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 "sgen/sgen-thread-pool.h"
20 #include "metadata/marshal.h"
21 #include "metadata/method-builder.h"
22 #include "metadata/abi-details.h"
23 #include "metadata/mono-gc.h"
24 #include "metadata/runtime.h"
25 #include "metadata/sgen-bridge-internals.h"
26 #include "metadata/gc-internals.h"
27 #include "metadata/handle.h"
28 #include "utils/mono-memory-model.h"
29 #include "utils/mono-logger-internals.h"
30 #include "utils/mono-threads-coop.h"
31 #include "sgen/sgen-thread-pool.h"
32 #include "utils/mono-threads.h"
33 #include "metadata/w32handle.h"
35 #ifdef HEAVY_STATISTICS
36 static guint64 stat_wbarrier_set_arrayref = 0;
37 static guint64 stat_wbarrier_value_copy = 0;
38 static guint64 stat_wbarrier_object_copy = 0;
40 static guint64 los_marked_cards;
41 static guint64 los_array_cards;
42 static guint64 los_array_remsets;
45 /* If set, mark stacks conservatively, even if precise marking is possible */
46 static gboolean conservative_stack_mark = FALSE;
47 /* If set, check that there are no references to the domain left at domain unload */
48 gboolean sgen_mono_xdomain_checks = FALSE;
50 /* Functions supplied by the runtime to be called by the GC */
51 static MonoGCCallbacks gc_callbacks;
53 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
55 #define OPDEF(a,b,c,d,e,f,g,h,i,j) \
59 #include "mono/cil/opcode.def"
70 ptr_on_stack (void *ptr)
72 gpointer stack_start = &stack_start;
73 SgenThreadInfo *info = mono_thread_info_current ();
75 if (ptr >= stack_start && ptr < (gpointer)info->client_info.stack_end)
80 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
82 #define HANDLE_PTR(ptr,obj) do { \
83 gpointer o = *(gpointer*)(ptr); \
85 gpointer d = ((char*)dest) + ((char*)(ptr) - (char*)(obj)); \
86 binary_protocol_wbarrier (d, o, (gpointer) SGEN_LOAD_VTABLE (o)); \
91 scan_object_for_binary_protocol_copy_wbarrier (gpointer dest, char *start, mword desc)
93 #define SCAN_OBJECT_NOVTABLE
94 #include "sgen/sgen-scan-object.h"
99 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
101 HEAVY_STAT (++stat_wbarrier_value_copy);
102 g_assert (klass->valuetype);
104 SGEN_LOG (8, "Adding value remset at %p, count %d, descr %p for class %s (%p)", dest, count, (gpointer)klass->gc_descr, klass->name, klass);
106 if (sgen_ptr_in_nursery (dest) || ptr_on_stack (dest) || !sgen_gc_descr_has_references ((mword)klass->gc_descr)) {
107 size_t element_size = mono_class_value_size (klass, NULL);
108 size_t size = count * element_size;
109 mono_gc_memmove_atomic (dest, src, size);
113 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
114 if (binary_protocol_is_heavy_enabled ()) {
115 size_t element_size = mono_class_value_size (klass, NULL);
117 for (i = 0; i < count; ++i) {
118 scan_object_for_binary_protocol_copy_wbarrier ((char*)dest + i * element_size,
119 (char*)src + i * element_size - sizeof (MonoObject),
120 (mword) klass->gc_descr);
125 sgen_get_remset ()->wbarrier_value_copy (dest, src, count, mono_class_value_size (klass, NULL));
129 * mono_gc_wbarrier_object_copy:
131 * Write barrier to call when obj is the result of a clone or copy of an object.
134 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
138 HEAVY_STAT (++stat_wbarrier_object_copy);
140 SGEN_ASSERT (6, !ptr_on_stack (obj), "Why is this called for a non-reference type?");
141 if (sgen_ptr_in_nursery (obj) || !SGEN_OBJECT_HAS_REFERENCES (src)) {
142 size = mono_object_class (obj)->instance_size;
143 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
144 size - sizeof (MonoObject));
148 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
149 if (binary_protocol_is_heavy_enabled ())
150 scan_object_for_binary_protocol_copy_wbarrier (obj, (char*)src, (mword) src->vtable->gc_descr);
153 sgen_get_remset ()->wbarrier_object_copy (obj, src);
157 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
159 HEAVY_STAT (++stat_wbarrier_set_arrayref);
160 if (sgen_ptr_in_nursery (slot_ptr)) {
161 *(void**)slot_ptr = value;
164 SGEN_LOG (8, "Adding remset at %p", slot_ptr);
166 binary_protocol_wbarrier (slot_ptr, value, value->vtable);
168 sgen_get_remset ()->wbarrier_set_field ((GCObject*)arr, slot_ptr, value);
172 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
174 mono_gc_wbarrier_set_arrayref ((MonoArray*)obj, field_ptr, value);
178 mono_gc_wbarrier_value_copy_bitmap (gpointer _dest, gpointer _src, int size, unsigned bitmap)
180 sgen_wbarrier_value_copy_bitmap (_dest, _src, size, bitmap);
184 mono_gc_get_suspend_signal (void)
186 return mono_threads_suspend_get_suspend_signal ();
190 mono_gc_get_restart_signal (void)
192 return mono_threads_suspend_get_restart_signal ();
195 static MonoMethod *write_barrier_conc_method;
196 static MonoMethod *write_barrier_noconc_method;
199 sgen_is_critical_method (MonoMethod *method)
201 return sgen_is_managed_allocator (method);
205 sgen_has_critical_method (void)
207 return sgen_has_managed_allocator ();
211 ip_in_critical_region (MonoDomain *domain, gpointer ip)
217 * We pass false for 'try_aot' so this becomes async safe.
218 * It won't find aot methods whose jit info is not yet loaded,
219 * so we preload their jit info in the JIT.
221 ji = mono_jit_info_table_find_internal (domain, ip, FALSE, FALSE);
225 method = mono_jit_info_get_method (ji);
227 return mono_runtime_is_critical_method (method) || sgen_is_critical_method (method);
231 mono_gc_is_critical_method (MonoMethod *method)
233 return sgen_is_critical_method (method);
239 emit_nursery_check (MonoMethodBuilder *mb, int *nursery_check_return_labels, gboolean is_concurrent)
241 int shifted_nursery_start = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
243 memset (nursery_check_return_labels, 0, sizeof (int) * 2);
244 // if (ptr_in_nursery (ptr)) return;
246 * Masking out the bits might be faster, but we would have to use 64 bit
247 * immediates, which might be slower.
249 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
250 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_START);
251 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
252 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
253 mono_mb_emit_byte (mb, CEE_SHR_UN);
254 mono_mb_emit_stloc (mb, shifted_nursery_start);
256 mono_mb_emit_ldarg (mb, 0);
257 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
258 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
259 mono_mb_emit_byte (mb, CEE_SHR_UN);
260 mono_mb_emit_ldloc (mb, shifted_nursery_start);
261 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BEQ);
263 if (!is_concurrent) {
264 // if (!ptr_in_nursery (*ptr)) return;
265 mono_mb_emit_ldarg (mb, 0);
266 mono_mb_emit_byte (mb, CEE_LDIND_I);
267 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
268 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
269 mono_mb_emit_byte (mb, CEE_SHR_UN);
270 mono_mb_emit_ldloc (mb, shifted_nursery_start);
271 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BNE_UN);
277 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
280 MonoMethodBuilder *mb;
281 MonoMethodSignature *sig;
282 MonoMethod **write_barrier_method_addr;
284 #ifdef MANAGED_WBARRIER
285 int i, nursery_check_labels [2];
288 // FIXME: Maybe create a separate version for ctors (the branch would be
289 // correctly predicted more times)
291 write_barrier_method_addr = &write_barrier_conc_method;
293 write_barrier_method_addr = &write_barrier_noconc_method;
295 if (*write_barrier_method_addr)
296 return *write_barrier_method_addr;
298 /* Create the IL version of mono_gc_barrier_generic_store () */
299 sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
300 sig->ret = &mono_defaults.void_class->byval_arg;
301 sig->params [0] = &mono_defaults.int_class->byval_arg;
304 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_conc", MONO_WRAPPER_WRITE_BARRIER);
306 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_noconc", MONO_WRAPPER_WRITE_BARRIER);
309 #ifdef MANAGED_WBARRIER
310 emit_nursery_check (mb, nursery_check_labels, is_concurrent);
