From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <zoltan.kiss@linaro.org>
Received: from mail-wi0-f174.google.com (mail-wi0-f174.google.com
 [209.85.212.174]) by dpdk.org (Postfix) with ESMTP id C5AB2C6EC
 for <dev@dpdk.org>; Fri, 31 Jul 2015 16:49:35 +0200 (CEST)
Received: by wicgj17 with SMTP id gj17so21191525wic.1
 for <dev@dpdk.org>; Fri, 31 Jul 2015 07:49:35 -0700 (PDT)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20130820;
 h=x-gm-message-state:message-id:date:from:user-agent:mime-version:to
 :subject:references:in-reply-to:content-type
 :content-transfer-encoding;
 bh=AJWdzZKgMLt6Lajd3Ru7ger6PmP00LBhD4O8VRf5xsA=;
 b=EdmpxqIr52pUpwvckl6tYwN3Zov96XEoDu6n6o/gKEsMr7eATKjR7K+bVwyr8145vK
 soV7P5CJLSy3zxwKvOZtKyxOG9q6HxT50KKGV1QFuNXFO6oNLvrS0FTvEzflM4HISlBq
 +RS+tF/TkRc2wGHTaayH5tkjmq/0B3bHl4S2la9ihaNI/Zb5oXip9pHUtYf+4VTLbCEU
 Ki5yOhAT9le1+kREPk11v1SaJhue4+Pv4DbYnJC/U6kkt5S+Gim4A7hJY8NpQdhlTdvT
 rp3eq8eWlMJRwdlwivlM2/vahFMR99OFFHpeekiTHR+4tgtPyCQHY9JQO5XfafsC9s8V
 ovVg==
X-Gm-Message-State: ALoCoQmoNyzU+dFFmOrx2j5yYvPICmIhx4CEqIZ9Lu/wBCcUDCHymPlD1IrwjBRZFD7FNv7hunWp
X-Received: by 10.194.178.1 with SMTP id cu1mr6658557wjc.59.1438354175485;
 Fri, 31 Jul 2015 07:49:35 -0700 (PDT)
Received: from [192.168.0.101] ([90.152.119.35])
 by smtp.googlemail.com with ESMTPSA id u7sm4870994wif.3.2015.07.31.07.49.34
 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
 Fri, 31 Jul 2015 07:49:34 -0700 (PDT)
Message-ID: <55BB8AFD.7010407@linaro.org>
Date: Fri, 31 Jul 2015 15:49:33 +0100
From: Zoltan Kiss <zoltan.kiss@linaro.org>
User-Agent: Mozilla/5.0 (X11; Linux x86_64;
 rv:31.0) Gecko/20100101 Thunderbird/31.8.0
MIME-Version: 1.0
To: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>, 
 "Liang, Cunming" <cunming.liang@intel.com>, "dev@dpdk.org" <dev@dpdk.org>
References: <1438330669-25942-1-git-send-email-cunming.liang@intel.com>
 <55BB47FB.3000409@linaro.org>
 <2601191342CEEE43887BDE71AB97725836A6B79C@irsmsx105.ger.corp.intel.com>
 <55BB62A3.2040906@linaro.org>
In-Reply-To: <55BB62A3.2040906@linaro.org>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: [dpdk-dev] [PATCH v1] ixgbe: remove vector pmd burst size
	restriction
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, 31 Jul 2015 14:49:36 -0000



On 31/07/15 12:57, Zoltan Kiss wrote:
>>
>> Another thing, that I just thought about:
>> Right now we invoke ixgbe_rxq_rearm() only at the start of
>> _recv_raw_pkts_vec().
>> Before it was ok, as _recv_raw_pkts_vec() would never try to read more
>> then 32 RXDs.
>> But what would happen if nb_pkts > rxq->nb_desc and rxq->rxrearm_nb == 0?
> Yes, that call would deplete the RX ring, the card wouldn't be able to
> receive more, so the receive function wouldn't be called again to rearm
> the ring.
>
Actually not, the problem is that the recv function would probably 
overran the the descriptor ring. But anyway, we should limit nb_pkts indeed.