mono/metadata/gc-internal.h

   1 /*
   2  * metadata/gc-internal.h: Internal GC interface
   3  *
   4  * Author: Paolo Molaro <lupus@ximian.com>
   5  *
   6  * (C) 2002 Ximian, Inc.
   7  * Copyright 2012 Xamarin Inc (http://www.xamarin.com)
   8  */
   9
  10 #ifndef __MONO_METADATA_GC_INTERNAL_H__
  11 #define __MONO_METADATA_GC_INTERNAL_H__
  12
  13 #include <glib.h>
  14 #include <mono/metadata/object-internals.h>
  15 #include <mono/metadata/threads-types.h>
  16 #include <mono/utils/gc_wrapper.h>
  17
  18 typedef struct {
  19         int minor_gc_count;
  20         int major_gc_count;
  21         long long minor_gc_time;
  22         long long major_gc_time;
  23         long long major_gc_time_concurrent;
  24 } GCStats;
  25
  26 #define mono_domain_finalizers_lock(domain) mono_mutex_lock (&(domain)->finalizable_objects_hash_lock);
  27 #define mono_domain_finalizers_unlock(domain) mono_mutex_unlock (&(domain)->finalizable_objects_hash_lock);
  28
  29 /* Register a memory area as a conservatively scanned GC root */
  30 #define MONO_GC_REGISTER_ROOT_PINNING(x) mono_gc_register_root ((char*)&(x), sizeof(x), NULL)
  31
  32 #define MONO_GC_UNREGISTER_ROOT(x) mono_gc_deregister_root ((char*)&(x))
  33
  34 /*
  35  * Register a memory location as a root pointing to memory allocated using
  36  * mono_gc_alloc_fixed (). This includes MonoGHashTable.
  37  */
  38 /* The result of alloc_fixed () is not GC tracked memory */
  39 #define MONO_GC_REGISTER_ROOT_FIXED(x) do { \
  40         if (!mono_gc_is_moving ())                              \
  41                 MONO_GC_REGISTER_ROOT_PINNING ((x)); \
  42         } while (0)
  43
  44 /*
  45  * Return a GC descriptor for an array containing N pointers to memory allocated
  46  * by mono_gc_alloc_fixed ().
  47  */
  48 /* For SGEN, the result of alloc_fixed () is not GC tracked memory */
  49 #define MONO_GC_ROOT_DESCR_FOR_FIXED(n) (mono_gc_is_moving () ? mono_gc_make_root_descr_all_refs (0) : NULL)
  50
  51 /* Register a memory location holding a single object reference as a GC root */
  52 #define MONO_GC_REGISTER_ROOT_SINGLE(x) do { \
  53         g_assert (sizeof (x) == sizeof (MonoObject*)); \
  54         mono_gc_register_root ((char*)&(x), sizeof(MonoObject*), mono_gc_make_root_descr_all_refs (1)); \
  55         } while (0)
  56
  57 /*
  58  * This is used for fields which point to objects which are kept alive by other references
  59  * when using Boehm.