312 addr = sgen_cardtable + ((address >> CARD_BITS) & CARD_MASK)
316 LDC_PTR sgen_cardtable
322 if (SGEN_HAVE_OVERLAPPING_CARDS) {
323 LDC_PTR card_table_mask
330 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
331 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_CARD_TABLE);
332 mono_mb_emit_ldarg (mb, 0);
333 mono_mb_emit_icon (mb, CARD_BITS);
334 mono_mb_emit_byte (mb, CEE_SHR_UN);
335 mono_mb_emit_byte (mb, CEE_CONV_I);
336 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
337 #if SIZEOF_VOID_P == 8
338 mono_mb_emit_icon8 (mb, CARD_MASK);
340 mono_mb_emit_icon (mb, CARD_MASK);
342 mono_mb_emit_byte (mb, CEE_CONV_I);
343 mono_mb_emit_byte (mb, CEE_AND);
345 mono_mb_emit_byte (mb, CEE_ADD);
346 mono_mb_emit_icon (mb, 1);
347 mono_mb_emit_byte (mb, CEE_STIND_I1);
350 for (i = 0; i < 2; ++i) {
351 if (nursery_check_labels [i])
352 mono_mb_patch_branch (mb, nursery_check_labels [i]);
354 mono_mb_emit_byte (mb, CEE_RET);
356 mono_mb_emit_ldarg (mb, 0);
357 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
358 mono_mb_emit_byte (mb, CEE_RET);
361 res = mono_mb_create_method (mb, sig, 16);
362 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
363 mono_marshal_set_wrapper_info (res, info);
367 if (*write_barrier_method_addr) {
368 /* Already created */
369 mono_free_method (res);
371 /* double-checked locking */
372 mono_memory_barrier ();
373 *write_barrier_method_addr = res;
377 return *write_barrier_method_addr;
381 mono_gc_get_write_barrier (void)
383 return mono_gc_get_specific_write_barrier (major_collector.is_concurrent);
387 * Dummy filler objects
390 /* Vtable of the objects used to fill out nursery fragments before a collection */
391 static GCVTable array_fill_vtable;
394 get_array_fill_vtable (void)
396 if (!array_fill_vtable) {
397 static MonoClass klass;
398 static char _vtable[sizeof(MonoVTable)+8];
399 MonoVTable* vtable = (MonoVTable*) ALIGN_TO((mword)_vtable, 8);
402 MonoDomain *domain = mono_get_root_domain ();
405 klass.element_class = mono_defaults.byte_class;
407 klass.instance_size = MONO_SIZEOF_MONO_ARRAY;
408 klass.sizes.element_size = 1;
409 klass.name = "array_filler_type";
411 vtable->klass = &klass;
413 vtable->gc_descr = mono_gc_make_descr_for_array (TRUE, &bmap, 0, 1);
416 array_fill_vtable = vtable;
418 return array_fill_vtable;
422 sgen_client_array_fill_range (char *start, size_t size)
426 if (size < MONO_SIZEOF_MONO_ARRAY) {
427 memset (start, 0, size);
431 o = (MonoArray*)start;
432 o->obj.vtable = (MonoVTable*)get_array_fill_vtable ();
433 /* Mark this as not a real object */
434 o->obj.synchronisation = (MonoThreadsSync *)GINT_TO_POINTER (-1);
436 o->max_length = (mono_array_size_t)(size - MONO_SIZEOF_MONO_ARRAY);
442 sgen_client_zero_array_fill_header (void *p, size_t size)
444 if (size >= MONO_SIZEOF_MONO_ARRAY) {
445 memset (p, 0, MONO_SIZEOF_MONO_ARRAY);
447 static guint8 zeros [MONO_SIZEOF_MONO_ARRAY];
449 SGEN_ASSERT (0, !memcmp (p, zeros, size), "TLAB segment must be zeroed out.");
457 static MonoGCFinalizerCallbacks fin_callbacks;
460 mono_gc_get_vtable_bits (MonoClass *klass)
463 /* FIXME move this to the bridge code */
464 if (sgen_need_bridge_processing ()) {
465 switch (sgen_bridge_class_kind (klass)) {
466 case GC_BRIDGE_TRANSPARENT_BRIDGE_CLASS:
467 case GC_BRIDGE_OPAQUE_BRIDGE_CLASS:
468 res = SGEN_GC_BIT_BRIDGE_OBJECT;
470 case GC_BRIDGE_OPAQUE_CLASS:
471 res = SGEN_GC_BIT_BRIDGE_OPAQUE_OBJECT;
473 case GC_BRIDGE_TRANSPARENT_CLASS:
477 if (fin_callbacks.is_class_finalization_aware) {
478 if (fin_callbacks.is_class_finalization_aware (klass))
479 res |= SGEN_GC_BIT_FINALIZER_AWARE;
485 is_finalization_aware (MonoObject *obj)
487 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
488 return (vt->gc_bits & SGEN_GC_BIT_FINALIZER_AWARE) == SGEN_GC_BIT_FINALIZER_AWARE;
492 sgen_client_object_queued_for_finalization (GCObject *obj)
494 if (fin_callbacks.object_queued_for_finalization && is_finalization_aware (obj))
495 fin_callbacks.object_queued_for_finalization (obj);
498 if (G_UNLIKELY (MONO_GC_FINALIZE_ENQUEUE_ENABLED ())) {
499 int gen = sgen_ptr_in_nursery (obj) ? GENERATION_NURSERY : GENERATION_OLD;
500 GCVTable vt = SGEN_LOAD_VTABLE (obj);
501 MONO_GC_FINALIZE_ENQUEUE ((mword)obj, sgen_safe_object_get_size (obj),
502 sgen_client_vtable_get_namespace (vt), sgen_client_vtable_get_name (vt), gen,
503 sgen_client_object_has_critical_finalizer (obj));
509 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
511 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
512 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
514 fin_callbacks = *callbacks;
518 sgen_client_run_finalize (MonoObject *obj)
520 mono_gc_run_finalize (obj, NULL);
524 mono_gc_invoke_finalizers (void)
526 return sgen_gc_invoke_finalizers ();
530 mono_gc_pending_finalizers (void)
532 return sgen_have_pending_finalizers ();
536 sgen_client_finalize_notify (void)
538 mono_gc_finalize_notify ();
542 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
544 sgen_object_register_for_finalization (obj, user_data);
548 object_in_domain_predicate (MonoObject *obj, void *user_data)
550 MonoDomain *domain = (MonoDomain *)user_data;
551 if (mono_object_domain (obj) == domain) {
552 SGEN_LOG (5, "Unregistering finalizer for object: %p (%s)", obj, sgen_client_vtable_get_name (SGEN_LOAD_VTABLE (obj)));
559 * mono_gc_finalizers_for_domain:
560 * @domain: the unloading appdomain
561 * @out_array: output array
562 * @out_size: size of output array
564 * Enqueue for finalization all objects that belong to the unloading appdomain @domain
565 * @suspend is used for early termination of the enqueuing process.
568 mono_gc_finalize_domain (MonoDomain *domain)
570 sgen_finalize_if (object_in_domain_predicate, domain);
574 mono_gc_suspend_finalizers (void)
576 sgen_set_suspend_finalizers ();
583 typedef struct _EphemeronLinkNode EphemeronLinkNode;
585 struct _EphemeronLinkNode {
586 EphemeronLinkNode *next;
595 static EphemeronLinkNode *ephemeron_list;
597 /* LOCKING: requires that the GC lock is held */
599 null_ephemerons_for_domain (MonoDomain *domain)
601 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
604 MonoObject *object = (MonoObject*)current->array;
607 SGEN_ASSERT (0, object->vtable, "Can't have objects without vtables.");
609 if (object && object->vtable->domain == domain) {
610 EphemeronLinkNode *tmp = current;
613 prev->next = current->next;
615 ephemeron_list = current->next;
617 current = current->next;
618 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
621 current = current->next;
626 /* LOCKING: requires that the GC lock is held */
628 sgen_client_clear_unreachable_ephemerons (ScanCopyContext ctx)
630 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
631 SgenGrayQueue *queue = ctx.queue;
632 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
633 Ephemeron *cur, *array_end;
637 MonoArray *array = current->array;
639 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
640 EphemeronLinkNode *tmp = current;
642 SGEN_LOG (5, "Dead Ephemeron array at %p", array);
645 prev->next = current->next;
647 ephemeron_list = current->next;
649 current = current->next;
650 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
655 copy_func ((GCObject**)&array, queue);
656 current->array = array;
658 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", array);
660 cur = mono_array_addr (array, Ephemeron, 0);
661 array_end = cur + mono_array_length_fast (array);
662 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
664 for (; cur < array_end; ++cur) {
665 GCObject *key = cur->key;
667 if (!key || key == tombstone)
670 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
671 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
672 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
674 if (!sgen_is_object_alive_for_current_gen (key)) {
675 cur->key = tombstone;
681 current = current->next;
686 LOCKING: requires that the GC lock is held
688 Limitations: We scan all ephemerons on every collection since the current design doesn't allow for a simple nursery/mature split.
