
2014 report_registered_roots_by_type (int root_type)
2016 GCRootReport report;
2020 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], void **, start_root, RootRecord *, root) {
2021 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
2022 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
2023 } SGEN_HASH_TABLE_FOREACH_END;
2024 notify_gc_roots (&report);
2028 report_registered_roots (void)
2030 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
2031 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
2035 sgen_client_collecting_minor (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2037 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2038 report_registered_roots ();
2039 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2040 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2043 static GCRootReport major_root_report;
2044 static gboolean profile_roots;
2047 sgen_client_collecting_major_1 (void)
2049 profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2050 memset (&major_root_report, 0, sizeof (GCRootReport));
2054 sgen_client_pinned_los_object (GCObject *obj)
2057 add_profile_gc_root (&major_root_report, (char*)obj, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2061 sgen_client_collecting_major_2 (void)
2064 notify_gc_roots (&major_root_report);
2066 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2067 report_registered_roots ();
2071 sgen_client_collecting_major_3 (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2073 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2074 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2077 #define MOVED_OBJECTS_NUM 64
2078 static void *moved_objects [MOVED_OBJECTS_NUM];
2079 static int moved_objects_idx = 0;
2082 mono_sgen_register_moved_object (void *obj, void *destination)
2084 g_assert (mono_profiler_events & MONO_PROFILE_GC_MOVES);
2086 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2087 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2088 moved_objects_idx = 0;
2090 moved_objects [moved_objects_idx++] = obj;
2091 moved_objects [moved_objects_idx++] = destination;
2095 mono_sgen_gc_event_moves (void)
2097 if (moved_objects_idx) {
2098 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2099 moved_objects_idx = 0;
2107 #define REFS_SIZE 128
2110 MonoGCReferences callback;
2114 MonoObject *refs [REFS_SIZE];
2115 uintptr_t offsets [REFS_SIZE];
2119 #define HANDLE_PTR(ptr,obj) do { \
2121 if (hwi->count == REFS_SIZE) { \
2122 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
2126 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
2127 hwi->refs [hwi->count++] = *(ptr); \
2132 collect_references (HeapWalkInfo *hwi, GCObject *obj, size_t size)
2134 char *start = (char*)obj;
2135 mword desc = sgen_obj_get_descriptor (obj);
2137 #include "sgen/sgen-scan-object.h"
2141 walk_references (GCObject *start, size_t size, void *data)
2143 HeapWalkInfo *hwi = (HeapWalkInfo *)data;
2146 collect_references (hwi, start, size);
2147 if (hwi->count || !hwi->called)
2148 hwi->callback (start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
2152 * mono_gc_walk_heap:
2153 * @flags: flags for future use
2154 * @callback: a function pointer called for each object in the heap
2155 * @data: a user data pointer that is passed to callback
2157 * This function can be used to iterate over all the live objects in the heap:
2158 * for each object, @callback is invoked, providing info about the object's
2159 * location in memory, its class, its size and the objects it references.
2160 * For each referenced object it's offset from the object address is
2161 * reported in the offsets array.
2162 * The object references may be buffered, so the callback may be invoked
2163 * multiple times for the same object: in all but the first call, the size
2164 * argument will be zero.
2165 * Note that this function can be only called in the #MONO_GC_EVENT_PRE_START_WORLD
2166 * profiler event handler.
