From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from rcdn-iport-3.cisco.com (rcdn-iport-3.cisco.com [173.37.86.74]) by dpdk.org (Postfix) with ESMTP id 1E81C5F0F for ; Sat, 10 Mar 2018 01:37:49 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=1364; q=dns/txt; s=iport; t=1520642270; x=1521851870; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=Nho8gbaNv/eMzIOKSBJunxVWI+5mrufTzdMZqoWtr04=; b=JR1idDqIpbkv+xgLCcwRatHjyIGuRoo/Nf80z2Q1yJi33+dMBKlu1J1E pGmjwtnVe6RAYo8WzkxZCGYEH7QA0WVyrKQyn1dQyJpr+PRsRhMUImJVv wGYl/dfq3ycIJDflTrbjyv6mhO4Z3jsvO7iTCrsdXHK9oYyqdOvVtO7XH 4=; X-IronPort-AV: E=Sophos;i="5.47,448,1515456000"; d="scan'208";a="355318299" Received: from alln-core-6.cisco.com ([173.36.13.139]) by rcdn-iport-3.cisco.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Mar 2018 00:37:49 +0000 Received: from HYONKIM-FTCPE.cisco.com ([10.24.40.60]) by alln-core-6.cisco.com (8.14.5/8.14.5) with ESMTP id w2A0bj2A009890 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sat, 10 Mar 2018 00:37:47 GMT Date: Sat, 10 Mar 2018 09:37:44 +0900 From: Hyong Youb Kim To: Ferruh Yigit Cc: "Ananyev, Konstantin" , John Daley , "dev@dpdk.org" Message-ID: <20180310003743.GA18664@HYONKIM-FTCPE.cisco.com> References: <20180306014634.28398-2-johndale@cisco.com> <20180308024702.25974-1-johndale@cisco.com> <20180308024702.25974-4-johndale@cisco.com> <2601191342CEEE43887BDE71AB97725890F22461@irsmsx105.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.1 (2017-09-22) Subject: Re: [dpdk-dev] [PATCH v3 03/10] net/enic: heed the requested max Rx packet size 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: Sat, 10 Mar 2018 00:37:50 -0000 On Fri, Mar 09, 2018 at 03:57:46PM +0000, Ferruh Yigit wrote: > On 3/9/2018 3:51 PM, Ananyev, Konstantin wrote: [...] > >> Is this work based on an application that uses max_rx_pkt_len and to make PMD > >> compatible with that application? If so we can continue with patch, but if the > >> patch is to implement DPDK properly I suggest postponing this until > >> max_rx_pkt_len clarified. > >> > >> [1] > >> https://dpdk.org/ml/archives/dev/2018-March/092178.html > > > > I think there are quite a lot apps these days that might rely on setting MTU via > > rxmode.max_rx_pkt_len. > > I think we need to support them till we (ever) deprecate rxmode.max_rx_pkt_len. > > Right. I was trying to save effort in case something changes related > max_rx_pkt_len, but since it is not clear yet, will continue with this patch. > > > Konstantin > > testpmd has a command to change max_rx_pkt_len, a few DTS test cases rely on this feature to see if packets of certain sizes get dropped, and so on. We worked on this patch to support these cases. I prefer using only MTU, to follow the convention of most (all?) OSes. Though, this feature (max_rx_pkt_len) seems to come straight from an Intel 82599 feature. In its datasheet, see "8.2.3.22.13 Max Frame Size -- MAXFRS". Like to understand use cases for that, if anyone can share. -Hyong