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)
535 sgen_finalize_if (object_in_domain_predicate, domain);
539 mono_gc_suspend_finalizers (void)
541 sgen_set_suspend_finalizers ();
548 typedef struct _EphemeronLinkNode EphemeronLinkNode;
550 struct _EphemeronLinkNode {
551 EphemeronLinkNode *next;
560 static EphemeronLinkNode *ephemeron_list;
562 /* LOCKING: requires that the GC lock is held */
564 null_ephemerons_for_domain (MonoDomain *domain)
566 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
569 MonoObject *object = (MonoObject*)current->array;
572 SGEN_ASSERT (0, object->vtable, "Can't have objects without vtables.");
574 if (object && object->vtable->domain == domain) {
575 EphemeronLinkNode *tmp = current;
578 prev->next = current->next;
580 ephemeron_list = current->next;
582 current = current->next;
583 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
586 current = current->next;
591 /* LOCKING: requires that the GC lock is held */
593 sgen_client_clear_unreachable_ephemerons (ScanCopyContext ctx)
595 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
596 SgenGrayQueue *queue = ctx.queue;
597 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
598 Ephemeron *cur, *array_end;
602 MonoArray *array = current->array;
604 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
605 EphemeronLinkNode *tmp = current;
607 SGEN_LOG (5, "Dead Ephemeron array at %p", array);
610 prev->next = current->next;
612 ephemeron_list = current->next;
614 current = current->next;
615 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
620 copy_func ((GCObject**)&array, queue);
621 current->array = array;
623 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", array);
625 cur = mono_array_addr (array, Ephemeron, 0);
626 array_end = cur + mono_array_length_fast (array);
627 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
629 for (; cur < array_end; ++cur) {
630 GCObject *key = cur->key;
632 if (!key || key == tombstone)
635 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
636 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
637 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
639 if (!sgen_is_object_alive_for_current_gen (key)) {
640 cur->key = tombstone;
646 current = current->next;
651 LOCKING: requires that the GC lock is held
653 Limitations: We scan all ephemerons on every collection since the current design doesn't allow for a simple nursery/mature split.
656 sgen_client_mark_ephemerons (ScanCopyContext ctx)
658 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
659 SgenGrayQueue *queue = ctx.queue;
660 gboolean nothing_marked = TRUE;
661 EphemeronLinkNode *current = ephemeron_list;
662 Ephemeron *cur, *array_end;
665 for (current = ephemeron_list; current; current = current->next) {
666 MonoArray *array = current->array;
667 SGEN_LOG (5, "Ephemeron array at %p", array);
669 /*It has to be alive*/
670 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
671 SGEN_LOG (5, "\tnot reachable");
675 copy_func ((GCObject**)&array, queue);
677 cur = mono_array_addr (array, Ephemeron, 0);
678 array_end = cur + mono_array_length_fast (array);
679 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
681 for (; cur < array_end; ++cur) {
682 GCObject *key = cur->key;
684 if (!key || key == tombstone)
687 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
688 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
689 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
691 if (sgen_is_object_alive_for_current_gen (key)) {
692 GCObject *value = cur->value;
694 copy_func (&cur->key, queue);
696 if (!sgen_is_object_alive_for_current_gen (value))
697 nothing_marked = FALSE;
698 copy_func (&cur->value, queue);
704 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
705 return nothing_marked;
709 mono_gc_ephemeron_array_add (MonoObject *obj)
711 EphemeronLinkNode *node;
715 node = (EphemeronLinkNode *)sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
720 node->array = (MonoArray*)obj;
721 node->next = ephemeron_list;
722 ephemeron_list = node;
724 SGEN_LOG (5, "Registered ephemeron array %p", obj);
735 mono_gc_set_current_thread_appdomain (MonoDomain *domain)
737 SgenThreadInfo *info = mono_thread_info_current ();
739 /* Could be called from sgen_thread_unregister () with a NULL info */
742 info->client_info.stopped_domain = domain;
747 need_remove_object_for_domain (GCObject *start, MonoDomain *domain)
749 if (mono_object_domain (start) == domain) {
750 SGEN_LOG (4, "Need to cleanup object %p", start);
751 binary_protocol_cleanup (start, (gpointer)SGEN_LOAD_VTABLE (start), sgen_safe_object_get_size ((GCObject*)start));
758 process_object_for_domain_clearing (GCObject *start, MonoDomain *domain)
760 MonoVTable *vt = SGEN_LOAD_VTABLE (start);
761 if (vt->klass == mono_defaults.internal_thread_class)
762 g_assert (mono_object_domain (start) == mono_get_root_domain ());
763 /* The object could be a proxy for an object in the domain
765 #ifndef DISABLE_REMOTING
766 if (mono_defaults.real_proxy_class->supertypes && mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
767 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
769 /* The server could already have been zeroed out, so
770 we need to check for that, too. */
771 if (server && (!SGEN_LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
772 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
773 ((MonoRealProxy*)start)->unwrapped_server = NULL;
780 clear_domain_process_object (GCObject *obj, MonoDomain *domain)
784 process_object_for_domain_clearing (obj, domain);
785 remove = need_remove_object_for_domain (obj, domain);
787 if (remove && obj->synchronisation) {
788 guint32 dislink = mono_monitor_get_object_monitor_gchandle (obj);
790 mono_gchandle_free (dislink);
797 clear_domain_process_minor_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
799 if (clear_domain_process_object (obj, domain)) {
800 CANARIFY_SIZE (size);
801 memset (obj, 0, size);
806 clear_domain_process_major_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
808 clear_domain_process_object (obj, domain);
812 clear_domain_free_major_non_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
814 if (need_remove_object_for_domain (obj, domain))
815 major_collector.free_non_pinned_object (obj, size);
819 clear_domain_free_major_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
821 if (need_remove_object_for_domain (obj, domain))
822 major_collector.free_pinned_object (obj, size);
826 * When appdomains are unloaded we can easily remove objects that have finalizers,
827 * but all the others could still be present in random places on the heap.
828 * We need a sweep to get rid of them even though it's going to be costly
830 * The reason we need to remove them is because we access the vtable and class
831 * structures to know the object size and the reference bitmap: once the domain is
832 * unloaded the point to random memory.
