mono/metadata/gc-internals.h

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