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 if (sgen_ptr_in_nursery (obj) || ptr_on_stack (obj) || !SGEN_OBJECT_HAS_REFERENCES (src)) {
144 size = mono_object_class (obj)->instance_size;
145 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
146 size - sizeof (MonoObject));
150 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
151 if (binary_protocol_is_heavy_enabled ())
152 scan_object_for_binary_protocol_copy_wbarrier (obj, (char*)src, (mword) src->vtable->gc_descr);
155 sgen_get_remset ()->wbarrier_object_copy (obj, src);
159 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
161 HEAVY_STAT (++stat_wbarrier_set_arrayref);
162 if (sgen_ptr_in_nursery (slot_ptr)) {
163 *(void**)slot_ptr = value;
166 SGEN_LOG (8, "Adding remset at %p", slot_ptr);
168 binary_protocol_wbarrier (slot_ptr, value, value->vtable);
170 sgen_get_remset ()->wbarrier_set_field ((GCObject*)arr, slot_ptr, value);
174 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
176 mono_gc_wbarrier_set_arrayref ((MonoArray*)obj, field_ptr, value);
180 mono_gc_wbarrier_value_copy_bitmap (gpointer _dest, gpointer _src, int size, unsigned bitmap)
182 sgen_wbarrier_value_copy_bitmap (_dest, _src, size, bitmap);
185 static MonoMethod *write_barrier_conc_method;
186 static MonoMethod *write_barrier_noconc_method;
189 sgen_is_critical_method (MonoMethod *method)
191 return (method == write_barrier_conc_method || method == write_barrier_noconc_method || sgen_is_managed_allocator (method));
195 sgen_has_critical_method (void)
197 return write_barrier_conc_method || write_barrier_noconc_method || sgen_has_managed_allocator ();
203 emit_nursery_check (MonoMethodBuilder *mb, int *nursery_check_return_labels, gboolean is_concurrent)
205 int shifted_nursery_start = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
207 memset (nursery_check_return_labels, 0, sizeof (int) * 2);
208 // if (ptr_in_nursery (ptr)) return;
210 * Masking out the bits might be faster, but we would have to use 64 bit
211 * immediates, which might be slower.
213 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
214 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_START);
215 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
216 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
217 mono_mb_emit_byte (mb, CEE_SHR_UN);
218 mono_mb_emit_stloc (mb, shifted_nursery_start);
220 mono_mb_emit_ldarg (mb, 0);
221 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
222 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
223 mono_mb_emit_byte (mb, CEE_SHR_UN);
224 mono_mb_emit_ldloc (mb, shifted_nursery_start);
225 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BEQ);
227 if (!is_concurrent) {
228 // if (!ptr_in_nursery (*ptr)) return;
229 mono_mb_emit_ldarg (mb, 0);
230 mono_mb_emit_byte (mb, CEE_LDIND_I);
231 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
232 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
233 mono_mb_emit_byte (mb, CEE_SHR_UN);
234 mono_mb_emit_ldloc (mb, shifted_nursery_start);
235 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BNE_UN);
241 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
244 MonoMethodBuilder *mb;
245 MonoMethodSignature *sig;
246 MonoMethod **write_barrier_method_addr;
248 #ifdef MANAGED_WBARRIER
249 int i, nursery_check_labels [2];
252 // FIXME: Maybe create a separate version for ctors (the branch would be
253 // correctly predicted more times)
255 write_barrier_method_addr = &write_barrier_conc_method;
257 write_barrier_method_addr = &write_barrier_noconc_method;
259 if (*write_barrier_method_addr)
260 return *write_barrier_method_addr;
262 /* Create the IL version of mono_gc_barrier_generic_store () */
263 sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
264 sig->ret = &mono_defaults.void_class->byval_arg;
265 sig->params [0] = &mono_defaults.int_class->byval_arg;
268 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_conc", MONO_WRAPPER_WRITE_BARRIER);
270 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_noconc", MONO_WRAPPER_WRITE_BARRIER);
273 #ifdef MANAGED_WBARRIER
274 emit_nursery_check (mb, nursery_check_labels, is_concurrent);
276 addr = sgen_cardtable + ((address >> CARD_BITS) & CARD_MASK)
280 LDC_PTR sgen_cardtable
286 if (SGEN_HAVE_OVERLAPPING_CARDS) {
287 LDC_PTR card_table_mask
294 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
295 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_CARD_TABLE);
296 mono_mb_emit_ldarg (mb, 0);
297 mono_mb_emit_icon (mb, CARD_BITS);
298 mono_mb_emit_byte (mb, CEE_SHR_UN);
299 mono_mb_emit_byte (mb, CEE_CONV_I);
300 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
301 #if SIZEOF_VOID_P == 8
302 mono_mb_emit_icon8 (mb, CARD_MASK);
304 mono_mb_emit_icon (mb, CARD_MASK);
306 mono_mb_emit_byte (mb, CEE_CONV_I);
307 mono_mb_emit_byte (mb, CEE_AND);
309 mono_mb_emit_byte (mb, CEE_ADD);
310 mono_mb_emit_icon (mb, 1);
311 mono_mb_emit_byte (mb, CEE_STIND_I1);
314 for (i = 0; i < 2; ++i) {
315 if (nursery_check_labels [i])
316 mono_mb_patch_branch (mb, nursery_check_labels [i]);
318 mono_mb_emit_byte (mb, CEE_RET);
320 mono_mb_emit_ldarg (mb, 0);
321 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
322 mono_mb_emit_byte (mb, CEE_RET);
325 res = mono_mb_create_method (mb, sig, 16);
326 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
327 mono_marshal_set_wrapper_info (res, info);
331 if (*write_barrier_method_addr) {
332 /* Already created */
333 mono_free_method (res);
335 /* double-checked locking */
336 mono_memory_barrier ();
337 *write_barrier_method_addr = res;
341 return *write_barrier_method_addr;
345 mono_gc_get_write_barrier (void)
347 return mono_gc_get_specific_write_barrier (major_collector.is_concurrent);
351 * Dummy filler objects
354 /* Vtable of the objects used to fill out nursery fragments before a collection */
355 static GCVTable array_fill_vtable;
358 get_array_fill_vtable (void)
360 if (!array_fill_vtable) {
361 static MonoClass klass;
362 static char _vtable[sizeof(MonoVTable)+8];
363 MonoVTable* vtable = (MonoVTable*) ALIGN_TO((mword)_vtable, 8);
366 MonoDomain *domain = mono_get_root_domain ();
369 klass.element_class = mono_defaults.byte_class;
371 klass.instance_size = MONO_SIZEOF_MONO_ARRAY;
372 klass.sizes.element_size = 1;
373 klass.name = "array_filler_type";
375 vtable->klass = &klass;
377 vtable->gc_descr = mono_gc_make_descr_for_array (TRUE, &bmap, 0, 1);
380 array_fill_vtable = vtable;
382 return array_fill_vtable;
386 sgen_client_array_fill_range (char *start, size_t size)
390 if (size < MONO_SIZEOF_MONO_ARRAY) {
391 memset (start, 0, size);
395 o = (MonoArray*)start;
396 o->obj.vtable = (MonoVTable*)get_array_fill_vtable ();
397 /* Mark this as not a real object */
398 o->obj.synchronisation = (MonoThreadsSync *)GINT_TO_POINTER (-1);
400 o->max_length = (mono_array_size_t)(size - MONO_SIZEOF_MONO_ARRAY);
406 sgen_client_zero_array_fill_header (void *p, size_t size)
408 if (size >= MONO_SIZEOF_MONO_ARRAY) {
409 memset (p, 0, MONO_SIZEOF_MONO_ARRAY);
411 static guint8 zeros [MONO_SIZEOF_MONO_ARRAY];
413 SGEN_ASSERT (0, !memcmp (p, zeros, size), "TLAB segment must be zeroed out.");
421 static MonoGCFinalizerCallbacks fin_callbacks;
424 mono_gc_get_vtable_bits (MonoClass *klass)
427 /* FIXME move this to the bridge code */
428 if (sgen_need_bridge_processing ()) {
429 switch (sgen_bridge_class_kind (klass)) {
430 case GC_BRIDGE_TRANSPARENT_BRIDGE_CLASS:
431 case GC_BRIDGE_OPAQUE_BRIDGE_CLASS:
432 res = SGEN_GC_BIT_BRIDGE_OBJECT;
434 case GC_BRIDGE_OPAQUE_CLASS:
435 res = SGEN_GC_BIT_BRIDGE_OPAQUE_OBJECT;
437 case GC_BRIDGE_TRANSPARENT_CLASS:
441 if (fin_callbacks.is_class_finalization_aware) {
442 if (fin_callbacks.is_class_finalization_aware (klass))
443 res |= SGEN_GC_BIT_FINALIZER_AWARE;
449 is_finalization_aware (MonoObject *obj)
451 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
452 return (vt->gc_bits & SGEN_GC_BIT_FINALIZER_AWARE) == SGEN_GC_BIT_FINALIZER_AWARE;
456 sgen_client_object_queued_for_finalization (GCObject *obj)
458 if (fin_callbacks.object_queued_for_finalization && is_finalization_aware (obj))
459 fin_callbacks.object_queued_for_finalization (obj);
462 if (G_UNLIKELY (MONO_GC_FINALIZE_ENQUEUE_ENABLED ())) {
463 int gen = sgen_ptr_in_nursery (obj) ? GENERATION_NURSERY : GENERATION_OLD;
464 GCVTable vt = SGEN_LOAD_VTABLE (obj);
465 MONO_GC_FINALIZE_ENQUEUE ((mword)obj, sgen_safe_object_get_size (obj),
466 sgen_client_vtable_get_namespace (vt), sgen_client_vtable_get_name (vt), gen,
467 sgen_client_object_has_critical_finalizer (obj));
473 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
475 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
476 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
478 fin_callbacks = *callbacks;
482 sgen_client_run_finalize (MonoObject *obj)
484 mono_gc_run_finalize (obj, NULL);
488 mono_gc_invoke_finalizers (void)
490 return sgen_gc_invoke_finalizers ();
494 mono_gc_pending_finalizers (void)
496 return sgen_have_pending_finalizers ();
500 sgen_client_finalize_notify (void)
502 mono_gc_finalize_notify ();
506 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
508 sgen_object_register_for_finalization (obj, user_data);
512 object_in_domain_predicate (MonoObject *obj, void *user_data)
514 MonoDomain *domain = (MonoDomain *)user_data;
515 if (mono_object_domain (obj) == domain) {
516 SGEN_LOG (5, "Unregistering finalizer for object: %p (%s)", obj, sgen_client_vtable_get_name (SGEN_LOAD_VTABLE (obj)));
523 * mono_gc_finalizers_for_domain:
524 * @domain: the unloading appdomain
525 * @out_array: output array
526 * @out_size: size of output array
528 * Store inside @out_array up to @out_size objects that belong to the unloading
529 * appdomain @domain. Returns the number of stored items. Can be called repeteadly
530 * until it returns 0.