835 mono_gc_clear_domain (MonoDomain * domain)
837 LOSObject *bigobj, *prev;
842 binary_protocol_domain_unload_begin (domain);
846 if (sgen_concurrent_collection_in_progress ())
847 sgen_perform_collection (0, GENERATION_OLD, "clear domain", TRUE, FALSE);
848 SGEN_ASSERT (0, !sgen_concurrent_collection_in_progress (), "We just ordered a synchronous collection. Why are we collecting concurrently?");
850 major_collector.finish_sweeping ();
852 sgen_process_fin_stage_entries ();
854 sgen_clear_nursery_fragments ();
856 if (sgen_mono_xdomain_checks && domain != mono_get_root_domain ()) {
857 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
858 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
859 sgen_check_for_xdomain_refs ();
862 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
863 to memory returned to the OS.*/
864 null_ephemerons_for_domain (domain);
865 sgen_null_links_for_domain (domain);
867 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
868 sgen_remove_finalizers_if (object_in_domain_predicate, domain, i);
870 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
871 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE, TRUE);
873 /* We need two passes over major and large objects because
874 freeing such objects might give their memory back to the OS
875 (in the case of large objects) or obliterate its vtable
876 (pinned objects with major-copying or pinned and non-pinned
877 objects with major-mark&sweep), but we might need to
878 dereference a pointer from an object to another object if
879 the first object is a proxy. */
880 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
881 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
882 clear_domain_process_object ((GCObject*)bigobj->data, domain);
885 for (bigobj = los_object_list; bigobj;) {
886 if (need_remove_object_for_domain ((GCObject*)bigobj->data, domain)) {
887 LOSObject *to_free = bigobj;
889 prev->next = bigobj->next;
891 los_object_list = bigobj->next;
892 bigobj = bigobj->next;
893 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
894 sgen_los_free_object (to_free);
898 bigobj = bigobj->next;
900 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
901 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
903 if (domain == mono_get_root_domain ()) {
904 sgen_pin_stats_report ();
905 sgen_object_layout_dump (stdout);
908 sgen_restart_world (0);
910 binary_protocol_domain_unload_end (domain);
911 binary_protocol_flush_buffers (FALSE);
920 static gboolean alloc_events = FALSE;
923 mono_gc_enable_alloc_events (void)
929 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
931 MonoObject *obj = sgen_alloc_obj (vtable, size);
933 if (G_UNLIKELY (alloc_events)) {
935 mono_profiler_allocation (obj);
942 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
944 MonoObject *obj = sgen_alloc_obj_pinned (vtable, size);
946 if (G_UNLIKELY (alloc_events)) {
948 mono_profiler_allocation (obj);
955 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
957 MonoObject *obj = sgen_alloc_obj_mature (vtable, size);
959 if (G_UNLIKELY (alloc_events)) {
961 mono_profiler_allocation (obj);
968 mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
970 /* FIXME: do a single allocation */
971 void *res = calloc (1, size);
974 if (!mono_gc_register_root ((char *)res, size, descr, source, msg)) {
982 mono_gc_free_fixed (void* addr)
984 mono_gc_deregister_root ((char *)addr);
992 static MonoMethod* alloc_method_cache [ATYPE_NUM];
993 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
994 static gboolean use_managed_allocator = TRUE;
996 #ifdef MANAGED_ALLOCATION
998 #if defined(HAVE_KW_THREAD) || defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
1000 // Cache the SgenThreadInfo pointer in a local 'var'.
1001 #define EMIT_TLS_ACCESS_VAR(mb, var) \
1003 var = mono_mb_add_local ((mb), &mono_defaults.int_class->byval_arg); \
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_THREAD_INFO); \
1007 mono_mb_emit_stloc ((mb), (var)); \
1010 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, var) \
1012 mono_mb_emit_ldloc ((mb), (var)); \
1013 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenClientThreadInfo, in_critical_region)); \
1014 mono_mb_emit_byte ((mb), CEE_ADD); \
1017 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, var) do { \
1018 mono_mb_emit_ldloc ((mb), (var)); \
1019 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_next)); \
1020 mono_mb_emit_byte ((mb), CEE_ADD); \
1023 #define EMIT_TLS_ACCESS_TEMP_END(mb, var) do { \
1024 mono_mb_emit_ldloc ((mb), (var)); \
1025 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_temp_end)); \
1026 mono_mb_emit_byte ((mb), CEE_ADD); \
1027 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1031 #define EMIT_TLS_ACCESS_VAR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1032 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1033 #define EMIT_TLS_ACCESS_TEMP_END(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1034 #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)
1038 /* FIXME: Do this in the JIT, where specialized allocation sequences can be created
1039 * for each class. This is currently not easy to do, as it is hard to generate basic
1040 * blocks + branches, but it is easy with the linear IL codebase.
1042 * For this to work we'd need to solve the TLAB race, first. Now we
1043 * require the allocator to be in a few known methods to make sure
1044 * that they are executed atomically via the restart mechanism.
1047 create_allocator (int atype, ManagedAllocatorVariant variant)
1049 int p_var, size_var, thread_var G_GNUC_UNUSED;
1050 gboolean slowpath = variant == MANAGED_ALLOCATOR_SLOW_PATH;
1051 guint32 slowpath_branch, max_size_branch;
1052 MonoMethodBuilder *mb;
1054 MonoMethodSignature *csig;
1055 static gboolean registered = FALSE;
1056 int tlab_next_addr_var, new_next_var;
1057 const char *name = NULL;
1062 mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
1063 mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
1064 mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE);
1068 if (atype == ATYPE_SMALL) {
1069 name = slowpath ? "SlowAllocSmall" : "AllocSmall";
1070 } else if (atype == ATYPE_NORMAL) {
1071 name = slowpath ? "SlowAlloc" : "Alloc";
1072 } else if (atype == ATYPE_VECTOR) {
1073 name = slowpath ? "SlowAllocVector" : "AllocVector";
1074 } else if (atype == ATYPE_STRING) {
1075 name = slowpath ? "SlowAllocString" : "AllocString";
1077 g_assert_not_reached ();
1080 if (atype == ATYPE_NORMAL)
1085 csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
1086 if (atype == ATYPE_STRING) {
1087 csig->ret = &mono_defaults.string_class->byval_arg;
1088 csig->params [0] = &mono_defaults.int_class->byval_arg;
1089 csig->params [1] = &mono_defaults.int32_class->byval_arg;
1091 csig->ret = &mono_defaults.object_class->byval_arg;
1092 for (i = 0; i < num_params; i++)
1093 csig->params [i] = &mono_defaults.int_class->byval_arg;
1096 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
1103 mono_mb_emit_ldarg (mb, 0);
1104 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1107 mono_mb_emit_ldarg (mb, 0);
1108 mono_mb_emit_ldarg (mb, 1);
1109 mono_mb_emit_icall (mb, ves_icall_array_new_specific);
1112 mono_mb_emit_ldarg (mb, 1);
1113 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1116 g_assert_not_reached ();
1123 * Tls access might call foreign code or code without jinfo. This can
1124 * only happen if we are outside of the critical region.
1126 EMIT_TLS_ACCESS_VAR (mb, thread_var);
1128 size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1129 if (atype == ATYPE_SMALL) {
1130 /* size_var = size_arg */
1131 mono_mb_emit_ldarg (mb, 1);
1132 mono_mb_emit_stloc (mb, size_var);
1133 } else if (atype == ATYPE_NORMAL) {
1134 /* size = vtable->klass->instance_size; */
1135 mono_mb_emit_ldarg (mb, 0);
1136 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1137 mono_mb_emit_byte (mb, CEE_ADD);
1138 mono_mb_emit_byte (mb, CEE_LDIND_I);
1139 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, instance_size));
1140 mono_mb_emit_byte (mb, CEE_ADD);
1141 /* FIXME: assert instance_size stays a 4 byte integer */
1142 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1143 mono_mb_emit_byte (mb, CEE_CONV_I);
1144 mono_mb_emit_stloc (mb, size_var);
1145 } else if (atype == ATYPE_VECTOR) {
1146 MonoExceptionClause *clause;
1147 int pos, pos_leave, pos_error;
1148 MonoClass *oom_exc_class;
1152 * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException
1153 * n < 0 => OverflowException
1155 * We can do an unsigned comparison to catch both cases, then in the error
1156 * case compare signed to distinguish between them.
