From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E52D9C3A5A2 for ; Fri, 23 Aug 2019 18:16:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B025221848 for ; Fri, 23 Aug 2019 18:16:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=netronome-com.20150623.gappssmtp.com header.i=@netronome-com.20150623.gappssmtp.com header.b="qyVGuq99" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390363AbfHWSQP (ORCPT ); Fri, 23 Aug 2019 14:16:15 -0400 Received: from mail-qk1-f194.google.com ([209.85.222.194]:36269 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388081AbfHWSQP (ORCPT ); Fri, 23 Aug 2019 14:16:15 -0400 Received: by mail-qk1-f194.google.com with SMTP id d23so8995266qko.3 for ; Fri, 23 Aug 2019 11:16:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :organization:mime-version:content-transfer-encoding; bh=pOwvP+o982g3eCm0o0emleh55/c7Om3ik93q4vjlvS4=; b=qyVGuq996Q9Q1M3/ZFkdRGomTJuORxFfJ4iw8JFCENxSlae29+P1AW5hXWLXn/X+Uf terlZkQ/g/9VAZqzENhfdtF5ZEh9OaJzOhrg1rjXHeFtMAYCLtMlu2x2EyGjMnzh2rma 4sxYwbGFI5fc4fNVeEKKbdrq5LOAGL7NdgiAQO8s9+J8ubY4ap8cVr2x02Ay++6xGSgS nfFIwFWC5DRFTeu652hfLPH3B5NmXI+P/w2p5IG4KWioo2T5LsnJoXVooAiS4amZrTPn /rTgcQ1B2s48IIyutag0AE6+ogVq46POxkFGXP35vJfROTe7bj79UpkZ7HlfksvZCoE9 nAdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:organization:mime-version:content-transfer-encoding; bh=pOwvP+o982g3eCm0o0emleh55/c7Om3ik93q4vjlvS4=; b=EI8lffuXLZ6ot2tUwVRFdHhbuUrY9UjmlFXLrw5iTbgZpYvhj5JCkhtHIiXXT3T7PK 38jZf7Hv3gjte3Sbt3phY8k+PC8DiI82QWey64bS8jaGnvT0sE8wiJcqa34Arn79KNHn Si0Pnj/dM1ZHBBxe7ZkI9YQxCcnR6X1tcj0h8xzzESkOd7JgD4NG85uDQF0a6Sh3Ofze dLCD7macbPi44r7q8i/xGf6L2IkVo4PJY+iKXtz8YliMcl5w2nrIGWMEw6WaZ+4fEABD IQlNF3G19lwUysUJcjF6ezz1nn5RaRd316uj7QZNw5Fo/YJkTbX4KMyyC6UewzJHN8TP 7Hvg== X-Gm-Message-State: APjAAAWURfnmKOkpp2wVRCZh9CKBIhQnZ47svsNCJtUZd0KzHwTQT4Pi YbHOllndW32cAAji238PhHbY8w== X-Google-Smtp-Source: APXvYqyHdhYe+DPjJOlLu2DwNVaPRY5k5IIzfW7wRseyxNRBaQVBZu74fkXp3XVQsuY8HSNxIBT6lQ== X-Received: by 2002:a37:a702:: with SMTP id q2mr5432770qke.213.1566584174215; Fri, 23 Aug 2019 11:16:14 -0700 (PDT) Received: from cakuba.netronome.com ([66.60.152.14]) by smtp.gmail.com with ESMTPSA id m38sm1947229qta.43.2019.08.23.11.16.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Aug 2019 11:16:13 -0700 (PDT) Date: Fri, 23 Aug 2019 11:16:01 -0700 From: Jakub Kicinski To: Saeed Mahameed Cc: "davem@davemloft.net" , "netdev@vger.kernel.org" , Moshe Shemesh Subject: Re: [net-next 4/8] net/mlx5e: Add device out of buffer counter Message-ID: <20190823111601.012fabf4@cakuba.netronome.com> In-Reply-To: <27f7cfa13d1b5e7717e2d75595ab453951b18a96.camel@mellanox.com> References: <20190822233514.31252-1-saeedm@mellanox.com> <20190822233514.31252-5-saeedm@mellanox.com> <20190822183324.79b74f7b@cakuba.netronome.com> <27f7cfa13d1b5e7717e2d75595ab453951b18a96.camel@mellanox.com> Organization: Netronome Systems, Ltd. MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, 23 Aug 2019 06:00:45 +0000, Saeed Mahameed wrote: > On Thu, 2019-08-22 at 18:33 -0700, Jakub Kicinski wrote: > > On Thu, 22 Aug 2019 23:35:52 +0000, Saeed Mahameed wrote: > > > From: Moshe Shemesh > > > > > > Added the following packets drop counter: > > > Device out of buffer - counts packets which were dropped due to > > > full > > > device internal receive queue. > > > This counter will be shown on ethtool as a new counter called > > > dev_out_of_buffer. > > > The counter is read from FW by command QUERY_VNIC_ENV. > > > > > > Signed-off-by: Moshe Shemesh > > > Signed-off-by: Saeed Mahameed > > > > Sounds like rx_fifo_errors, no? Doesn't rx_fifo_errors count RX > > overruns? > > No, that is port buffer you are looking for and we got that fully > covered in mlx5. this is different. > > This new counter is deep into the HW data path pipeline and it covers > very rare and complex scenarios that got only recently introduced with > swichdev mode and "some" lately added tunnels offloads that are routed > between VFs/PFs. > > Normally the HW is lossless once the packet passes port buffers into > the data plane pipeline, let's call that "fast lane", BUT for sriov > configurations with switchdev mode enabled and some special hand > crafted tc tunnel offloads that requires hairpin between VFs/PFs, the > hw might decide to send some traffic to a "service lane" which is still > fast path but unlike the "fast lane" it handles traffic through "HW > internal" receive and send queues (just like we do with hairpin) that > might drop packets. the whole thing is transparent to driver and it is > HW implementation specific. I see thanks for the explanation and sorry for the delayed response. Would it perhaps make sense to indicate the hairpin in the name? dev_out_of_buffer is quite a generic name, and there seems to be no doc, nor does the commit message explains it as well as you have..