531 * The items are removed from the finalizer data structure, so the caller is supposed
533 * @out_array should be on the stack to allow the GC to know the objects are still alive.
536 mono_gc_finalizers_for_domain (MonoDomain *domain, MonoObject **out_array, int out_size)
538 return sgen_gather_finalizers_if (object_in_domain_predicate, domain, out_array, out_size);
545 typedef struct _EphemeronLinkNode EphemeronLinkNode;
547 struct _EphemeronLinkNode {
548 EphemeronLinkNode *next;
557 static EphemeronLinkNode *ephemeron_list;
559 /* LOCKING: requires that the GC lock is held */
561 null_ephemerons_for_domain (MonoDomain *domain)
563 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
566 MonoObject *object = (MonoObject*)current->array;
569 SGEN_ASSERT (0, object->vtable, "Can't have objects without vtables.");
571 if (object && object->vtable->domain == domain) {
572 EphemeronLinkNode *tmp = current;
575 prev->next = current->next;
577 ephemeron_list = current->next;
579 current = current->next;
580 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
583 current = current->next;
588 /* LOCKING: requires that the GC lock is held */
590 sgen_client_clear_unreachable_ephemerons (ScanCopyContext ctx)
592 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
593 SgenGrayQueue *queue = ctx.queue;
594 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
595 Ephemeron *cur, *array_end;
599 MonoArray *array = current->array;
601 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
602 EphemeronLinkNode *tmp = current;
604 SGEN_LOG (5, "Dead Ephemeron array at %p", array);
607 prev->next = current->next;
609 ephemeron_list = current->next;
611 current = current->next;
612 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
617 copy_func ((GCObject**)&array, queue);
618 current->array = array;
620 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", array);
622 cur = mono_array_addr (array, Ephemeron, 0);
623 array_end = cur + mono_array_length_fast (array);
624 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
626 for (; cur < array_end; ++cur) {
627 GCObject *key = cur->key;
629 if (!key || key == tombstone)
632 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
633 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
634 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
636 if (!sgen_is_object_alive_for_current_gen (key)) {
637 cur->key = tombstone;
643 current = current->next;
648 LOCKING: requires that the GC lock is held
650 Limitations: We scan all ephemerons on every collection since the current design doesn't allow for a simple nursery/mature split.
653 sgen_client_mark_ephemerons (ScanCopyContext ctx)
655 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
656 SgenGrayQueue *queue = ctx.queue;
657 gboolean nothing_marked = TRUE;
658 EphemeronLinkNode *current = ephemeron_list;
659 Ephemeron *cur, *array_end;
662 for (current = ephemeron_list; current; current = current->next) {
663 MonoArray *array = current->array;
664 SGEN_LOG (5, "Ephemeron array at %p", array);
666 /*It has to be alive*/
667 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
668 SGEN_LOG (5, "\tnot reachable");
672 copy_func ((GCObject**)&array, queue);
674 cur = mono_array_addr (array, Ephemeron, 0);
675 array_end = cur + mono_array_length_fast (array);
676 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
678 for (; cur < array_end; ++cur) {
679 GCObject *key = cur->key;
681 if (!key || key == tombstone)
684 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
685 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
686 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
688 if (sgen_is_object_alive_for_current_gen (key)) {
689 GCObject *value = cur->value;
691 copy_func (&cur->key, queue);
693 if (!sgen_is_object_alive_for_current_gen (value))
694 nothing_marked = FALSE;
695 copy_func (&cur->value, queue);
701 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
702 return nothing_marked;
706 mono_gc_ephemeron_array_add (MonoObject *obj)
708 EphemeronLinkNode *node;
712 node = (EphemeronLinkNode *)sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
717 node->array = (MonoArray*)obj;
718 node->next = ephemeron_list;
719 ephemeron_list = node;
721 SGEN_LOG (5, "Registered ephemeron array %p", obj);
732 mono_gc_set_current_thread_appdomain (MonoDomain *domain)
734 SgenThreadInfo *info = mono_thread_info_current ();
736 /* Could be called from sgen_thread_unregister () with a NULL info */
739 info->client_info.stopped_domain = domain;
744 need_remove_object_for_domain (GCObject *start, MonoDomain *domain)
746 if (mono_object_domain (start) == domain) {
747 SGEN_LOG (4, "Need to cleanup object %p", start);
748 binary_protocol_cleanup (start, (gpointer)SGEN_LOAD_VTABLE (start), sgen_safe_object_get_size ((GCObject*)start));
755 process_object_for_domain_clearing (GCObject *start, MonoDomain *domain)
757 MonoVTable *vt = SGEN_LOAD_VTABLE (start);
758 if (vt->klass == mono_defaults.internal_thread_class)
759 g_assert (mono_object_domain (start) == mono_get_root_domain ());
760 /* The object could be a proxy for an object in the domain
762 #ifndef DISABLE_REMOTING
763 if (mono_defaults.real_proxy_class->supertypes && mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
764 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
766 /* The server could already have been zeroed out, so
767 we need to check for that, too. */
768 if (server && (!SGEN_LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
769 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
770 ((MonoRealProxy*)start)->unwrapped_server = NULL;
777 clear_domain_process_object (GCObject *obj, MonoDomain *domain)
781 process_object_for_domain_clearing (obj, domain);
782 remove = need_remove_object_for_domain (obj, domain);
784 if (remove && obj->synchronisation) {
785 guint32 dislink = mono_monitor_get_object_monitor_gchandle (obj);
787 mono_gchandle_free (dislink);
794 clear_domain_process_minor_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
796 if (clear_domain_process_object (obj, domain)) {
797 CANARIFY_SIZE (size);
798 memset (obj, 0, size);
803 clear_domain_process_major_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
805 clear_domain_process_object (obj, domain);
809 clear_domain_free_major_non_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
811 if (need_remove_object_for_domain (obj, domain))
812 major_collector.free_non_pinned_object (obj, size);
816 clear_domain_free_major_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
818 if (need_remove_object_for_domain (obj, domain))
819 major_collector.free_pinned_object (obj, size);
823 * When appdomains are unloaded we can easily remove objects that have finalizers,
824 * but all the others could still be present in random places on the heap.
825 * We need a sweep to get rid of them even though it's going to be costly
827 * The reason we need to remove them is because we access the vtable and class
828 * structures to know the object size and the reference bitmap: once the domain is
829 * unloaded the point to random memory.