2168 * Returns: a non-zero value if the GC doesn't support heap walking
2171 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
2176 hwi.callback = callback;
2179 sgen_clear_nursery_fragments ();
2180 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE, TRUE);
2182 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, walk_references, &hwi);
2183 sgen_los_iterate_objects (walk_references, &hwi);
2193 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
2195 gc_callbacks = *callbacks;
2199 mono_gc_get_gc_callbacks ()
2201 return &gc_callbacks;
2205 sgen_client_thread_register (SgenThreadInfo* info, void *stack_bottom_fallback)
2208 guint8 *staddr = NULL;
2210 #ifndef HAVE_KW_THREAD
2211 g_assert (!mono_native_tls_get_value (thread_info_key));
2212 mono_native_tls_set_value (thread_info_key, info);
2214 sgen_thread_info = info;
2217 info->client_info.skip = 0;
2218 info->client_info.stopped_ip = NULL;
2219 info->client_info.stopped_domain = NULL;
2221 info->client_info.stack_start = NULL;
2223 #ifdef SGEN_POSIX_STW
2224 info->client_info.stop_count = -1;
2225 info->client_info.signal = 0;
2228 /* On win32, stack_start_limit should be 0, since the stack can grow dynamically */
2229 mono_thread_info_get_stack_bounds (&staddr, &stsize);
2232 info->client_info.stack_start_limit = staddr;
2234 info->client_info.stack_end = staddr + stsize;
2236 gsize stack_bottom = (gsize)stack_bottom_fallback;
2237 stack_bottom += 4095;
2238 stack_bottom &= ~4095;
2239 info->client_info.stack_end = (char*)stack_bottom;
2242 memset (&info->client_info.ctx, 0, sizeof (MonoContext));
2244 if (mono_gc_get_gc_callbacks ()->thread_attach_func)
2245 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2247 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
2249 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->client_info.stack_end);
2251 info->client_info.info.handle_stack = mono_handle_stack_alloc ();
2255 sgen_client_thread_unregister (SgenThreadInfo *p)
2257 MonoNativeThreadId tid;
2259 #ifndef HAVE_KW_THREAD
2260 mono_native_tls_set_value (thread_info_key, NULL);
2262 sgen_thread_info = NULL;
2265 tid = mono_thread_info_get_tid (p);
2267 if (p->client_info.info.runtime_thread)
2268 mono_threads_add_joinable_thread ((gpointer)tid);
2270 if (mono_gc_get_gc_callbacks ()->thread_detach_func) {
2271 mono_gc_get_gc_callbacks ()->thread_detach_func (p->client_info.runtime_data);
2272 p->client_info.runtime_data = NULL;
2275 binary_protocol_thread_unregister ((gpointer)tid);
2276 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)tid);
2278 HandleStack *handles = (HandleStack*) p->client_info.info.handle_stack;
2279 p->client_info.info.handle_stack = NULL;
2280 mono_handle_stack_free (handles);
2284 mono_gc_set_skip_thread (gboolean skip)
2286 SgenThreadInfo *info = mono_thread_info_current ();
2289 info->client_info.gc_disabled = skip;
2294 is_critical_method (MonoMethod *method)
2296 return mono_runtime_is_critical_method (method) || sgen_is_critical_method (method);
2300 thread_in_critical_region (SgenThreadInfo *info)
2302 return info->client_info.in_critical_region;
2306 sgen_thread_attach (SgenThreadInfo *info)
2308 if (mono_gc_get_gc_callbacks ()->thread_attach_func && !info->client_info.runtime_data)
2309 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2313 sgen_thread_detach (SgenThreadInfo *p)
2315 /* If a delegate is passed to native code and invoked on a thread we dont
2316 * know about, marshal will register it with mono_threads_attach_coop, but
2317 * we have no way of knowing when that thread goes away. SGen has a TSD
2318 * so we assume that if the domain is still registered, we can detach
2321 if (mono_domain_get ())
2322 mono_thread_detach_internal (mono_thread_internal_current ());
2326 mono_gc_register_thread (void *baseptr)
2328 return mono_thread_info_attach (baseptr) != NULL;
2332 mono_gc_is_gc_thread (void)
2336 result = mono_thread_info_current () != NULL;
2342 sgen_client_thread_register_worker (void)
2344 mono_thread_info_register_small_id ();
2345 mono_native_thread_set_name (mono_native_thread_id_get (), "SGen worker");
2348 /* Variables holding start/end nursery so it won't have to be passed at every call */
2349 static void *scan_area_arg_start, *scan_area_arg_end;
2352 mono_gc_conservatively_scan_area (void *start, void *end)
2354 sgen_conservatively_pin_objects_from ((void **)start, (void **)end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
2358 mono_gc_scan_object (void *obj, void *gc_data)
2360 ScanCopyContext *ctx = (ScanCopyContext *)gc_data;
2361 ctx->ops->copy_or_mark_object ((GCObject**)&obj, ctx->queue);
2366 * Mark from thread stacks and registers.
