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 65EDFC27C76 for ; Sat, 28 Jan 2023 12:04:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234034AbjA1MEl (ORCPT ); Sat, 28 Jan 2023 07:04:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46078 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233973AbjA1MEk (ORCPT ); Sat, 28 Jan 2023 07:04:40 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97EDE790A2 for ; Sat, 28 Jan 2023 04:04:39 -0800 (PST) From: Kurt Kanzenbach DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1674907478; 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: in-reply-to:in-reply-to:references:references; bh=5AotKWJ56DuXwWarl6aYeMKXu6k5f8gViBw8hYDWfFE=; b=gfhF3yN5Da0HKgRXW4nV3iaDaE/VGshSpsRXf4891N5MHLv6gMB6DlUl/RR1UJa52H9USU oHns8/ZY6Bbaim+ceX2poIqfdpZpbk0+TwVInNGfCkl7Z7c8YuFg2FZ80ACOhxJ/E0DfLe uXw2Lo2ejGSwBMz1TUYvb3ErbOjw/jV/VImOcNJCSznADucDW/5sg5jZ8ySH0t6d72bP4T kk8yNZVvDllilQw7YwhZ9Wkvzz0dZdG/qmTB9He4c4SuX49eY1KIt21UrtQ5UgeNct6Y9O x2gFrv8E6ft+LeI4NeRIvS1lpQ50Pcc5xigATJNHaCuceqOE/mrbMZnHXUGgNQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1674907478; 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: in-reply-to:in-reply-to:references:references; bh=5AotKWJ56DuXwWarl6aYeMKXu6k5f8gViBw8hYDWfFE=; b=LsfC95i4ttQdIMcOsHozAUH1BIngzJ/YmyM2yN3X2gg5PZ7m+J+KhwpJpMwrvSAz9KgAUl KO0MDQbLb1RakeAA== To: Vladimir Oltean , netdev@vger.kernel.org Cc: Vinicius Costa Gomes Subject: Re: [RFC PATCH net-next 05/15] net/sched: taprio: give higher priority to higher TCs in software dequeue mode In-Reply-To: <20230128010719.2182346-6-vladimir.oltean@nxp.com> References: <20230128010719.2182346-1-vladimir.oltean@nxp.com> <20230128010719.2182346-6-vladimir.oltean@nxp.com> Date: Sat, 28 Jan 2023 13:04:37 +0100 Message-ID: <87k016vp9m.fsf@kurt> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --=-=-= Content-Type: text/plain On Sat Jan 28 2023, Vladimir Oltean wrote: > Currently taprio iterates over child qdiscs in increasing order of TXQ > index, therefore giving higher xmit priority to TXQ 0 and lower to TXQ N. > > However, to the best of my understanding, we should prioritize based on > the traffic class, so we should really dequeue starting with the highest > traffic class and going down from there. We get to the TXQ using the > tc_to_txq[] netdev property. > > TXQs within the same TC have the same (strict) priority, so we should > pick from them as fairly as we can. Implement something very similar to > q->curband from multiq_dequeue(). Totally makes sense to me... > > Something tells me Vinicius won't like the way in which this patch > interacts with TXTIME_ASSIST_IS_ENABLED(q->flags) and NICs where TXQ 0 > really has higher priority than TXQ 1.... However, this change may be problematic for i210/i225/i226 NIC(s). AFAIK the Tx queue priorities for i225/i226 are configurable. Meaning the default could be adjusted to have Tx queue 4 with higher priority than 3 and so on. For i210 I don't know. Also Tx Launch Time only works for the lower queues. Hm. Thanks, Kurt --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQJHBAEBCgAxFiEEvLm/ssjDfdPf21mSwZPR8qpGc4IFAmPVD1UTHGt1cnRAbGlu dXRyb25peC5kZQAKCRDBk9HyqkZzgk/0D/0VzJyh1Qtuz+0/k/+ZEMvyINZEUzVN WHcfblOJU4GNqgZOjFvgxvZtF07cjgMG5ro0lCVOOisWfePhL//Fms5v+f31Ykdf mKm71m5h4G9XaV3/O6a1iGZZp7lp2L8RAnRfv5kHiMzZHQ8V6H3bIcNhdRW2GiZs s+nUmFwyZWGwtTX8TOLth2Sq0IeWQtUWkm3lVa1S1FCznszHvLIOCbSyvrfK4R9e zd3wmHslD7BzSfZ7+MOiG2J9vrbW9KjT6gHgmvxDXnk00MOAM1/I0IsGMKxQWm7U IYiiz9or7HtHs4iYrkzsSd+txQzMuIjSE95C+7pOvTVkSdxFKZRx/ZCvSwd0GV7d dXsIVOJtNGfSADFFh/QGC0fE7H/uU/LDAlXIXeo3IqvQW5eaRBR+GeqnYIxR0Sr6 1Nk7drLjF2B+SYZ5C0f7famtk21xcQDHWtRXJjYxjCs/V6i4onJLaalwvtSe/VXP z070+Acve1WDkFzOPCgjpbAwx7vF5zlxpeUTC8yRucCeZiyk71JW6YMcDkPRLfn7 Pt/0bmFlLI57Irr/HoUDpJbdWxJRH5f2J7sWOGC5RnR416TqaEPHLkGMh+wyRrun w52x8mLybzIE4sSMUhyrOw93I/6hVytqfBCDk27AkuCPzXvSVctuGVNwUwGT/F47 C1l1+kp0YneLLg== =VDMz -----END PGP SIGNATURE----- --=-=-=--