[openib-general] design for communication established affiliated asynchronous event handling

[Sean Hefty]

Rimmer, Todd wrote:
> CM - have a hook so the CM can get the Async Events for all CAs.  On
> getting the Async Event for packet first packet received while in RTR
> (Communication established), the CM should treat this exactly like an
> RTU (with no private data).  The CM will need to cross reference the
> CA/QP this event was reported for to identify the applicable connection
> endpoint.  If you check the IBTA spec and the CM state machines you will
> see the CM is supposed to handle this event.  Also if the RTU does
> arrive later, the CM state machine also handles that correctly by
> discarding the RTU as if it was a duplicate.  Note: this is why
> applications should not depend on private data in the RTU.

The IB CM has this capability, and behaves as indicated.  The missing piece is 
for the RDMA CM to handle this situation.  I believe that Or's approach of 
replacing the user's QP handler with the CMA's will fix this.

> has completed its processing.  In general IB allows for this situation
> quite nicely.  The ULP can process the inbound data normally and queue
> it to the Send Q.  Putting data on a Send Q is permitted in RTR, but the

This is a good point, which indicates to me that nothing more is needed than 
handling the communication established event by the RDMA CM.

- Sean