832 mono_gc_clear_domain (MonoDomain * domain)
834 LOSObject *bigobj, *prev;
839 binary_protocol_domain_unload_begin (domain);
843 if (sgen_concurrent_collection_in_progress ())
844 sgen_perform_collection (0, GENERATION_OLD, "clear domain", TRUE, FALSE);
845 SGEN_ASSERT (0, !sgen_concurrent_collection_in_progress (), "We just ordered a synchronous collection. Why are we collecting concurrently?");
847 major_collector.finish_sweeping ();
849 sgen_process_fin_stage_entries ();
851 sgen_clear_nursery_fragments ();
853 if (sgen_mono_xdomain_checks && domain != mono_get_root_domain ()) {
854 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
855 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
856 sgen_check_for_xdomain_refs ();
859 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
860 to memory returned to the OS.*/
861 null_ephemerons_for_domain (domain);
862 sgen_null_links_for_domain (domain);
864 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
865 sgen_remove_finalizers_if (object_in_domain_predicate, domain, i);
867 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
868 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE, TRUE);
870 /* We need two passes over major and large objects because
871 freeing such objects might give their memory back to the OS
872 (in the case of large objects) or obliterate its vtable
873 (pinned objects with major-copying or pinned and non-pinned
874 objects with major-mark&sweep), but we might need to
875 dereference a pointer from an object to another object if
876 the first object is a proxy. */
877 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
878 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
879 clear_domain_process_object ((GCObject*)bigobj->data, domain);
882 for (bigobj = los_object_list; bigobj;) {
883 if (need_remove_object_for_domain ((GCObject*)bigobj->data, domain)) {
884 LOSObject *to_free = bigobj;
886 prev->next = bigobj->next;
888 los_object_list = bigobj->next;
889 bigobj = bigobj->next;
890 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
891 sgen_los_free_object (to_free);
895 bigobj = bigobj->next;
897 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
898 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
900 if (domain == mono_get_root_domain ()) {
901 sgen_pin_stats_report ();
902 sgen_object_layout_dump (stdout);
905 sgen_restart_world (0);
907 binary_protocol_domain_unload_end (domain);
908 binary_protocol_flush_buffers (FALSE);
917 static gboolean alloc_events = FALSE;
920 mono_gc_enable_alloc_events (void)
926 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
928 MonoObject *obj = sgen_alloc_obj (vtable, size);
930 if (G_UNLIKELY (alloc_events)) {
932 mono_profiler_allocation (obj);
939 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
941 MonoObject *obj = sgen_alloc_obj_pinned (vtable, size);
943 if (G_UNLIKELY (alloc_events)) {
945 mono_profiler_allocation (obj);
952 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
954 MonoObject *obj = sgen_alloc_obj_mature (vtable, size);
956 if (G_UNLIKELY (alloc_events)) {
958 mono_profiler_allocation (obj);
965 mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
967 /* FIXME: do a single allocation */
968 void *res = calloc (1, size);
971 if (!mono_gc_register_root ((char *)res, size, descr, source, msg)) {
979 mono_gc_free_fixed (void* addr)
981 mono_gc_deregister_root ((char *)addr);
989 static MonoMethod* alloc_method_cache [ATYPE_NUM];
990 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
991 static gboolean use_managed_allocator = TRUE;
993 #ifdef MANAGED_ALLOCATION
995 #ifdef HAVE_KW_THREAD
997 #define EMIT_TLS_ACCESS_VAR(_mb, _var) /* nothing to do */
999 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, _var) \
1001 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1002 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1003 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_IN_CRITICAL_REGION_ADDR); \
1006 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, _var) do { \
1007 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1008 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1009 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_TLAB_NEXT_ADDR); \
1012 #define EMIT_TLS_ACCESS_TEMP_END(mb, _var) do { \
1013 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1014 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1015 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_TLAB_TEMP_END); \
1020 #if defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
1022 // Cache the SgenThreadInfo pointer in a local 'var'.
1023 #define EMIT_TLS_ACCESS_VAR(mb, var) \
1025 var = mono_mb_add_local ((mb), &mono_defaults.int_class->byval_arg); \
1026 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1027 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1028 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_THREAD_INFO); \
1029 mono_mb_emit_stloc ((mb), (var)); \
1032 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, var) \
1034 mono_mb_emit_ldloc ((mb), (var)); \
1035 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenClientThreadInfo, in_critical_region)); \
1036 mono_mb_emit_byte ((mb), CEE_ADD); \
1039 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, var) do { \
1040 mono_mb_emit_ldloc ((mb), (var)); \
1041 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_next_addr)); \
1042 mono_mb_emit_byte ((mb), CEE_ADD); \
1043 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1046 #define EMIT_TLS_ACCESS_TEMP_END(mb, var) do { \
1047 mono_mb_emit_ldloc ((mb), (var)); \
1048 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_temp_end)); \
1049 mono_mb_emit_byte ((mb), CEE_ADD); \
1050 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1054 #define EMIT_TLS_ACCESS_VAR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1055 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1056 #define EMIT_TLS_ACCESS_TEMP_END(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1057 #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)
1062 /* FIXME: Do this in the JIT, where specialized allocation sequences can be created
1063 * for each class. This is currently not easy to do, as it is hard to generate basic
1064 * blocks + branches, but it is easy with the linear IL codebase.
1066 * For this to work we'd need to solve the TLAB race, first. Now we
1067 * require the allocator to be in a few known methods to make sure
1068 * that they are executed atomically via the restart mechanism.
1071 create_allocator (int atype, ManagedAllocatorVariant variant)
1073 int p_var, size_var, thread_var G_GNUC_UNUSED;
1074 gboolean slowpath = variant == MANAGED_ALLOCATOR_SLOW_PATH;
1075 guint32 slowpath_branch, max_size_branch;
1076 MonoMethodBuilder *mb;
1078 MonoMethodSignature *csig;
1079 static gboolean registered = FALSE;
1080 int tlab_next_addr_var, new_next_var;
1081 const char *name = NULL;
1086 mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
1087 mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
1088 mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE);
1092 if (atype == ATYPE_SMALL) {
1093 name = slowpath ? "SlowAllocSmall" : "AllocSmall";
1094 } else if (atype == ATYPE_NORMAL) {
1095 name = slowpath ? "SlowAlloc" : "Alloc";
1096 } else if (atype == ATYPE_VECTOR) {
1097 name = slowpath ? "SlowAllocVector" : "AllocVector";
1098 } else if (atype == ATYPE_STRING) {
1099 name = slowpath ? "SlowAllocString" : "AllocString";
1101 g_assert_not_reached ();
1104 if (atype == ATYPE_NORMAL)
1109 csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
1110 if (atype == ATYPE_STRING) {
1111 csig->ret = &mono_defaults.string_class->byval_arg;
1112 csig->params [0] = &mono_defaults.int_class->byval_arg;
1113 csig->params [1] = &mono_defaults.int32_class->byval_arg;
1115 csig->ret = &mono_defaults.object_class->byval_arg;
1116 for (i = 0; i < num_params; i++)
1117 csig->params [i] = &mono_defaults.int_class->byval_arg;
1120 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
1127 mono_mb_emit_ldarg (mb, 0);
1128 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1131 mono_mb_emit_ldarg (mb, 0);
1132 mono_mb_emit_ldarg (mb, 1);
1133 mono_mb_emit_icall (mb, ves_icall_array_new_specific);
1136 mono_mb_emit_ldarg (mb, 1);
1137 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1140 g_assert_not_reached ();
1146 EMIT_TLS_ACCESS_VAR (mb, thread_var);
1148 size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1149 if (atype == ATYPE_SMALL) {
1150 /* size_var = size_arg */
1151 mono_mb_emit_ldarg (mb, 1);
1152 mono_mb_emit_stloc (mb, size_var);
1153 } else if (atype == ATYPE_NORMAL) {
1154 /* size = vtable->klass->instance_size; */
1155 mono_mb_emit_ldarg (mb, 0);
1156 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1157 mono_mb_emit_byte (mb, CEE_ADD);
1158 mono_mb_emit_byte (mb, CEE_LDIND_I);
1159 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, instance_size));
1160 mono_mb_emit_byte (mb, CEE_ADD);
1161 /* FIXME: assert instance_size stays a 4 byte integer */
1162 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1163 mono_mb_emit_byte (mb, CEE_CONV_I);
1164 mono_mb_emit_stloc (mb, size_var);
1165 } else if (atype == ATYPE_VECTOR) {
1166 MonoExceptionClause *clause;
1167 int pos, pos_leave, pos_error;
1168 MonoClass *oom_exc_class;
1172 * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException
1173 * n < 0 => OverflowException
1175 * We can do an unsigned comparison to catch both cases, then in the error
1176 * case compare signed to distinguish between them.