691 sgen_client_mark_ephemerons (ScanCopyContext ctx)
693 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
694 SgenGrayQueue *queue = ctx.queue;
695 gboolean nothing_marked = TRUE;
696 EphemeronLinkNode *current = ephemeron_list;
697 Ephemeron *cur, *array_end;
700 for (current = ephemeron_list; current; current = current->next) {
701 MonoArray *array = current->array;
702 SGEN_LOG (5, "Ephemeron array at %p", array);
704 /*It has to be alive*/
705 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
706 SGEN_LOG (5, "\tnot reachable");
710 copy_func ((GCObject**)&array, queue);
712 cur = mono_array_addr (array, Ephemeron, 0);
713 array_end = cur + mono_array_length_fast (array);
714 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
716 for (; cur < array_end; ++cur) {
717 GCObject *key = cur->key;
719 if (!key || key == tombstone)
722 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
723 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
724 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
726 if (sgen_is_object_alive_for_current_gen (key)) {
727 GCObject *value = cur->value;
729 copy_func (&cur->key, queue);
731 if (!sgen_is_object_alive_for_current_gen (value))
732 nothing_marked = FALSE;
733 copy_func (&cur->value, queue);
739 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
740 return nothing_marked;
744 mono_gc_ephemeron_array_add (MonoObject *obj)
746 EphemeronLinkNode *node;
750 node = (EphemeronLinkNode *)sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
755 node->array = (MonoArray*)obj;
756 node->next = ephemeron_list;
757 ephemeron_list = node;
759 SGEN_LOG (5, "Registered ephemeron array %p", obj);
770 need_remove_object_for_domain (GCObject *start, MonoDomain *domain)
772 if (mono_object_domain (start) == domain) {
773 SGEN_LOG (4, "Need to cleanup object %p", start);
774 binary_protocol_cleanup (start, (gpointer)SGEN_LOAD_VTABLE (start), sgen_safe_object_get_size ((GCObject*)start));
781 process_object_for_domain_clearing (GCObject *start, MonoDomain *domain)
783 MonoVTable *vt = SGEN_LOAD_VTABLE (start);
784 if (vt->klass == mono_defaults.internal_thread_class)
785 g_assert (mono_object_domain (start) == mono_get_root_domain ());
786 /* The object could be a proxy for an object in the domain
788 #ifndef DISABLE_REMOTING
789 if (mono_defaults.real_proxy_class->supertypes && mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
790 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
792 /* The server could already have been zeroed out, so
793 we need to check for that, too. */
794 if (server && (!SGEN_LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
795 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
796 ((MonoRealProxy*)start)->unwrapped_server = NULL;
803 clear_domain_process_object (GCObject *obj, MonoDomain *domain)
807 process_object_for_domain_clearing (obj, domain);
808 remove = need_remove_object_for_domain (obj, domain);
810 if (remove && obj->synchronisation) {
811 guint32 dislink = mono_monitor_get_object_monitor_gchandle (obj);
813 mono_gchandle_free (dislink);
820 clear_domain_process_minor_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
822 if (clear_domain_process_object (obj, domain)) {
823 CANARIFY_SIZE (size);
824 memset (obj, 0, size);
829 clear_domain_process_major_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
831 clear_domain_process_object (obj, domain);
835 clear_domain_free_major_non_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
837 if (need_remove_object_for_domain (obj, domain))
838 major_collector.free_non_pinned_object (obj, size);
842 clear_domain_free_major_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
844 if (need_remove_object_for_domain (obj, domain))
845 major_collector.free_pinned_object (obj, size);
849 * When appdomains are unloaded we can easily remove objects that have finalizers,
850 * but all the others could still be present in random places on the heap.
851 * We need a sweep to get rid of them even though it's going to be costly
853 * The reason we need to remove them is because we access the vtable and class
854 * structures to know the object size and the reference bitmap: once the domain is
855 * unloaded the point to random memory.
858 mono_gc_clear_domain (MonoDomain * domain)
860 LOSObject *bigobj, *prev;
865 binary_protocol_domain_unload_begin (domain);
869 if (sgen_concurrent_collection_in_progress ())
870 sgen_perform_collection (0, GENERATION_OLD, "clear domain", TRUE, FALSE);
871 SGEN_ASSERT (0, !sgen_concurrent_collection_in_progress (), "We just ordered a synchronous collection. Why are we collecting concurrently?");
873 major_collector.finish_sweeping ();
875 sgen_process_fin_stage_entries ();
877 sgen_clear_nursery_fragments ();
879 if (sgen_mono_xdomain_checks && domain != mono_get_root_domain ()) {
880 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
881 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
882 sgen_check_for_xdomain_refs ();
885 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
886 to memory returned to the OS.*/
887 null_ephemerons_for_domain (domain);
888 sgen_null_links_for_domain (domain);
890 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
891 sgen_remove_finalizers_if (object_in_domain_predicate, domain, i);
893 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
894 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE, TRUE);
896 /* We need two passes over major and large objects because
897 freeing such objects might give their memory back to the OS
898 (in the case of large objects) or obliterate its vtable
899 (pinned objects with major-copying or pinned and non-pinned
900 objects with major-mark&sweep), but we might need to
901 dereference a pointer from an object to another object if
902 the first object is a proxy. */
903 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
904 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
905 clear_domain_process_object ((GCObject*)bigobj->data, domain);
908 for (bigobj = los_object_list; bigobj;) {
909 if (need_remove_object_for_domain ((GCObject*)bigobj->data, domain)) {
910 LOSObject *to_free = bigobj;
912 prev->next = bigobj->next;
914 los_object_list = bigobj->next;
915 bigobj = bigobj->next;
916 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
917 sgen_los_free_object (to_free);
921 bigobj = bigobj->next;
923 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
924 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
926 if (domain == mono_get_root_domain ()) {
927 sgen_pin_stats_report ();
928 sgen_object_layout_dump (stdout);
931 sgen_restart_world (0);
933 binary_protocol_domain_unload_end (domain);
934 binary_protocol_flush_buffers (FALSE);
944 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
946 MonoObject *obj = sgen_alloc_obj (vtable, size);
948 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS)) {
950 mono_profiler_allocation (obj);
957 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
959 MonoObject *obj = sgen_alloc_obj_pinned (vtable, size);
961 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS)) {
963 mono_profiler_allocation (obj);
970 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
972 MonoObject *obj = sgen_alloc_obj_mature (vtable, size);
974 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS)) {
976 mono_profiler_allocation (obj);
983 mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
985 /* FIXME: do a single allocation */
986 void *res = g_calloc (1, size);
989 if (!mono_gc_register_root ((char *)res, size, descr, source, msg)) {
997 mono_gc_free_fixed (void* addr)
999 mono_gc_deregister_root ((char *)addr);
1007 static MonoMethod* alloc_method_cache [ATYPE_NUM];
1008 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
1009 static gboolean use_managed_allocator = TRUE;
1011 #ifdef MANAGED_ALLOCATION
1012 // Cache the SgenThreadInfo pointer in a local 'var'.
1013 #define EMIT_TLS_ACCESS_VAR(mb, var) \
1015 var = mono_mb_add_local ((mb), &mono_defaults.int_class->byval_arg); \
1016 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1017 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1018 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_THREAD_INFO); \
1019 mono_mb_emit_stloc ((mb), (var)); \
1022 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, var) \
1024 mono_mb_emit_ldloc ((mb), (var)); \
1025 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenClientThreadInfo, in_critical_region)); \
1026 mono_mb_emit_byte ((mb), CEE_ADD); \
1029 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, var) do { \
1030 mono_mb_emit_ldloc ((mb), (var)); \
1031 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_next)); \
1032 mono_mb_emit_byte ((mb), CEE_ADD); \
1035 #define EMIT_TLS_ACCESS_TEMP_END(mb, var) do { \
1036 mono_mb_emit_ldloc ((mb), (var)); \
1037 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_temp_end)); \
1038 mono_mb_emit_byte ((mb), CEE_ADD); \
1039 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1042 /* FIXME: Do this in the JIT, where specialized allocation sequences can be created
1043 * for each class. This is currently not easy to do, as it is hard to generate basic
1044 * blocks + branches, but it is easy with the linear IL codebase.
1046 * For this to work we'd need to solve the TLAB race, first. Now we
1047 * require the allocator to be in a few known methods to make sure
1048 * that they are executed atomically via the restart mechanism.
1051 create_allocator (int atype, ManagedAllocatorVariant variant)
1053 int p_var, size_var, real_size_var, thread_var G_GNUC_UNUSED;
1054 gboolean slowpath = variant == MANAGED_ALLOCATOR_SLOW_PATH;
1055 guint32 slowpath_branch, max_size_branch;
1056 MonoMethodBuilder *mb;
1058 MonoMethodSignature *csig;
1059 static gboolean registered = FALSE;
1060 int tlab_next_addr_var, new_next_var;
1061 const char *name = NULL;
1066 mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
1067 mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
1068 mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE);
1072 if (atype == ATYPE_SMALL) {
1073 name = slowpath ? "SlowAllocSmall" : "AllocSmall";
1074 } else if (atype == ATYPE_NORMAL) {
1075 name = slowpath ? "SlowAlloc" : "Alloc";
1076 } else if (atype == ATYPE_VECTOR) {
1077 name = slowpath ? "SlowAllocVector" : "AllocVector";
1078 } else if (atype == ATYPE_STRING) {
1079 name = slowpath ? "SlowAllocString" : "AllocString";
1081 g_assert_not_reached ();
1084 if (atype == ATYPE_NORMAL)
1089 csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
1090 if (atype == ATYPE_STRING) {
1091 csig->ret = &mono_defaults.string_class->byval_arg;
1092 csig->params [0] = &mono_defaults.int_class->byval_arg;
1093 csig->params [1] = &mono_defaults.int32_class->byval_arg;
1095 csig->ret = &mono_defaults.object_class->byval_arg;
1096 for (i = 0; i < num_params; i++)
1097 csig->params [i] = &mono_defaults.int_class->byval_arg;
1100 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
1107 mono_mb_emit_ldarg (mb, 0);
1108 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1111 mono_mb_emit_ldarg (mb, 0);
1112 mono_mb_emit_ldarg (mb, 1);
1113 mono_mb_emit_icall (mb, ves_icall_array_new_specific);
1116 mono_mb_emit_ldarg (mb, 1);
1117 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1120 g_assert_not_reached ();
1127 * Tls access might call foreign code or code without jinfo. This can
1128 * only happen if we are outside of the critical region.
