Example #1
0
int GC_general_register_disappearing_link(void * * link, void * obj)
{
    struct disappearing_link *curr_dl;
    size_t index;
    struct disappearing_link * new_dl;
    DCL_LOCK_STATE;
    
    if ((word)link & (ALIGNMENT-1))
    	ABORT("Bad arg to GC_general_register_disappearing_link");
#   ifdef THREADS
    	LOCK();
#   endif
    if (log_dl_table_size == -1
        || GC_dl_entries > ((word)1 << log_dl_table_size)) {
    	GC_grow_table((struct hash_chain_entry ***)(&dl_head),
    		      &log_dl_table_size);
	if (GC_print_stats) {
	    GC_log_printf("Grew dl table to %u entries\n",
	    	      (1 << log_dl_table_size));
	}
    }
    index = HASH2(link, log_dl_table_size);
    curr_dl = dl_head[index];
    for (curr_dl = dl_head[index]; curr_dl != 0; curr_dl = dl_next(curr_dl)) {
        if (curr_dl -> dl_hidden_link == HIDE_POINTER(link)) {
            curr_dl -> dl_hidden_obj = HIDE_POINTER(obj);
#	    ifdef THREADS
                UNLOCK();
#	    endif
            return(1);
        }
    }
    new_dl = (struct disappearing_link *)
    	GC_INTERNAL_MALLOC(sizeof(struct disappearing_link),NORMAL);
    if (0 == new_dl) {
#     ifdef THREADS
	UNLOCK();
#     endif
      new_dl = (struct disappearing_link *)
	      GC_oom_fn(sizeof(struct disappearing_link));
      if (0 == new_dl) {
	GC_finalization_failures++;
	return(2);
      }
      /* It's not likely we'll make it here, but ... */
#     ifdef THREADS
	LOCK();
#     endif
    }
    new_dl -> dl_hidden_obj = HIDE_POINTER(obj);
    new_dl -> dl_hidden_link = HIDE_POINTER(link);
    dl_set_next(new_dl, dl_head[index]);
    dl_head[index] = new_dl;
    GC_dl_entries++;
#   ifdef THREADS
        UNLOCK();
#   endif
    return(0);
}
Example #2
0
int GC_unregister_disappearing_link(void * * link)
{
    struct disappearing_link *curr_dl, *prev_dl;
    size_t index;
    DCL_LOCK_STATE;
    
    LOCK();
    index = HASH2(link, log_dl_table_size);
    if (((word)link & (ALIGNMENT-1))) goto out;
    prev_dl = 0; curr_dl = dl_head[index];
    while (curr_dl != 0) {
        if (curr_dl -> dl_hidden_link == HIDE_POINTER(link)) {
            if (prev_dl == 0) {
                dl_head[index] = dl_next(curr_dl);
            } else {
                dl_set_next(prev_dl, dl_next(curr_dl));
            }
            GC_dl_entries--;
            UNLOCK();
#	    ifdef DBG_HDRS_ALL
	      dl_set_next(curr_dl, 0);
#	    else
              GC_free((void *)curr_dl);
#	    endif
            return(1);
        }
        prev_dl = curr_dl;
        curr_dl = dl_next(curr_dl);
    }
out:
    UNLOCK();
    return(0);
}
Example #3
0
void
mono_gc_weak_link_add (void **link_addr, MonoObject *obj, gboolean track)
{
	/* libgc requires that we use HIDE_POINTER... */
	*link_addr = (void*)HIDE_POINTER (obj);
	GC_GENERAL_REGISTER_DISAPPEARING_LINK (link_addr, obj);
}
Example #4
0
static void
mono_gc_register_disappearing_link (MonoObject *obj, void **link, gboolean track, gboolean in_gc)
{
	if (obj)
		*link = HIDE_POINTER (obj, track);
	else
		*link = NULL;

#if 1
	if (in_gc) {
		process_dislink_stage_entry (obj, link);
	} else {
		while (!add_stage_entry (NUM_DISLINK_STAGE_ENTRIES, &next_dislink_stage_entry, dislink_stage_entries, obj, link)) {
			LOCK_GC;
			process_dislink_stage_entries ();
			UNLOCK_GC;
		}
	}
#else
	if (!in_gc)
		LOCK_GC;
	process_dislink_stage_entry (obj, link);
	if (!in_gc)
		UNLOCK_GC;
#endif
}
Example #5
0
/* and invoke finalizers.						*/
void GC_finalize(void)
{
    struct disappearing_link * curr_dl, * prev_dl, * next_dl;
    struct finalizable_object * curr_fo, * prev_fo, * next_fo;
    ptr_t real_ptr, real_link;
    size_t i;
    size_t dl_size = (log_dl_table_size == -1 ) ? 0 : (1 << log_dl_table_size);
    size_t fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
    