1158 mono_mb_emit_ldarg (mb, 1);
1159 mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
1160 mono_mb_emit_byte (mb, CEE_CONV_U);
1161 pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
1163 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1164 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1165 mono_mb_emit_ldarg (mb, 1);
1166 mono_mb_emit_icon (mb, 0);
1167 pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S);
1168 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1169 mono_mb_patch_short_branch (mb, pos_error);
1170 mono_mb_emit_exception (mb, "OverflowException", NULL);
1172 mono_mb_patch_short_branch (mb, pos);
1174 clause = (MonoExceptionClause *)mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
1175 clause->try_offset = mono_mb_get_label (mb);
1177 /* vtable->klass->sizes.element_size */
1178 mono_mb_emit_ldarg (mb, 0);
1179 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1180 mono_mb_emit_byte (mb, CEE_ADD);
1181 mono_mb_emit_byte (mb, CEE_LDIND_I);
1182 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, sizes));
1183 mono_mb_emit_byte (mb, CEE_ADD);
1184 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1185 mono_mb_emit_byte (mb, CEE_CONV_I);
1188 mono_mb_emit_ldarg (mb, 1);
1189 mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
1190 /* + sizeof (MonoArray) */
1191 mono_mb_emit_icon (mb, MONO_SIZEOF_MONO_ARRAY);
1192 mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
1193 mono_mb_emit_stloc (mb, size_var);
1195 pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);
1198 clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
1199 clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
1200 clause->data.catch_class = mono_class_load_from_name (mono_defaults.corlib,
1201 "System", "OverflowException");
1202 clause->handler_offset = mono_mb_get_label (mb);
1204 oom_exc_class = mono_class_load_from_name (mono_defaults.corlib,
1205 "System", "OutOfMemoryException");
1206 ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
1209 mono_mb_emit_byte (mb, CEE_POP);
1210 mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
1211 mono_mb_emit_byte (mb, CEE_THROW);
1213 clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
1214 mono_mb_set_clauses (mb, 1, clause);
1215 mono_mb_patch_branch (mb, pos_leave);
1217 } else if (atype == ATYPE_STRING) {
1221 * a string allocator method takes the args: (vtable, len)
1223 * bytes = offsetof (MonoString, chars) + ((len + 1) * 2)
1227 * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1231 * offsetof (MonoString, chars) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1232 * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - offsetof (MonoString, chars)) / 2 - 1
1234 mono_mb_emit_ldarg (mb, 1);
1235 mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - MONO_STRUCT_OFFSET (MonoString, chars)) / 2 - 1);
1236 pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
1238 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1239 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1240 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1241 mono_mb_patch_short_branch (mb, pos);
1243 mono_mb_emit_ldarg (mb, 1);
1244 mono_mb_emit_icon (mb, 1);
1245 mono_mb_emit_byte (mb, MONO_CEE_SHL);
1246 //WE manually fold the above + 2 here
1247 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, chars) + 2);
1248 mono_mb_emit_byte (mb, CEE_ADD);
1249 mono_mb_emit_stloc (mb, size_var);
1251 g_assert_not_reached ();
1254 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1255 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1256 mono_mb_emit_byte (mb, CEE_LDC_I4_1);
1257 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1258 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1259 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1262 /* size += ALLOC_ALIGN - 1; */
1263 mono_mb_emit_ldloc (mb, size_var);
1264 mono_mb_emit_icon (mb, SGEN_ALLOC_ALIGN - 1);
1265 mono_mb_emit_byte (mb, CEE_ADD);
1266 /* size &= ~(ALLOC_ALIGN - 1); */
1267 mono_mb_emit_icon (mb, ~(SGEN_ALLOC_ALIGN - 1));
1268 mono_mb_emit_byte (mb, CEE_AND);
1269 mono_mb_emit_stloc (mb, size_var);
1271 /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
1272 if (atype != ATYPE_SMALL) {
1273 mono_mb_emit_ldloc (mb, size_var);
1274 mono_mb_emit_icon (mb, SGEN_MAX_SMALL_OBJ_SIZE);
1275 max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
1279 * We need to modify tlab_next, but the JIT only supports reading, so we read
1280 * another tls var holding its address instead.
1283 /* tlab_next_addr (local) = tlab_next_addr (TLS var) */
1284 tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1285 EMIT_TLS_ACCESS_NEXT_ADDR (mb, thread_var);
1286 mono_mb_emit_stloc (mb, tlab_next_addr_var);
1288 /* p = (void**)tlab_next; */
1289 p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1290 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1291 mono_mb_emit_byte (mb, CEE_LDIND_I);
1292 mono_mb_emit_stloc (mb, p_var);
1294 /* new_next = (char*)p + size; */
1295 new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1296 mono_mb_emit_ldloc (mb, p_var);
1297 mono_mb_emit_ldloc (mb, size_var);
1298 mono_mb_emit_byte (mb, CEE_CONV_I);
1299 mono_mb_emit_byte (mb, CEE_ADD);
1300 mono_mb_emit_stloc (mb, new_next_var);
1302 /* if (G_LIKELY (new_next < tlab_temp_end)) */
1303 mono_mb_emit_ldloc (mb, new_next_var);
1304 EMIT_TLS_ACCESS_TEMP_END (mb, thread_var);
1305 slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1308 if (atype != ATYPE_SMALL)
1309 mono_mb_patch_short_branch (mb, max_size_branch);
1311 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1312 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1314 * We are no longer in a critical section. We need to do this before calling
1315 * to unmanaged land in order to avoid stw deadlocks since unmanaged code
1318 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1319 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1320 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1321 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1322 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1323 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1326 /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
1327 mono_mb_emit_ldarg (mb, 0);
1328 mono_mb_emit_ldloc (mb, size_var);
1329 if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
1330 mono_mb_emit_icall (mb, mono_gc_alloc_obj);
1331 } else if (atype == ATYPE_VECTOR) {
1332 mono_mb_emit_ldarg (mb, 1);
1333 mono_mb_emit_icall (mb, mono_gc_alloc_vector);
1334 } else if (atype == ATYPE_STRING) {
1335 mono_mb_emit_ldarg (mb, 1);
1336 mono_mb_emit_icall (mb, mono_gc_alloc_string);
1338 g_assert_not_reached ();
1340 mono_mb_emit_byte (mb, CEE_RET);
1343 mono_mb_patch_short_branch (mb, slowpath_branch);
1345 /* FIXME: Memory barrier */
1347 /* tlab_next = new_next */
1348 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1349 mono_mb_emit_ldloc (mb, new_next_var);
1350 mono_mb_emit_byte (mb, CEE_STIND_I);
1353 mono_mb_emit_ldloc (mb, p_var);
1354 mono_mb_emit_ldarg (mb, 0);
1355 mono_mb_emit_byte (mb, CEE_STIND_I);
1357 if (atype == ATYPE_VECTOR) {
1358 /* arr->max_length = max_length; */
1359 mono_mb_emit_ldloc (mb, p_var);
1360 mono_mb_emit_ldflda (mb, MONO_STRUCT_OFFSET (MonoArray, max_length));
1361 mono_mb_emit_ldarg (mb, 1);
1362 #ifdef MONO_BIG_ARRAYS
1363 mono_mb_emit_byte (mb, CEE_STIND_I);
1365 mono_mb_emit_byte (mb, CEE_STIND_I4);
1367 } else if (atype == ATYPE_STRING) {
1368 /* need to set length and clear the last char */
1369 /* s->length = len; */
1370 mono_mb_emit_ldloc (mb, p_var);
1371 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, length));
1372 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1373 mono_mb_emit_ldarg (mb, 1);
1374 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1377 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1378 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1379 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1380 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1381 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1383 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1384 mono_mb_emit_byte (mb, CEE_MONO_MEMORY_BARRIER);
1387 We must make sure both vtable and max_length are globaly visible before returning to managed land.
1389 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_REL);
1392 mono_mb_emit_ldloc (mb, p_var);
1395 mono_mb_emit_byte (mb, CEE_RET);
1398 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1399 info->d.alloc.gc_name = "sgen";
1400 info->d.alloc.alloc_type = atype;
1403 mb->init_locals = FALSE;
1406 res = mono_mb_create (mb, csig, 8, info);
1415 mono_gc_get_aligned_size_for_allocator (int size)
1417 return SGEN_ALIGN_UP (size);
1421 * Generate an allocator method implementing the fast path of mono_gc_alloc_obj ().
