Re: [PATCH 2/2] rdma/cm: allow user to specify IP to DGID mapping

Jason Gunthorpe
2009-10-25T18:50:28Z

On Sun, Oct 25, 2009 at 01:32:27PM +0200, Or Gerlitz wrote:
> Jason Gunthorpe wrote:
> >So why not have a more general, flexible approach? Isolating ACM from
> >librdmacm by using AF_IB is a good idea, it keeps them seperate and lets
> >ACM and future go where ever. I hope Sean can make it work with the
> >rdma_getddrinfo idea, that would completely seperate ACM and librdmacm

> Generally speaking, AF_IB/PS_IB sounds okay to me, even though I am not
> clear what applications are going to use it, maybe some examples please?

Again, my hope with the rdma_getaddrinfo idea is that apps using that
API get *all* the features with no additional code changes. Things
like GID addressing, ACM, etc all just exist under the
rdma_getaddrinfo API, so the apps don't care.

So, any time a *user* wants to use native IB features - APM, user path
selection, GID addressing, IB routing, etc - or users that want to
work with native IB labels for partitioning, QOS and IB routing.

> I don't agree, the only place where librdmacm goes to ACM is to resolve
> DGID and a route. This can be done with rdma_getdgidinfo &
> rdma_getrouteinfo if you like (maybe you do the implementation?), or

I would not be interested in such a poor API as a rdma_getdginfo,
rdma_getrouteinfo. Such a design ignores the hard won lessons of
IP.

Jason