  /* Make disappearing links disappear */
    for (i = 0; i < dl_size; i++) {
      curr_dl = dl_head[i];
      prev_dl = 0;
      while (curr_dl != 0) {
        real_ptr = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_obj);
        real_link = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link);
        if (!GC_is_marked(real_ptr)) {
            *(word *)real_link = 0;
            next_dl = dl_next(curr_dl);
            if (prev_dl == 0) {
                dl_head[i] = next_dl;
            } else {
                dl_set_next(prev_dl, next_dl);
            }
            GC_clear_mark_bit((ptr_t)curr_dl);
            GC_dl_entries--;
            curr_dl = next_dl;
        } else {
            prev_dl = curr_dl;
            curr_dl = dl_next(curr_dl);
        }
      }
    }
  /* Mark all objects reachable via chains of 1 or more pointers	*/
  /* from finalizable objects.						*/
    GC_ASSERT(GC_mark_state == MS_NONE);
    for (i = 0; i < fo_size; i++) {
      for (curr_fo = fo_head[i]; curr_fo != 0; curr_fo = fo_next(curr_fo)) {
        GC_ASSERT(GC_size(curr_fo) >= sizeof(struct finalizable_object));
        real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
        if (!GC_is_marked(real_ptr)) {
	    GC_MARKED_FOR_FINALIZATION(real_ptr);
            GC_MARK_FO(real_ptr, curr_fo -> fo_mark_proc);
            if (GC_is_marked(real_ptr)) {
                WARN("Finalization cycle involving %lx\n", real_ptr);
            }
        }
      }
    }
  /* Enqueue for finalization all objects that are still		*/
  /* unreachable.							*/
    GC_bytes_finalized = 0;
    for (i = 0; i < fo_size; i++) {
      curr_fo = fo_head[i];
      prev_fo = 0;
      while (curr_fo != 0) {
        real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
        if (!GC_is_marked(real_ptr)) {
	    if (!GC_java_finalization) {
              GC_set_mark_bit(real_ptr);
	    }
            /* Delete from hash table */
              next_fo = fo_next(curr_fo);
              if (prev_fo == 0) {
                fo_head[i] = next_fo;
              } else {
                fo_set_next(prev_fo, next_fo);
              }
              GC_fo_entries--;
            /* Add to list of objects awaiting finalization.	*/
              fo_set_next(curr_fo, GC_finalize_now);
              GC_finalize_now = curr_fo;
              /* unhide object pointer so any future collections will	*/
              /* see it.						*/
              curr_fo -> fo_hidden_base = 
              		(word) REVEAL_POINTER(curr_fo -> fo_hidden_base);
              GC_bytes_finalized +=
                 	curr_fo -> fo_object_size
              		+ sizeof(struct finalizable_object);
	    GC_ASSERT(GC_is_marked(GC_base((ptr_t)curr_fo)));
            curr_fo = next_fo;
        } else {
            prev_fo = curr_fo;
            curr_fo = fo_next(curr_fo);
        }
      }
    }

  if (GC_java_finalization) {
    /* make sure we mark everything reachable from objects finalized
       using the no_order mark_proc */
      for (curr_fo = GC_finalize_now; 
  	 curr_fo != NULL; curr_fo = fo_next(curr_fo)) {
  	real_ptr = (ptr_t)curr_fo -> fo_hidden_base;
  	if (!GC_is_marked(real_ptr)) {
  	    if (curr_fo -> fo_mark_proc == GC_null_finalize_mark_proc) {
  	        GC_MARK_FO(real_ptr, GC_normal_finalize_mark_proc);
  	    }
	    if (curr_fo -> fo_mark_proc != GC_unreachable_finalize_mark_proc) {
		GC_set_mark_bit(real_ptr);
	    }
  	}
      }