1422 * The signature of the called method is:
1423 * object allocate (MonoVTable *vtable)
1426 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1428 #ifdef MANAGED_ALLOCATION
1429 if (collect_before_allocs)
1431 if (!mono_runtime_has_tls_get ())
1433 if (klass->instance_size > tlab_size)
1435 if (known_instance_size && ALIGN_TO (klass->instance_size, SGEN_ALLOC_ALIGN) >= SGEN_MAX_SMALL_OBJ_SIZE)
1437 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1441 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1443 if (klass->byval_arg.type == MONO_TYPE_STRING)
1444 return mono_gc_get_managed_allocator_by_type (ATYPE_STRING, MANAGED_ALLOCATOR_REGULAR);
1445 /* Generic classes have dynamic field and can go above MAX_SMALL_OBJ_SIZE. */
1446 if (known_instance_size)
1447 return mono_gc_get_managed_allocator_by_type (ATYPE_SMALL, MANAGED_ALLOCATOR_REGULAR);
1449 return mono_gc_get_managed_allocator_by_type (ATYPE_NORMAL, MANAGED_ALLOCATOR_REGULAR);
1456 mono_gc_get_managed_array_allocator (MonoClass *klass)
1458 #ifdef MANAGED_ALLOCATION
1459 if (klass->rank != 1)
1461 if (!mono_runtime_has_tls_get ())
1463 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1465 if (has_per_allocation_action)
1467 g_assert (!mono_class_has_finalizer (klass) && !mono_class_is_marshalbyref (klass));
1469 return mono_gc_get_managed_allocator_by_type (ATYPE_VECTOR, MANAGED_ALLOCATOR_REGULAR);
1476 sgen_set_use_managed_allocator (gboolean flag)
1478 use_managed_allocator = flag;
1482 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1484 #ifdef MANAGED_ALLOCATION
1488 if (variant == MANAGED_ALLOCATOR_REGULAR && !use_managed_allocator)
1491 if (variant == MANAGED_ALLOCATOR_REGULAR && !mono_runtime_has_tls_get ())
1495 case MANAGED_ALLOCATOR_REGULAR: cache = alloc_method_cache; break;
1496 case MANAGED_ALLOCATOR_SLOW_PATH: cache = slowpath_alloc_method_cache; break;
1497 default: g_assert_not_reached (); break;
1500 res = cache [atype];
1504 res = create_allocator (atype, variant);
1506 if (cache [atype]) {
1507 mono_free_method (res);
1508 res = cache [atype];
1510 mono_memory_barrier ();
1511 cache [atype] = res;
1522 mono_gc_get_managed_allocator_types (void)
1528 sgen_is_managed_allocator (MonoMethod *method)
1532 for (i = 0; i < ATYPE_NUM; ++i)
1533 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1539 sgen_has_managed_allocator (void)
1543 for (i = 0; i < ATYPE_NUM; ++i)
1544 if (alloc_method_cache [i] || slowpath_alloc_method_cache [i])
1550 * Cardtable scanning
1553 #define MWORD_MASK (sizeof (mword) - 1)
1556 find_card_offset (mword card)
1558 /*XXX Use assembly as this generates some pretty bad code */
1559 #if defined(__i386__) && defined(__GNUC__)
1560 return (__builtin_ffs (card) - 1) / 8;
1561 #elif defined(__x86_64__) && defined(__GNUC__)
1562 return (__builtin_ffsll (card) - 1) / 8;
1563 #elif defined(__s390x__)
1564 return (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1567 guint8 *ptr = (guint8 *) &card;
1568 for (i = 0; i < sizeof (mword); ++i) {
1577 find_next_card (guint8 *card_data, guint8 *end)
1579 mword *cards, *cards_end;
1582 while ((((mword)card_data) & MWORD_MASK) && card_data < end) {
1588 if (card_data == end)
1591 cards = (mword*)card_data;
1592 cards_end = (mword*)((mword)end & ~MWORD_MASK);
1593 while (cards < cards_end) {
1596 return (guint8*)cards + find_card_offset (card);
1600 card_data = (guint8*)cards_end;
1601 while (card_data < end) {
1610 #define ARRAY_OBJ_INDEX(ptr,array,elem_size) (((char*)(ptr) - ((char*)(array) + G_STRUCT_OFFSET (MonoArray, vector))) / (elem_size))
1613 sgen_client_cardtable_scan_object (GCObject *obj, mword block_obj_size, guint8 *cards, ScanCopyContext ctx)
1615 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
1616 MonoClass *klass = vt->klass;
1618 SGEN_ASSERT (0, SGEN_VTABLE_HAS_REFERENCES (vt), "Why would we ever call this on reference-free objects?");
1621 MonoArray *arr = (MonoArray*)obj;
1622 guint8 *card_data, *card_base;
1623 guint8 *card_data_end;
1624 char *obj_start = (char *)sgen_card_table_align_pointer (obj);
1626 mword obj_size = sgen_mono_array_size (vt, arr, &bounds_size, sgen_vtable_get_descriptor (vt));
1627 /* We don't want to scan the bounds entries at the end of multidimensional arrays */
1628 char *obj_end = (char*)obj + obj_size - bounds_size;
1630 size_t extra_idx = 0;
1632 mword desc = (mword)klass->element_class->gc_descr;
1633 int elem_size = mono_array_element_size (klass);
1635 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1636 guint8 *overflow_scan_end = NULL;
1639 #ifdef SGEN_OBJECT_LAYOUT_STATISTICS
1640 if (klass->element_class->valuetype)
1641 sgen_object_layout_scanned_vtype_array ();
1643 sgen_object_layout_scanned_ref_array ();
1649 card_data = sgen_card_table_get_card_scan_address ((mword)obj);
1651 card_base = card_data;
1652 card_count = sgen_card_table_number_of_cards_in_range ((mword)obj, obj_size);
1653 card_data_end = card_data + card_count;
1656 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1657 /*Check for overflow and if so, setup to scan in two steps*/
1658 if (!cards && card_data_end >= SGEN_SHADOW_CARDTABLE_END) {
1659 overflow_scan_end = sgen_shadow_cardtable + (card_data_end - SGEN_SHADOW_CARDTABLE_END);
1660 card_data_end = SGEN_SHADOW_CARDTABLE_END;
1666 card_data = find_next_card (card_data, card_data_end);
1667 for (; card_data < card_data_end; card_data = find_next_card (card_data + 1, card_data_end)) {
1669 size_t idx = (card_data - card_base) + extra_idx;
1670 char *start = (char*)(obj_start + idx * CARD_SIZE_IN_BYTES);
1671 char *card_end = start + CARD_SIZE_IN_BYTES;
1672 char *first_elem, *elem;
1674 HEAVY_STAT (++los_marked_cards);
1677 sgen_card_table_prepare_card_for_scanning (card_data);
1679 card_end = MIN (card_end, obj_end);
1681 if (start <= (char*)arr->vector)
1684 index = ARRAY_OBJ_INDEX (start, obj, elem_size);
1686 elem = first_elem = (char*)mono_array_addr_with_size_fast ((MonoArray*)obj, elem_size, index);
1687 if (klass->element_class->valuetype) {
1688 ScanVTypeFunc scan_vtype_func = ctx.ops->scan_vtype;
1690 for (; elem < card_end; elem += elem_size)
1691 scan_vtype_func (obj, elem, desc, ctx.queue BINARY_PROTOCOL_ARG (elem_size));
1693 ScanPtrFieldFunc scan_ptr_field_func = ctx.ops->scan_ptr_field;
1695 HEAVY_STAT (++los_array_cards);
1696 for (; elem < card_end; elem += SIZEOF_VOID_P)
1697 scan_ptr_field_func (obj, (GCObject**)elem, ctx.queue);
1700 binary_protocol_card_scan (first_elem, elem - first_elem);
1703 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1704 if (overflow_scan_end) {
1705 extra_idx = card_data - card_base;
1706 card_base = card_data = sgen_shadow_cardtable;
1707 card_data_end = overflow_scan_end;
1708 overflow_scan_end = NULL;
1719 * Array and string allocation
1723 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
1728 if (!SGEN_CAN_ALIGN_UP (size))
1731 #ifndef DISABLE_CRITICAL_REGION
1732 ENTER_CRITICAL_REGION;
1733 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1735 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1736 arr->max_length = (mono_array_size_t)max_length;
1737 EXIT_CRITICAL_REGION;
1740 EXIT_CRITICAL_REGION;
1745 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1746 if (G_UNLIKELY (!arr)) {
1751 arr->max_length = (mono_array_size_t)max_length;
1756 if (G_UNLIKELY (alloc_events))
1757 mono_profiler_allocation (&arr->obj);
1759 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Vector has incorrect size.");
1764 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
1767 MonoArrayBounds *bounds;
1770 if (!SGEN_CAN_ALIGN_UP (size))
1773 #ifndef DISABLE_CRITICAL_REGION
1774 ENTER_CRITICAL_REGION;
1775 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1777 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1778 arr->max_length = (mono_array_size_t)max_length;
