From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 7B6CF2B91 for ; Fri, 6 Jan 2017 02:52:56 +0100 (CET) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP; 05 Jan 2017 17:52:54 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,323,1477983600"; d="scan'208";a="805669807" Received: from fmsmsx108.amr.corp.intel.com ([10.18.124.206]) by FMSMGA003.fm.intel.com with ESMTP; 05 Jan 2017 17:52:55 -0800 Received: from fmsmsx158.amr.corp.intel.com (10.18.116.75) by FMSMSX108.amr.corp.intel.com (10.18.124.206) with Microsoft SMTP Server (TLS) id 14.3.248.2; Thu, 5 Jan 2017 17:52:55 -0800 Received: from shsmsx104.ccr.corp.intel.com (10.239.4.70) by fmsmsx158.amr.corp.intel.com (10.18.116.75) with Microsoft SMTP Server (TLS) id 14.3.248.2; Thu, 5 Jan 2017 17:52:55 -0800 Received: from shsmsx103.ccr.corp.intel.com ([169.254.4.20]) by SHSMSX104.ccr.corp.intel.com ([10.239.4.70]) with mapi id 14.03.0248.002; Fri, 6 Jan 2017 09:52:54 +0800 From: "Tan, Jianfeng" To: "Yigit, Ferruh" , Stephen Hemminger CC: "dev@dpdk.org" , "david.marchand@6wind.com" Thread-Topic: [RFC] igb_uio: deprecate iomem and ioport mapping Thread-Index: AQHSA/bf/ZcZuT3Bo0mSw+jwmKNT6KD1XrwAgAQOFlCAMNSNAIABNH8A Date: Fri, 6 Jan 2017 01:52:53 +0000 Message-ID: References: <1472696197-37614-1-git-send-email-jianfeng.tan@intel.com> <20161202154706.3676195c@xeon-e3> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [RFC] igb_uio: deprecate iomem and ioport mapping X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Jan 2017 01:52:57 -0000 Hi, > -----Original Message----- > From: Yigit, Ferruh > Sent: Thursday, January 5, 2017 11:24 PM > To: Tan, Jianfeng; Stephen Hemminger > Cc: dev@dpdk.org; david.marchand@6wind.com > Subject: Re: [RFC] igb_uio: deprecate iomem and ioport mapping >=20 > On 12/5/2016 7:04 AM, Tan, Jianfeng wrote: > > Hi Stephen, > > > >> -----Original Message----- > >> From: Stephen Hemminger [mailto:stephen@networkplumber.org] > >> Sent: Saturday, December 3, 2016 7:47 AM > >> To: Tan, Jianfeng > >> Cc: dev@dpdk.org; david.marchand@6wind.com; Yigit, Ferruh > >> Subject: Re: [RFC] igb_uio: deprecate iomem and ioport mapping > >> > >> On Thu, 1 Sep 2016 02:16:37 +0000 > >> Jianfeng Tan wrote: > >> > >>> Previously in igb_uio, iomem is mapped, and both ioport and io mem > >>> are recorded into uio framework, which is duplicated and makes the > >>> code too complex. > >>> > >>> For iomem, DPDK user space code never opens or reads files under > >>> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/maps/. Instead, > >>> /sys/pci/bus/devices/xxxx:xx:xx.x/resourceY are used to map device > >>> memory. > >>> > >>> For ioport, non-x86 platforms cannot read from files under > >>> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/portio/ directly, because > >>> non-x86 platforms need to map port region for access in user space, > >>> see non-x86 version pci_uio_ioport_map(). x86 platforms can use the > >>> the same way as uio_pci_generic. > >>> > >>> This patch deprecates iomem and ioport mapping in igb_uio kernel > >>> module, and adjusts the iomem implementation in both igb_uio and > >>> uio_pci_generic: > >>> - for x86 platform, get ports info from /proc/ioports; > >>> - for non-x86 platform, map and get ports info by pci_uio_ioport_ma= p(). > >>> > >>> Note: this will affect those applications who are using files under > >>> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/maps/ and > >>> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/portio/. > >>> > >>> Signed-off-by: Jianfeng Tan > >> > >> What about people using older kernels with the new DPDK EAL and > >> vice versa? > > > > There are two things planned in this proposal: > > (1) deprecating iomem mapping in igb_uio, which is not used in DPDK cod= e > anyway. > > (2) deprecating ioport mapping in igb_uio, which has effect on ioport > mapping for x86 platforms. The way we use to make up is to leverage how > uio_pci_generic does, aka, based on /proc/ioports, and this proc file is > available at very early stage of Linux (Even before 2.6.32). > > > > So I don't see a problem there when running the new DPDK EAL on older > kernels. > > > > On the other way, running old DPDK EAL on new kernels, and using new > igb_uio, right? Oops, this should have problem. Thank you for pointing ou= t > this. So how about just removing iomem? And my motivation to clean > igb_uio like this way is to fix a problem here: > http://dpdk.org/dev/patchwork/patch/17495/. > > > >> It makes sense to make igb_uio generic for non DPDK > >> usage, so it should probably follow the other UIO drivers. > >> > > > > Then the problem would be backward compatibility. I might need to > reconsider this. >=20 > Hi Jianfeng, >=20 > Taking into account that this patch is for cleanup, and there may be > some backward compatibility issues mentioned by Stephen, would you mind > dropping this patch? I agree to drop this patch. >=20 > If you agree to drop, would you mind sending a patch to remove existing > deprecation notice? No problem, I'll do that. Thanks, Jianfeng >=20 > Thanks, > ferruh >=20 > > > > Thank you for reviewing! > > > > Thanks, > > Jianfeng > >