Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934213AbbDVPAA (ORCPT ); Wed, 22 Apr 2015 11:00:00 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47417 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933783AbbDVO74 (ORCPT ); Wed, 22 Apr 2015 10:59:56 -0400 Message-ID: <1429714792.45956.110.camel@redhat.com> Subject: Re: [PATCH v5 00/27] IB/Verbs: IB Management Helpers From: Doug Ledford To: Liran Liss Cc: Michael Wang , Roland Dreier , Sean Hefty , Hal Rosenstock , "linux-rdma@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "hal@dev.mellanox.co.il" , Tom Tucker , Steve Wise , Hoang-Nam Nguyen , "raisch@de.ibm.com" , Mike Marciniszyn , Eli Cohen , Faisal Latif , Jack Morgenstein , Or Gerlitz , Haggai Eran , Ira Weiny , Tom Talpey , Jason Gunthorpe Date: Wed, 22 Apr 2015 10:59:52 -0400 In-Reply-To: References: <5534B8C9.506@profitbricks.com> Organization: Red Hat, Inc. Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-55hfIPu8y1J8l28xYL8Z" Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3876 Lines: 111 --=-55hfIPu8y1J8l28xYL8Z Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2015-04-21 at 23:36 +0000, Liran Liss wrote: > Hi Michael, >=20 > The spirit of this patch-set is great, but I think that we need to clarif= y some concepts. > Since this will affect the whole patch-set, I am laying out my concerns h= ere instead. >=20 > A suggestion for the resulting management helpers is given below. > I believe the result would be much more coherent. > --Liran >=20 > In general > =3D=3D=3D=3D=3D=3D=3D=3D >=20 > An ib_dev (or a port of) should be distinguished by 3 qualifiers: > - The link layer: > -- Ethernet (shared by iWARP, USNIC, and ROCE) > -- Infiniband >=20 > - The transport (*) > -- IBTA transport (shared by IB and ROCE) > -- iWARP transport > -- USNIC transport >=20 > (*) Transport means both: > - The L4 wire protocols (e.g., BTH+ headers of IBTA, optionally encapsula= ted by UDP in ROCEv2, or the iWARP stack) > - The transport semantics (for example, there are slight semantic differe= nces between IBTA and iWARP) >=20 > - The node type (**) > -- CA > -- Switch > -- Router >=20 > (**) This has been extended to also encode the transport in the current c= ode. > At least for user-space visible APIs, we might chose to leave this for ba= ckward compatibility, but we can consider cleaning up the kernel code. >=20 > So, I think that our "old-transport" below is just fine. > No need to change it (and you aren't, since it is currently implemented a= s a function). >=20 > The "new-transport" does not really exist, but is broken into several cap= ability checks of the L4 transport, optionally with conditions on the link = type. > I would remove the table below and tell what we really want to achieve: > =3D=3D> move technology-specific feature-check logic out of the (multiple= !) IB code components and various ULPs into per-feature helpers. >=20 >=20 > Detailed remarks > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D >=20 > 1) The introduction of cap_*_*() stuff should have been introduced direct= ly in patch 02/27. > This back-and-forth between rdma_ib_or_iboe() and cap_* is confusing and = increases the number of patches in the patch-set. > Do this and remove patches 16-24. >=20 > 2)The name rdma_tech_* is lame. > rdma_transport_*(), adhering to the above (*) remark, is much better. > For example, both IB and ROCE *do* use the same transport.=20 I especially want to second this. I haven't really been happy with the rdma_tech_* names at all. --=20 Doug Ledford GPG KeyID: 0E572FDD --=-55hfIPu8y1J8l28xYL8Z Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABAgAGBQJVN7doAAoJELgmozMOVy/d084P/jaY1G2WnblDIe8XYRbs/RbN gw+ivTxdIKS7Hwi1Fs6z8OZ5Kf8FgVEpqarwiLLOLHfz/tStp1fqP+DanluD8M6b hGlJVxeQOQd+6KQ2XtIilrS7/UqpwH9cltYWtPfClo5wA1r/NNIlaSwOAtZgT/xD os35/bwNLAxLfKD0doZOiAxo29Ruq54/ytl1NjGublIVNY3zZ5qGNBekjIByNoru drDA2iQFoQe2xIg4HdHkCOWyZPvDyNpx9TnM56AKcd/z+acY+M5nbQyqRdIB9lKd jZ5SALGWlD5EJl0ZhwaS3EUyIEPvej4453zEKG0h7FrLU+pPrGrwd4PuG/12xxzn EXOOkG/ukVrS8Es/6K5QUU6JXUSEjE2/WfCgtE8xHcgY0lmILG1C3rLXKkgIjcfR WuecKd2ZD1WndDtcM/LITXwmWWhjMcSeHJpazuRHcHcupv/HbUPOFulMs/75nZie hhg3S7kjJ1uAt0Q/zvngdh38i6Qhokkv7pC2PIZ+mmvFRxynOesz8ntb/ck9k/iw xKhn69bdjbeEfS/YsUAhd4p7bxfdZtapC2AkJFH+Bm+bOMdi767c4g8w/bzpiT4D ezgU+1GB4vPgOd3FW7IgKAS4IRidQmQ4o6mGdhEGhjY4dkeiWuiechGBJ3p/Zvw0 PcVnriuXhPPKZFgN+11x =Kpeu -----END PGP SIGNATURE----- --=-55hfIPu8y1J8l28xYL8Z-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/