1780 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1781 arr->bounds = bounds;
1782 EXIT_CRITICAL_REGION;
1785 EXIT_CRITICAL_REGION;
1790 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1791 if (G_UNLIKELY (!arr)) {
1796 arr->max_length = (mono_array_size_t)max_length;
1798 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1799 arr->bounds = bounds;
1804 if (G_UNLIKELY (alloc_events))
1805 mono_profiler_allocation (&arr->obj);
1807 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Array has incorrect size.");
1812 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
1817 if (!SGEN_CAN_ALIGN_UP (size))
1820 #ifndef DISABLE_CRITICAL_REGION
1821 ENTER_CRITICAL_REGION;
1822 str = (MonoString*)sgen_try_alloc_obj_nolock (vtable, size);
1824 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1826 EXIT_CRITICAL_REGION;
1829 EXIT_CRITICAL_REGION;
1834 str = (MonoString*)sgen_alloc_obj_nolock (vtable, size);
1835 if (G_UNLIKELY (!str)) {
1845 if (G_UNLIKELY (alloc_events))
1846 mono_profiler_allocation (&str->object);
1856 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1858 mono_unichar2 *new_end = str->chars + new_length;
1860 /* zero the discarded string. This null-delimits the string and allows
1861 * the space to be reclaimed by SGen. */
1863 if (nursery_canaries_enabled () && sgen_ptr_in_nursery (str)) {
1864 CHECK_CANARY_FOR_OBJECT ((GCObject*)str, TRUE);
1865 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2) + CANARY_SIZE);
1866 memcpy (new_end + 1 , CANARY_STRING, CANARY_SIZE);
1868 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1871 str->length = new_length;
1878 #define GC_ROOT_NUM 32
1880 int count; /* must be the first field */
1881 void *objects [GC_ROOT_NUM];
1882 int root_types [GC_ROOT_NUM];
1883 uintptr_t extra_info [GC_ROOT_NUM];
1887 notify_gc_roots (GCRootReport *report)
1891 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
1896 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
1898 if (report->count == GC_ROOT_NUM)
1899 notify_gc_roots (report);
1900 report->objects [report->count] = object;
1901 report->root_types [report->count] = rtype;
1902 report->extra_info [report->count++] = (uintptr_t)SGEN_LOAD_VTABLE (object)->klass;
1906 sgen_client_nursery_objects_pinned (void **definitely_pinned, int count)
1908 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1909 GCRootReport report;
1912 for (idx = 0; idx < count; ++idx)
1913 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1914 notify_gc_roots (&report);
1919 report_finalizer_roots_from_queue (SgenPointerQueue *queue)
1921 GCRootReport report;
1925 for (i = 0; i < queue->next_slot; ++i) {
1926 void *obj = queue->data [i];
1929 add_profile_gc_root (&report, obj, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1931 notify_gc_roots (&report);
1935 report_finalizer_roots (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
1937 report_finalizer_roots_from_queue (fin_ready_queue);
1938 report_finalizer_roots_from_queue (critical_fin_queue);
1941 static GCRootReport *root_report;
1944 single_arg_report_root (MonoObject **obj, void *gc_data)
1947 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1951 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1953 switch (desc & ROOT_DESC_TYPE_MASK) {
1954 case ROOT_DESC_BITMAP:
1955 desc >>= ROOT_DESC_TYPE_SHIFT;
1957 if ((desc & 1) && *start_root) {
1958 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1964 case ROOT_DESC_COMPLEX: {
1965 gsize *bitmap_data = (gsize *)sgen_get_complex_descriptor_bitmap (desc);
1966 gsize bwords = (*bitmap_data) - 1;
1967 void **start_run = start_root;
1969 while (bwords-- > 0) {
1970 gsize bmap = *bitmap_data++;
1971 void **objptr = start_run;
1973 if ((bmap & 1) && *objptr) {
1974 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
1979 start_run += GC_BITS_PER_WORD;
1983 case ROOT_DESC_USER: {
1984 MonoGCRootMarkFunc marker = (MonoGCRootMarkFunc)sgen_get_user_descriptor_func (desc);
1985 root_report = report;
1986 marker ((MonoObject**)start_root, single_arg_report_root, NULL);
1989 case ROOT_DESC_RUN_LEN:
1990 g_assert_not_reached ();
1992 g_assert_not_reached ();
1997 report_registered_roots_by_type (int root_type)
1999 GCRootReport report;
2003 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], void **, start_root, RootRecord *, root) {
2004 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
2005 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
2006 } SGEN_HASH_TABLE_FOREACH_END;
2007 notify_gc_roots (&report);
2011 report_registered_roots (void)
2013 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
2014 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
2018 sgen_client_collecting_minor (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2020 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2021 report_registered_roots ();
2022 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2023 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2026 static GCRootReport major_root_report;
2027 static gboolean profile_roots;
2030 sgen_client_collecting_major_1 (void)
2032 profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2033 memset (&major_root_report, 0, sizeof (GCRootReport));
2037 sgen_client_pinned_los_object (GCObject *obj)
2040 add_profile_gc_root (&major_root_report, (char*)obj, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2044 sgen_client_collecting_major_2 (void)
2047 notify_gc_roots (&major_root_report);
2049 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2050 report_registered_roots ();
2054 sgen_client_collecting_major_3 (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2056 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2057 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2060 #define MOVED_OBJECTS_NUM 64
2061 static void *moved_objects [MOVED_OBJECTS_NUM];
2062 static int moved_objects_idx = 0;
2065 mono_sgen_register_moved_object (void *obj, void *destination)
2067 g_assert (mono_profiler_events & MONO_PROFILE_GC_MOVES);
2069 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2070 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2071 moved_objects_idx = 0;
2073 moved_objects [moved_objects_idx++] = obj;
2074 moved_objects [moved_objects_idx++] = destination;
2078 mono_sgen_gc_event_moves (void)
2080 if (moved_objects_idx) {
2081 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2082 moved_objects_idx = 0;
2090 #define REFS_SIZE 128
2093 MonoGCReferences callback;
2097 MonoObject *refs [REFS_SIZE];
2098 uintptr_t offsets [REFS_SIZE];
2102 #define HANDLE_PTR(ptr,obj) do { \
2104 if (hwi->count == REFS_SIZE) { \
2105 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
2109 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
2110 hwi->refs [hwi->count++] = *(ptr); \
2115 collect_references (HeapWalkInfo *hwi, GCObject *obj, size_t size)
2117 char *start = (char*)obj;
2118 mword desc = sgen_obj_get_descriptor (obj);
2120 #include "sgen/sgen-scan-object.h"
2124 walk_references (GCObject *start, size_t size, void *data)
2126 HeapWalkInfo *hwi = (HeapWalkInfo *)data;
2129 collect_references (hwi, start, size);
2130 if (hwi->count || !hwi->called)
2131 hwi->callback (start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
2135 * mono_gc_walk_heap:
2136 * @flags: flags for future use
2137 * @callback: a function pointer called for each object in the heap
2138 * @data: a user data pointer that is passed to callback
2140 * This function can be used to iterate over all the live objects in the heap:
2141 * for each object, @callback is invoked, providing info about the object's
2142 * location in memory, its class, its size and the objects it references.
