From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bruce Richardson Subject: Re: [PATCH v2 10/10] pci: place all uio pci device ids in a dedicated section Date: Wed, 24 Feb 2016 11:37:19 +0000 Message-ID: <20160224113719.GA10520@bricha3-MOBL3> References: <1452430254-30390-1-git-send-email-david.marchand@6wind.com> <1453120248-28274-1-git-send-email-david.marchand@6wind.com> <1453120248-28274-11-git-send-email-david.marchand@6wind.com> <3759018.lgeOm8Q2D2@xps13> <20160119142930.GA25388@hmsreliant.think-freely.org> <20160119081019.607a9b48@xeon-e3> <20160119205614.GA24277@hmsreliant.think-freely.org> <20160119133514.03cf193f@xeon-e3> <20160120154000.GA13410@hmsreliant.think-freely.org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Cc: dev@dpdk.org, Neil Horman To: Neil Horman Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id BF6AD2BB5 for ; Wed, 24 Feb 2016 12:37:23 +0100 (CET) Content-Disposition: inline In-Reply-To: <20160120154000.GA13410@hmsreliant.think-freely.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Wed, Jan 20, 2016 at 10:40:00AM -0500, Neil Horman wrote: > On Tue, Jan 19, 2016 at 01:35:14PM -0800, Stephen Hemminger wrote: > > On Tue, 19 Jan 2016 15:56:14 -0500 > > Neil Horman wrote: > >=20 > > > On Tue, Jan 19, 2016 at 08:10:19AM -0800, Stephen Hemminger wrote: > > > > On Tue, 19 Jan 2016 09:29:31 -0500 > > > > Neil Horman wrote: > > > >=20 > > > > > On Tue, Jan 19, 2016 at 08:30:40AM +0100, Thomas Monjalon wrote= : > > > > > > 2016-01-18 13:30, David Marchand: > > > > > > > We could do something =E0 la modinfo, but let's keep it sim= ple for now. > > > > > > >=20 > > > > > > > With this, you can extract the devices that need to be boun= d to uio / vfio > > > > > > > with tools like objdump : > > > > > > >=20 > > > > > > > $ objdump -j rte_pci_id_uio -s build/lib/librte_pmd_fm10k.s= o > > > > > > >=20 > > > > > > > Contents of section rte_pci_id_uio: > > > > > > > 15760 8680a415 ffffffff 8680d015 ffffffff ...............= . > > > > > > > 15770 8680a515 ffffffff 00000000 00000000 ...............= . > > > > > >=20 > > > > > > Yes we need a modinfo-like tool. > > > > > > Currently, the UIO/VFIO binding can be done after parsing the= PCI device list. > > > > > > It is better to define the device ids locally to their driver= s but it must > > > > > > be integrated with an appropriate parsing tool at the same ti= me. > > > > > > And more importantly than any tool, the format of these ELF d= ata must be > > > > > > properly defined, documented and extensible. > > > > > >=20 > > > > > > Is there someone experimented with such format definition? > > > > > > Stephen, you were asking for this change, what is your opinio= n? > > > > > > I remember that Neil was also interested in this change: > > > > > > http://dpdk.org/ml/archives/dev/2015-January/012115.html > > > > > > Panu, Christian, this change could be related to distribution= packaging. > > > > > > Thanks for helping to move this change forward. > > > > >=20 > > > > > Yes, I would be interested in seeing this. Is the ask here tha= t someone do it? > > > > > As I recall from the last thread that you reference, I thought = David M was > > > > > interested in writing it and soliciting for ideas. If thats no= longer the case, > > > > > I can take a stab at writing it. > > > > >=20 > > > > > Neil > > > > >=20 > > > >=20 > > > > If these are libraries is there a way to have a real entry point > > > > to dump PCI id's.=20 > > > >=20 > > > Sure, you could write a method that could be dlsym-ed easily enough= to fetch an > > > array of pci ids, or just print stuff the console. Not sure thats = the best way, > > > but definately an option > > > Neil > >=20 > > It is just that reading data with objdump is a kludge likely to get b= roken. > >=20 > Not suggesting that we rely on objdump in perpituity, only that we expo= rt the > data, rather than a method to access it so that it can be reached via l= ibelf. > Using a function to return the information has implicit issues at the m= oment > (specifically if you dlopen a dpdk driver, its constructor will attempt= to > register it with the core libraries). While thats not catastrophic, it= means > more stuff than you expect gets loaded, which might have wierd side eff= ects. > Adding a separate section that you could reach via libelf would be nice= I think >=20 > Neil >=20 Hi, while there is interesting discussion on tools, are there any objections = to taking and merging this patchset as-is to at least do the cleanup of the existing pci ids list? I would assume that any tools for querying the pat= chlist can be done as additional work once this is applied.=20 Regards, /Bruce