1130 EMIT_TLS_ACCESS_VAR (mb, thread_var);
1132 size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1133 if (atype == ATYPE_SMALL) {
1134 /* size_var = size_arg */
1135 mono_mb_emit_ldarg (mb, 1);
1136 mono_mb_emit_stloc (mb, size_var);
1137 } else if (atype == ATYPE_NORMAL) {
1138 /* size = vtable->klass->instance_size; */
1139 mono_mb_emit_ldarg (mb, 0);
1140 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1141 mono_mb_emit_byte (mb, CEE_ADD);
1142 mono_mb_emit_byte (mb, CEE_LDIND_I);
1143 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, instance_size));
1144 mono_mb_emit_byte (mb, CEE_ADD);
1145 /* FIXME: assert instance_size stays a 4 byte integer */
1146 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1147 mono_mb_emit_byte (mb, CEE_CONV_I);
1148 mono_mb_emit_stloc (mb, size_var);
1149 } else if (atype == ATYPE_VECTOR) {
1150 MonoExceptionClause *clause;
1151 int pos, pos_leave, pos_error;
1152 MonoClass *oom_exc_class;
1156 * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException
1157 * n < 0 => OverflowException
1159 * We can do an unsigned comparison to catch both cases, then in the error
1160 * case compare signed to distinguish between them.
1162 mono_mb_emit_ldarg (mb, 1);
1163 mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
1164 mono_mb_emit_byte (mb, CEE_CONV_U);
1165 pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
1167 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1168 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1169 mono_mb_emit_ldarg (mb, 1);
1170 mono_mb_emit_icon (mb, 0);
1171 pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S);
1172 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1173 mono_mb_patch_short_branch (mb, pos_error);
1174 mono_mb_emit_exception (mb, "OverflowException", NULL);
1176 mono_mb_patch_short_branch (mb, pos);
1178 clause = (MonoExceptionClause *)mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
1179 clause->try_offset = mono_mb_get_label (mb);
1181 /* vtable->klass->sizes.element_size */
1182 mono_mb_emit_ldarg (mb, 0);
1183 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1184 mono_mb_emit_byte (mb, CEE_ADD);
1185 mono_mb_emit_byte (mb, CEE_LDIND_I);
1186 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, sizes));
1187 mono_mb_emit_byte (mb, CEE_ADD);
1188 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1189 mono_mb_emit_byte (mb, CEE_CONV_I);
1192 mono_mb_emit_ldarg (mb, 1);
1193 mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
1194 /* + sizeof (MonoArray) */
1195 mono_mb_emit_icon (mb, MONO_SIZEOF_MONO_ARRAY);
1196 mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
1197 mono_mb_emit_stloc (mb, size_var);
1199 pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);
1202 clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
1203 clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
1204 clause->data.catch_class = mono_class_load_from_name (mono_defaults.corlib,
1205 "System", "OverflowException");
1206 clause->handler_offset = mono_mb_get_label (mb);
1208 oom_exc_class = mono_class_load_from_name (mono_defaults.corlib,
1209 "System", "OutOfMemoryException");
1210 ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
1213 mono_mb_emit_byte (mb, CEE_POP);
1214 mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
1215 mono_mb_emit_byte (mb, CEE_THROW);
1217 clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
1218 mono_mb_set_clauses (mb, 1, clause);
1219 mono_mb_patch_branch (mb, pos_leave);
1221 } else if (atype == ATYPE_STRING) {
1225 * a string allocator method takes the args: (vtable, len)
1227 * bytes = offsetof (MonoString, chars) + ((len + 1) * 2)
1231 * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1235 * offsetof (MonoString, chars) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1236 * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - offsetof (MonoString, chars)) / 2 - 1
1238 mono_mb_emit_ldarg (mb, 1);
1239 mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - MONO_STRUCT_OFFSET (MonoString, chars)) / 2 - 1);
1240 pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
1242 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1243 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1244 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1245 mono_mb_patch_short_branch (mb, pos);
1247 mono_mb_emit_ldarg (mb, 1);
1248 mono_mb_emit_icon (mb, 1);
1249 mono_mb_emit_byte (mb, MONO_CEE_SHL);
1250 //WE manually fold the above + 2 here
1251 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, chars) + 2);
1252 mono_mb_emit_byte (mb, CEE_ADD);
1253 mono_mb_emit_stloc (mb, size_var);
1255 g_assert_not_reached ();
1258 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1259 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1260 mono_mb_emit_byte (mb, CEE_LDC_I4_1);
1261 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1262 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1263 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1266 if (nursery_canaries_enabled ()) {
1267 real_size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1268 mono_mb_emit_ldloc (mb, size_var);
1269 mono_mb_emit_stloc(mb, real_size_var);
1272 real_size_var = size_var;
1274 /* size += ALLOC_ALIGN - 1; */
1275 mono_mb_emit_ldloc (mb, size_var);
1276 mono_mb_emit_icon (mb, SGEN_ALLOC_ALIGN - 1);
1277 mono_mb_emit_byte (mb, CEE_ADD);
1278 /* size &= ~(ALLOC_ALIGN - 1); */
1279 mono_mb_emit_icon (mb, ~(SGEN_ALLOC_ALIGN - 1));
1280 mono_mb_emit_byte (mb, CEE_AND);
1281 mono_mb_emit_stloc (mb, size_var);
1283 /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
1284 if (atype != ATYPE_SMALL) {
1285 mono_mb_emit_ldloc (mb, size_var);
1286 mono_mb_emit_icon (mb, SGEN_MAX_SMALL_OBJ_SIZE);
1287 max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
1291 * We need to modify tlab_next, but the JIT only supports reading, so we read
1292 * another tls var holding its address instead.
1295 /* tlab_next_addr (local) = tlab_next_addr (TLS var) */
1296 tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1297 EMIT_TLS_ACCESS_NEXT_ADDR (mb, thread_var);
1298 mono_mb_emit_stloc (mb, tlab_next_addr_var);
1300 /* p = (void**)tlab_next; */
1301 p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1302 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1303 mono_mb_emit_byte (mb, CEE_LDIND_I);
1304 mono_mb_emit_stloc (mb, p_var);
1306 /* new_next = (char*)p + size; */
1307 new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1308 mono_mb_emit_ldloc (mb, p_var);
1309 mono_mb_emit_ldloc (mb, size_var);
1310 mono_mb_emit_byte (mb, CEE_CONV_I);
1311 mono_mb_emit_byte (mb, CEE_ADD);
1313 if (nursery_canaries_enabled ()) {
1314 mono_mb_emit_icon (mb, CANARY_SIZE);
1315 mono_mb_emit_byte (mb, CEE_ADD);
1317 mono_mb_emit_stloc (mb, new_next_var);
1319 /* if (G_LIKELY (new_next < tlab_temp_end)) */
1320 mono_mb_emit_ldloc (mb, new_next_var);
1321 EMIT_TLS_ACCESS_TEMP_END (mb, thread_var);
1322 slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1325 if (atype != ATYPE_SMALL)
1326 mono_mb_patch_short_branch (mb, max_size_branch);
1328 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1329 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1331 * We are no longer in a critical section. We need to do this before calling
1332 * to unmanaged land in order to avoid stw deadlocks since unmanaged code
1335 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1336 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1337 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1338 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1339 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1340 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1343 /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
1344 mono_mb_emit_ldarg (mb, 0);
1345 mono_mb_emit_ldloc (mb, real_size_var);
1346 if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
1347 mono_mb_emit_icall (mb, mono_gc_alloc_obj);
1348 } else if (atype == ATYPE_VECTOR) {
1349 mono_mb_emit_ldarg (mb, 1);
1350 mono_mb_emit_icall (mb, mono_gc_alloc_vector);
1351 } else if (atype == ATYPE_STRING) {
1352 mono_mb_emit_ldarg (mb, 1);
1353 mono_mb_emit_icall (mb, mono_gc_alloc_string);
1355 g_assert_not_reached ();
1357 mono_mb_emit_byte (mb, CEE_RET);
1360 mono_mb_patch_short_branch (mb, slowpath_branch);
1362 /* FIXME: Memory barrier */
1364 /* tlab_next = new_next */
1365 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1366 mono_mb_emit_ldloc (mb, new_next_var);
1367 mono_mb_emit_byte (mb, CEE_STIND_I);
1370 mono_mb_emit_ldloc (mb, p_var);
1371 mono_mb_emit_ldarg (mb, 0);
1372 mono_mb_emit_byte (mb, CEE_STIND_I);
1374 /* mark object end with nursery word */
1375 if (nursery_canaries_enabled ()) {
1376 mono_mb_emit_ldloc (mb, p_var);
1377 mono_mb_emit_ldloc (mb, real_size_var);
1378 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1379 mono_mb_emit_icon8 (mb, (mword) CANARY_STRING);
1380 mono_mb_emit_icon (mb, CANARY_SIZE);
1381 mono_mb_emit_byte (mb, MONO_CEE_PREFIX1);
1382 mono_mb_emit_byte (mb, CEE_CPBLK);
1385 if (atype == ATYPE_VECTOR) {
1386 /* arr->max_length = max_length; */
1387 mono_mb_emit_ldloc (mb, p_var);
1388 mono_mb_emit_ldflda (mb, MONO_STRUCT_OFFSET (MonoArray, max_length));
1389 mono_mb_emit_ldarg (mb, 1);
1390 #ifdef MONO_BIG_ARRAYS
1391 mono_mb_emit_byte (mb, CEE_STIND_I);
1393 mono_mb_emit_byte (mb, CEE_STIND_I4);
1395 } else if (atype == ATYPE_STRING) {
1396 /* need to set length and clear the last char */
1397 /* s->length = len; */
1398 mono_mb_emit_ldloc (mb, p_var);
1399 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, length));
1400 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1401 mono_mb_emit_ldarg (mb, 1);
1402 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1405 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1406 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1407 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1408 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1409 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1411 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1412 mono_mb_emit_byte (mb, CEE_MONO_MEMORY_BARRIER);
1415 We must make sure both vtable and max_length are globaly visible before returning to managed land.
1417 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_REL);
1420 mono_mb_emit_ldloc (mb, p_var);
1423 mono_mb_emit_byte (mb, CEE_RET);
1426 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1427 info->d.alloc.gc_name = "sgen";
1428 info->d.alloc.alloc_type = atype;
1431 mb->init_locals = FALSE;
1434 res = mono_mb_create (mb, csig, 8, info);
1443 mono_gc_get_aligned_size_for_allocator (int size)
1445 return SGEN_ALIGN_UP (size);
1449 * Generate an allocator method implementing the fast path of mono_gc_alloc_obj ().