2143 * For each referenced object it's offset from the object address is
2144 * reported in the offsets array.
2145 * The object references may be buffered, so the callback may be invoked
2146 * multiple times for the same object: in all but the first call, the size
2147 * argument will be zero.
2148 * Note that this function can be only called in the #MONO_GC_EVENT_PRE_START_WORLD
2149 * profiler event handler.
2151 * Returns: a non-zero value if the GC doesn't support heap walking
2154 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
2159 hwi.callback = callback;
2162 sgen_clear_nursery_fragments ();
2163 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE, TRUE);
2165 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, walk_references, &hwi);
2166 sgen_los_iterate_objects (walk_references, &hwi);
2176 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
2178 gc_callbacks = *callbacks;
2182 mono_gc_get_gc_callbacks ()
2184 return &gc_callbacks;
2188 sgen_client_thread_register (SgenThreadInfo* info, void *stack_bottom_fallback)
2191 guint8 *staddr = NULL;
2193 #ifndef HAVE_KW_THREAD
2194 g_assert (!mono_native_tls_get_value (thread_info_key));
2195 mono_native_tls_set_value (thread_info_key, info);
2197 sgen_thread_info = info;
2200 info->client_info.skip = 0;
2201 info->client_info.stopped_ip = NULL;
2202 info->client_info.stopped_domain = NULL;
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 /* On win32, stack_start_limit should be 0, since the stack can grow dynamically */
2212 mono_thread_info_get_stack_bounds (&staddr, &stsize);
2215 info->client_info.stack_start_limit = staddr;
2217 info->client_info.stack_end = staddr + stsize;
2219 gsize stack_bottom = (gsize)stack_bottom_fallback;
2220 stack_bottom += 4095;
2221 stack_bottom &= ~4095;
2222 info->client_info.stack_end = (char*)stack_bottom;
2225 memset (&info->client_info.ctx, 0, sizeof (MonoContext));
2227 if (mono_gc_get_gc_callbacks ()->thread_attach_func)
2228 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2230 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
2232 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->client_info.stack_end);
2234 info->client_info.info.handle_stack = mono_handle_stack_alloc ();
2238 sgen_client_thread_unregister (SgenThreadInfo *p)
2240 MonoNativeThreadId tid;
2242 #ifndef HAVE_KW_THREAD
2243 mono_native_tls_set_value (thread_info_key, NULL);
2245 sgen_thread_info = NULL;
2248 tid = mono_thread_info_get_tid (p);
2250 if (p->client_info.info.runtime_thread)
2251 mono_threads_add_joinable_thread ((gpointer)tid);
2253 if (mono_gc_get_gc_callbacks ()->thread_detach_func) {
2254 mono_gc_get_gc_callbacks ()->thread_detach_func (p->client_info.runtime_data);
2255 p->client_info.runtime_data = NULL;
2258 binary_protocol_thread_unregister ((gpointer)tid);
2259 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)tid);
2261 HandleStack *handles = (HandleStack*) p->client_info.info.handle_stack;
2262 p->client_info.info.handle_stack = NULL;
2263 mono_handle_stack_free (handles);
2267 mono_gc_set_skip_thread (gboolean skip)
2269 SgenThreadInfo *info = mono_thread_info_current ();
2272 info->client_info.gc_disabled = skip;
2277 is_critical_method (MonoMethod *method)
2279 return mono_runtime_is_critical_method (method) || sgen_is_critical_method (method);
2283 thread_in_critical_region (SgenThreadInfo *info)
2285 return info->client_info.in_critical_region;
2289 sgen_thread_attach (SgenThreadInfo *info)
2291 if (mono_gc_get_gc_callbacks ()->thread_attach_func && !info->client_info.runtime_data)
2292 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2296 sgen_thread_detach (SgenThreadInfo *p)
2298 /* If a delegate is passed to native code and invoked on a thread we dont
2299 * know about, marshal will register it with mono_threads_attach_coop, but
2300 * we have no way of knowing when that thread goes away. SGen has a TSD
2301 * so we assume that if the domain is still registered, we can detach
2304 if (mono_domain_get ())
2305 mono_thread_detach_internal (mono_thread_internal_current ());
2309 mono_gc_register_thread (void *baseptr)
2311 return mono_thread_info_attach (baseptr) != NULL;
2315 mono_gc_is_gc_thread (void)
2319 result = mono_thread_info_current () != NULL;
2325 sgen_client_thread_register_worker (void)
2327 mono_thread_info_register_small_id ();
2328 mono_native_thread_set_name (mono_native_thread_id_get (), "SGen worker");
2331 /* Variables holding start/end nursery so it won't have to be passed at every call */
2332 static void *scan_area_arg_start, *scan_area_arg_end;
2335 mono_gc_conservatively_scan_area (void *start, void *end)
2337 sgen_conservatively_pin_objects_from ((void **)start, (void **)end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
2341 mono_gc_scan_object (void *obj, void *gc_data)
2343 ScanCopyContext *ctx = (ScanCopyContext *)gc_data;
2344 ctx->ops->copy_or_mark_object ((GCObject**)&obj, ctx->queue);
2349 * Mark from thread stacks and registers.