1178 mono_mb_emit_ldarg (mb, 1);
1179 mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
1180 mono_mb_emit_byte (mb, CEE_CONV_U);
1181 pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
1183 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1184 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1185 mono_mb_emit_ldarg (mb, 1);
1186 mono_mb_emit_icon (mb, 0);
1187 pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S);
1188 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1189 mono_mb_patch_short_branch (mb, pos_error);
1190 mono_mb_emit_exception (mb, "OverflowException", NULL);
1192 mono_mb_patch_short_branch (mb, pos);
1194 clause = (MonoExceptionClause *)mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
1195 clause->try_offset = mono_mb_get_label (mb);
1197 /* vtable->klass->sizes.element_size */
1198 mono_mb_emit_ldarg (mb, 0);
1199 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1200 mono_mb_emit_byte (mb, CEE_ADD);
1201 mono_mb_emit_byte (mb, CEE_LDIND_I);
1202 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, sizes));
1203 mono_mb_emit_byte (mb, CEE_ADD);
1204 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1205 mono_mb_emit_byte (mb, CEE_CONV_I);
1208 mono_mb_emit_ldarg (mb, 1);
1209 mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
1210 /* + sizeof (MonoArray) */
1211 mono_mb_emit_icon (mb, MONO_SIZEOF_MONO_ARRAY);
1212 mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
1213 mono_mb_emit_stloc (mb, size_var);
1215 pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);
1218 clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
1219 clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
1220 clause->data.catch_class = mono_class_load_from_name (mono_defaults.corlib,
1221 "System", "OverflowException");
1222 clause->handler_offset = mono_mb_get_label (mb);
1224 oom_exc_class = mono_class_load_from_name (mono_defaults.corlib,
1225 "System", "OutOfMemoryException");
1226 ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
1229 mono_mb_emit_byte (mb, CEE_POP);
1230 mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
1231 mono_mb_emit_byte (mb, CEE_THROW);
1233 clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
1234 mono_mb_set_clauses (mb, 1, clause);
1235 mono_mb_patch_branch (mb, pos_leave);
1237 } else if (atype == ATYPE_STRING) {
1241 * a string allocator method takes the args: (vtable, len)
1243 * bytes = offsetof (MonoString, chars) + ((len + 1) * 2)
1247 * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1251 * offsetof (MonoString, chars) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1252 * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - offsetof (MonoString, chars)) / 2 - 1
1254 mono_mb_emit_ldarg (mb, 1);
1255 mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - MONO_STRUCT_OFFSET (MonoString, chars)) / 2 - 1);
1256 pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
1258 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1259 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1260 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1261 mono_mb_patch_short_branch (mb, pos);
1263 mono_mb_emit_ldarg (mb, 1);
1264 mono_mb_emit_icon (mb, 1);
1265 mono_mb_emit_byte (mb, MONO_CEE_SHL);
1266 //WE manually fold the above + 2 here
1267 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, chars) + 2);
1268 mono_mb_emit_byte (mb, CEE_ADD);
1269 mono_mb_emit_stloc (mb, size_var);
1271 g_assert_not_reached ();
1274 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1275 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1276 mono_mb_emit_byte (mb, CEE_LDC_I4_1);
1277 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1278 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1279 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1282 /* size += ALLOC_ALIGN - 1; */
1283 mono_mb_emit_ldloc (mb, size_var);
1284 mono_mb_emit_icon (mb, SGEN_ALLOC_ALIGN - 1);
1285 mono_mb_emit_byte (mb, CEE_ADD);
1286 /* size &= ~(ALLOC_ALIGN - 1); */
1287 mono_mb_emit_icon (mb, ~(SGEN_ALLOC_ALIGN - 1));
1288 mono_mb_emit_byte (mb, CEE_AND);
1289 mono_mb_emit_stloc (mb, size_var);
1291 /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
1292 if (atype != ATYPE_SMALL) {
1293 mono_mb_emit_ldloc (mb, size_var);
1294 mono_mb_emit_icon (mb, SGEN_MAX_SMALL_OBJ_SIZE);
1295 max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
1299 * We need to modify tlab_next, but the JIT only supports reading, so we read
1300 * another tls var holding its address instead.
1303 /* tlab_next_addr (local) = tlab_next_addr (TLS var) */
1304 tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1305 EMIT_TLS_ACCESS_NEXT_ADDR (mb, thread_var);
1306 mono_mb_emit_stloc (mb, tlab_next_addr_var);
1308 /* p = (void**)tlab_next; */
1309 p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1310 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1311 mono_mb_emit_byte (mb, CEE_LDIND_I);
1312 mono_mb_emit_stloc (mb, p_var);
1314 /* new_next = (char*)p + size; */
1315 new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1316 mono_mb_emit_ldloc (mb, p_var);
1317 mono_mb_emit_ldloc (mb, size_var);
1318 mono_mb_emit_byte (mb, CEE_CONV_I);
1319 mono_mb_emit_byte (mb, CEE_ADD);
1320 mono_mb_emit_stloc (mb, new_next_var);
1322 /* if (G_LIKELY (new_next < tlab_temp_end)) */
1323 mono_mb_emit_ldloc (mb, new_next_var);
1324 EMIT_TLS_ACCESS_TEMP_END (mb, thread_var);
1325 slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1328 if (atype != ATYPE_SMALL)
1329 mono_mb_patch_short_branch (mb, max_size_branch);
1331 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1332 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1334 * We are no longer in a critical section. We need to do this before calling
1335 * to unmanaged land in order to avoid stw deadlocks since unmanaged code
1338 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1339 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1340 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1341 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1342 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1343 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1346 /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
1347 mono_mb_emit_ldarg (mb, 0);
1348 mono_mb_emit_ldloc (mb, size_var);
1349 if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
1350 mono_mb_emit_icall (mb, mono_gc_alloc_obj);
1351 } else if (atype == ATYPE_VECTOR) {
1352 mono_mb_emit_ldarg (mb, 1);
1353 mono_mb_emit_icall (mb, mono_gc_alloc_vector);
1354 } else if (atype == ATYPE_STRING) {
1355 mono_mb_emit_ldarg (mb, 1);
1356 mono_mb_emit_icall (mb, mono_gc_alloc_string);
1358 g_assert_not_reached ();
1360 mono_mb_emit_byte (mb, CEE_RET);
1363 mono_mb_patch_short_branch (mb, slowpath_branch);
1365 /* FIXME: Memory barrier */
1367 /* tlab_next = new_next */
1368 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1369 mono_mb_emit_ldloc (mb, new_next_var);
1370 mono_mb_emit_byte (mb, CEE_STIND_I);
1373 mono_mb_emit_ldloc (mb, p_var);
1374 mono_mb_emit_ldarg (mb, 0);
1375 mono_mb_emit_byte (mb, CEE_STIND_I);
1377 if (atype == ATYPE_VECTOR) {
1378 /* arr->max_length = max_length; */
1379 mono_mb_emit_ldloc (mb, p_var);
1380 mono_mb_emit_ldflda (mb, MONO_STRUCT_OFFSET (MonoArray, max_length));
1381 mono_mb_emit_ldarg (mb, 1);
1382 #ifdef MONO_BIG_ARRAYS
1383 mono_mb_emit_byte (mb, CEE_STIND_I);
1385 mono_mb_emit_byte (mb, CEE_STIND_I4);
1387 } else if (atype == ATYPE_STRING) {
1388 /* need to set length and clear the last char */
1389 /* s->length = len; */
1390 mono_mb_emit_ldloc (mb, p_var);
1391 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, length));
1392 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1393 mono_mb_emit_ldarg (mb, 1);
1394 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1397 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1398 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1399 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1400 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1401 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1403 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1404 mono_mb_emit_byte (mb, CEE_MONO_MEMORY_BARRIER);
1407 We must make sure both vtable and max_length are globaly visible before returning to managed land.
1409 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_REL);
1412 mono_mb_emit_ldloc (mb, p_var);
1415 mono_mb_emit_byte (mb, CEE_RET);
1418 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1419 info->d.alloc.gc_name = "sgen";
1420 info->d.alloc.alloc_type = atype;
1423 mb->init_locals = FALSE;
1426 res = mono_mb_create (mb, csig, 8, info);
1435 mono_gc_get_aligned_size_for_allocator (int size)
1437 return SGEN_ALIGN_UP (size);
1441 * Generate an allocator method implementing the fast path of mono_gc_alloc_obj ().