1450 * The signature of the called method is:
1451 * object allocate (MonoVTable *vtable)
1454 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1456 #ifdef MANAGED_ALLOCATION
1457 if (collect_before_allocs)
1459 if (klass->instance_size > tlab_size)
1461 if (known_instance_size && ALIGN_TO (klass->instance_size, SGEN_ALLOC_ALIGN) >= SGEN_MAX_SMALL_OBJ_SIZE)
1463 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1467 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1469 if (klass->byval_arg.type == MONO_TYPE_STRING)
1470 return mono_gc_get_managed_allocator_by_type (ATYPE_STRING, MANAGED_ALLOCATOR_REGULAR);
1471 /* Generic classes have dynamic field and can go above MAX_SMALL_OBJ_SIZE. */
1472 if (known_instance_size)
1473 return mono_gc_get_managed_allocator_by_type (ATYPE_SMALL, MANAGED_ALLOCATOR_REGULAR);
1475 return mono_gc_get_managed_allocator_by_type (ATYPE_NORMAL, MANAGED_ALLOCATOR_REGULAR);
1482 mono_gc_get_managed_array_allocator (MonoClass *klass)
1484 #ifdef MANAGED_ALLOCATION
1485 if (klass->rank != 1)
1487 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1489 if (has_per_allocation_action)
1491 g_assert (!mono_class_has_finalizer (klass) && !mono_class_is_marshalbyref (klass));
1493 return mono_gc_get_managed_allocator_by_type (ATYPE_VECTOR, MANAGED_ALLOCATOR_REGULAR);
1500 sgen_set_use_managed_allocator (gboolean flag)
1502 use_managed_allocator = flag;
1506 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1508 #ifdef MANAGED_ALLOCATION
1512 if (variant == MANAGED_ALLOCATOR_REGULAR && !use_managed_allocator)
1516 case MANAGED_ALLOCATOR_REGULAR: cache = alloc_method_cache; break;
1517 case MANAGED_ALLOCATOR_SLOW_PATH: cache = slowpath_alloc_method_cache; break;
1518 default: g_assert_not_reached (); break;
1521 res = cache [atype];
1525 res = create_allocator (atype, variant);
1527 if (cache [atype]) {
1528 mono_free_method (res);
1529 res = cache [atype];
1531 mono_memory_barrier ();
1532 cache [atype] = res;
1543 mono_gc_get_managed_allocator_types (void)
1549 sgen_is_managed_allocator (MonoMethod *method)
1553 for (i = 0; i < ATYPE_NUM; ++i)
1554 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1560 sgen_has_managed_allocator (void)
1564 for (i = 0; i < ATYPE_NUM; ++i)
1565 if (alloc_method_cache [i] || slowpath_alloc_method_cache [i])
1571 * Cardtable scanning
1574 #define MWORD_MASK (sizeof (mword) - 1)
1577 find_card_offset (mword card)
1579 /*XXX Use assembly as this generates some pretty bad code */
1580 #if defined(__i386__) && defined(__GNUC__)
1581 return (__builtin_ffs (card) - 1) / 8;
1582 #elif defined(__x86_64__) && defined(__GNUC__)
1583 return (__builtin_ffsll (card) - 1) / 8;
1584 #elif defined(__s390x__)
1585 return (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1588 guint8 *ptr = (guint8 *) &card;
1589 for (i = 0; i < sizeof (mword); ++i) {
1598 find_next_card (guint8 *card_data, guint8 *end)
1600 mword *cards, *cards_end;
1603 while ((((mword)card_data) & MWORD_MASK) && card_data < end) {
1609 if (card_data == end)
1612 cards = (mword*)card_data;
1613 cards_end = (mword*)((mword)end & ~MWORD_MASK);
1614 while (cards < cards_end) {
1617 return (guint8*)cards + find_card_offset (card);
1621 card_data = (guint8*)cards_end;
1622 while (card_data < end) {
1631 #define ARRAY_OBJ_INDEX(ptr,array,elem_size) (((char*)(ptr) - ((char*)(array) + G_STRUCT_OFFSET (MonoArray, vector))) / (elem_size))
1634 sgen_client_cardtable_scan_object (GCObject *obj, mword block_obj_size, guint8 *cards, ScanCopyContext ctx)
1636 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
1637 MonoClass *klass = vt->klass;
1639 SGEN_ASSERT (0, SGEN_VTABLE_HAS_REFERENCES (vt), "Why would we ever call this on reference-free objects?");
1642 MonoArray *arr = (MonoArray*)obj;
1643 guint8 *card_data, *card_base;
1644 guint8 *card_data_end;
1645 char *obj_start = (char *)sgen_card_table_align_pointer (obj);
1647 mword obj_size = sgen_mono_array_size (vt, arr, &bounds_size, sgen_vtable_get_descriptor (vt));
1648 /* We don't want to scan the bounds entries at the end of multidimensional arrays */
1649 char *obj_end = (char*)obj + obj_size - bounds_size;
1651 size_t extra_idx = 0;
1653 mword desc = (mword)klass->element_class->gc_descr;
1654 int elem_size = mono_array_element_size (klass);
1656 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1657 guint8 *overflow_scan_end = NULL;
1660 #ifdef SGEN_OBJECT_LAYOUT_STATISTICS
1661 if (klass->element_class->valuetype)
1662 sgen_object_layout_scanned_vtype_array ();
1664 sgen_object_layout_scanned_ref_array ();
1670 card_data = sgen_card_table_get_card_scan_address ((mword)obj);
1672 card_base = card_data;
1673 card_count = sgen_card_table_number_of_cards_in_range ((mword)obj, obj_size);
1674 card_data_end = card_data + card_count;
1677 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1678 /*Check for overflow and if so, setup to scan in two steps*/
1679 if (!cards && card_data_end >= SGEN_SHADOW_CARDTABLE_END) {
1680 overflow_scan_end = sgen_shadow_cardtable + (card_data_end - SGEN_SHADOW_CARDTABLE_END);
1681 card_data_end = SGEN_SHADOW_CARDTABLE_END;
1687 card_data = find_next_card (card_data, card_data_end);
1688 for (; card_data < card_data_end; card_data = find_next_card (card_data + 1, card_data_end)) {
1690 size_t idx = (card_data - card_base) + extra_idx;
1691 char *start = (char*)(obj_start + idx * CARD_SIZE_IN_BYTES);
1692 char *card_end = start + CARD_SIZE_IN_BYTES;
1693 char *first_elem, *elem;
1695 HEAVY_STAT (++los_marked_cards);
1698 sgen_card_table_prepare_card_for_scanning (card_data);
1700 card_end = MIN (card_end, obj_end);
1702 if (start <= (char*)arr->vector)
1705 index = ARRAY_OBJ_INDEX (start, obj, elem_size);
1707 elem = first_elem = (char*)mono_array_addr_with_size_fast ((MonoArray*)obj, elem_size, index);
1708 if (klass->element_class->valuetype) {
1709 ScanVTypeFunc scan_vtype_func = ctx.ops->scan_vtype;
1711 for (; elem < card_end; elem += elem_size)
1712 scan_vtype_func (obj, elem, desc, ctx.queue BINARY_PROTOCOL_ARG (elem_size));
1714 ScanPtrFieldFunc scan_ptr_field_func = ctx.ops->scan_ptr_field;
1716 HEAVY_STAT (++los_array_cards);
1717 for (; elem < card_end; elem += SIZEOF_VOID_P)
1718 scan_ptr_field_func (obj, (GCObject**)elem, ctx.queue);
1721 binary_protocol_card_scan (first_elem, elem - first_elem);
1724 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1725 if (overflow_scan_end) {
1726 extra_idx = card_data - card_base;
1727 card_base = card_data = sgen_shadow_cardtable;
1728 card_data_end = overflow_scan_end;
1729 overflow_scan_end = NULL;
1740 * Array and string allocation
1744 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
1749 if (!SGEN_CAN_ALIGN_UP (size))
1752 #ifndef DISABLE_CRITICAL_REGION
1753 ENTER_CRITICAL_REGION;
1754 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1756 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1757 arr->max_length = (mono_array_size_t)max_length;
1758 EXIT_CRITICAL_REGION;
1761 EXIT_CRITICAL_REGION;
1766 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1767 if (G_UNLIKELY (!arr)) {
1772 arr->max_length = (mono_array_size_t)max_length;
1777 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
1778 mono_profiler_allocation (&arr->obj);
1780 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Vector has incorrect size.");
1785 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
1788 MonoArrayBounds *bounds;
1791 if (!SGEN_CAN_ALIGN_UP (size))
1794 #ifndef DISABLE_CRITICAL_REGION
1795 ENTER_CRITICAL_REGION;
1796 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1798 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1799 arr->max_length = (mono_array_size_t)max_length;
1801 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1802 arr->bounds = bounds;
1803 EXIT_CRITICAL_REGION;
1806 EXIT_CRITICAL_REGION;
1811 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1812 if (G_UNLIKELY (!arr)) {
1817 arr->max_length = (mono_array_size_t)max_length;
1819 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1820 arr->bounds = bounds;
1825 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
1826 mono_profiler_allocation (&arr->obj);
1828 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Array has incorrect size.");
1833 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
1838 if (!SGEN_CAN_ALIGN_UP (size))
1841 #ifndef DISABLE_CRITICAL_REGION