2352 sgen_client_scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, ScanCopyContext ctx)
2354 scan_area_arg_start = start_nursery;
2355 scan_area_arg_end = end_nursery;
2357 FOREACH_THREAD (info) {
2358 int skip_reason = 0;
2359 void *aligned_stack_start;
2361 if (info->client_info.skip) {
2362 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);
2364 } else if (info->client_info.gc_disabled) {
2365 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);
2367 } else if (!mono_thread_info_is_live (info)) {
2368 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);
2370 } else if (!info->client_info.stack_start) {
2371 SGEN_LOG (3, "Skipping starting or detaching thread %p", info);
2375 binary_protocol_scan_stack ((gpointer)mono_thread_info_get_tid (info), info->client_info.stack_start, info->client_info.stack_end, skip_reason);
2380 g_assert (info->client_info.stack_start);
2381 g_assert (info->client_info.stack_end);
2383 aligned_stack_start = (void*)(mword) ALIGN_TO ((mword)info->client_info.stack_start, SIZEOF_VOID_P);
2385 /* Windows uses a guard page before the committed stack memory pages to detect when the
2386 stack needs to be grown. If we suspend a thread just after a function prolog has
2387 decremented the stack pointer to point into the guard page but before the thread has
2388 been able to read or write to that page, starting the stack scan at aligned_stack_start
2389 will raise a STATUS_GUARD_PAGE_VIOLATION and the process will crash. This code uses
2390 VirtualQuery() to determine whether stack_start points into the guard page and then
2391 updates aligned_stack_start to point at the next non-guard page. */
2392 MEMORY_BASIC_INFORMATION mem_info;
2393 SIZE_T result = VirtualQuery(info->client_info.stack_start, &mem_info, sizeof(mem_info));
2394 g_assert (result != 0);
2395 if (mem_info.Protect & PAGE_GUARD) {
2396 aligned_stack_start = ((char*) mem_info.BaseAddress) + mem_info.RegionSize;
2400 g_assert (info->client_info.suspend_done);
2401 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 ());
2402 if (mono_gc_get_gc_callbacks ()->thread_mark_func && !conservative_stack_mark) {
2403 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);
2404 } else if (!precise) {
2405 if (!conservative_stack_mark) {
2406 fprintf (stderr, "Precise stack mark not supported - disabling.\n");
2407 conservative_stack_mark = TRUE;
2409 //FIXME we should eventually use the new stack_mark from coop
2410 sgen_conservatively_pin_objects_from ((void **)aligned_stack_start, (void **)info->client_info.stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
2414 sgen_conservatively_pin_objects_from ((void**)&info->client_info.ctx, (void**)(&info->client_info.ctx + 1),
2415 start_nursery, end_nursery, PIN_TYPE_STACK);
2418 // This is used on Coop GC for platforms where we cannot get the data for individual registers.
2419 // We force a spill of all registers into the stack and pass a chunk of data into sgen.
2420 //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
2421 MonoThreadUnwindState *state = &info->client_info.info.thread_saved_state [SELF_SUSPEND_STATE_INDEX];
2422 if (state && state->gc_stackdata) {
2423 sgen_conservatively_pin_objects_from ((void **)state->gc_stackdata, (void**)((char*)state->gc_stackdata + state->gc_stackdata_size),
2424 start_nursery, end_nursery, PIN_TYPE_STACK);
2428 if (precise && info->client_info.info.handle_stack) {
2429 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, (GcScanFunc)ctx.ops->copy_or_mark_object, ctx.queue);
2431 } FOREACH_THREAD_END
2435 * mono_gc_set_stack_end:
2437 * Set the end of the current threads stack to STACK_END. The stack space between
2438 * STACK_END and the real end of the threads stack will not be scanned during collections.
2441 mono_gc_set_stack_end (void *stack_end)
2443 SgenThreadInfo *info;
2446 info = mono_thread_info_current ();
2448 SGEN_ASSERT (0, stack_end < info->client_info.stack_end, "Can only lower stack end");
2449 info->client_info.stack_end = stack_end;
2459 mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2461 return sgen_register_root (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED, source, msg);
2465 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2467 return sgen_register_root (start, size, descr, ROOT_TYPE_WBARRIER, source, msg);
2471 mono_gc_deregister_root (char* addr)
2473 sgen_deregister_root (addr);
2482 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
2484 return pthread_create (new_thread, attr, start_routine, arg);
2493 sgen_client_total_allocated_heap_changed (size_t allocated_heap)
2495 mono_runtime_resource_check_limit (MONO_RESOURCE_GC_HEAP, allocated_heap);
2499 mono_gc_user_markers_supported (void)
2505 mono_object_is_alive (MonoObject* o)
2511 mono_gc_get_generation (MonoObject *obj)
2513 if (sgen_ptr_in_nursery (obj))
2519 mono_gc_enable_events (void)
2524 mono_gc_get_gc_name (void)
2530 mono_gc_get_description (void)
2532 #ifdef HAVE_CONC_GC_AS_DEFAULT
2533 return g_strdup ("sgen (concurrent by default)");
2535 return g_strdup ("sgen");
2540 mono_gc_set_desktop_mode (void)
2545 mono_gc_is_moving (void)
2551 mono_gc_is_disabled (void)
2557 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
2564 mono_gc_max_generation (void)
2570 mono_gc_precise_stack_mark_enabled (void)
2572 return !conservative_stack_mark;
2576 mono_gc_collect (int generation)
2578 sgen_gc_collect (generation);
2582 mono_gc_collection_count (int generation)
2584 return sgen_gc_collection_count (generation);
2588 mono_gc_get_used_size (void)
2590 return (int64_t)sgen_gc_get_used_size ();
2594 mono_gc_get_heap_size (void)
2596 return (int64_t)sgen_gc_get_total_heap_allocation ();
2600 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
2602 return sgen_make_user_root_descriptor (marker);
2606 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
2608 return SGEN_DESC_STRING;
2612 mono_gc_get_nursery (int *shift_bits, size_t *size)
2614 *size = sgen_nursery_size;
2615 *shift_bits = DEFAULT_NURSERY_BITS;
2616 return sgen_get_nursery_start ();
2620 mono_gc_get_los_limit (void)
2622 return SGEN_MAX_SMALL_OBJ_SIZE;
2626 sgen_client_default_metadata (void)
2628 return mono_domain_get ();
2632 sgen_client_metadata_for_object (GCObject *obj)
2634 return mono_object_domain (obj);
2638 * mono_gchandle_is_in_domain:
2639 * @gchandle: a GCHandle's handle.
2640 * @domain: An application domain.
2642 * Returns: TRUE if the object wrapped by the @gchandle belongs to the specific @domain.
2645 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
2647 MonoDomain *gchandle_domain = (MonoDomain *)sgen_gchandle_get_metadata (gchandle);
2648 return domain->domain_id == gchandle_domain->domain_id;
2652 * mono_gchandle_free_domain:
2653 * @unloading: domain that is unloading
2655 * Function used internally to cleanup any GC handle for objects belonging
2656 * to the specified domain during appdomain unload.
2659 mono_gchandle_free_domain (MonoDomain *unloading)
2664 null_link_if_in_domain (gpointer hidden, GCHandleType handle_type, int max_generation, gpointer user)
2666 MonoDomain *unloading_domain = (MonoDomain *)user;
2667 MonoDomain *obj_domain;
2668 gboolean is_weak = MONO_GC_HANDLE_TYPE_IS_WEAK (handle_type);
2669 if (MONO_GC_HANDLE_IS_OBJECT_POINTER (hidden)) {
2670 MonoObject *obj = (MonoObject *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2671 obj_domain = mono_object_domain (obj);
2673 obj_domain = (MonoDomain *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2675 if (unloading_domain->domain_id == obj_domain->domain_id)
2681 sgen_null_links_for_domain (MonoDomain *domain)
2684 for (type = HANDLE_TYPE_MIN; type < HANDLE_TYPE_MAX; ++type)
2685 sgen_gchandle_iterate ((GCHandleType)type, GENERATION_OLD, null_link_if_in_domain, domain);
2689 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
2691 sgen_gchandle_set_target (gchandle, obj);
2695 sgen_client_gchandle_created (int handle_type, GCObject *obj, guint32 handle)
2697 #ifndef DISABLE_PERFCOUNTERS
2698 mono_perfcounters->gc_num_handles++;
2700 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handle_type, handle, obj);
2704 sgen_client_gchandle_destroyed (int handle_type, guint32 handle)
2706 #ifndef DISABLE_PERFCOUNTERS
2707 mono_perfcounters->gc_num_handles--;
2709 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handle_type, handle, NULL);
2713 sgen_client_ensure_weak_gchandles_accessible (void)
2716 * During the second bridge processing step the world is
2717 * running again. That step processes all weak links once
2718 * more to null those that refer to dead objects. Before that
2719 * is completed, those links must not be followed, so we
2720 * conservatively wait for bridge processing when any weak
2721 * link is dereferenced.
