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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2397C43334 for ; Tue, 28 Jun 2022 16:16:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245043AbiF1QQO (ORCPT ); Tue, 28 Jun 2022 12:16:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242630AbiF1QPe (ORCPT ); Tue, 28 Jun 2022 12:15:34 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 317B83915F; Tue, 28 Jun 2022 09:10:31 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 8724CB81E03; Tue, 28 Jun 2022 16:10:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2BB6C3411D; Tue, 28 Jun 2022 16:10:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656432628; bh=WpVBva7j7VZPSNBXqtv9g6t3thfqx/hVtm/7Jj0xALM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=W2lQSKlUM50c6BBCBf6d92/LNR7uq+577X3PTNJyz09slAuJZ9D0SUQ0M5sRbIdq6 ZtCRiYhDXvCQ8txOi2B9cPTzUVx+PV57FZNsZ80XhJa+8EjKJ9Yh5FyUKNxHXu+rvf tn90FuKvrpufucD2L2KFhkBT31L55d0tadC+VUuaqOACRhml8qc74aBsG94gEC7acm 5r6OOP9uFPSJo2POzRKv0cKEQDCyeh+9vMD1mAi1OO6L4y0SPbemeK9J9zFoyj0TG7 Ils1xUPbqFrgc8M0JsFyOsrmrOLMQR+uz5l/yFfLTVVlDKxEASwSoQryqkJ6oA/44+ XR6qLLnVd3UYg== Date: Tue, 28 Jun 2022 09:10:27 -0700 From: Jakub Kicinski To: Oleksij Rempel Cc: Andrew Lunn , Woojung Huh , Florian Fainelli , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "David S. Miller" , Eric Dumazet , Lukas Wunner , kernel@pengutronix.de, Paolo Abeni , Vladimir Oltean , Vivien Didelot , UNGLinuxDriver@microchip.com Subject: Re: [PATCH net-next v1 2/3] net: dsa: ar9331: add support for pause stats Message-ID: <20220628091027.3693f3f9@kernel.org> In-Reply-To: <20220628084504.GA31626@pengutronix.de> References: <20220624125902.4068436-1-o.rempel@pengutronix.de> <20220624125902.4068436-2-o.rempel@pengutronix.de> <20220624220317.ckhx6z7cmzegvoqi@skbuf> <20220626171008.GA7581@pengutronix.de> <20220627091521.3b80a4e8@kernel.org> <20220627200238.en2b5zij4sakau2t@skbuf> <20220627200959.683de11b@kernel.org> <20220628084504.GA31626@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 28 Jun 2022 10:45:04 +0200 Oleksij Rempel wrote: > After I started investigating this topic, I was really frustrated. It is > has hard to find what is wrong: my patch is not working and flow > controller is not triggered? Or every HW/driver implements counters in > some own way. Same is about byte counts: for same packet with different > NICs i have at least 3 different results: 50, 64 and 68. > It makes testing and validation a nightmare. Yeah, I was gonna mention QA in my reply. The very practical reason I've gone no-CRC, no-flow control in the driver stats in the past was that it made it possible to test the counters are correct and the match far end. I mean SW matches HW, and they both match between sender/receiver (testing NIC-switch-NIC if either link does flow control the counters on NICs won't match).