  60  */
  61 #define MONO_GC_REGISTER_ROOT_IF_MOVING(x) do { \
  62         if (mono_gc_is_moving ()) \
  63                 MONO_GC_REGISTER_ROOT_SINGLE(x);                \
  64 } while (0)
  65
  66 #define MONO_GC_UNREGISTER_ROOT_IF_MOVING(x) do { \
  67         if (mono_gc_is_moving ()) \
  68                 MONO_GC_UNREGISTER_ROOT (x);                    \
  69 } while (0)
  70
  71 /* useful until we keep track of gc-references in corlib etc. */
  72 #define IS_GC_REFERENCE(t) (mono_gc_is_moving () ? FALSE : ((t)->type == MONO_TYPE_U && class->image == mono_defaults.corlib))
  73
  74 extern GCStats gc_stats MONO_INTERNAL;
  75
  76 void   mono_object_register_finalizer               (MonoObject  *obj) MONO_INTERNAL;
  77 void   ves_icall_System_GC_InternalCollect          (int          generation) MONO_INTERNAL;
  78 gint64 ves_icall_System_GC_GetTotalMemory           (MonoBoolean  forceCollection) MONO_INTERNAL;
  79 void   ves_icall_System_GC_KeepAlive                (MonoObject  *obj) MONO_INTERNAL;
  80 void   ves_icall_System_GC_ReRegisterForFinalize    (MonoObject  *obj) MONO_INTERNAL;
  81 void   ves_icall_System_GC_SuppressFinalize         (MonoObject  *obj) MONO_INTERNAL;
  82 void   ves_icall_System_GC_WaitForPendingFinalizers (void) MONO_INTERNAL;
  83
  84 MonoObject *ves_icall_System_GCHandle_GetTarget (guint32 handle) MONO_INTERNAL;
  85 guint32     ves_icall_System_GCHandle_GetTargetHandle (MonoObject *obj, guint32 handle, gint32 type) MONO_INTERNAL;
  86 void        ves_icall_System_GCHandle_FreeHandle (guint32 handle) MONO_INTERNAL;
  87 gpointer    ves_icall_System_GCHandle_GetAddrOfPinnedObject (guint32 handle) MONO_INTERNAL;
  88 void        ves_icall_System_GC_register_ephemeron_array (MonoObject *array) MONO_INTERNAL;
  89 MonoObject  *ves_icall_System_GC_get_ephemeron_tombstone (void) MONO_INTERNAL;
  90
  91 MonoBoolean ves_icall_Mono_Runtime_SetGCAllowSynchronousMajor (MonoBoolean flag) MONO_INTERNAL;
  92
  93 extern void mono_gc_init (void) MONO_INTERNAL;
  94 extern void mono_gc_base_init (void) MONO_INTERNAL;
  95 extern void mono_gc_cleanup (void) MONO_INTERNAL;
  96
  97 /*
  98  * Return whenever the current thread is registered with the GC (i.e. started
  99  * by the GC pthread wrappers on unix.
 100  */
 101 extern gboolean mono_gc_is_gc_thread (void) MONO_INTERNAL;
 102
 103 /*
 104  * Try to register a foreign thread with the GC, if we fail or the backend
 105  * can't cope with this concept - we return FALSE.
 106  */
 107 extern gboolean mono_gc_register_thread (void *baseptr) MONO_INTERNAL;
 108
 109 extern gboolean mono_gc_is_finalizer_internal_thread (MonoInternalThread *thread) MONO_INTERNAL;
 110
 111 extern void mono_gc_set_stack_end (void *stack_end) MONO_INTERNAL;
 112
 113 /* only valid after the RECLAIM_START GC event and before RECLAIM_END
 114  * Not exported in public headers, but can be linked to (unsupported).
 115  */
 116 extern MONO_API gboolean mono_object_is_alive (MonoObject* obj);
 117 extern MONO_API gboolean mono_gc_is_finalizer_thread (MonoThread *thread);
 118 extern MONO_API gpointer mono_gc_out_of_memory (size_t size);
 119 extern MONO_API void     mono_gc_enable_events (void);
 120
 121 /* disappearing link functionality */
 122 void        mono_gc_weak_link_add    (void **link_addr, MonoObject *obj, gboolean track) MONO_INTERNAL;
 123 void        mono_gc_weak_link_remove (void **link_addr, gboolean track) MONO_INTERNAL;
 124 MonoObject *mono_gc_weak_link_get    (void **link_addr) MONO_INTERNAL;
 125
 126 /*Ephemeron functionality. Sgen only*/
 127 gboolean    mono_gc_ephemeron_array_add (MonoObject *obj) MONO_INTERNAL;
 128
 129 /* To disable synchronous, evacuating collections - concurrent SGen only */
 130 gboolean    mono_gc_set_allow_synchronous_major (gboolean flag) MONO_INTERNAL;
 131
 132 MonoBoolean
 133 GCHandle_CheckCurrentDomain (guint32 gchandle) MONO_INTERNAL;
 134
 135 /* simple interface for data structures needed in the runtime */
 136 void* mono_gc_make_descr_from_bitmap (gsize *bitmap, int numbits) MONO_INTERNAL;
 137
 138 /* Return a root descriptor for a root with all refs */
 139 void* mono_gc_make_root_descr_all_refs (int numbits) MONO_INTERNAL;
 140
 141 /* User defined marking function */
 142 /* It should work like this:
 143  * foreach (ref in GC references in the are structure pointed to by ADDR)
 144  *    mark_func (ref)
 145  */
 146 typedef void (*MonoGCMarkFunc)     (void **addr, void *gc_data);
 147 typedef void (*MonoGCRootMarkFunc) (void *addr, MonoGCMarkFunc mark_func, void *gc_data);
 148
 149 /* Create a descriptor with a user defined marking function */
 150 MONO_API void *mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker);
 151
 152 /* Return whenever user defined marking functions are supported */
 153 gboolean mono_gc_user_markers_supported (void) MONO_INTERNAL;
 154
 155 /* desc is the result from mono_gc_make_descr*. A NULL value means
 156  * all the words might contain GC pointers.