2369 sgen_client_scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, ScanCopyContext ctx)
2371 scan_area_arg_start = start_nursery;
2372 scan_area_arg_end = end_nursery;
2374 FOREACH_THREAD (info) {
2375 int skip_reason = 0;
2376 void *aligned_stack_start;
2378 if (info->client_info.skip) {
2379 SGEN_LOG (3, "Skipping dead thread %p, range: %p-%p, size: %zd", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start);
2381 } else if (info->client_info.gc_disabled) {
2382 SGEN_LOG (3, "GC disabled for thread %p, range: %p-%p, size: %zd", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start);
2384 } else if (!mono_thread_info_is_live (info)) {
2385 SGEN_LOG (3, "Skipping non-running thread %p, range: %p-%p, size: %zd (state %x)", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start, info->client_info.info.thread_state);
2387 } else if (!info->client_info.stack_start) {
2388 SGEN_LOG (3, "Skipping starting or detaching thread %p", info);
2392 binary_protocol_scan_stack ((gpointer)mono_thread_info_get_tid (info), info->client_info.stack_start, info->client_info.stack_end, skip_reason);
2397 g_assert (info->client_info.stack_start);
2398 g_assert (info->client_info.stack_end);
2400 aligned_stack_start = (void*)(mword) ALIGN_TO ((mword)info->client_info.stack_start, SIZEOF_VOID_P);
2402 g_assert (info->client_info.suspend_done);
2403 SGEN_LOG (3, "Scanning thread %p, range: %p-%p, size: %zd, pinned=%zd", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start, sgen_get_pinned_count ());
2404 if (mono_gc_get_gc_callbacks ()->thread_mark_func && !conservative_stack_mark) {
2405 mono_gc_get_gc_callbacks ()->thread_mark_func (info->client_info.runtime_data, (guint8 *)aligned_stack_start, (guint8 *)info->client_info.stack_end, precise, &ctx);
2406 } else if (!precise) {
2407 if (!conservative_stack_mark) {
2408 fprintf (stderr, "Precise stack mark not supported - disabling.\n");
2409 conservative_stack_mark = TRUE;
2411 //FIXME we should eventually use the new stack_mark from coop
2412 sgen_conservatively_pin_objects_from ((void **)aligned_stack_start, (void **)info->client_info.stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
2416 sgen_conservatively_pin_objects_from ((void**)&info->client_info.ctx, (void**)(&info->client_info.ctx + 1),
2417 start_nursery, end_nursery, PIN_TYPE_STACK);
2420 // This is used on Coop GC for platforms where we cannot get the data for individual registers.
2421 // We force a spill of all registers into the stack and pass a chunk of data into sgen.
2422 //FIXME under coop, for now, what we need to ensure is that we scan any extra memory from info->client_info.stack_end to stack_mark
2423 MonoThreadUnwindState *state = &info->client_info.info.thread_saved_state [SELF_SUSPEND_STATE_INDEX];
2424 if (state && state->gc_stackdata) {
2425 sgen_conservatively_pin_objects_from ((void **)state->gc_stackdata, (void**)((char*)state->gc_stackdata + state->gc_stackdata_size),
2426 start_nursery, end_nursery, PIN_TYPE_STACK);
2430 if (precise && info->client_info.info.handle_stack) {
2431 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, (GcScanFunc)ctx.ops->copy_or_mark_object, ctx.queue);
2433 } FOREACH_THREAD_END
2437 * mono_gc_set_stack_end:
2439 * Set the end of the current threads stack to STACK_END. The stack space between
2440 * STACK_END and the real end of the threads stack will not be scanned during collections.
