From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Wise Subject: Re: [PATCH v2] RDMA/CMA: fix iWARP adapter TCP port space usage Date: Wed, 07 Jul 2010 09:26:14 -0700 Message-ID: <4C34AAA6.2080909@opengridcomputing.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Bernard Metzler Cc: "Tung, Chien Tin" , Jason Gunthorpe , "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "Waskiewicz Jr, Peter P" , Roland Dreier List-Id: linux-rdma@vger.kernel.org Bernard Metzler wrote: > Steve, > > merging the port space of different transports is very particular > and it would be good if we could avoid it w/o losing on transport > independence. But the IB and IW port space is _already_ merged by the RDMA_CM. That's my point. So a solution that breaks this impacts transport-independent applications that use the rdma cm... > Could we prove a strong need for that short-cut? > If its really needed, one global RDMA_CM instance should be able > to achive that requirement. But wouldn't that go together with a waste > of unused transports resources (i.e., IB binds would create > and bind also TCP sockets..?). > My comment has nothing to do with TCP ports but rather RDMA ports as abstracted by the RDMA_CM. The RDMA_PS_TCP port space is shared among all the RDMA transports. So if you rdma_bind() to port space RDMA_PS_TCP, addr INADDR_ANY, port 9999, then it will bind the cm_id to all IB and IW providers for that address/port (note the providers don't really get called until rdma_listen()). Thus if you propose moving the bind operation down into the device providers, then the IB providers will also have to add this logic. Or some solution must be defined to keep the IB and IW port spaces common. Otherwise the RDMA_CM cannot support transport independent applications... I don't think there is anything wrong with doing this, but realize this change will impact all rdma providers as well as the core. Steve. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html