 157  * The memory is non-moving and it will be explicitly deallocated.
 158  * size bytes will be available from the returned address (ie, descr
 159  * must not be stored in the returned memory)
 160  * NOTE: Under Boehm, this returns memory allocated using GC_malloc, so the result should
 161  * be stored into a location registered using MONO_GC_REGISTER_ROOT_FIXED ().
 162  */
 163 void* mono_gc_alloc_fixed            (size_t size, void *descr) MONO_INTERNAL;
 164 void  mono_gc_free_fixed             (void* addr) MONO_INTERNAL;
 165
 166 /* make sure the gchandle was allocated for an object in domain */
 167 gboolean mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain) MONO_INTERNAL;
 168 void     mono_gchandle_free_domain  (MonoDomain *domain) MONO_INTERNAL;
 169
 170 typedef void (*FinalizerThreadCallback) (gpointer user_data);
 171
 172 /* if there are finalizers to run, run them. Returns the number of finalizers run */
 173 gboolean mono_gc_pending_finalizers (void) MONO_INTERNAL;
 174 void     mono_gc_finalize_notify    (void) MONO_INTERNAL;
 175
 176 void* mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size) MONO_INTERNAL;
 177 void* mono_gc_alloc_obj (MonoVTable *vtable, size_t size) MONO_INTERNAL;
 178 void* mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length) MONO_INTERNAL;
 179 void* mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size) MONO_INTERNAL;
 180 void* mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len) MONO_INTERNAL;
 181 void* mono_gc_make_descr_for_string (gsize *bitmap, int numbits) MONO_INTERNAL;
 182 void* mono_gc_make_descr_for_object (gsize *bitmap, int numbits, size_t obj_size) MONO_INTERNAL;
 183 void* mono_gc_make_descr_for_array (int vector, gsize *elem_bitmap, int numbits, size_t elem_size) MONO_INTERNAL;
 184
 185 void  mono_gc_register_for_finalization (MonoObject *obj, void *user_data) MONO_INTERNAL;
 186 void  mono_gc_add_memory_pressure (gint64 value) MONO_INTERNAL;
 187 int   mono_gc_register_root (char *start, size_t size, void *descr) MONO_INTERNAL;
 188 void  mono_gc_deregister_root (char* addr) MONO_INTERNAL;
 189 int   mono_gc_finalizers_for_domain (MonoDomain *domain, MonoObject **out_array, int out_size) MONO_INTERNAL;
 190 void  mono_gc_run_finalize (void *obj, void *data) MONO_INTERNAL;
 191 void  mono_gc_clear_domain (MonoDomain * domain) MONO_INTERNAL;
 192 void* mono_gc_alloc_mature (MonoVTable *vtable) MONO_INTERNAL;
 193
 194 /*
 195  * Register a root which can only be written using a write barrier.
 196  * Writes to the root must be done using a write barrier (MONO_ROOT_SETREF).
 197  * If the root uses an user defined mark routine, the writes are not required to be
 198  * to the area between START and START+SIZE.
 199  * The write barrier allows the GC to avoid scanning this root at each collection, so it
 200  * is more efficient.
 201  * FIXME: Add an API for clearing remset entries if a root with a user defined
 202  * mark routine is deleted.