1442 * The signature of the called method is:
1443 * object allocate (MonoVTable *vtable)
1446 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1448 #ifdef MANAGED_ALLOCATION
1449 if (collect_before_allocs)
1451 if (!mono_runtime_has_tls_get ())
1453 if (klass->instance_size > tlab_size)
1455 if (known_instance_size && ALIGN_TO (klass->instance_size, SGEN_ALLOC_ALIGN) >= SGEN_MAX_SMALL_OBJ_SIZE)
1457 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1461 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1463 if (klass->byval_arg.type == MONO_TYPE_STRING)
1464 return mono_gc_get_managed_allocator_by_type (ATYPE_STRING, MANAGED_ALLOCATOR_REGULAR);
1465 /* Generic classes have dynamic field and can go above MAX_SMALL_OBJ_SIZE. */
1466 if (known_instance_size)
1467 return mono_gc_get_managed_allocator_by_type (ATYPE_SMALL, MANAGED_ALLOCATOR_REGULAR);
1469 return mono_gc_get_managed_allocator_by_type (ATYPE_NORMAL, MANAGED_ALLOCATOR_REGULAR);
1476 mono_gc_get_managed_array_allocator (MonoClass *klass)
1478 #ifdef MANAGED_ALLOCATION
1479 if (klass->rank != 1)
1481 if (!mono_runtime_has_tls_get ())
1483 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1485 if (has_per_allocation_action)
1487 g_assert (!mono_class_has_finalizer (klass) && !mono_class_is_marshalbyref (klass));
1489 return mono_gc_get_managed_allocator_by_type (ATYPE_VECTOR, MANAGED_ALLOCATOR_REGULAR);
1496 sgen_set_use_managed_allocator (gboolean flag)
1498 use_managed_allocator = flag;
1502 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1504 #ifdef MANAGED_ALLOCATION
1508 if (!use_managed_allocator)
1511 if (!mono_runtime_has_tls_get ())
1515 case MANAGED_ALLOCATOR_REGULAR: cache = alloc_method_cache; break;
1516 case MANAGED_ALLOCATOR_SLOW_PATH: cache = slowpath_alloc_method_cache; break;
1517 default: g_assert_not_reached (); break;
1520 res = cache [atype];
1524 res = create_allocator (atype, variant);
1526 if (cache [atype]) {
1527 mono_free_method (res);
1528 res = cache [atype];
1530 mono_memory_barrier ();
1531 cache [atype] = res;
1542 mono_gc_get_managed_allocator_types (void)
1548 sgen_is_managed_allocator (MonoMethod *method)
1552 for (i = 0; i < ATYPE_NUM; ++i)
1553 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1559 sgen_has_managed_allocator (void)
1563 for (i = 0; i < ATYPE_NUM; ++i)
1564 if (alloc_method_cache [i] || slowpath_alloc_method_cache [i])
1570 * Cardtable scanning
1573 #define MWORD_MASK (sizeof (mword) - 1)
1576 find_card_offset (mword card)
1578 /*XXX Use assembly as this generates some pretty bad code */
1579 #if defined(__i386__) && defined(__GNUC__)
1580 return (__builtin_ffs (card) - 1) / 8;
1581 #elif defined(__x86_64__) && defined(__GNUC__)
1582 return (__builtin_ffsll (card) - 1) / 8;
1583 #elif defined(__s390x__)
1584 return (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1587 guint8 *ptr = (guint8 *) &card;
1588 for (i = 0; i < sizeof (mword); ++i) {
1597 find_next_card (guint8 *card_data, guint8 *end)
1599 mword *cards, *cards_end;
1602 while ((((mword)card_data) & MWORD_MASK) && card_data < end) {
1608 if (card_data == end)
1611 cards = (mword*)card_data;
1612 cards_end = (mword*)((mword)end & ~MWORD_MASK);
1613 while (cards < cards_end) {
1616 return (guint8*)cards + find_card_offset (card);
1620 card_data = (guint8*)cards_end;
1621 while (card_data < end) {
1630 #define ARRAY_OBJ_INDEX(ptr,array,elem_size) (((char*)(ptr) - ((char*)(array) + G_STRUCT_OFFSET (MonoArray, vector))) / (elem_size))
1633 sgen_client_cardtable_scan_object (GCObject *obj, mword block_obj_size, guint8 *cards, ScanCopyContext ctx)
1635 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
1636 MonoClass *klass = vt->klass;
1638 SGEN_ASSERT (0, SGEN_VTABLE_HAS_REFERENCES (vt), "Why would we ever call this on reference-free objects?");
1641 MonoArray *arr = (MonoArray*)obj;
1642 guint8 *card_data, *card_base;
1643 guint8 *card_data_end;
1644 char *obj_start = (char *)sgen_card_table_align_pointer (obj);
1646 mword obj_size = sgen_mono_array_size (vt, arr, &bounds_size, sgen_vtable_get_descriptor (vt));
1647 /* We don't want to scan the bounds entries at the end of multidimensional arrays */
1648 char *obj_end = (char*)obj + obj_size - bounds_size;
1650 size_t extra_idx = 0;
1652 mword desc = (mword)klass->element_class->gc_descr;
1653 int elem_size = mono_array_element_size (klass);
1655 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1656 guint8 *overflow_scan_end = NULL;
1659 #ifdef SGEN_OBJECT_LAYOUT_STATISTICS
1660 if (klass->element_class->valuetype)
1661 sgen_object_layout_scanned_vtype_array ();
1663 sgen_object_layout_scanned_ref_array ();
1669 card_data = sgen_card_table_get_card_scan_address ((mword)obj);
1671 card_base = card_data;
1672 card_count = sgen_card_table_number_of_cards_in_range ((mword)obj, obj_size);
1673 card_data_end = card_data + card_count;
1676 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1677 /*Check for overflow and if so, setup to scan in two steps*/
1678 if (!cards && card_data_end >= SGEN_SHADOW_CARDTABLE_END) {
1679 overflow_scan_end = sgen_shadow_cardtable + (card_data_end - SGEN_SHADOW_CARDTABLE_END);
1680 card_data_end = SGEN_SHADOW_CARDTABLE_END;
1686 card_data = find_next_card (card_data, card_data_end);
1687 for (; card_data < card_data_end; card_data = find_next_card (card_data + 1, card_data_end)) {
1689 size_t idx = (card_data - card_base) + extra_idx;
1690 char *start = (char*)(obj_start + idx * CARD_SIZE_IN_BYTES);
1691 char *card_end = start + CARD_SIZE_IN_BYTES;
1692 char *first_elem, *elem;
1694 HEAVY_STAT (++los_marked_cards);
1697 sgen_card_table_prepare_card_for_scanning (card_data);
1699 card_end = MIN (card_end, obj_end);
1701 if (start <= (char*)arr->vector)
1704 index = ARRAY_OBJ_INDEX (start, obj, elem_size);
1706 elem = first_elem = (char*)mono_array_addr_with_size_fast ((MonoArray*)obj, elem_size, index);
1707 if (klass->element_class->valuetype) {
1708 ScanVTypeFunc scan_vtype_func = ctx.ops->scan_vtype;
1710 for (; elem < card_end; elem += elem_size)
1711 scan_vtype_func (obj, elem, desc, ctx.queue BINARY_PROTOCOL_ARG (elem_size));
1713 ScanPtrFieldFunc scan_ptr_field_func = ctx.ops->scan_ptr_field;
1715 HEAVY_STAT (++los_array_cards);
1716 for (; elem < card_end; elem += SIZEOF_VOID_P)
1717 scan_ptr_field_func (obj, (GCObject**)elem, ctx.queue);
1720 binary_protocol_card_scan (first_elem, elem - first_elem);
1723 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1724 if (overflow_scan_end) {
1725 extra_idx = card_data - card_base;
1726 card_base = card_data = sgen_shadow_cardtable;
1727 card_data_end = overflow_scan_end;
1728 overflow_scan_end = NULL;
1739 * Array and string allocation
1743 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
1748 if (!SGEN_CAN_ALIGN_UP (size))
1751 #ifndef DISABLE_CRITICAL_REGION
1752 ENTER_CRITICAL_REGION;
1753 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1755 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1756 arr->max_length = (mono_array_size_t)max_length;
1757 EXIT_CRITICAL_REGION;
1760 EXIT_CRITICAL_REGION;
1765 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1766 if (G_UNLIKELY (!arr)) {
1771 arr->max_length = (mono_array_size_t)max_length;
1776 if (G_UNLIKELY (alloc_events))
1777 mono_profiler_allocation (&arr->obj);
1779 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Vector has incorrect size.");
1784 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
1787 MonoArrayBounds *bounds;
1790 if (!SGEN_CAN_ALIGN_UP (size))
1793 #ifndef DISABLE_CRITICAL_REGION
1794 ENTER_CRITICAL_REGION;
1795 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1797 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1798 arr->max_length = (mono_array_size_t)max_length;
1800 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1801 arr->bounds = bounds;
1802 EXIT_CRITICAL_REGION;
1805 EXIT_CRITICAL_REGION;