1842 ENTER_CRITICAL_REGION;
1843 str = (MonoString*)sgen_try_alloc_obj_nolock (vtable, size);
1845 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1847 EXIT_CRITICAL_REGION;
1850 EXIT_CRITICAL_REGION;
1855 str = (MonoString*)sgen_alloc_obj_nolock (vtable, size);
1856 if (G_UNLIKELY (!str)) {
1866 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
1867 mono_profiler_allocation (&str->object);
1877 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1879 mono_unichar2 *new_end = str->chars + new_length;
1881 /* zero the discarded string. This null-delimits the string and allows
1882 * the space to be reclaimed by SGen. */
1884 if (nursery_canaries_enabled () && sgen_ptr_in_nursery (str)) {
1885 CHECK_CANARY_FOR_OBJECT ((GCObject*)str, TRUE);
1886 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2) + CANARY_SIZE);
1887 memcpy (new_end + 1 , CANARY_STRING, CANARY_SIZE);
1889 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1892 str->length = new_length;
1899 #define GC_ROOT_NUM 32
1901 int count; /* must be the first field */
1902 void *objects [GC_ROOT_NUM];
1903 int root_types [GC_ROOT_NUM];
1904 uintptr_t extra_info [GC_ROOT_NUM];
1908 notify_gc_roots (GCRootReport *report)
1912 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
1917 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
1919 if (report->count == GC_ROOT_NUM)
1920 notify_gc_roots (report);
1921 report->objects [report->count] = object;
1922 report->root_types [report->count] = rtype;
1923 report->extra_info [report->count++] = (uintptr_t)SGEN_LOAD_VTABLE (object)->klass;
1927 sgen_client_nursery_objects_pinned (void **definitely_pinned, int count)
1929 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1930 GCRootReport report;
1933 for (idx = 0; idx < count; ++idx)
1934 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1935 notify_gc_roots (&report);
1940 report_finalizer_roots_from_queue (SgenPointerQueue *queue)
1942 GCRootReport report;
1946 for (i = 0; i < queue->next_slot; ++i) {
1947 void *obj = queue->data [i];
1950 add_profile_gc_root (&report, obj, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1952 notify_gc_roots (&report);
1956 report_finalizer_roots (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
1958 report_finalizer_roots_from_queue (fin_ready_queue);
1959 report_finalizer_roots_from_queue (critical_fin_queue);
1962 static GCRootReport *root_report;
1965 single_arg_report_root (MonoObject **obj, void *gc_data)
1968 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1972 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1974 switch (desc & ROOT_DESC_TYPE_MASK) {
1975 case ROOT_DESC_BITMAP:
1976 desc >>= ROOT_DESC_TYPE_SHIFT;
1978 if ((desc & 1) && *start_root) {
1979 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1985 case ROOT_DESC_COMPLEX: {
1986 gsize *bitmap_data = (gsize *)sgen_get_complex_descriptor_bitmap (desc);
1987 gsize bwords = (*bitmap_data) - 1;
1988 void **start_run = start_root;
1990 while (bwords-- > 0) {
1991 gsize bmap = *bitmap_data++;
1992 void **objptr = start_run;
1994 if ((bmap & 1) && *objptr) {
1995 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
2000 start_run += GC_BITS_PER_WORD;
2004 case ROOT_DESC_USER: {
2005 MonoGCRootMarkFunc marker = (MonoGCRootMarkFunc)sgen_get_user_descriptor_func (desc);
2006 root_report = report;
2007 marker ((MonoObject**)start_root, single_arg_report_root, NULL);
2010 case ROOT_DESC_RUN_LEN:
2011 g_assert_not_reached ();
2013 g_assert_not_reached ();
2018 report_registered_roots_by_type (int root_type)
2020 GCRootReport report;
2024 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], void **, start_root, RootRecord *, root) {
2025 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
2026 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
2027 } SGEN_HASH_TABLE_FOREACH_END;
2028 notify_gc_roots (&report);
2032 report_registered_roots (void)
2034 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
2035 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
2039 sgen_client_collecting_minor (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2041 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2042 report_registered_roots ();
2043 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2044 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2047 static GCRootReport major_root_report;
2048 static gboolean profile_roots;
2051 sgen_client_collecting_major_1 (void)
2053 profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2054 memset (&major_root_report, 0, sizeof (GCRootReport));
2058 sgen_client_pinned_los_object (GCObject *obj)
2061 add_profile_gc_root (&major_root_report, (char*)obj, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2065 sgen_client_collecting_major_2 (void)
2068 notify_gc_roots (&major_root_report);
2070 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2071 report_registered_roots ();
2075 sgen_client_collecting_major_3 (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2077 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2078 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2081 #define MOVED_OBJECTS_NUM 64
2082 static void *moved_objects [MOVED_OBJECTS_NUM];
2083 static int moved_objects_idx = 0;
2085 static SgenPointerQueue moved_objects_queue = SGEN_POINTER_QUEUE_INIT (INTERNAL_MEM_MOVED_OBJECT);
2088 mono_sgen_register_moved_object (void *obj, void *destination)
2091 * This function can be called from SGen's worker threads. We want to try
2092 * and avoid exposing those threads to the profiler API, so queue up move
2093 * events and send them later when the main GC thread calls
2094 * mono_sgen_gc_event_moves ().
2096 * TODO: Once SGen has multiple worker threads, we need to switch to a
2097 * lock-free data structure for the queue as multiple threads will be
2098 * adding to it at the same time.
2100 if (sgen_thread_pool_is_thread_pool_thread (mono_native_thread_id_get ())) {
2101 sgen_pointer_queue_add (&moved_objects_queue, obj);
2102 sgen_pointer_queue_add (&moved_objects_queue, destination);
2104 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2105 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2106 moved_objects_idx = 0;
2109 moved_objects [moved_objects_idx++] = obj;
2110 moved_objects [moved_objects_idx++] = destination;
2115 mono_sgen_gc_event_moves (void)
2117 while (!sgen_pointer_queue_is_empty (&moved_objects_queue)) {
2118 void *dst = sgen_pointer_queue_pop (&moved_objects_queue);
2119 void *src = sgen_pointer_queue_pop (&moved_objects_queue);
2121 mono_sgen_register_moved_object (src, dst);
2124 if (moved_objects_idx) {
2125 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2126 moved_objects_idx = 0;
2134 #define REFS_SIZE 128
2137 MonoGCReferences callback;
2141 MonoObject *refs [REFS_SIZE];
2142 uintptr_t offsets [REFS_SIZE];
2146 #define HANDLE_PTR(ptr,obj) do { \
2148 if (hwi->count == REFS_SIZE) { \
2149 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
2153 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
2154 hwi->refs [hwi->count++] = *(ptr); \
2159 collect_references (HeapWalkInfo *hwi, GCObject *obj, size_t size)
2161 char *start = (char*)obj;
2162 mword desc = sgen_obj_get_descriptor (obj);
2164 #include "sgen/sgen-scan-object.h"
2168 walk_references (GCObject *start, size_t size, void *data)
2170 HeapWalkInfo *hwi = (HeapWalkInfo *)data;
2173 collect_references (hwi, start, size);
2174 if (hwi->count || !hwi->called)
2175 hwi->callback (start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
2179 * mono_gc_walk_heap:
2180 * @flags: flags for future use
2181 * @callback: a function pointer called for each object in the heap
2182 * @data: a user data pointer that is passed to callback
2184 * This function can be used to iterate over all the live objects in the heap:
2185 * for each object, @callback is invoked, providing info about the object's
2186 * location in memory, its class, its size and the objects it references.
2187 * For each referenced object it's offset from the object address is
2188 * reported in the offsets array.
2189 * The object references may be buffered, so the callback may be invoked
2190 * multiple times for the same object: in all but the first call, the size
2191 * argument will be zero.
2192 * Note that this function can be only called in the #MONO_GC_EVENT_PRE_START_WORLD
2193 * profiler event handler.