 203  */
 204 int mono_gc_register_root_wbarrier (char *start, size_t size, void *descr) MONO_INTERNAL;
 205
 206 void mono_gc_wbarrier_set_root (gpointer ptr, MonoObject *value) MONO_INTERNAL;
 207
 208 /* Set a field of a root registered using mono_gc_register_root_wbarrier () */
 209 #define MONO_ROOT_SETREF(s,fieldname,value) do {        \
 210         mono_gc_wbarrier_set_root (&((s)->fieldname), (MonoObject*)value); \
 211 } while (0)
 212
 213 void  mono_gc_finalize_threadpool_threads (void) MONO_INTERNAL;
 214
 215 /* fast allocation support */
 216
 217 /* Accessible using mono_marshal_wrapper_info_from_wrapper () */
 218 typedef struct {
 219         const char *gc_name;
 220         int alloc_type;
 221 } AllocatorWrapperInfo;
 222
 223 MonoMethod* mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box) MONO_INTERNAL;
 224 MonoMethod* mono_gc_get_managed_array_allocator (MonoClass *klass) MONO_INTERNAL;
 225 MonoMethod *mono_gc_get_managed_allocator_by_type (int atype) MONO_INTERNAL;
 226
 227 guint32 mono_gc_get_managed_allocator_types (void) MONO_INTERNAL;
 228
 229 /* Return a short string identifying the GC, indented to be saved in AOT images */
 230 const char *mono_gc_get_gc_name (void) MONO_INTERNAL;
 231
 232 /* Fast write barriers */
 233 MonoMethod* mono_gc_get_write_barrier (void) MONO_INTERNAL;
 234
 235 /* Fast valuetype copy */
 236 void mono_gc_wbarrier_value_copy_bitmap (gpointer dest, gpointer src, int size, unsigned bitmap) MONO_INTERNAL;
 237
 238 /* helper for the managed alloc support */
 239 MonoString *mono_string_alloc (int length) MONO_INTERNAL;
 240
 241 /*
 242  * Functions supplied by the runtime and called by the GC. Currently only used
 243  * by SGEN.
 244  */
 245 typedef struct {
 246         /*
 247          * Function called during thread startup/attach to allocate thread-local data
 248          * needed by the other functions.
 249          */
 250         gpointer (*thread_attach_func) (void);
 251         /*
 252          * Function called during thread deatch to free the data allocated by
 253          * thread_attach_func.
 254          */
 255         void (*thread_detach_func) (gpointer user_data);
 256         /*
 257          * Function called from every thread when suspending for GC. It can save
 258          * data needed for marking from thread stacks. user_data is the data returned
 259          * by attach_func. This might called with GC locks held and the word stopped,
 260          * so it shouldn't do any synchronization etc.
 261          */
 262         void (*thread_suspend_func) (gpointer user_data, void *sigcontext, MonoContext *ctx);
 263         /*
 264          * Function called to mark from thread stacks. user_data is the data returned
 265          * by attach_func. This is called twice, with the word stopped:
 266          * - in the first pass, it should mark areas of the stack using
 267          *   conservative marking by calling mono_gc_conservatively_scan_area ().
 268          * - in the second pass, it should mark the remaining areas of the stack
 269          *   using precise marking by calling mono_gc_scan_object ().
 270          */
 271         void (*thread_mark_func) (gpointer user_data, guint8 *stack_start, guint8 *stack_end, gboolean precise, void *gc_data);
 272 } MonoGCCallbacks;
 273
 274 /* Set the callback functions callable by the GC */
 275 void mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks) MONO_INTERNAL;
 276 MonoGCCallbacks *mono_gc_get_gc_callbacks (void) MONO_INTERNAL;
 277
 278 /* Functions callable from the thread mark func */
 279
 280 /* Scan the memory area between START and END conservatively */
 281 void mono_gc_conservatively_scan_area (void *start, void *end) MONO_INTERNAL;
 282
 283 /* Scan OBJ, returning its new address */
 284 void *mono_gc_scan_object (void *obj, void *gc_data) MONO_INTERNAL;
 285
 286 /* Return the bitmap encoded by a descriptor */
 287 gsize* mono_gc_get_bitmap_for_descr (void *descr, int *numbits) MONO_INTERNAL;
 288
 289 /* Return the suspend signal number used by the GC to suspend threads,
 290    or -1 if not applicable. */
 291 int mono_gc_get_suspend_signal (void) MONO_INTERNAL;
 292
 293 /* Return the suspend signal number used by the GC to suspend threads,
 294    or -1 if not applicable. */
 295 int mono_gc_get_restart_signal (void) MONO_INTERNAL;
 296
 297 /*
 298  * Return a human readable description of the GC in malloc-ed memory.
