From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <cyril.cressent@intel.com>
Received: from mga03.intel.com (mga03.intel.com [143.182.124.21])
 by dpdk.org (Postfix) with ESMTP id 794B658E9
 for <dev@dpdk.org>; Tue,  5 Nov 2013 11:33:02 +0100 (CET)
Received: from fmsmga001.fm.intel.com ([10.253.24.23])
 by azsmga101.ch.intel.com with ESMTP; 05 Nov 2013 02:33:54 -0800
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="4.93,639,1378882800"; d="scan'208";a="422465478"
Received: from cccressen-mobl4.ger.corp.intel.com (HELO debian)
 ([10.237.220.107])
 by fmsmga001.fm.intel.com with ESMTP; 05 Nov 2013 02:33:29 -0800
Date: Tue, 5 Nov 2013 10:33:25 +0000
From: Cyril Cressent <cyril.cressent@intel.com>
To: Jose Gavine Cueto <pepedocs@gmail.com>
Message-ID: <20131105103325.GA25808@debian>
Mail-Followup-To: Jose Gavine Cueto <pepedocs@gmail.com>,
 "dev@dpdk.org" <dev@dpdk.org>
References: <CAJ5bv6EVB-oQuVqghaPq+6UQjkiLbhy6x3ascsYZhT_14bBYRg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAJ5bv6EVB-oQuVqghaPq+6UQjkiLbhy6x3ascsYZhT_14bBYRg@mail.gmail.com>
Organization: Intel Shannon, Dromore House, East Park, Shannon, Ireland
User-Agent: Mutt/1.5.21 (2010-09-15)
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] preallocation of void ** obj_p of rte_ring_dequeue
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: Tue, 05 Nov 2013 10:33:03 -0000

On Tue, Nov 05, 2013 at 06:15:01PM +0800, Jose Gavine Cueto wrote:
> 
> When using *static int rte_ring_dequeue( structe rte_ring * r, void **
> obj_p )*, is the user presumed to allocate obj_p , or does this method
> allocates this obj_p ?

This method doesn't allocate anything ; you have to allocate the object
you want to fill yourself.

You can find more details about how to work with rings there:

- DPDK Programmer's Guide (Chapter 5 - Ring Library)
- DPDK API Documentation for rte_ring.h

Both of which are accessible at http://dpdk.org/doc

Quite a few sample applications (examples/ directory in the DPDK
distribution) also make use of rings, notably the quota_watermark one,
so it's also a good place to look at.

On a side note, it looks like the API reference page for rte_ring.h is
broken? It's missing a lot of functions. I'll look into it if I get a
chance.
http://dpdk.org/doc/api/rte__ring_8h.html#func-members

Cyril