From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] ixgbe: do not include CRC in Tx byte count Date: Fri, 10 Jul 2015 00:59:29 +0200 Message-ID: <1588256.svH7QLA2p6@xps13> References: <2601191342CEEE43887BDE71AB977258214074F6@irsmsx105.ger.corp.intel.com> <20150401113603.3591ad48@urahara> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, Stephen Hemminger To: Stephen Hemminger , "Ananyev, Konstantin" Return-path: Received: from mail-wg0-f47.google.com (mail-wg0-f47.google.com [74.125.82.47]) by dpdk.org (Postfix) with ESMTP id 159DB5955 for ; Fri, 10 Jul 2015 01:00:38 +0200 (CEST) Received: by wgck11 with SMTP id k11so235613599wgc.0 for ; Thu, 09 Jul 2015 16:00:37 -0700 (PDT) In-Reply-To: <20150401113603.3591ad48@urahara> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 2015-04-01 11:36, Stephen Hemminger: > On Wed, 1 Apr 2015 07:45:02 +0000 > Thomas Monjalon wrote: > > > 2015-03-24 23:54, Ananyev, Konstantin: > > > From: Stephen Hemminger [mailto:stephen@networkplumber.org] > > > > On Mon, 23 Mar 2015 16:45:44 +0000 > > > > "Ananyev, Konstantin" wrote: > > > > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of stephen@networkplumber.org > > > > > > From: Stephen Hemminger > > > > > > > > > > > > The ixgbe driver was including CRC in the transmit packet byte > > > > > > count, but not for packets received. > > > > > > This was notice when forwarding and > > > > > > the number of bytes received was greater than the number of bytes transmitted > > > > > > for the same number of packets. Make the driver behave like other > > > > > > virtual devices and not include CRC in byte count. Use the same queue > > > > > > counters already computed and used for Rx. > > > > > > > > > > About RX side stats - as I remember it depends to what value hw_stip_crc is set at configure(). > > > > > If hw_stip_crc==1, then, yes CRC bytes are not included into QBRC value. > > > > > I If hw_stip_crc==0, then CRC bytes are included into QBRC. > > > > > > > > That is an additional bug! > > > > * CRC should never be included in the byte count. > > > > This is not how Linux or other drivers report byte count. > > > > > > I don't have any strong opinion here... > > > For me any method (with or without CRC) of counting bytes are ok, as long as this method is identical across all PMDs we support. > > > Which makes we wonder, what approach other PMDs use? > > > > > > > > > > > * the byte count must be symmetrical Rx == Tx > > > > > > > > The Brocade router always set strip_crc to 1. So did not see the additional bug > > > > of CRC being included in byte count. > > > > > > Are you going to submit v2, to make Rx==Tx for both cases? > > > > Any conclusion? > > Without update, this patch is going to be dropped. > > I was hoping Intel would maintain their drivers and fix the issue. > Don't have resources to do it across all configurations and hardware, > my bet is that this is broken on i40e, igb, e1000 as well. Maybe that it will be properly fixed one day by someone. Current patch is dropped.