2723 /* FIXME: A GC can occur after this check fails, in which case we
2724 * should wait for bridge processing but would fail to do so.
2726 if (G_UNLIKELY (bridge_processing_in_progress))
2727 mono_gc_wait_for_bridge_processing ();
2731 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
2735 result = func (data);
2736 UNLOCK_INTERRUPTION;
2741 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
2747 mono_gc_get_card_table (int *shift_bits, gpointer *mask)
2749 return sgen_get_card_table_configuration (shift_bits, mask);
2753 mono_gc_card_table_nursery_check (void)
2755 return !sgen_get_major_collector ()->is_concurrent;
2758 /* Negative value to remove */
2760 mono_gc_add_memory_pressure (gint64 value)
2762 /* FIXME: Implement at some point? */
2770 sgen_client_degraded_allocation (size_t size)
2772 static int last_major_gc_warned = -1;
2773 static int num_degraded = 0;
2775 if (last_major_gc_warned < (int)gc_stats.major_gc_count) {
2777 if (num_degraded == 1 || num_degraded == 3)
2778 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Degraded allocation. Consider increasing nursery-size if the warning persists.");
2779 else if (num_degraded == 10)
2780 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Repeated degraded allocation. Consider increasing nursery-size.");
2781 last_major_gc_warned = gc_stats.major_gc_count;
2790 sgen_client_description_for_internal_mem_type (int type)
2793 case INTERNAL_MEM_EPHEMERON_LINK: return "ephemeron-link";
2800 sgen_client_pre_collection_checks (void)
2802 if (sgen_mono_xdomain_checks) {
2803 sgen_clear_nursery_fragments ();
2804 sgen_check_for_xdomain_refs ();
2809 sgen_client_vtable_is_inited (MonoVTable *vt)
2811 return vt->klass->inited;
2815 sgen_client_vtable_get_namespace (MonoVTable *vt)
2817 return vt->klass->name_space;
2821 sgen_client_vtable_get_name (MonoVTable *vt)
2823 return vt->klass->name;
2831 sgen_client_init (void)
2834 MonoThreadInfoCallbacks cb;
2836 cb.thread_register = sgen_thread_register;
2837 cb.thread_detach = sgen_thread_detach;
2838 cb.thread_unregister = sgen_thread_unregister;
2839 cb.thread_attach = sgen_thread_attach;
2840 cb.mono_method_is_critical = (gboolean (*)(void *))is_critical_method;
2841 cb.mono_thread_in_critical_region = thread_in_critical_region;
2843 mono_threads_init (&cb, sizeof (SgenThreadInfo));
2845 ///* Keep this the default for now */
2846 /* Precise marking is broken on all supported targets. Disable until fixed. */
2847 conservative_stack_mark = TRUE;
2849 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
2851 mono_sgen_init_stw ();
2853 #ifndef HAVE_KW_THREAD
2854 mono_native_tls_alloc (&thread_info_key, NULL);
2855 #if defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
2857 * CEE_MONO_TLS requires the tls offset, not the key, so the code below only works on darwin,
2858 * where the two are the same.
2860 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, thread_info_key);
2864 int tls_offset = -1;
2865 MONO_THREAD_VAR_OFFSET (sgen_thread_info, tls_offset);
2866 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, tls_offset);
2871 * This needs to happen before any internal allocations because
2872 * it inits the small id which is required for hazard pointer
2877 mono_gc_register_thread (&dummy);
2881 sgen_client_handle_gc_param (const char *opt)
2883 if (g_str_has_prefix (opt, "stack-mark=")) {
2884 opt = strchr (opt, '=') + 1;
2885 if (!strcmp (opt, "precise")) {
2886 conservative_stack_mark = FALSE;
2887 } else if (!strcmp (opt, "conservative")) {
2888 conservative_stack_mark = TRUE;
2890 sgen_env_var_error (MONO_GC_PARAMS_NAME, conservative_stack_mark ? "Using `conservative`." : "Using `precise`.",
2891 "Invalid value `%s` for `stack-mark` option, possible values are: `precise`, `conservative`.", opt);
2893 } else if (g_str_has_prefix (opt, "bridge-implementation=")) {
2894 opt = strchr (opt, '=') + 1;
2895 sgen_set_bridge_implementation (opt);
2896 } else if (g_str_has_prefix (opt, "toggleref-test")) {
2897 /* FIXME: This should probably in MONO_GC_DEBUG */
2898 sgen_register_test_toggleref_callback ();
2906 sgen_client_print_gc_params_usage (void)
2908 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
2912 sgen_client_handle_gc_debug (const char *opt)
2914 if (!strcmp (opt, "xdomain-checks")) {
2915 sgen_mono_xdomain_checks = TRUE;
2916 } else if (!strcmp (opt, "do-not-finalize")) {
2917 mono_do_not_finalize = TRUE;
2918 } else if (g_str_has_prefix (opt, "do-not-finalize=")) {
2919 opt = strchr (opt, '=') + 1;
2920 mono_do_not_finalize = TRUE;
2921 mono_do_not_finalize_class_names = g_strsplit (opt, ",", 0);
2922 } else if (!strcmp (opt, "log-finalizers")) {
2923 log_finalizers = TRUE;
2924 } else if (!strcmp (opt, "no-managed-allocator")) {
2925 sgen_set_use_managed_allocator (FALSE);
2926 } else if (!sgen_bridge_handle_gc_debug (opt)) {
2933 sgen_client_print_gc_debug_usage (void)
2935 fprintf (stderr, " xdomain-checks\n");
2936 fprintf (stderr, " do-not-finalize\n");
2937 fprintf (stderr, " log-finalizers\n");
2938 fprintf (stderr, " no-managed-allocator\n");
2939 sgen_bridge_print_gc_debug_usage ();
2944 sgen_client_get_provenance (void)
2946 #ifdef SGEN_OBJECT_PROVENANCE
2947 MonoGCCallbacks *cb = mono_gc_get_gc_callbacks ();
2948 gpointer (*get_provenance_func) (void);
2951 get_provenance_func = cb->get_provenance_func;
2952 if (get_provenance_func)
2953 return get_provenance_func ();
2961 sgen_client_describe_invalid_pointer (GCObject *ptr)
2963 sgen_bridge_describe_pointer (ptr);
2966 static gboolean gc_inited;
2969 mono_gc_base_init (void)
2974 mono_counters_init ();
2976 #ifdef HEAVY_STATISTICS
2977 mono_counters_register ("los marked cards", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_marked_cards);
2978 mono_counters_register ("los array cards scanned ", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_cards);
2979 mono_counters_register ("los array remsets", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_remsets);
2981 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_set_arrayref);
2982 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_value_copy);
2983 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_object_copy);
2988 if (nursery_canaries_enabled ())
2989 sgen_set_use_managed_allocator (FALSE);
2991 #if defined(HAVE_KW_THREAD)
2992 /* This can happen with using libmonosgen.so */
2993 if (mono_tls_key_get_offset (TLS_KEY_SGEN_THREAD_INFO) == -1)
2994 sgen_set_use_managed_allocator (FALSE);
3001 mono_gc_base_cleanup (void)
3003 sgen_thread_pool_shutdown ();
3007 mono_gc_is_null (void)