[openib-general] posting send requests in RTR

[Sean Hefty]

>Not necessarily. CMA consumer at this point is a rare beast, but since the
>issue
>is not specific to CMA, let's look at some IB protocols: IPoIB connected mode
>can simply drop a packet.  So can SRP.  SDP (potential CMA consumer!) simply
>never needs to send any application data before communication established
>event.
>
>Possibly some ULPs may need an extra queue - so let them handle the complexity.

If the ULP isn't sharing a CQ across multiple QPs, it could just wait to arm the
CQ (followed by a poll) after receiving the connection establish event.  I think
the shared CQ case is the more difficult one for the ULP to handle, and I don't
know how many ULPs this affects.

If you wanted to allow queuing sends in RTR, could this be done entirely in
software under verbs?  The difficulty comes if an error occurs while trying to
post the sends once the QP transitions to RTS.

- Sean