[openib-general] userspace event reporting

[Sean Hefty]

>Actually, it gets a bit messier, since the get_event call would needs an extra
>input parameter to identify which CM ID to perform the operation on.  This is a
>pretty significant semantic change since an application with many connections
>will now need to make many get_event calls, one for each CM ID it wants events
>from.  Unless the get_event operation can work asynchronously, this requires a
>thread per CM ID, which sucks.

I don't think that we'd want to add the cm_id to the get_event routine.
Get_event() could always take the reference on the cm_id before invoking the
callback.  The uCM would then be responsible for verifying that events are for
existing cm_id's, rather than the users doing the check.

Hmm... I think that this will still require some more thought.  Maybe one way to
handle this is to have destruction flush events first, then perform the actual
destroy...

- Sean