From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f43.google.com (mail-wm0-f43.google.com [74.125.82.43]) by dpdk.org (Postfix) with ESMTP id 380BB2B9E for ; Wed, 21 Sep 2016 15:07:54 +0200 (CEST) Received: by mail-wm0-f43.google.com with SMTP id b130so91015259wmc.0 for ; Wed, 21 Sep 2016 06:07:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:user-agent:in-reply-to :references:mime-version:content-transfer-encoding; bh=u4xj6InhE8oChtrxBNPsO+PB09ABx6XEqyPJtGEFBYM=; b=XYl0hTRWKiDjUETl7gtQqIgHLxfaAmwGxTcJHRvzDiGAiy8sgFfZiCSC8IBNxDFYsg 4xtHDQAInQpJ0PB0RLVFDZWHqurGrK6yuBXau4jPATBS2AtJx/O99O8U5zP0vWudYXST FRSArClncCn8rVgEwUNN9vtsIs0wAobJG8impODOLgAdkTp28gx1bfj5DVRkkdSSR7YN ql85Tp3Rf2ApfBDrOJlELkO7JZRGcmL2W0tAj1Jf40ViUs0IiO2eC3Rl1uwR2ycMXHTO 7i59rfr4zAW9HhBgeleErtG0ncdlEqhZaRKshTThdktMCwi+ZGeN28cnHpNamfvVq5El bIng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:user-agent :in-reply-to:references:mime-version:content-transfer-encoding; bh=u4xj6InhE8oChtrxBNPsO+PB09ABx6XEqyPJtGEFBYM=; b=P+nsg8Mp5Fq4ZSWz80mmV8+TnlZNAzPy+vIPg4svnOL5NB1PSpIcPjPpA+1/6Xth5P 4fPAbp5d4SeROcJ2wLsewYDMbNX7CMkX0Vip0CqgZhDFRbtUJlCPOWJa4vLDPFp4v5r1 rYLKyngetMAmgQr3KL9Lj4Y7ChORNfLLfCeoFgJWj6L7NIwaqnd9k73+1APaOXgzO07u MJd3PVWhmgPa9Qpjl8nS7mJLUfMdTo3qe2UhzB1V8W5LXuZil2eskAS4RpeGlFKqJCbZ /fpgd6nZ/z2pJipbGVFEp/XDYshJMFCYm9z3JXebpNEbymLis9BXgbZKcxsYxcIUb4OB id1w== X-Gm-Message-State: AE9vXwONKE6s0UVD5GpwewRRf2CMVsRk9IVjLh0V6m5mIPOmg4K5XPOB1E27CVgoZDcu7imL X-Received: by 10.194.141.203 with SMTP id rq11mr33682588wjb.112.1474463273803; Wed, 21 Sep 2016 06:07:53 -0700 (PDT) Received: from xps13.localnet (guy78-3-82-239-227-177.fbx.proxad.net. [82.239.227.177]) by smtp.gmail.com with ESMTPSA id q142sm32459608wmd.4.2016.09.21.06.07.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 21 Sep 2016 06:07:52 -0700 (PDT) From: Thomas Monjalon To: Yuanhan Liu Cc: Ciara Loftus , dev@dpdk.org Date: Wed, 21 Sep 2016 15:07:51 +0200 Message-ID: <1673736.mOMazzh4h1@xps13> User-Agent: KMail/4.14.10 (Linux/4.5.4-1-ARCH; KDE/4.14.11; x86_64; ; ) In-Reply-To: <20160918082718.GF23158@yliu-dev.sh.intel.com> References: <1473774463-26966-1-git-send-email-ciara.loftus@intel.com> <2149205.E6pxXR7o4C@xps13> <20160918082718.GF23158@yliu-dev.sh.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [PATCH] net/vhost: Add function to retreive the 'vid' for a given port id X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Sep 2016 13:07:54 -0000 2016-09-18 16:27, Yuanhan Liu: > On Wed, Sep 14, 2016 at 10:35:53AM +0200, Thomas Monjalon wrote: > > 2016-09-14 15:21, Yuanhan Liu: > > > On Wed, Sep 14, 2016 at 09:10:48AM +0200, Thomas Monjalon wrote: > > > > 2016-09-14 12:43, Yuanhan Liu: > > > > > On Tue, Sep 13, 2016 at 05:10:09PM +0200, Thomas Monjalon wrote: > > > > > > 2016-09-13 14:47, Ciara Loftus: > > > > > > > In some cases when using the vHost PMD, certain vHost library functions > > > > > > > may still need to be accessed. One such example is the > > > > > > > rte_vhost_get_queue_num function which returns the number of virtqueues > > > > > > > reported by the guest - information which is not exposed by the PMD. > > > > > > > > > > > > > > This commit introduces a new rte_eth_vhost function that returns the > > > > > > > 'vid' associated with a given port id. This allows the PMD user to call > > > > > > > vHost library functions which require the 'vid' value. > > > > > > > > > > > > I think we should not add any API to the PMDs. > > > > > > > > > > In general, I agree with you. > > > > > > > > > > > Maybe you are looking for a generic API in ethdev. > > > > > > > > > > But maybe it's a bit hard to define a "right" generic API here. For this > > > > > case, the generic API I can think of could be: > > > > > > > > > > - an API to get queue num, like rte_eth_get_queue_enabled_num > > > > > I barely know NIC pmd drivers, but I doubt it's useful/meaningful for them. > > > > > > > > > > - an API to get a PMD driver private (or specific) data. > > > > > For vhost-pmd, it's vid. Again, I don't know what it could be for other nic > > > > > drivers. > > > > > > > > > > This one may be a better option here, because it expose a key field to > > > > > the application, vid, with which the application can invoke more vhost > > > > > APIs. And apparently, it's not feasible to try to define a generic API > > > > > for some (if not each) vhost APIs. > > > > > > > > There could be a similar need in other PMD. > > > > If we can get an opaque identifier of the device which is not the port id, > > > > we could call some specific functions of the driver not implemented in > > > > the generic ethdev API. > > > > > > That means you have to add/export the PMD API first. Isn't it against what > > > you are proposing -- "I think we should not add any API to the PMDs" ;) > > > > Yes you are totally right :) > > Except that in vhost case, we would not have any API in the PMD. > > But it would allow to have some specific API in other PMDs for the features > > which do not fit in a generic API. > > So, does that mean you are okay with this patch now? I mean, okay to introduce > a vhost PMD API? It means I would be in favor of introducing API in drivers for very specific features. In this case, I am not sure that retrieving an internal id is very specific. Opinions are welcome