[openib-general] CM private data

[Fab Tillier]

> From: Caitlin Bestler [mailto:caitlin.bestler at gmail.com]
> Sent: Thursday, May 19, 2005 9:25 AM
> 
> So being predictably unreliable for one implementation
> stage is certainly something you can get away with.
> Even when you add support it might be quite acceptable
> to send the private data *only* on the first try, or to
> require the IT-API layer to do the retries.

Only sending the user's private data on the first try requires the user to
support connection establishment with:
- no private data (no RTU received)
- zero private data (RTU retry)
- remote peer's private data (first RTU)

The receipt of private data does not mean that private data is actually what
the remote side sent, and also requires users to never use all zero private
data since that would make the second and third case above
indistinguishable.

So if the CM is going to expose the private data, it needs to put that
private data in all retries.

I'm still for hiding the RTU private data.  I think it's useless because
it's unreliable - anything exchanged via private data in the RTU must also
be exchanged by other means in case the connection is established before the
RTU is received.  Any ULPs that depend on the RTU private data are setting
themselves up for potential failures.

Just my opinion, though...

- Fab