From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 9AD5E200 for ; Tue, 5 Dec 2017 16:13:38 +0100 (CET) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Dec 2017 07:13:37 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.45,364,1508828400"; d="scan'208";a="15625552" Received: from irsmsx101.ger.corp.intel.com ([163.33.3.153]) by orsmga002.jf.intel.com with ESMTP; 05 Dec 2017 07:13:35 -0800 Received: from irsmsx111.ger.corp.intel.com (10.108.20.4) by IRSMSX101.ger.corp.intel.com (163.33.3.153) with Microsoft SMTP Server (TLS) id 14.3.319.2; Tue, 5 Dec 2017 15:13:35 +0000 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.67]) by irsmsx111.ger.corp.intel.com ([169.254.2.30]) with mapi id 14.03.0319.002; Tue, 5 Dec 2017 15:13:34 +0000 From: "Ananyev, Konstantin" To: Thomas Monjalon CC: Matan Azrad , Neil Horman , =?iso-8859-1?Q?Ga=EBtan_Rivet?= , "Wu, Jingjing" , "dev@dpdk.org" Thread-Topic: [dpdk-dev] [PATCH 2/5] ethdev: add port ownership Thread-Index: AQHTaEBN2MZq7Ar1QEOc1EFfayHFMqMs3xqAgAANj4CAAX1kAIAC4D6AgAAvRkCAADBDgIAC8rjggAAQg4CAADVh0A== Date: Tue, 5 Dec 2017 15:13:33 +0000 Message-ID: <2601191342CEEE43887BDE71AB9772585FAC4B54@irsmsx105.ger.corp.intel.com> References: <1511870281-15282-1-git-send-email-matan@mellanox.com> <2601191342CEEE43887BDE71AB9772585FAC4A12@irsmsx105.ger.corp.intel.com> <8014002.LVodVVWTJF@xps> In-Reply-To: <8014002.LVodVVWTJF@xps> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiODQwM2I5OTEtODY4My00YWY4LWEwODctZmU0MWI5YzczZjkwIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6IlwvakFSb1NLbDMwUU9EbEJMS0ZnQWpiNWV5OUpyRUltREpoZDhWMERzS0k0PSJ9 x-ctpclassification: CTP_IC dlp-product: dlpe-windows dlp-version: 11.0.0.116 dlp-reaction: no-action x-originating-ip: [163.33.239.181] Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH 2/5] ethdev: add port ownership 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: Tue, 05 Dec 2017 15:13:39 -0000 Hi Thomas, > Hi, =A0 > I will give my view on locking and synchronization in a different email. > Let's discuss about the API here. =A0 > 05/12/2017 12:12, Ananyev, Konstantin: > >> From: Matan Azrad [mailto:matan@mellanox.com] >> > From: Ananyev, Konstantin [mailto:konstantin.ananyev@intel.com] =A0 > > > > If the goal is just to have an ability to recognize is that device = is managed by > > > > another device (failsafe, bonding, etc.), then I think all we need = is a pointer > > > > to rte_eth_dev_data of the owner (NULL would mean no owner). > > >=20 > > > I think string is better than a pointer from the next reasons: > > > 1. It is more human friendly than pointers for debug and printing. > >=20 > > We can have a function that would take an owner pointer and produce nic= e > > pretty formatted text explanation: "owned by fail-safe device at port X= " or so. =A0 > I don't think it is possible or convenient to have such function. Why do you think it is not possible? > Keep in mind that the owner can be an application thread. > If you prefer using a single function pointer (may help for > atomic implementation), we can allocate an owner structure containing > a name as a string to identify the owner in human readable format. > Then we just have to set the pointer of this struct to rte_eth_dev_data. Basically you'd like to have an ability to set something different then pointer to rte_eth_dev_data as an owner, right? I think this is possible too, just not sure it will useful. =A0 > > What I meant - this api to set/get ownership should be sort of internal= to ethdev layer. > > Let say it would be used for failsafe/bonding (any other compound) devi= ce that needs > > to own/manage several low-level devices. > > So in normal situation user wouldn't need to use that API directly at a= ll. =A0 > Again, the application may use this API to declare its ownership. Could you explain that a bit: what would mean 'application declares an owne= rship on device'? Does it mean that no other application will be allowed to do any control op= on that device till application will clear its ownership? I.E. make sure that at each moment only one particular thread can modify de= vice configuration? Or would it be totally informal and second application will be free to igno= re it? If it will be the second one - I personally don't see much point in it. If it the first one - then simplest and most straightforward way would be - introduce a mutex (either per device or just per whole rte_eth_dev[]) and f= orce each control op to grab it at entrance release at exit. > And anwyway, it may be interesting from an application point of view > to be able to list every devices and their internal owners. Yes sure application is free to call 'get' to retrieve information etc. What I am saying for normal operation - application don't have to call that= API. I.E. - we don't need to change testpmd, etc. apps because that API was intr= oduced. Konstantin