1810 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1811 if (G_UNLIKELY (!arr)) {
1816 arr->max_length = (mono_array_size_t)max_length;
1818 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1819 arr->bounds = bounds;
1824 if (G_UNLIKELY (alloc_events))
1825 mono_profiler_allocation (&arr->obj);
1827 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Array has incorrect size.");
1832 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
1837 if (!SGEN_CAN_ALIGN_UP (size))
1840 #ifndef DISABLE_CRITICAL_REGION
1841 ENTER_CRITICAL_REGION;
1842 str = (MonoString*)sgen_try_alloc_obj_nolock (vtable, size);
1844 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1846 EXIT_CRITICAL_REGION;
1849 EXIT_CRITICAL_REGION;
1854 str = (MonoString*)sgen_alloc_obj_nolock (vtable, size);
1855 if (G_UNLIKELY (!str)) {
1865 if (G_UNLIKELY (alloc_events))
1866 mono_profiler_allocation (&str->object);
1876 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1878 mono_unichar2 *new_end = str->chars + new_length;
1880 /* zero the discarded string. This null-delimits the string and allows
1881 * the space to be reclaimed by SGen. */
1883 if (nursery_canaries_enabled () && sgen_ptr_in_nursery (str)) {
1884 CHECK_CANARY_FOR_OBJECT ((GCObject*)str, TRUE);
1885 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2) + CANARY_SIZE);
1886 memcpy (new_end + 1 , CANARY_STRING, CANARY_SIZE);
1888 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1891 str->length = new_length;
1898 #define GC_ROOT_NUM 32
1900 int count; /* must be the first field */
1901 void *objects [GC_ROOT_NUM];
1902 int root_types [GC_ROOT_NUM];
1903 uintptr_t extra_info [GC_ROOT_NUM];
1907 notify_gc_roots (GCRootReport *report)
1911 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
1916 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
1918 if (report->count == GC_ROOT_NUM)
1919 notify_gc_roots (report);
1920 report->objects [report->count] = object;
1921 report->root_types [report->count] = rtype;
1922 report->extra_info [report->count++] = (uintptr_t)SGEN_LOAD_VTABLE (object)->klass;
1926 sgen_client_nursery_objects_pinned (void **definitely_pinned, int count)
1928 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1929 GCRootReport report;
1932 for (idx = 0; idx < count; ++idx)
1933 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1934 notify_gc_roots (&report);
1939 report_finalizer_roots_from_queue (SgenPointerQueue *queue)
1941 GCRootReport report;
1945 for (i = 0; i < queue->next_slot; ++i) {
1946 void *obj = queue->data [i];
1949 add_profile_gc_root (&report, obj, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1951 notify_gc_roots (&report);
1955 report_finalizer_roots (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
1957 report_finalizer_roots_from_queue (fin_ready_queue);
1958 report_finalizer_roots_from_queue (critical_fin_queue);
1961 static GCRootReport *root_report;
1964 single_arg_report_root (MonoObject **obj, void *gc_data)
1967 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1971 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1973 switch (desc & ROOT_DESC_TYPE_MASK) {
1974 case ROOT_DESC_BITMAP:
1975 desc >>= ROOT_DESC_TYPE_SHIFT;
1977 if ((desc & 1) && *start_root) {
1978 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1984 case ROOT_DESC_COMPLEX: {
1985 gsize *bitmap_data = (gsize *)sgen_get_complex_descriptor_bitmap (desc);
1986 gsize bwords = (*bitmap_data) - 1;
1987 void **start_run = start_root;
1989 while (bwords-- > 0) {
1990 gsize bmap = *bitmap_data++;
1991 void **objptr = start_run;
1993 if ((bmap & 1) && *objptr) {
1994 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
1999 start_run += GC_BITS_PER_WORD;
2003 case ROOT_DESC_USER: {
2004 MonoGCRootMarkFunc marker = (MonoGCRootMarkFunc)sgen_get_user_descriptor_func (desc);
2005 root_report = report;
2006 marker ((MonoObject**)start_root, single_arg_report_root, NULL);
2009 case ROOT_DESC_RUN_LEN:
2010 g_assert_not_reached ();
2012 g_assert_not_reached ();
2017 report_registered_roots_by_type (int root_type)
2019 GCRootReport report;
2023 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], void **, start_root, RootRecord *, root) {
2024 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
2025 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
2026 } SGEN_HASH_TABLE_FOREACH_END;
2027 notify_gc_roots (&report);
2031 report_registered_roots (void)
2033 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
2034 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
2038 sgen_client_collecting_minor (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2040 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2041 report_registered_roots ();
2042 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2043 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2046 static GCRootReport major_root_report;
2047 static gboolean profile_roots;
2050 sgen_client_collecting_major_1 (void)
2052 profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2053 memset (&major_root_report, 0, sizeof (GCRootReport));
2057 sgen_client_pinned_los_object (GCObject *obj)
2060 add_profile_gc_root (&major_root_report, (char*)obj, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2064 sgen_client_collecting_major_2 (void)
2067 notify_gc_roots (&major_root_report);
2069 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2070 report_registered_roots ();
2074 sgen_client_collecting_major_3 (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2076 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2077 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2080 #define MOVED_OBJECTS_NUM 64
2081 static void *moved_objects [MOVED_OBJECTS_NUM];
2082 static int moved_objects_idx = 0;
2085 mono_sgen_register_moved_object (void *obj, void *destination)
2087 g_assert (mono_profiler_events & MONO_PROFILE_GC_MOVES);
2089 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2090 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2091 moved_objects_idx = 0;
2093 moved_objects [moved_objects_idx++] = obj;
2094 moved_objects [moved_objects_idx++] = destination;
2098 mono_sgen_gc_event_moves (void)
2100 if (moved_objects_idx) {
2101 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2102 moved_objects_idx = 0;
2110 #define REFS_SIZE 128
2113 MonoGCReferences callback;
2117 MonoObject *refs [REFS_SIZE];
2118 uintptr_t offsets [REFS_SIZE];
2122 #define HANDLE_PTR(ptr,obj) do { \
2124 if (hwi->count == REFS_SIZE) { \
2125 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
2129 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
2130 hwi->refs [hwi->count++] = *(ptr); \
2135 collect_references (HeapWalkInfo *hwi, GCObject *obj, size_t size)
2137 char *start = (char*)obj;
2138 mword desc = sgen_obj_get_descriptor (obj);
2140 #include "sgen/sgen-scan-object.h"
2144 walk_references (GCObject *start, size_t size, void *data)
2146 HeapWalkInfo *hwi = (HeapWalkInfo *)data;
2149 collect_references (hwi, start, size);
2150 if (hwi->count || !hwi->called)
2151 hwi->callback (start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
2155 * mono_gc_walk_heap:
2156 * @flags: flags for future use
2157 * @callback: a function pointer called for each object in the heap
2158 * @data: a user data pointer that is passed to callback
2160 * This function can be used to iterate over all the live objects in the heap:
2161 * for each object, @callback is invoked, providing info about the object's
2162 * location in memory, its class, its size and the objects it references.
2163 * For each referenced object it's offset from the object address is
2164 * reported in the offsets array.
2165 * The object references may be buffered, so the callback may be invoked
2166 * multiple times for the same object: in all but the first call, the size
2167 * argument will be zero.
2168 * Note that this function can be only called in the #MONO_GC_EVENT_PRE_START_WORLD
2169 * profiler event handler.