2443 mono_gc_set_stack_end (void *stack_end)
2445 SgenThreadInfo *info;
2448 info = mono_thread_info_current ();
2450 SGEN_ASSERT (0, stack_end < info->client_info.stack_end, "Can only lower stack end");
2451 info->client_info.stack_end = stack_end;
2461 mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2463 return sgen_register_root (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED, source, msg);
2467 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2469 return sgen_register_root (start, size, descr, ROOT_TYPE_WBARRIER, source, msg);
2473 mono_gc_deregister_root (char* addr)
2475 sgen_deregister_root (addr);
2484 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
2486 return pthread_create (new_thread, attr, start_routine, arg);
2495 sgen_client_total_allocated_heap_changed (size_t allocated_heap)
2497 mono_runtime_resource_check_limit (MONO_RESOURCE_GC_HEAP, allocated_heap);
2501 mono_gc_user_markers_supported (void)
2507 mono_object_is_alive (MonoObject* o)
2513 mono_gc_get_generation (MonoObject *obj)
2515 if (sgen_ptr_in_nursery (obj))
2521 mono_gc_enable_events (void)
2526 mono_gc_get_gc_name (void)
2532 mono_gc_get_description (void)
2534 #ifdef HAVE_CONC_GC_AS_DEFAULT
2535 return g_strdup ("sgen (concurrent by default)");
2537 return g_strdup ("sgen");
2542 mono_gc_set_desktop_mode (void)
2547 mono_gc_is_moving (void)
2553 mono_gc_is_disabled (void)
2559 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
2566 mono_gc_max_generation (void)
2572 mono_gc_precise_stack_mark_enabled (void)
2574 return !conservative_stack_mark;
2578 mono_gc_collect (int generation)
2580 sgen_gc_collect (generation);
2584 mono_gc_collection_count (int generation)
2586 return sgen_gc_collection_count (generation);
2590 mono_gc_get_used_size (void)
2592 return (int64_t)sgen_gc_get_used_size ();
2596 mono_gc_get_heap_size (void)
2598 return (int64_t)sgen_gc_get_total_heap_allocation ();
2602 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
2604 return sgen_make_user_root_descriptor (marker);
2608 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
2610 return SGEN_DESC_STRING;
2614 mono_gc_get_nursery (int *shift_bits, size_t *size)
2616 *size = sgen_nursery_size;
2617 *shift_bits = DEFAULT_NURSERY_BITS;
2618 return sgen_get_nursery_start ();
2622 mono_gc_get_los_limit (void)
2624 return SGEN_MAX_SMALL_OBJ_SIZE;
2628 sgen_client_default_metadata (void)
2630 return mono_domain_get ();
2634 sgen_client_metadata_for_object (GCObject *obj)
2636 return mono_object_domain (obj);
2640 * mono_gchandle_is_in_domain:
2641 * @gchandle: a GCHandle's handle.
2642 * @domain: An application domain.
2644 * Returns: TRUE if the object wrapped by the @gchandle belongs to the specific @domain.
2647 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
2649 MonoDomain *gchandle_domain = (MonoDomain *)sgen_gchandle_get_metadata (gchandle);
2650 return domain->domain_id == gchandle_domain->domain_id;
2654 * mono_gchandle_free_domain:
2655 * @unloading: domain that is unloading
2657 * Function used internally to cleanup any GC handle for objects belonging
2658 * to the specified domain during appdomain unload.
2661 mono_gchandle_free_domain (MonoDomain *unloading)
2666 null_link_if_in_domain (gpointer hidden, GCHandleType handle_type, int max_generation, gpointer user)
2668 MonoDomain *unloading_domain = (MonoDomain *)user;
2669 MonoDomain *obj_domain;
2670 gboolean is_weak = MONO_GC_HANDLE_TYPE_IS_WEAK (handle_type);
2671 if (MONO_GC_HANDLE_IS_OBJECT_POINTER (hidden)) {
2672 MonoObject *obj = (MonoObject *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2673 obj_domain = mono_object_domain (obj);
2675 obj_domain = (MonoDomain *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2677 if (unloading_domain->domain_id == obj_domain->domain_id)
2683 sgen_null_links_for_domain (MonoDomain *domain)
2686 for (type = HANDLE_TYPE_MIN; type < HANDLE_TYPE_MAX; ++type)
2687 sgen_gchandle_iterate ((GCHandleType)type, GENERATION_OLD, null_link_if_in_domain, domain);
2691 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
2693 sgen_gchandle_set_target (gchandle, obj);
2697 sgen_client_gchandle_created (int handle_type, GCObject *obj, guint32 handle)
2699 #ifndef DISABLE_PERFCOUNTERS
2700 mono_perfcounters->gc_num_handles++;
2702 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handle_type, handle, obj);
2706 sgen_client_gchandle_destroyed (int handle_type, guint32 handle)
2708 #ifndef DISABLE_PERFCOUNTERS
2709 mono_perfcounters->gc_num_handles--;
2711 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handle_type, handle, NULL);
2715 sgen_client_ensure_weak_gchandles_accessible (void)
2718 * During the second bridge processing step the world is
2719 * running again. That step processes all weak links once
2720 * more to null those that refer to dead objects. Before that
2721 * is completed, those links must not be followed, so we
2722 * conservatively wait for bridge processing when any weak
2723 * link is dereferenced.
