From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <bruce.richardson@intel.com>
Received: from mga14.intel.com (mga14.intel.com [192.55.52.115])
 by dpdk.org (Postfix) with ESMTP id 782B9ADE3
 for <dev@dpdk.org>; Fri, 20 May 2016 12:37:51 +0200 (CEST)
Received: from fmsmga003.fm.intel.com ([10.253.24.29])
 by fmsmga103.fm.intel.com with ESMTP; 20 May 2016 03:37:50 -0700
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.26,339,1459839600"; d="scan'208";a="706217226"
Received: from bricha3-mobl3.ger.corp.intel.com ([10.237.221.57])
 by FMSMGA003.fm.intel.com with SMTP; 20 May 2016 03:37:47 -0700
Received: by  (sSMTP sendmail emulation); Fri, 20 May 2016 11:37:47 +0025
Date: Fri, 20 May 2016 11:37:47 +0100
From: Bruce Richardson <bruce.richardson@intel.com>
To: Thomas Monjalon <thomas.monjalon@6wind.com>
Cc: Ferruh Yigit <ferruh.yigit@intel.com>, dev@dpdk.org,
 Tetsuya Mukawa <mukawa@igel.co.jp>,
 Yuanhan Liu <yuanhan.liu@linux.intel.com>
Message-ID: <20160520103746.GA19260@bricha3-MOBL3>
References: <20160509213124.GK5641@yliu-dev.sh.intel.com>
 <38538365.t1P5Ut1YhZ@xps13> <573DE9BE.4070807@intel.com>
 <1891939.OmQDtN0y3O@xps13>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1891939.OmQDtN0y3O@xps13>
Organization: Intel Shannon Ltd.
User-Agent: Mutt/1.5.23 (2014-03-12)
Subject: Re: [dpdk-dev] [PATCH v2] vhost: add support for dynamic vhost PMD
 creation
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Fri, 20 May 2016 10:37:51 -0000

On Thu, May 19, 2016 at 06:44:44PM +0200, Thomas Monjalon wrote:
> 2016-05-19 17:28, Ferruh Yigit:
> > On 5/19/2016 9:33 AM, Thomas Monjalon wrote:
> > > 2016-05-18 18:10, Ferruh Yigit:
> > >> Add rte_eth_from_vhost() API to create vhost PMD dynamically from
> > >> applications.
> > > 
> > > How is it different from rte_eth_dev_attach() calling rte_eal_vdev_init()?
> > > 
> > 
> > When used rte_eth_dev_attach(), application also needs to do:
> > rte_eth_dev_configure()
> > rte_eth_rx_queue_setup()
> > rte_eth_tx_queue_setup()
> > rte_eth_dev_start()
> > 
> > rte_eth_from_vhost() does these internally, easier to use for applications.
> 
> This argument is not sufficient.
> We are not going to add new APIs just for wrapping others.

Why not - if there is a sufficient increase in developer usability by doing so?
Having one API that saves an app from having to call 5 other APIs looks like
something that should always be given fair consideration. There will obviously
be other factors to take into account too, like numbers and types of parameters
to the replacement call vs the sub-calls, but I don't think a blanket ban is
justified.

Regards,
/Bruce