2171 * Returns: a non-zero value if the GC doesn't support heap walking
2174 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
2179 hwi.callback = callback;
2182 sgen_clear_nursery_fragments ();
2183 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE, TRUE);
2185 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, walk_references, &hwi);
2186 sgen_los_iterate_objects (walk_references, &hwi);
2196 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
2198 gc_callbacks = *callbacks;
2202 mono_gc_get_gc_callbacks ()
2204 return &gc_callbacks;
2208 sgen_client_thread_register (SgenThreadInfo* info, void *stack_bottom_fallback)
2211 guint8 *staddr = NULL;
2213 #ifndef HAVE_KW_THREAD
2214 g_assert (!mono_native_tls_get_value (thread_info_key));
2215 mono_native_tls_set_value (thread_info_key, info);
2217 sgen_thread_info = info;
2220 info->client_info.skip = 0;
2221 info->client_info.stopped_ip = NULL;
2222 info->client_info.stopped_domain = NULL;
2224 info->client_info.stack_start = NULL;
2226 #ifdef SGEN_POSIX_STW
2227 info->client_info.stop_count = -1;
2228 info->client_info.signal = 0;
2231 /* On win32, stack_start_limit should be 0, since the stack can grow dynamically */
2232 mono_thread_info_get_stack_bounds (&staddr, &stsize);
2235 info->client_info.stack_start_limit = staddr;
2237 info->client_info.stack_end = staddr + stsize;
2239 gsize stack_bottom = (gsize)stack_bottom_fallback;
2240 stack_bottom += 4095;
2241 stack_bottom &= ~4095;
2242 info->client_info.stack_end = (char*)stack_bottom;
2245 memset (&info->client_info.ctx, 0, sizeof (MonoContext));
2247 if (mono_gc_get_gc_callbacks ()->thread_attach_func)
2248 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2250 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
2252 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->client_info.stack_end);
2254 info->client_info.info.handle_stack = mono_handle_stack_alloc ();
2258 sgen_client_thread_unregister (SgenThreadInfo *p)
2260 MonoNativeThreadId tid;
2262 #ifndef HAVE_KW_THREAD
2263 mono_native_tls_set_value (thread_info_key, NULL);
2265 sgen_thread_info = NULL;
2268 tid = mono_thread_info_get_tid (p);
2270 if (p->client_info.info.runtime_thread)
2271 mono_threads_add_joinable_thread ((gpointer)tid);
2273 if (mono_gc_get_gc_callbacks ()->thread_detach_func) {
2274 mono_gc_get_gc_callbacks ()->thread_detach_func (p->client_info.runtime_data);
2275 p->client_info.runtime_data = NULL;
2278 binary_protocol_thread_unregister ((gpointer)tid);
2279 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)tid);
2281 HandleStack *handles = (HandleStack*) p->client_info.info.handle_stack;
2282 p->client_info.info.handle_stack = NULL;
2283 mono_handle_stack_free (handles);
2287 mono_gc_set_skip_thread (gboolean skip)
2289 SgenThreadInfo *info = mono_thread_info_current ();
2292 info->client_info.gc_disabled = skip;
2297 is_critical_method (MonoMethod *method)
2299 return mono_runtime_is_critical_method (method) || sgen_is_critical_method (method);
2303 thread_in_critical_region (SgenThreadInfo *info)
2305 return info->client_info.in_critical_region;
2309 sgen_thread_attach (SgenThreadInfo *info)
2311 if (mono_gc_get_gc_callbacks ()->thread_attach_func && !info->client_info.runtime_data)
2312 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2316 sgen_thread_detach (SgenThreadInfo *p)
2318 /* If a delegate is passed to native code and invoked on a thread we dont
2319 * know about, marshal will register it with mono_threads_attach_coop, but
2320 * we have no way of knowing when that thread goes away. SGen has a TSD
2321 * so we assume that if the domain is still registered, we can detach
2324 if (mono_domain_get ())
2325 mono_thread_detach_internal (mono_thread_internal_current ());
2329 mono_gc_register_thread (void *baseptr)
2331 return mono_thread_info_attach (baseptr) != NULL;
2335 mono_gc_is_gc_thread (void)
2339 result = mono_thread_info_current () != NULL;
2345 sgen_client_thread_register_worker (void)
2347 mono_thread_info_register_small_id ();
2348 mono_native_thread_set_name (mono_native_thread_id_get (), "SGen worker");
2351 /* Variables holding start/end nursery so it won't have to be passed at every call */
2352 static void *scan_area_arg_start, *scan_area_arg_end;
2355 mono_gc_conservatively_scan_area (void *start, void *end)
2357 sgen_conservatively_pin_objects_from ((void **)start, (void **)end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
2361 mono_gc_scan_object (void *obj, void *gc_data)
2363 ScanCopyContext *ctx = (ScanCopyContext *)gc_data;
2364 ctx->ops->copy_or_mark_object ((GCObject**)&obj, ctx->queue);
2369 * Mark from thread stacks and registers.
2372 sgen_client_scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, ScanCopyContext ctx)
2374 scan_area_arg_start = start_nursery;
2375 scan_area_arg_end = end_nursery;
2377 FOREACH_THREAD (info) {
2378 int skip_reason = 0;
2379 void *aligned_stack_start;
2381 if (info->client_info.skip) {
2382 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);
2384 } else if (info->client_info.gc_disabled) {
2385 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);
2387 } else if (!mono_thread_info_is_live (info)) {
2388 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);
2390 } else if (!info->client_info.stack_start) {
2391 SGEN_LOG (3, "Skipping starting or detaching thread %p", info);
2395 binary_protocol_scan_stack ((gpointer)mono_thread_info_get_tid (info), info->client_info.stack_start, info->client_info.stack_end, skip_reason);
2400 g_assert (info->client_info.stack_start);
2401 g_assert (info->client_info.stack_end);
2403 aligned_stack_start = (void*)(mword) ALIGN_TO ((mword)info->client_info.stack_start, SIZEOF_VOID_P);
2405 g_assert (info->client_info.suspend_done);
2406 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 ());
2407 if (mono_gc_get_gc_callbacks ()->thread_mark_func && !conservative_stack_mark) {
2408 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);
2409 } else if (!precise) {
2410 if (!conservative_stack_mark) {
2411 fprintf (stderr, "Precise stack mark not supported - disabling.\n");
2412 conservative_stack_mark = TRUE;
2414 //FIXME we should eventually use the new stack_mark from coop
2415 sgen_conservatively_pin_objects_from ((void **)aligned_stack_start, (void **)info->client_info.stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
2419 sgen_conservatively_pin_objects_from ((void**)&info->client_info.ctx, (void**)(&info->client_info.ctx + 1),
2420 start_nursery, end_nursery, PIN_TYPE_STACK);
2423 // This is used on Coop GC for platforms where we cannot get the data for individual registers.
2424 // We force a spill of all registers into the stack and pass a chunk of data into sgen.
2425 //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
2426 MonoThreadUnwindState *state = &info->client_info.info.thread_saved_state [SELF_SUSPEND_STATE_INDEX];
2427 if (state && state->gc_stackdata) {
2428 sgen_conservatively_pin_objects_from ((void **)state->gc_stackdata, (void**)((char*)state->gc_stackdata + state->gc_stackdata_size),
2429 start_nursery, end_nursery, PIN_TYPE_STACK);
2433 if (precise && info->client_info.info.handle_stack) {
2434 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, (GcScanFunc)ctx.ops->copy_or_mark_object, ctx.queue);
2436 } FOREACH_THREAD_END
2440 * mono_gc_set_stack_end:
2442 * Set the end of the current threads stack to STACK_END. The stack space between
2443 * STACK_END and the real end of the threads stack will not be scanned during collections.
2446 mono_gc_set_stack_end (void *stack_end)
2448 SgenThreadInfo *info;
2451 info = mono_thread_info_current ();
2453 SGEN_ASSERT (0, stack_end < info->client_info.stack_end, "Can only lower stack end");
2454 info->client_info.stack_end = stack_end;
2464 mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2466 return sgen_register_root (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED, source, msg);
2470 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2472 return sgen_register_root (start, size, descr, ROOT_TYPE_WBARRIER, source, msg);
2476 mono_gc_deregister_root (char* addr)
2478 sgen_deregister_root (addr);
2487 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
2489 return pthread_create (new_thread, attr, start_routine, arg);
2498 sgen_client_total_allocated_heap_changed (size_t allocated_heap)
2500 mono_runtime_resource_check_limit (MONO_RESOURCE_GC_HEAP, allocated_heap);
2504 mono_gc_user_markers_supported (void)
2510 mono_object_is_alive (MonoObject* o)
2516 mono_gc_get_generation (MonoObject *obj)
2518 if (sgen_ptr_in_nursery (obj))
2524 mono_gc_enable_events (void)
2529 mono_gc_get_gc_name (void)
2535 mono_gc_get_description (void)
2537 #ifdef HAVE_CONC_GC_AS_DEFAULT
2538 return g_strdup ("sgen (concurrent by default)");
2540 return g_strdup ("sgen");
2545 mono_gc_set_desktop_mode (void)
2550 mono_gc_is_moving (void)
2556 mono_gc_is_disabled (void)
2562 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
2569 mono_gc_max_generation (void)
2575 mono_gc_precise_stack_mark_enabled (void)
2577 return !conservative_stack_mark;
2581 mono_gc_collect (int generation)
2583 sgen_gc_collect (generation);
2587 mono_gc_collection_count (int generation)
2589 return sgen_gc_collection_count (generation);
2593 mono_gc_get_used_size (void)
2595 return (int64_t)sgen_gc_get_used_size ();
2599 mono_gc_get_heap_size (void)
2601 return (int64_t)sgen_gc_get_total_heap_allocation ();
2605 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
2607 return sgen_make_user_root_descriptor (marker);
2611 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
2613 return SGEN_DESC_STRING;
2617 mono_gc_get_nursery (int *shift_bits, size_t *size)
2619 *size = sgen_nursery_size;
2620 *shift_bits = DEFAULT_NURSERY_BITS;
2621 return sgen_get_nursery_start ();
2625 mono_gc_get_los_limit (void)
2627 return SGEN_MAX_SMALL_OBJ_SIZE;
2631 sgen_client_default_metadata (void)
2633 return mono_domain_get ();
2637 sgen_client_metadata_for_object (GCObject *obj)
2639 return mono_object_domain (obj);
2643 * mono_gchandle_is_in_domain:
2644 * @gchandle: a GCHandle's handle.
2645 * @domain: An application domain.
2647 * Returns: TRUE if the object wrapped by the @gchandle belongs to the specific @domain.
2650 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
2652 MonoDomain *gchandle_domain = (MonoDomain *)sgen_gchandle_get_metadata (gchandle);
2653 return domain->domain_id == gchandle_domain->domain_id;
2657 * mono_gchandle_free_domain:
2658 * @unloading: domain that is unloading
2660 * Function used internally to cleanup any GC handle for objects belonging
2661 * to the specified domain during appdomain unload.
