[openib-general] OpenIB and OpenRDMA: Convergence on common RDMA APIs and ULPs for Linux

[Sean Hefty]

Roland Dreier wrote:
> I believe the way forward is to evolve the existing drivers/infiniband
> code already in Linux into a drivers/rdma that supports both IB and
> RNICs.  To be extremely blunt, I believe the RNIC-PI is irrelevant to
> the Linux kernel -- no IB vendors will support ripping out a working
> midlayer and starting from scratch, and it doesn't make sense to have
> two essentially equivalent midlayers in the same kernel.

IMO, any APIs need to evolve out of the implementation.  Trying to fit an 
implementation under an existing API tends to lead to either a poor 
implementation, or requires changes to the API anyway.

I think a useful path is for someone to implement an RNIC driver and provide 
feedback on what changes would be required of the Infiniband/core layer to 
support it.

> To put a really concrete proposal on the table, I would suggest to
> start by extending the current ib_client registration structure

Roland's proposal sounds like a reasonable and fair way to begin.  Building 
an abstraction on top of the existing layers seems secondary to adding 
support for other RDMA devices.

- Sean