sim: Move the draining interface into a separate base class

This patch moves the draining interface from SimObject to a separate
class that can be used by any object needing draining. However,
objects not visible to the Python code (i.e., objects not deriving
from SimObject) still depend on their parents informing them when to
drain. This patch also gets rid of the CountedDrainEvent (which isn't
really an event) and replaces it with a DrainManager.

1 files changed, 7 insertions, 1 deletions

diff --git a/src/sim/serialize.hh b/src/sim/serialize.hh
index 531b2e1cd..9ee34fe80 100644
--- a/src/sim/serialize.hh
+++ b/src/sim/serialize.hh
@@ -144,8 +144,14 @@ void fromSimObject(T &t, SimObject *s)
     fromSimObject(objptr, sptr);                        \
   } while (0)
 
-/*
+/**
  * Basic support for object serialization.
+ *
+ * @note Many objects that support serialization need to be put in a
+ * consistent state when serialization takes place. We refer to the
+ * action of forcing an object into a consistent state as
+ * 'draining'. Objects that need draining inherit from Drainable. See
+ * Drainable for more information.
  */
 class Serializable
 {