[sgen] Some clarifying comments and rearrangements.

[mono.git] / mono / metadata / sgen-gc.c

diff --git a/mono/metadata/sgen-gc.c b/mono/metadata/sgen-gc.c
index 160557aee0d1308786003419a422eb2ddf245002..5ef89ea9cf3b215f854ae56897558ae6f901c56a 100644 (file)
--- a/mono/metadata/sgen-gc.c
+++ b/mono/metadata/sgen-gc.c
@@ -1087,18 +1087,27 @@ pin_objects_in_nursery (ScanCopyContext ctx)
        nursery_section->pin_queue_last_entry = nursery_section->pin_queue_first_entry + reduced_to;
 }
 
-
+/*
+ * This function is only ever called (via `collector_pin_object()` in `sgen-copy-object.h`)
+ * when we can't promote an object because we're out of memory.
+ */
 void
 sgen_pin_object (void *object, GrayQueue *queue)
 {
-       SGEN_PIN_OBJECT (object);
+       /*
+        * All pinned objects are assumed to have been staged, so we need to stage as well.
+        * Also, the count of staged objects shows that "late pinning" happened.
+        */
        sgen_pin_stage_ptr (object);
+
+       SGEN_PIN_OBJECT (object);
+       binary_protocol_pin (object, (gpointer)LOAD_VTABLE (object), safe_object_get_size (object));
+
        ++objects_pinned;
        if (G_UNLIKELY (do_pin_stats))
                sgen_pin_stats_register_object (object, safe_object_get_size (object));
 
        GRAY_OBJECT_ENQUEUE (queue, object, sgen_obj_get_descriptor_safe (object));
-       binary_protocol_pin (object, (gpointer)LOAD_VTABLE (object), safe_object_get_size (object));
 
 #ifdef ENABLE_DTRACE
        if (G_UNLIKELY (MONO_GC_OBJ_PINNED_ENABLED ())) {