2725 /* FIXME: A GC can occur after this check fails, in which case we
2726 * should wait for bridge processing but would fail to do so.
2728 if (G_UNLIKELY (bridge_processing_in_progress))
2729 mono_gc_wait_for_bridge_processing ();
2733 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
2737 result = func (data);
2738 UNLOCK_INTERRUPTION;
2743 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
2749 mono_gc_get_card_table (int *shift_bits, gpointer *mask)
2751 return sgen_get_card_table_configuration (shift_bits, mask);
2755 mono_gc_card_table_nursery_check (void)
2757 return !sgen_get_major_collector ()->is_concurrent;
2760 /* Negative value to remove */
2762 mono_gc_add_memory_pressure (gint64 value)
2764 /* FIXME: Implement at some point? */
2772 sgen_client_degraded_allocation (size_t size)
2774 static int last_major_gc_warned = -1;
2775 static int num_degraded = 0;
2777 if (last_major_gc_warned < (int)gc_stats.major_gc_count) {
2779 if (num_degraded == 1 || num_degraded == 3)
2780 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Degraded allocation. Consider increasing nursery-size if the warning persists.");
2781 else if (num_degraded == 10)
2782 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Repeated degraded allocation. Consider increasing nursery-size.");
2783 last_major_gc_warned = gc_stats.major_gc_count;
2792 sgen_client_description_for_internal_mem_type (int type)
2795 case INTERNAL_MEM_EPHEMERON_LINK: return "ephemeron-link";
2802 sgen_client_pre_collection_checks (void)
2804 if (sgen_mono_xdomain_checks) {
2805 sgen_clear_nursery_fragments ();
2806 sgen_check_for_xdomain_refs ();
2811 sgen_client_vtable_is_inited (MonoVTable *vt)
2813 return vt->klass->inited;
2817 sgen_client_vtable_get_namespace (MonoVTable *vt)
2819 return vt->klass->name_space;
2823 sgen_client_vtable_get_name (MonoVTable *vt)
2825 return vt->klass->name;
2833 sgen_client_init (void)
2836 MonoThreadInfoCallbacks cb;
2838 cb.thread_register = sgen_thread_register;
2839 cb.thread_detach = sgen_thread_detach;
2840 cb.thread_unregister = sgen_thread_unregister;
2841 cb.thread_attach = sgen_thread_attach;
2842 cb.mono_method_is_critical = (gboolean (*)(void *))is_critical_method;
2843 cb.mono_thread_in_critical_region = thread_in_critical_region;
2845 mono_threads_init (&cb, sizeof (SgenThreadInfo));
2847 ///* Keep this the default for now */
2848 /* Precise marking is broken on all supported targets. Disable until fixed. */
2849 conservative_stack_mark = TRUE;
2851 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
2853 mono_sgen_init_stw ();
2855 #ifndef HAVE_KW_THREAD
2856 mono_native_tls_alloc (&thread_info_key, NULL);
2857 #if defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
2859 * CEE_MONO_TLS requires the tls offset, not the key, so the code below only works on darwin,
2860 * where the two are the same.
