[openib-general] [PATCH] RMPP: add Dual-sided RMPP support

[Hal Rosenstock]

On Fri, 2006-06-30 at 23:58, Sean Hefty wrote:
> Add support for dual-sided RMPP transfers.
> 
> The implementation assumes that any RMPP request that requires a response uses
> DS RMPP.  Based on the RMPP start-up scenarios defined by the spec, this should
> be a valid assumption.  That is, there is no start-up scenario defined where
> an RMPP request is followed by a non-RMPP response.  By having this assumption,
> we avoid any API changes.
> 
> In order for a node that supports DS RMPP to communicate with one that does not,
> RMPP responses assume a new window size of 1 if a DS ACK has not been received.
> (By DS ACK, I'm referring to the ACK of the final ACK to the request.)  This
> is a slight spec deviation, but is necessary to allow communication with nodes
> that do not generate the DS ACK.  It also handles the case when a response is
> sent after the request state has been discarded.
> 
> Signed-off-by: Sean Hefty <sean.hefty at intel.com>
> ---
> This was tested by running grmpp between OpenFabric nodes running with and
> without DS RMPP support.  Additional testing is desirable before committing,
> since it affects all MADs using RMPP.

This worked for me in the various configurations I tried testing SA
MultiPathRecord (one real world consumer of DS RMPP).

-- Hal