2195 * Returns: a non-zero value if the GC doesn't support heap walking
2198 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
2203 hwi.callback = callback;
2206 sgen_clear_nursery_fragments ();
2207 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE, TRUE);
2209 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, walk_references, &hwi);
2210 sgen_los_iterate_objects (walk_references, &hwi);
2220 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
2222 gc_callbacks = *callbacks;
2226 mono_gc_get_gc_callbacks ()
2228 return &gc_callbacks;
2232 sgen_client_thread_register (SgenThreadInfo* info, void *stack_bottom_fallback)
2235 guint8 *staddr = NULL;
2237 mono_tls_set_sgen_thread_info (info);
2239 info->client_info.skip = 0;
2241 info->client_info.stack_start = NULL;
2243 #ifdef SGEN_POSIX_STW
2244 info->client_info.stop_count = -1;
2245 info->client_info.signal = 0;
2248 mono_thread_info_get_stack_bounds (&staddr, &stsize);
2250 info->client_info.stack_start_limit = staddr;
2251 info->client_info.stack_end = staddr + stsize;
2253 gsize stack_bottom = (gsize)stack_bottom_fallback;
2254 stack_bottom += 4095;
2255 stack_bottom &= ~4095;
2256 info->client_info.stack_end = (char*)stack_bottom;
2259 memset (&info->client_info.ctx, 0, sizeof (MonoContext));
2261 if (mono_gc_get_gc_callbacks ()->thread_attach_func)
2262 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2264 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
2266 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->client_info.stack_end);
2268 info->client_info.info.handle_stack = mono_handle_stack_alloc ();
2272 sgen_client_thread_unregister (SgenThreadInfo *p)
2274 MonoNativeThreadId tid;
2276 mono_tls_set_sgen_thread_info (NULL);
2278 tid = mono_thread_info_get_tid (p);
2280 if (p->client_info.info.runtime_thread)
2281 mono_threads_add_joinable_thread ((gpointer)tid);
2283 if (mono_gc_get_gc_callbacks ()->thread_detach_func) {
2284 mono_gc_get_gc_callbacks ()->thread_detach_func (p->client_info.runtime_data);
2285 p->client_info.runtime_data = NULL;
2288 binary_protocol_thread_unregister ((gpointer)tid);
2289 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)tid);
2291 HandleStack *handles = (HandleStack*) p->client_info.info.handle_stack;
2292 p->client_info.info.handle_stack = NULL;
2293 mono_handle_stack_free (handles);
2297 mono_gc_set_skip_thread (gboolean skip)
2299 SgenThreadInfo *info = mono_thread_info_current ();
2302 info->client_info.gc_disabled = skip;
2307 thread_in_critical_region (SgenThreadInfo *info)
2309 return info->client_info.in_critical_region;
2313 sgen_thread_attach (SgenThreadInfo *info)
2315 if (mono_gc_get_gc_callbacks ()->thread_attach_func && !info->client_info.runtime_data)
2316 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2320 sgen_thread_detach (SgenThreadInfo *p)
2322 /* If a delegate is passed to native code and invoked on a thread we dont
2323 * know about, marshal will register it with mono_threads_attach_coop, but
2324 * we have no way of knowing when that thread goes away. SGen has a TSD
2325 * so we assume that if the domain is still registered, we can detach
2328 if (mono_thread_internal_current_is_attached ())
2329 mono_thread_detach_internal (mono_thread_internal_current ());
2333 mono_gc_register_thread (void *baseptr)
2335 return mono_thread_info_attach (baseptr) != NULL;
2339 mono_gc_is_gc_thread (void)
2343 result = mono_thread_info_current () != NULL;
2349 sgen_client_thread_register_worker (void)
2351 mono_thread_info_register_small_id ();
2352 mono_native_thread_set_name (mono_native_thread_id_get (), "SGen worker");
2355 /* Variables holding start/end nursery so it won't have to be passed at every call */
2356 static void *scan_area_arg_start, *scan_area_arg_end;
2359 mono_gc_conservatively_scan_area (void *start, void *end)
2361 sgen_conservatively_pin_objects_from ((void **)start, (void **)end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
2365 mono_gc_scan_object (void *obj, void *gc_data)
2367 ScanCopyContext *ctx = (ScanCopyContext *)gc_data;
2368 ctx->ops->copy_or_mark_object ((GCObject**)&obj, ctx->queue);
2373 * Mark from thread stacks and registers.
2376 sgen_client_scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, ScanCopyContext ctx)
2378 scan_area_arg_start = start_nursery;
2379 scan_area_arg_end = end_nursery;
2381 FOREACH_THREAD (info) {
2382 int skip_reason = 0;
2383 void *aligned_stack_start;
2385 if (info->client_info.skip) {
2386 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);
2388 } else if (info->client_info.gc_disabled) {
2389 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);
2391 } else if (!mono_thread_info_is_live (info)) {
2392 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);
2394 } else if (!info->client_info.stack_start) {
2395 SGEN_LOG (3, "Skipping starting or detaching thread %p", info);
2399 binary_protocol_scan_stack ((gpointer)mono_thread_info_get_tid (info), info->client_info.stack_start, info->client_info.stack_end, skip_reason);
2404 g_assert (info->client_info.stack_start);
2405 g_assert (info->client_info.stack_end);
2407 aligned_stack_start = (void*)(mword) ALIGN_TO ((mword)info->client_info.stack_start, SIZEOF_VOID_P);
2409 /* Windows uses a guard page before the committed stack memory pages to detect when the
2410 stack needs to be grown. If we suspend a thread just after a function prolog has
2411 decremented the stack pointer to point into the guard page but before the thread has
2412 been able to read or write to that page, starting the stack scan at aligned_stack_start
2413 will raise a STATUS_GUARD_PAGE_VIOLATION and the process will crash. This code uses
2414 VirtualQuery() to determine whether stack_start points into the guard page and then
2415 updates aligned_stack_start to point at the next non-guard page. */
2416 MEMORY_BASIC_INFORMATION mem_info;
2417 SIZE_T result = VirtualQuery(info->client_info.stack_start, &mem_info, sizeof(mem_info));
2418 g_assert (result != 0);
2419 if (mem_info.Protect & PAGE_GUARD) {
2420 aligned_stack_start = ((char*) mem_info.BaseAddress) + mem_info.RegionSize;
2424 g_assert (info->client_info.suspend_done);
2425 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 ());
2426 if (mono_gc_get_gc_callbacks ()->thread_mark_func && !conservative_stack_mark) {
2427 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);
2428 } else if (!precise) {
2429 if (!conservative_stack_mark) {
2430 fprintf (stderr, "Precise stack mark not supported - disabling.\n");
2431 conservative_stack_mark = TRUE;
2433 //FIXME we should eventually use the new stack_mark from coop
2434 sgen_conservatively_pin_objects_from ((void **)aligned_stack_start, (void **)info->client_info.stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
2438 sgen_conservatively_pin_objects_from ((void**)&info->client_info.ctx, (void**)(&info->client_info.ctx + 1),
2439 start_nursery, end_nursery, PIN_TYPE_STACK);
2442 // This is used on Coop GC for platforms where we cannot get the data for individual registers.
2443 // We force a spill of all registers into the stack and pass a chunk of data into sgen.
2444 //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
2445 MonoThreadUnwindState *state = &info->client_info.info.thread_saved_state [SELF_SUSPEND_STATE_INDEX];
2446 if (state && state->gc_stackdata) {
2447 sgen_conservatively_pin_objects_from ((void **)state->gc_stackdata, (void**)((char*)state->gc_stackdata + state->gc_stackdata_size),
2448 start_nursery, end_nursery, PIN_TYPE_STACK);
2452 if (precise && info->client_info.info.handle_stack) {
2453 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, (GcScanFunc)ctx.ops->copy_or_mark_object, ctx.queue);
2455 } FOREACH_THREAD_END
2459 * mono_gc_set_stack_end:
2461 * Set the end of the current threads stack to STACK_END. The stack space between
2462 * STACK_END and the real end of the threads stack will not be scanned during collections.
2465 mono_gc_set_stack_end (void *stack_end)
2467 SgenThreadInfo *info;
2470 info = mono_thread_info_current ();
2472 SGEN_ASSERT (0, stack_end < info->client_info.stack_end, "Can only lower stack end");
2473 info->client_info.stack_end = stack_end;
2483 mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2485 return sgen_register_root (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED, source, msg);
2489 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2491 return sgen_register_root (start, size, descr, ROOT_TYPE_WBARRIER, source, msg);
2495 mono_gc_deregister_root (char* addr)
2497 sgen_deregister_root (addr);
2506 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
2508 return pthread_create (new_thread, attr, start_routine, arg);
2517 sgen_client_total_allocated_heap_changed (size_t allocated_heap)
2519 mono_runtime_resource_check_limit (MONO_RESOURCE_GC_HEAP, allocated_heap);
2523 mono_gc_user_markers_supported (void)
2529 mono_object_is_alive (MonoObject* o)
2535 mono_gc_get_generation (MonoObject *obj)
2537 if (sgen_ptr_in_nursery (obj))
2543 mono_gc_get_gc_name (void)
2549 mono_gc_get_description (void)
2551 #ifdef HAVE_CONC_GC_AS_DEFAULT
2552 return g_strdup ("sgen (concurrent by default)");
2554 return g_strdup ("sgen");
2559 mono_gc_set_desktop_mode (void)
2564 mono_gc_is_moving (void)
2570 mono_gc_is_disabled (void)
2576 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
2583 mono_gc_max_generation (void)
2589 mono_gc_precise_stack_mark_enabled (void)
2591 return !conservative_stack_mark;
2595 mono_gc_collect (int generation)
2597 sgen_gc_collect (generation);
2601 mono_gc_collection_count (int generation)
2603 return sgen_gc_collection_count (generation);
2607 mono_gc_get_used_size (void)
2609 return (int64_t)sgen_gc_get_used_size ();
2613 mono_gc_get_heap_size (void)
2615 return (int64_t)sgen_gc_get_total_heap_allocation ();
2619 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
2621 return sgen_make_user_root_descriptor (marker);
2625 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
2627 return SGEN_DESC_STRING;
2631 mono_gc_get_nursery (int *shift_bits, size_t *size)
2633 *size = sgen_nursery_size;
2634 *shift_bits = DEFAULT_NURSERY_BITS;
2635 return sgen_get_nursery_start ();
2639 mono_gc_get_los_limit (void)
2641 return SGEN_MAX_SMALL_OBJ_SIZE;
2645 sgen_client_default_metadata (void)
2647 return mono_domain_get ();
2651 sgen_client_metadata_for_object (GCObject *obj)
2653 return mono_object_domain (obj);
2657 * mono_gchandle_is_in_domain:
2658 * @gchandle: a GCHandle's handle.
