> From: Jason Gunthorpe [mailto:jgunthorpe@xxxxxxxxxxxxxxxxxxxx] > Sent: Thursday, June 11, 2015 2:52 PM > To: Wan, Kaike > Cc: linux-rdma@xxxxxxxxxxxxxxx; Fleck, John; Weiny, Ira > Subject: Re: [PATCH v5 1/4] IB/netlink: Add defines for local service requests > through netlink > > On Thu, Jun 11, 2015 at 06:32:44PM +0000, Wan, Kaike wrote: > > > From: Jason Gunthorpe [mailto:jgunthorpe@xxxxxxxxxxxxxxxxxxxx] > > > Sent: Thursday, June 11, 2015 1:58 PM > > > To: Wan, Kaike > > > Cc: linux-rdma@xxxxxxxxxxxxxxx; Fleck, John; Weiny, Ira > > > Subject: Re: [PATCH v5 1/4] IB/netlink: Add defines for local > > > service requests through netlink > > > > > > On Thu, Jun 11, 2015 at 01:03:42PM -0400, kaike.wan@xxxxxxxxx wrote: > > > > From: Kaike Wan <kaike.wan@xxxxxxxxx> > > > > > > > > This patch adds netlink defines for SA client, local service > > > > group, local service operations, and related attributes. > > > + LS_NLA_TYPE_REVERSIBLE, > > + LS_NLA_TYPE_NUMB_PATH, > > These need to be combined. It does not make sense to request numb_paths > when the API we have is designed to return APM data. > > Recommend a 'QP Type' with options of: > - RC QP: Return up to the full 6 path tuple with full APM data > - UD QP: Return a single non-reversible path > - GMP QP: Return up to two reversible GMP paths. > > If it is hard to get accurate information then you can sketch this in and infer > RC QP and GMP QP by the request having the reversible set bit. But ideally > RDMA CM and SRP would request RC QP, IPoIB would request UD QP. It's quite indirect here for this implementation. (ib_sa_path_rec_get()) Caller reversible numb_path QP Type -------------------------------------------------------------------------- cma 1 1 GMP ipoib Not set 1 (?) UD srp Not set 1 UD In addition, on the user side, we need to convert QP type back into reversible_numpath again, which may not interpret the original request correctly. Why should we do all the translation? Is QP type definition already exported to user space? I see IBV_QPT_RC/UC/UD/RAW_PACKET/XRC_SEND/XRC_RECV, but not GMP in verbs.h. > > > +/* Local Service ServiceID attribute */ struct rdma_nla_ls_service_id > > +{ > > + __be64 service_id; > > +}; > > Do not expose BE to userspace, everything should be in cpu order. If we use cpu order, we need to do two conversions: from BE to cpu order in kernel and from cpu order to BE in user space. Struct ib_user_path_rec contains many __be32 fields. > > Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