2664 mono_gchandle_free_domain (MonoDomain *unloading)
2669 null_link_if_in_domain (gpointer hidden, GCHandleType handle_type, int max_generation, gpointer user)
2671 MonoDomain *unloading_domain = (MonoDomain *)user;
2672 MonoDomain *obj_domain;
2673 gboolean is_weak = MONO_GC_HANDLE_TYPE_IS_WEAK (handle_type);
2674 if (MONO_GC_HANDLE_IS_OBJECT_POINTER (hidden)) {
2675 MonoObject *obj = (MonoObject *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2676 obj_domain = mono_object_domain (obj);
2678 obj_domain = (MonoDomain *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2680 if (unloading_domain->domain_id == obj_domain->domain_id)
2686 sgen_null_links_for_domain (MonoDomain *domain)
2689 for (type = HANDLE_TYPE_MIN; type < HANDLE_TYPE_MAX; ++type)
2690 sgen_gchandle_iterate ((GCHandleType)type, GENERATION_OLD, null_link_if_in_domain, domain);
2694 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
2696 sgen_gchandle_set_target (gchandle, obj);
2700 sgen_client_gchandle_created (int handle_type, GCObject *obj, guint32 handle)
2702 #ifndef DISABLE_PERFCOUNTERS
2703 mono_perfcounters->gc_num_handles++;
2705 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handle_type, handle, obj);
2709 sgen_client_gchandle_destroyed (int handle_type, guint32 handle)
2711 #ifndef DISABLE_PERFCOUNTERS
2712 mono_perfcounters->gc_num_handles--;
2714 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handle_type, handle, NULL);
2718 sgen_client_ensure_weak_gchandles_accessible (void)
2721 * During the second bridge processing step the world is
2722 * running again. That step processes all weak links once
2723 * more to null those that refer to dead objects. Before that
2724 * is completed, those links must not be followed, so we
2725 * conservatively wait for bridge processing when any weak
2726 * link is dereferenced.
2728 /* FIXME: A GC can occur after this check fails, in which case we
2729 * should wait for bridge processing but would fail to do so.
2731 if (G_UNLIKELY (bridge_processing_in_progress))
2732 mono_gc_wait_for_bridge_processing ();
2736 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
2740 result = func (data);
2741 UNLOCK_INTERRUPTION;
2746 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
2752 mono_gc_get_card_table (int *shift_bits, gpointer *mask)
2754 return sgen_get_card_table_configuration (shift_bits, mask);
2758 mono_gc_card_table_nursery_check (void)
2760 return !sgen_get_major_collector ()->is_concurrent;
2763 /* Negative value to remove */
2765 mono_gc_add_memory_pressure (gint64 value)
2767 /* FIXME: Implement at some point? */
2775 sgen_client_degraded_allocation (size_t size)
2777 static int last_major_gc_warned = -1;
2778 static int num_degraded = 0;
2780 if (last_major_gc_warned < (int)gc_stats.major_gc_count) {
2782 if (num_degraded == 1 || num_degraded == 3)
2783 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Degraded allocation. Consider increasing nursery-size if the warning persists.");
2784 else if (num_degraded == 10)
2785 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Repeated degraded allocation. Consider increasing nursery-size.");
2786 last_major_gc_warned = gc_stats.major_gc_count;
2795 sgen_client_description_for_internal_mem_type (int type)
2798 case INTERNAL_MEM_EPHEMERON_LINK: return "ephemeron-link";
2805 sgen_client_pre_collection_checks (void)
2807 if (sgen_mono_xdomain_checks) {
2808 sgen_clear_nursery_fragments ();
2809 sgen_check_for_xdomain_refs ();
2814 sgen_client_vtable_is_inited (MonoVTable *vt)
2816 return vt->klass->inited;
2820 sgen_client_vtable_get_namespace (MonoVTable *vt)
2822 return vt->klass->name_space;
2826 sgen_client_vtable_get_name (MonoVTable *vt)
2828 return vt->klass->name;
2836 sgen_client_init (void)
2839 MonoThreadInfoCallbacks cb;
2841 cb.thread_register = sgen_thread_register;
2842 cb.thread_detach = sgen_thread_detach;
2843 cb.thread_unregister = sgen_thread_unregister;
2844 cb.thread_attach = sgen_thread_attach;
2845 cb.mono_method_is_critical = (gboolean (*)(void *))is_critical_method;
2846 cb.mono_thread_in_critical_region = thread_in_critical_region;
2848 mono_threads_init (&cb, sizeof (SgenThreadInfo));
2850 ///* Keep this the default for now */
2851 /* Precise marking is broken on all supported targets. Disable until fixed. */
2852 conservative_stack_mark = TRUE;
2854 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
2856 mono_sgen_init_stw ();
2858 #ifndef HAVE_KW_THREAD
2859 mono_native_tls_alloc (&thread_info_key, NULL);
2860 #if defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
2862 * CEE_MONO_TLS requires the tls offset, not the key, so the code below only works on darwin,
2863 * where the two are the same.
2865 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, thread_info_key);
2869 int tls_offset = -1;
2870 MONO_THREAD_VAR_OFFSET (sgen_thread_info, tls_offset);
2871 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, tls_offset);
2876 * This needs to happen before any internal allocations because
2877 * it inits the small id which is required for hazard pointer
2882 mono_gc_register_thread (&dummy);
2886 sgen_client_handle_gc_param (const char *opt)
2888 if (g_str_has_prefix (opt, "stack-mark=")) {
2889 opt = strchr (opt, '=') + 1;
2890 if (!strcmp (opt, "precise")) {
2891 conservative_stack_mark = FALSE;
2892 } else if (!strcmp (opt, "conservative")) {
2893 conservative_stack_mark = TRUE;
2895 sgen_env_var_error (MONO_GC_PARAMS_NAME, conservative_stack_mark ? "Using `conservative`." : "Using `precise`.",
2896 "Invalid value `%s` for `stack-mark` option, possible values are: `precise`, `conservative`.", opt);
2898 } else if (g_str_has_prefix (opt, "bridge-implementation=")) {
2899 opt = strchr (opt, '=') + 1;
2900 sgen_set_bridge_implementation (opt);
2901 } else if (g_str_has_prefix (opt, "toggleref-test")) {
2902 /* FIXME: This should probably in MONO_GC_DEBUG */
2903 sgen_register_test_toggleref_callback ();
2911 sgen_client_print_gc_params_usage (void)
2913 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
2917 sgen_client_handle_gc_debug (const char *opt)
2919 if (!strcmp (opt, "xdomain-checks")) {
2920 sgen_mono_xdomain_checks = TRUE;
2921 } else if (!strcmp (opt, "do-not-finalize")) {
2922 mono_do_not_finalize = TRUE;
2923 } else if (g_str_has_prefix (opt, "do-not-finalize=")) {
2924 opt = strchr (opt, '=') + 1;
2925 mono_do_not_finalize = TRUE;
2926 mono_do_not_finalize_class_names = g_strsplit (opt, ",", 0);
2927 } else if (!strcmp (opt, "log-finalizers")) {
2928 log_finalizers = TRUE;
2929 } else if (!strcmp (opt, "no-managed-allocator")) {
2930 sgen_set_use_managed_allocator (FALSE);
2931 } else if (!sgen_bridge_handle_gc_debug (opt)) {
2938 sgen_client_print_gc_debug_usage (void)
2940 fprintf (stderr, " xdomain-checks\n");
2941 fprintf (stderr, " do-not-finalize\n");
2942 fprintf (stderr, " log-finalizers\n");
2943 fprintf (stderr, " no-managed-allocator\n");
2944 sgen_bridge_print_gc_debug_usage ();
2949 sgen_client_get_provenance (void)
2951 #ifdef SGEN_OBJECT_PROVENANCE
2952 MonoGCCallbacks *cb = mono_gc_get_gc_callbacks ();
2953 gpointer (*get_provenance_func) (void);
2956 get_provenance_func = cb->get_provenance_func;
2957 if (get_provenance_func)
2958 return get_provenance_func ();
2966 sgen_client_describe_invalid_pointer (GCObject *ptr)
2968 sgen_bridge_describe_pointer (ptr);
2971 static gboolean gc_inited;
2974 mono_gc_base_init (void)
2979 mono_counters_init ();
2981 #ifdef HEAVY_STATISTICS
2982 mono_counters_register ("los marked cards", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_marked_cards);
2983 mono_counters_register ("los array cards scanned ", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_cards);
2984 mono_counters_register ("los array remsets", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_remsets);
2986 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_set_arrayref);
2987 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_value_copy);
2988 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_object_copy);
2993 if (nursery_canaries_enabled ())
2994 sgen_set_use_managed_allocator (FALSE);
2996 #if defined(HAVE_KW_THREAD)
2997 /* This can happen with using libmonosgen.so */
2998 if (mono_tls_key_get_offset (TLS_KEY_SGEN_TLAB_NEXT_ADDR) == -1)
2999 sgen_set_use_managed_allocator (FALSE);
3006 mono_gc_base_cleanup (void)
3008 sgen_thread_pool_shutdown ();
3012 mono_gc_is_null (void)