2659 * @domain: An application domain.
2661 * Returns: TRUE if the object wrapped by the @gchandle belongs to the specific @domain.
2664 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
2666 MonoDomain *gchandle_domain = (MonoDomain *)sgen_gchandle_get_metadata (gchandle);
2667 return domain->domain_id == gchandle_domain->domain_id;
2671 * mono_gchandle_free_domain:
2672 * @unloading: domain that is unloading
2674 * Function used internally to cleanup any GC handle for objects belonging
2675 * to the specified domain during appdomain unload.
2678 mono_gchandle_free_domain (MonoDomain *unloading)
2683 null_link_if_in_domain (gpointer hidden, GCHandleType handle_type, int max_generation, gpointer user)
2685 MonoDomain *unloading_domain = (MonoDomain *)user;
2686 MonoDomain *obj_domain;
2687 gboolean is_weak = MONO_GC_HANDLE_TYPE_IS_WEAK (handle_type);
2688 if (MONO_GC_HANDLE_IS_OBJECT_POINTER (hidden)) {
2689 MonoObject *obj = (MonoObject *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2690 obj_domain = mono_object_domain (obj);
2692 obj_domain = (MonoDomain *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2694 if (unloading_domain->domain_id == obj_domain->domain_id)
2700 sgen_null_links_for_domain (MonoDomain *domain)
2703 for (type = HANDLE_TYPE_MIN; type < HANDLE_TYPE_MAX; ++type)
2704 sgen_gchandle_iterate ((GCHandleType)type, GENERATION_OLD, null_link_if_in_domain, domain);
2708 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
2710 sgen_gchandle_set_target (gchandle, obj);
2714 sgen_client_gchandle_created (int handle_type, GCObject *obj, guint32 handle)
2716 #ifndef DISABLE_PERFCOUNTERS
2717 mono_perfcounters->gc_num_handles++;
2719 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handle_type, handle, obj);
2723 sgen_client_gchandle_destroyed (int handle_type, guint32 handle)
2725 #ifndef DISABLE_PERFCOUNTERS
2726 mono_perfcounters->gc_num_handles--;
2728 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handle_type, handle, NULL);
2732 sgen_client_ensure_weak_gchandles_accessible (void)
2735 * During the second bridge processing step the world is
2736 * running again. That step processes all weak links once
2737 * more to null those that refer to dead objects. Before that
2738 * is completed, those links must not be followed, so we
2739 * conservatively wait for bridge processing when any weak
2740 * link is dereferenced.
2742 /* FIXME: A GC can occur after this check fails, in which case we
2743 * should wait for bridge processing but would fail to do so.
2745 if (G_UNLIKELY (bridge_processing_in_progress))
2746 mono_gc_wait_for_bridge_processing ();
2750 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
2754 result = func (data);
2755 UNLOCK_INTERRUPTION;
2760 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
2766 mono_gc_get_card_table (int *shift_bits, gpointer *mask)
2768 return sgen_get_card_table_configuration (shift_bits, mask);
2772 mono_gc_card_table_nursery_check (void)
2774 return !sgen_get_major_collector ()->is_concurrent;
2777 /* Negative value to remove */
2779 mono_gc_add_memory_pressure (gint64 value)
2781 /* FIXME: Implement at some point? */
2789 sgen_client_degraded_allocation (size_t size)
2791 static int last_major_gc_warned = -1;
2792 static int num_degraded = 0;
2794 if (last_major_gc_warned < (int)gc_stats.major_gc_count) {
2796 if (num_degraded == 1 || num_degraded == 3)
2797 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Degraded allocation. Consider increasing nursery-size if the warning persists.");
2798 else if (num_degraded == 10)
2799 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Repeated degraded allocation. Consider increasing nursery-size.");
2800 last_major_gc_warned = gc_stats.major_gc_count;
2809 sgen_client_description_for_internal_mem_type (int type)
2812 case INTERNAL_MEM_EPHEMERON_LINK: return "ephemeron-link";
2813 case INTERNAL_MEM_MOVED_OBJECT: return "moved-object";
2820 sgen_client_pre_collection_checks (void)
2822 if (sgen_mono_xdomain_checks) {
2823 sgen_clear_nursery_fragments ();
2824 sgen_check_for_xdomain_refs ();
2829 sgen_client_vtable_is_inited (MonoVTable *vt)
2831 return vt->klass->inited;
2835 sgen_client_vtable_get_namespace (MonoVTable *vt)
2837 return vt->klass->name_space;
2841 sgen_client_vtable_get_name (MonoVTable *vt)
2843 return vt->klass->name;
2851 sgen_client_init (void)
2854 MonoThreadInfoCallbacks cb;
2856 cb.thread_register = sgen_thread_register;
2857 cb.thread_detach = sgen_thread_detach;
2858 cb.thread_unregister = sgen_thread_unregister;
2859 cb.thread_attach = sgen_thread_attach;
2860 cb.mono_thread_in_critical_region = thread_in_critical_region;
2861 cb.ip_in_critical_region = ip_in_critical_region;
2863 mono_threads_init (&cb, sizeof (SgenThreadInfo));
2865 ///* Keep this the default for now */
2866 /* Precise marking is broken on all supported targets. Disable until fixed. */
2867 conservative_stack_mark = TRUE;
2869 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
2871 mono_sgen_init_stw ();
2873 mono_tls_init_gc_keys ();
2875 mono_gc_register_thread (&dummy);
2879 sgen_client_handle_gc_param (const char *opt)
2881 if (g_str_has_prefix (opt, "stack-mark=")) {
2882 opt = strchr (opt, '=') + 1;
2883 if (!strcmp (opt, "precise")) {
2884 conservative_stack_mark = FALSE;
2885 } else if (!strcmp (opt, "conservative")) {
2886 conservative_stack_mark = TRUE;
2888 sgen_env_var_error (MONO_GC_PARAMS_NAME, conservative_stack_mark ? "Using `conservative`." : "Using `precise`.",
2889 "Invalid value `%s` for `stack-mark` option, possible values are: `precise`, `conservative`.", opt);
2891 } else if (g_str_has_prefix (opt, "bridge-implementation=")) {
2892 opt = strchr (opt, '=') + 1;
2893 sgen_set_bridge_implementation (opt);
2894 } else if (g_str_has_prefix (opt, "toggleref-test")) {
2895 /* FIXME: This should probably in MONO_GC_DEBUG */
2896 sgen_register_test_toggleref_callback ();
2897 } else if (!sgen_bridge_handle_gc_param (opt)) {
2904 sgen_client_print_gc_params_usage (void)
2906 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
2910 sgen_client_handle_gc_debug (const char *opt)
2912 if (!strcmp (opt, "xdomain-checks")) {
2913 sgen_mono_xdomain_checks = TRUE;
2914 } else if (!strcmp (opt, "do-not-finalize")) {
2915 mono_do_not_finalize = TRUE;
2916 } else if (g_str_has_prefix (opt, "do-not-finalize=")) {
2917 opt = strchr (opt, '=') + 1;
2918 mono_do_not_finalize = TRUE;
2919 mono_do_not_finalize_class_names = g_strsplit (opt, ",", 0);
2920 } else if (!strcmp (opt, "log-finalizers")) {
2921 log_finalizers = TRUE;
2922 } else if (!strcmp (opt, "no-managed-allocator")) {
2923 sgen_set_use_managed_allocator (FALSE);
2924 } else if (!sgen_bridge_handle_gc_debug (opt)) {
2931 sgen_client_print_gc_debug_usage (void)
2933 fprintf (stderr, " xdomain-checks\n");
2934 fprintf (stderr, " do-not-finalize\n");
2935 fprintf (stderr, " log-finalizers\n");
2936 fprintf (stderr, " no-managed-allocator\n");
2937 sgen_bridge_print_gc_debug_usage ();
2942 sgen_client_get_provenance (void)
2944 #ifdef SGEN_OBJECT_PROVENANCE
2945 MonoGCCallbacks *cb = mono_gc_get_gc_callbacks ();
2946 gpointer (*get_provenance_func) (void);
2949 get_provenance_func = cb->get_provenance_func;
2950 if (get_provenance_func)
2951 return get_provenance_func ();
2959 sgen_client_describe_invalid_pointer (GCObject *ptr)
2961 sgen_bridge_describe_pointer (ptr);
2964 static gboolean gc_inited;
2967 mono_gc_base_init (void)
2972 mono_counters_init ();
2975 mono_w32handle_init ();
2978 #ifdef HEAVY_STATISTICS
2979 mono_counters_register ("los marked cards", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_marked_cards);
2980 mono_counters_register ("los array cards scanned ", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_cards);
2981 mono_counters_register ("los array remsets", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_remsets);
2983 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_set_arrayref);
2984 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_value_copy);
2985 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_object_copy);
2994 mono_gc_base_cleanup (void)
2996 sgen_thread_pool_shutdown ();
2998 // We should have consumed any outstanding moves.
2999 g_assert (sgen_pointer_queue_is_empty (&moved_objects_queue));
3003 mono_gc_is_null (void)