    /* now revive finalize-when-unreachable objects reachable from
       other finalizable objects */
      if (need_unreachable_finalization) {
        curr_fo = GC_finalize_now;
        prev_fo = 0;
        while (curr_fo != 0) {
	  next_fo = fo_next(curr_fo);
	  if (curr_fo -> fo_mark_proc == GC_unreachable_finalize_mark_proc) {
	    real_ptr = (ptr_t)curr_fo -> fo_hidden_base;
	    if (!GC_is_marked(real_ptr)) {
	      GC_set_mark_bit(real_ptr);
	    } else {
	      if (prev_fo == 0)
		GC_finalize_now = next_fo;
	      else
		fo_set_next(prev_fo, next_fo);

              curr_fo -> fo_hidden_base =
              		(word) HIDE_POINTER(curr_fo -> fo_hidden_base);
              GC_bytes_finalized -=
                 	curr_fo -> fo_object_size + sizeof(struct finalizable_object);

	      i = HASH2(real_ptr, log_fo_table_size);
	      fo_set_next (curr_fo, fo_head[i]);
	      GC_fo_entries++;
	      fo_head[i] = curr_fo;
	      curr_fo = prev_fo;
	    }
	  }
	  prev_fo = curr_fo;
	  curr_fo = next_fo;
        }
      }
  }

  /* Remove dangling disappearing links. */
    for (i = 0; i < dl_size; i++) {
      curr_dl = dl_head[i];
      prev_dl = 0;
      while (curr_dl != 0) {
        real_link = GC_base((ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link));
        if (real_link != 0 && !GC_is_marked(real_link)) {
            next_dl = dl_next(curr_dl);
            if (prev_dl == 0) {
                dl_head[i] = next_dl;
            } else {
                dl_set_next(prev_dl, next_dl);
            }
            GC_clear_mark_bit((ptr_t)curr_dl);
            GC_dl_entries--;
            curr_dl = next_dl;
        } else {
            prev_dl = curr_dl;
            curr_dl = dl_next(curr_dl);
        }
      }
    }
}
Example #6
0
/* finalized when this finalizer is invoked.			*/
GC_API void GC_register_finalizer_inner(void * obj,
					GC_finalization_proc fn, void *cd,
					GC_finalization_proc *ofn, void **ocd,
					finalization_mark_proc mp)
{
    ptr_t base;
    struct finalizable_object * curr_fo, * prev_fo;
    size_t index;
    struct finalizable_object *new_fo;
    hdr *hhdr;
    DCL_LOCK_STATE;

#   ifdef THREADS
	LOCK();
#   endif
    if (log_fo_table_size == -1
        || GC_fo_entries > ((word)1 << log_fo_table_size)) {
    	GC_grow_table((struct hash_chain_entry ***)(&fo_head),
    		      &log_fo_table_size);
	if (GC_print_stats) {
	    GC_log_printf("Grew fo table to %u entries\n",
	    	          (1 << log_fo_table_size));
	}
    }
    /* in the THREADS case signals are disabled and we hold allocation	*/
    /* lock; otherwise neither is true.  Proceed carefully.		*/
    base = (ptr_t)obj;
    index = HASH2(base, log_fo_table_size);
    prev_fo = 0; curr_fo = fo_head[index];
    while (curr_fo != 0) {
        GC_ASSERT(GC_size(curr_fo) >= sizeof(struct finalizable_object));
        if (curr_fo -> fo_hidden_base == HIDE_POINTER(base)) {
            /* Interruption by a signal in the middle of this	*/
            /* should be safe.  The client may see only *ocd	*/
            /* updated, but we'll declare that to be his	*/
            /* problem.						*/
            if (ocd) *ocd = (void *) (curr_fo -> fo_client_data);
            if (ofn) *ofn = curr_fo -> fo_fn;
            /* Delete the structure for base. */
                if (prev_fo == 0) {
                  fo_head[index] = fo_next(curr_fo);
                } else {
                  fo_set_next(prev_fo, fo_next(curr_fo));
                }
            if (fn == 0) {
                GC_fo_entries--;
                  /* May not happen if we get a signal.  But a high	*/
                  /* estimate will only make the table larger than	*/
                  /* necessary.						*/
#		if !defined(THREADS) && !defined(DBG_HDRS_ALL)
                  GC_free((void *)curr_fo);
#		endif
            } else {
                curr_fo -> fo_fn = fn;
                curr_fo -> fo_client_data = (ptr_t)cd;
                curr_fo -> fo_mark_proc = mp;
		/* Reinsert it.  We deleted it first to maintain	*/
		/* consistency in the event of a signal.		*/
		if (prev_fo == 0) {
                  fo_head[index] = curr_fo;
                } else {
                  fo_set_next(prev_fo, curr_fo);
                }
            }
#	    ifdef THREADS
                UNLOCK();
#	    endif
            return;
        }
        prev_fo = curr_fo;
        curr_fo = fo_next(curr_fo);
    }
    if (ofn) *ofn = 0;
    if (ocd) *ocd = 0;
    if (fn == 0) {
#	ifdef THREADS
            UNLOCK();
#	endif
        return;
    }
    GET_HDR(base, hhdr);
    if (0 == hhdr) {
      /* We won't collect it, hence finalizer wouldn't be run. */
#     ifdef THREADS
          UNLOCK();
#     endif
      return;
    }
    new_fo = (struct finalizable_object *)
    	GC_INTERNAL_MALLOC(sizeof(struct finalizable_object),NORMAL);
    if (EXPECT(0 == new_fo, FALSE)) {
#     ifdef THREADS
	UNLOCK();
#     endif
      new_fo = (struct finalizable_object *)
	      GC_oom_fn(sizeof(struct finalizable_object));
      if (0 == new_fo) {
	GC_finalization_failures++;
	return;
      }
      /* It's not likely we'll make it here, but ... */
#     ifdef THREADS
	LOCK();
#     endif
    }
    GC_ASSERT(GC_size(new_fo) >= sizeof(struct finalizable_object));
    new_fo -> fo_hidden_base = (word)HIDE_POINTER(base);
    new_fo -> fo_fn = fn;
    new_fo -> fo_client_data = (ptr_t)cd;
    new_fo -> fo_object_size = hhdr -> hb_sz;
    new_fo -> fo_mark_proc = mp;
    fo_set_next(new_fo, fo_head[index]);
    GC_fo_entries++;
    fo_head[index] = new_fo;
#   ifdef THREADS
        UNLOCK();
#   endif
}
Example #7
0
/* LOCKING: requires that the GC lock is held */
static void
null_link_in_range (CopyOrMarkObjectFunc copy_func, char *start, char *end, int generation, gboolean before_finalization, GrayQueue *queue)
{
	DisappearingLinkHashTable *hash = get_dislink_hash_table (generation);
	DisappearingLink **disappearing_link_hash = hash->table;
	int disappearing_link_hash_size = hash->size;
	DisappearingLink *entry, *prev;
	int i;
	if (!hash->num_links)
		return;
	for (i = 0; i < disappearing_link_hash_size; ++i) {
		prev = NULL;
		for (entry = disappearing_link_hash [i]; entry;) {
			char *object;
			gboolean track = DISLINK_TRACK (entry);

