-/*
- * sgen-copy-object.h: This is where objects are copied.
+/**
+ * \file
+ * This is where objects are copied.
*
* Copyright 2001-2003 Ximian, Inc
* Copyright 2003-2010 Novell, Inc.
* Copyright (C) 2012 Xamarin Inc
*
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License 2.0 as published by the Free Software Foundation;
+ * Licensed under the MIT license. See LICENSE file in the project root for full license information.
+ */
+
+/*
+ * Defines
+ *
+ * GCObject* copy_object_no_checks (GCObject *obj, SgenGrayQueue *queue)
+ *
+ * which allocates new space for `obj`, copies it there, forwards `obj` to its new location,
+ * and enqueues the copy into `queue`.
+ *
+ * To be defined by the includer:
+ *
+ * COLLECTOR_SERIAL_ALLOC_FOR_PROMOTION(vt, obj, objsize, has_refs)
*
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Library General Public License for more details.
+ * Allocates space for promoting object `obj`, with size `objsize`, and initizializes the
+ * vtable with `vt`. `has_refs` indicates whether the object contains references.
*
- * You should have received a copy of the GNU Library General Public
- * License 2.0 along with this library; if not, write to the Free
- * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * collector_pin_object(obj, queue)
+ *
+ * Called when no space for `obj` could be allocated. It must pin `obj` and enqueue it into
+ * `queue` for scanning.
*/
extern guint64 stat_copy_object_called_nursery;
extern guint64 stat_slots_allocated_in_vain;
/*
- * Copies an object and enqueues it if a queue is given.
- *
* This function can be used even if the vtable of obj is not valid
* anymore, which is the case in the parallel collector.
*/
static MONO_ALWAYS_INLINE void
-par_copy_object_no_checks (char *destination, GCVTable vt, void *obj, mword objsize, SgenGrayQueue *queue)
+par_copy_object_no_checks (char *destination, GCVTable vt, void *obj, mword objsize)
{
sgen_client_pre_copy_checks (destination, vt, obj, objsize);
binary_protocol_copy (obj, destination, vt, objsize);
SGEN_ASSERT (9, sgen_vtable_get_descriptor (vt), "vtable %p has no gc descriptor", vt);
sgen_client_update_copied_object (destination, vt, obj, objsize);
- obj = destination;
- if (queue) {
- SGEN_LOG (9, "Enqueuing gray object %p (%s)", obj, sgen_client_vtable_get_name (vt));
- GRAY_OBJECT_ENQUEUE (queue, (GCObject *)obj, sgen_vtable_get_descriptor (vt));
- }
}
/*
+ * Copies an object and enqueues it if a queue is given.
* This can return OBJ itself on OOM.
*/
static MONO_NEVER_INLINE GCObject *
GCVTable vt = SGEN_LOAD_VTABLE_UNCHECKED (obj);
gboolean has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
mword objsize = SGEN_ALIGN_UP (sgen_client_par_object_get_size (vt, obj));
- /* FIXME: Does this not mark the newly allocated object? */
void *destination = COLLECTOR_SERIAL_ALLOC_FOR_PROMOTION (vt, obj, objsize, has_references);
if (G_UNLIKELY (!destination)) {
return obj;
}
- if (!has_references)
- queue = NULL;
-
- par_copy_object_no_checks ((char *)destination, vt, obj, objsize, queue);
- /* FIXME: mark mod union cards if necessary */
+ par_copy_object_no_checks ((char *)destination, vt, obj, objsize);
/* set the forwarding pointer */
SGEN_FORWARD_OBJECT (obj, destination);
+ if (has_references) {
+ SGEN_LOG (9, "Enqueuing gray object %p (%s)", destination, sgen_client_vtable_get_name (vt));
+ GRAY_OBJECT_ENQUEUE_SERIAL (queue, (GCObject *)destination, sgen_vtable_get_descriptor (vt));
+ }
+
return (GCObject *)destination;
}
+
+#if defined(COPY_OR_MARK_PARALLEL)
+static MONO_NEVER_INLINE GCObject *
+copy_object_no_checks_par (GCObject *obj, SgenGrayQueue *queue)
+{
+ mword vtable_word = *(mword*)obj;
+ GCObject *destination;
+
+ destination = (GCObject*) SGEN_VTABLE_IS_FORWARDED (vtable_word);
+
+ if (!destination) {
+ GCVTable vt = (GCVTable) vtable_word;
+ GCObject *final_destination;
+ /*
+ * At this point we know vt is not tagged and we shouldn't access the vtable through obj
+ * since it could get copied at any time by another thread.
+ */
+ gboolean has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
+ mword objsize = SGEN_ALIGN_UP (sgen_client_par_object_get_size (vt, obj));
+ destination = COLLECTOR_PARALLEL_ALLOC_FOR_PROMOTION (vt, obj, objsize, has_references);
+
+ par_copy_object_no_checks ((char*)destination, vt, obj, objsize);
+
+ /* FIXME we might need a membar here so other threads see the vtable before we forward */
+
+ /* set the forwarding pointer */
+ SGEN_FORWARD_OBJECT_PAR (obj, destination, final_destination);
+
+ if (destination == final_destination) {
+ /* In a racing case, only the worker that allocated the object enqueues it */
+ if (has_references) {
+ SGEN_LOG (9, "Enqueuing gray object %p (%s)", destination, sgen_client_vtable_get_name (vt));
+ GRAY_OBJECT_ENQUEUE_PARALLEL (queue, (GCObject *)destination, sgen_vtable_get_descriptor (vt));
+ }
+ } else {
+ /*
+ * Unlikely case. Clear the allocated object so it doesn't confuse nursery
+ * card table scanning, since it can contain old invalid refs.
+ * FIXME make sure it is not a problem if another threads scans it while we clear
+ */
+ mono_gc_bzero_aligned (destination, objsize);
+ destination = final_destination;
+ }
+ }
+
+ return destination;
+}
+#endif
+
+#undef COLLECTOR_SERIAL_ALLOC_FOR_PROMOTION
+#undef COLLECTOR_PARALLEL_ALLOC_FOR_PROMOTION
+#undef collector_pin_object
+#undef COPY_OR_MARK_PARALLEL
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