On Mon, Aug 13, 2012 at 5:27 PM, Tzahi Oved <tza...@mellanox.com> wrote: > Sean – thanks for the feedback. > Reg the XRC semantics and object model:
Sean, Can you let us know your thoughts here? Or. > - XRC domain object allows many to many mappings where multiple XRC > TGT QPs and multiple XRC SRQs can be mapped to each other, thus a > notion of domain needs to be creates to define such group. With > RSS/TSS we only have many to one mapping where child QPs are mapped > directly to single parent. The RSS indirection table defines which > child QP will receive the ingress, there’s no remote mapping control > like in the XRC case where the initiator defines the destination > receive queue. > - The XRC protection domain attribute was established to allow > verification of a match between the destined XRC TGT QP and the > targeted XRC SRQ, with RSS/TSS we don’t enforce such a match. > From the above reason’s we didn’t find justification for creating yet > another new object – RSS/TSS domain. > > Reg ib_qp_init_attr and ib_qp_type, since RSS/TSS child/parent > attributes can be defined for multiple QP types (today IB_QPT_UD and > IB_QPT_RAW_PACKET), we believe it is cleaner to have another attribute > of ib_qpg_type. > > Reg ib_open_qp() and sharing the parent QP across multiple process, > currently we don’t support it, user mode API will provide RSS/TSS > parent QP creation and children in user space in the same process. > Having said that, we may add such support in future and current scheme > allows such future expansion where RSS/TSS parent QP may be defined as > shared, where in such case it will be allocated in kernel using the > open_qp semantics and may use shared protection domain to do so. > > Tzahi > > > On Tue, Jun 12, 2012 at 11:44 PM, Hefty, Sean <sean.he...@intel.com> wrote: >>> Do you have something more specific re how to actually align (say) the >>> RSS QP group into the framework used by XRC? >> >> Not really. That was more of a conceptual statement regarding the design. >> The operation, particularly on the receive side, just seems similar. >> >> I don't think we should force a fit if it doesn't, but what's missing from >> the XRC framework to support RSS? >> >> I guess more specifically, if I look at the changes to ib_verbs.h, can we >> avoid the changes to ib_qp_init_attr and ib_qp? I.e. why can't the qp_type >> indicate the type of group, or why couldn't ib_open_qp() be used? Should >> the associated QPs share some sort of common protection domain, like an >> XRCD, to provide some security on sharing the underlying QP across processes? >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-rdma" in >> the body of a message to majord...@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