			/*
			 * Tracked references are processed after
			 * finalization handling whereas standard weak
			 * references are processed before.  If an
			 * object is still not marked after finalization
			 * handling it means that it either doesn't have
			 * a finalizer or the finalizer has already run,
			 * so we must null a tracking reference.
			 */
			if (track == before_finalization) {
				prev = entry;
				entry = entry->next;
				continue;
			}

			object = DISLINK_OBJECT (entry);

			if (object >= start && object < end && !major_collector.is_object_live (object)) {
				if (object_is_fin_ready (object)) {
					void **p = entry->link;
					DisappearingLink *old;
					*p = NULL;
					/* remove from list */
					if (prev)
						prev->next = entry->next;
					else
						disappearing_link_hash [i] = entry->next;
					DEBUG (5, fprintf (gc_debug_file, "Dislink nullified at %p to GCed object %p\n", p, object));
					old = entry->next;
					mono_sgen_free_internal (entry, INTERNAL_MEM_DISLINK);
					entry = old;
					hash->num_links--;
					continue;
				} else {
					char *copy = object;
					copy_func ((void**)&copy, queue);

					/* Update pointer if it's moved.  If the object
					 * has been moved out of the nursery, we need to
					 * remove the link from the minor hash table to
					 * the major one.
					 *
					 * FIXME: what if an object is moved earlier?
					 */

					if (hash == &minor_disappearing_link_hash && !ptr_in_nursery (copy)) {
						void **link = entry->link;
						DisappearingLink *old;
						/* remove from list */
						if (prev)
							prev->next = entry->next;
						else
							disappearing_link_hash [i] = entry->next;
						old = entry->next;
						mono_sgen_free_internal (entry, INTERNAL_MEM_DISLINK);
						entry = old;
						hash->num_links--;

						g_assert (copy);
						*link = HIDE_POINTER (copy, track);
						add_or_remove_disappearing_link ((MonoObject*)copy, link, GENERATION_OLD);

						DEBUG (5, fprintf (gc_debug_file, "Upgraded dislink at %p to major because object %p moved to %p\n", link, object, copy));

						continue;
					} else {
						*entry->link = HIDE_POINTER (copy, track);
						DEBUG (5, fprintf (gc_debug_file, "Updated dislink at %p to %p\n", entry->link, DISLINK_OBJECT (entry)));
					}
				}
			}
			prev = entry;
			entry = entry->next;
		}
	}
}