2862 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, thread_info_key);
2866 int tls_offset = -1;
2867 MONO_THREAD_VAR_OFFSET (sgen_thread_info, tls_offset);
2868 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, tls_offset);
2873 * This needs to happen before any internal allocations because
2874 * it inits the small id which is required for hazard pointer
2879 mono_gc_register_thread (&dummy);
2883 sgen_client_handle_gc_param (const char *opt)
2885 if (g_str_has_prefix (opt, "stack-mark=")) {
2886 opt = strchr (opt, '=') + 1;
2887 if (!strcmp (opt, "precise")) {
2888 conservative_stack_mark = FALSE;
2889 } else if (!strcmp (opt, "conservative")) {
2890 conservative_stack_mark = TRUE;
2892 sgen_env_var_error (MONO_GC_PARAMS_NAME, conservative_stack_mark ? "Using `conservative`." : "Using `precise`.",
2893 "Invalid value `%s` for `stack-mark` option, possible values are: `precise`, `conservative`.", opt);
2895 } else if (g_str_has_prefix (opt, "bridge-implementation=")) {
2896 opt = strchr (opt, '=') + 1;
2897 sgen_set_bridge_implementation (opt);
2898 } else if (g_str_has_prefix (opt, "toggleref-test")) {
2899 /* FIXME: This should probably in MONO_GC_DEBUG */
2900 sgen_register_test_toggleref_callback ();
2908 sgen_client_print_gc_params_usage (void)
2910 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
2914 sgen_client_handle_gc_debug (const char *opt)
2916 if (!strcmp (opt, "xdomain-checks")) {
2917 sgen_mono_xdomain_checks = TRUE;
2918 } else if (!strcmp (opt, "do-not-finalize")) {
2919 mono_do_not_finalize = TRUE;
2920 } else if (g_str_has_prefix (opt, "do-not-finalize=")) {
2921 opt = strchr (opt, '=') + 1;
2922 mono_do_not_finalize = TRUE;
2923 mono_do_not_finalize_class_names = g_strsplit (opt, ",", 0);
2924 } else if (!strcmp (opt, "log-finalizers")) {
2925 log_finalizers = TRUE;
2926 } else if (!strcmp (opt, "no-managed-allocator")) {
2927 sgen_set_use_managed_allocator (FALSE);
2928 } else if (!sgen_bridge_handle_gc_debug (opt)) {
2935 sgen_client_print_gc_debug_usage (void)
2937 fprintf (stderr, " xdomain-checks\n");
2938 fprintf (stderr, " do-not-finalize\n");
2939 fprintf (stderr, " log-finalizers\n");
2940 fprintf (stderr, " no-managed-allocator\n");
2941 sgen_bridge_print_gc_debug_usage ();
2946 sgen_client_get_provenance (void)
2948 #ifdef SGEN_OBJECT_PROVENANCE
2949 MonoGCCallbacks *cb = mono_gc_get_gc_callbacks ();
2950 gpointer (*get_provenance_func) (void);
2953 get_provenance_func = cb->get_provenance_func;
2954 if (get_provenance_func)
2955 return get_provenance_func ();
2963 sgen_client_describe_invalid_pointer (GCObject *ptr)
2965 sgen_bridge_describe_pointer (ptr);
2968 static gboolean gc_inited;
2971 mono_gc_base_init (void)
2976 mono_counters_init ();
2978 #ifdef HEAVY_STATISTICS
2979 mono_counters_register ("los marked cards", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_marked_cards);
2980 mono_counters_register ("los array cards scanned ", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_cards);
2981 mono_counters_register ("los array remsets", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_remsets);
2983 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_set_arrayref);
2984 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_value_copy);
2985 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_object_copy);
2990 if (nursery_canaries_enabled ())
2991 sgen_set_use_managed_allocator (FALSE);
2993 #if defined(HAVE_KW_THREAD)
2994 /* This can happen with using libmonosgen.so */
2995 if (mono_tls_key_get_offset (TLS_KEY_SGEN_TLAB_NEXT_ADDR) == -1)
2996 sgen_set_use_managed_allocator (FALSE);
3003 mono_gc_base_cleanup (void)
3005 sgen_thread_pool_shutdown ();
3009 mono_gc_is_null (void)