 299  */
 300 char* mono_gc_get_description (void) MONO_INTERNAL;
 301
 302 /*
 303  * Configure the GC to desktop mode
 304  */
 305 void mono_gc_set_desktop_mode (void) MONO_INTERNAL;
 306
 307 /*
 308  * Return whenever this GC can move objects
 309  */
 310 gboolean mono_gc_is_moving (void) MONO_INTERNAL;
 311
 312 typedef void* (*MonoGCLockedCallbackFunc) (void *data);
 313
 314 void* mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data) MONO_INTERNAL;
 315
 316 int mono_gc_get_los_limit (void) MONO_INTERNAL;
 317
 318 guint8* mono_gc_get_card_table (int *shift_bits, gpointer *card_mask) MONO_INTERNAL;
 319 gboolean mono_gc_card_table_nursery_check (void) MONO_INTERNAL;
 320
 321 void* mono_gc_get_nursery (int *shift_bits, size_t *size) MONO_INTERNAL;
 322
 323 void mono_gc_set_current_thread_appdomain (MonoDomain *domain) MONO_INTERNAL;
 324
 325 void mono_gc_set_skip_thread (gboolean skip) MONO_INTERNAL;
 326
 327 /*
 328  * Return whenever GC is disabled
 329  */
 330 gboolean mono_gc_is_disabled (void) MONO_INTERNAL;
 331
 332 #if defined(__MACH__)
 333 void mono_gc_register_mach_exception_thread (pthread_t thread) MONO_INTERNAL;
 334 pthread_t mono_gc_get_mach_exception_thread (void) MONO_INTERNAL;
 335 #endif
 336
 337 gboolean mono_gc_parse_environment_string_extract_number (const char *str, size_t *out) MONO_INTERNAL;
 338
 339 gboolean mono_gc_precise_stack_mark_enabled (void) MONO_INTERNAL;
 340
 341 FILE *mono_gc_get_logfile (void) MONO_INTERNAL;
 342
 343 typedef struct _RefQueueEntry RefQueueEntry;
 344
 345 struct _RefQueueEntry {
 346         void *dis_link;
 347         guint32 gchandle;
 348         MonoDomain *domain;
 349         void *user_data;
 350         RefQueueEntry *next;
 351 };
 352
 353 struct _MonoReferenceQueue {
 354         RefQueueEntry *queue;
 355         mono_reference_queue_callback callback;
 356         MonoReferenceQueue *next;
 357         gboolean should_be_deleted;
 358 };
 359
 360 enum {
 361         MONO_GC_FINALIZER_EXTENSION_VERSION = 1,
 362 };
 363
 364 typedef struct {
 365         int version;
 366         gboolean (*is_class_finalization_aware) (MonoClass *klass);
 367         void (*object_queued_for_finalization) (MonoObject *object);
 368 } MonoGCFinalizerCallbacks;
 369
 370 void mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks);
 371
 372
 373 #ifdef HOST_WIN32
 374 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved) MONO_INTERNAL;
 375 #endif
 376
 377 /*
 378 Those functions must be used when it's possible that either destination is not
 379 word aligned or size is not a multiple of word size.
 380 */
 381 void mono_gc_bzero_atomic (void *dest, size_t size) MONO_INTERNAL;
 382 void mono_gc_bzero_aligned (void *dest, size_t size) MONO_INTERNAL;
 383 void mono_gc_memmove_atomic (void *dest, const void *src, size_t size) MONO_INTERNAL;
 384 void mono_gc_memmove_aligned (void *dest, const void *src, size_t size) MONO_INTERNAL;
 385
 386 guint mono_gc_get_vtable_bits (MonoClass *klass) MONO_INTERNAL;
 387
 388 void mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size) MONO_INTERNAL;
 389
 390 #endif /* __MONO_METADATA_GC_INTERNAL_H__ */
 391