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 CBCA4C433EF for ; Mon, 25 Apr 2022 13:37:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236688AbiDYNki (ORCPT ); Mon, 25 Apr 2022 09:40:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229658AbiDYNkd (ORCPT ); Mon, 25 Apr 2022 09:40:33 -0400 Received: from relay10.mail.gandi.net (relay10.mail.gandi.net [IPv6:2001:4b98:dc4:8::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 186CD2AE0B for ; Mon, 25 Apr 2022 06:37:27 -0700 (PDT) Received: (Authenticated sender: maxime.chevallier@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 68C18240013; Mon, 25 Apr 2022 13:37:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1650893846; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=18zNJHD3IAD9QeHWgDT3mu9Gjegdi3D3qLCte3J/LE8=; b=dAfgSCzQaFJvf2OwvO+BiMcf1nNIJUNuxwPMb5mmalloIjqyLgGdlljQFtbUmTXQf1MbDo wAtn/EoxUMTb/+T/cEbZXpyHWw5opusv3zCnVk2vg5RX17y42TakFUhUvTA4OhBPI68Qj/ uxYoGxfqZ/d+M/VL5cmjCvOTisY/HShTJ66z8i2+63rSNVId34cbxVk5TxuCWAt6ovV1rU U/y0HdidkvHCBEXRGoKcUPEnYyYCzDP5okG1FcxkUaeVcqPPdWudQMywXpA7sDjK5JHnbf bFDb/NjrmFYLdZc0utV8YjEBwSrjbDl1HzaYBDTVy10jLWgOtvk15QPbp+R9uQ== Date: Mon, 25 Apr 2022 15:37:24 +0200 From: Maxime Chevallier To: Vladimir Oltean Cc: "netdev@vger.kernel.org" , Jakub Kicinski , Vinicius Costa Gomes , Thomas Petazzoni , "Allan.Nielsen@microchip.com" Subject: Re: Offloading Priority Tables for queue classification Message-ID: <20220425153724.17988365@pc-20.home> In-Reply-To: <20220415154229.pmzgkgvlau5mftkp@skbuf> References: <20220415173718.494f5fdb@fedora> <20220415154229.pmzgkgvlau5mftkp@skbuf> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Vladimir ! On Fri, 15 Apr 2022 15:42:29 +0000 Vladimir Oltean wrote: > Hi Maxime! > > On Fri, Apr 15, 2022 at 05:37:18PM +0200, Maxime Chevallier wrote: > > So in the end, my question would be : Is it OK to mix all of these > > together ? Using the dcb layer to configure the internal mapping of > > traffic -> priority, then using mqprio to configure the priority -> > > queue mapping, and then either TC again or ethtool do configure the > > behaviour of the queues themselves ? Or is there some other way that > > we've missed ? > > I think it's ok to mix all of those together. At least the > ocelot/felix DSA switches do support both advance QoS classification > using tc-flower > + skbedit priority action, and basic QoS classification (port-based or > IP DSCP based) using the dcbnl application table. In short, at the end > of the QoS classification process, a traffic class for the packet is > selected. Then, the frame preemption would operate on the packet's > traffic class. Thank you very much for that answer, it helps a lot. TBH when digging into classification, especially with TC, it's a bit overwhelming and it gets difficult pretty quickly to get what's the right approach. > Do you have any particular concerns? My concerns were mainly about not reinventing the wheel, but also making sure that I have the correct understanding on these classification steps. I'll make sure to CC you when I have a first series implementing that. Best regards, Maxime