From patchwork Tue Jan 19 00:40:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vinicius Costa Gomes X-Patchwork-Id: 12028471 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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_GIT autolearn=ham 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 03756C433E0 for ; Tue, 19 Jan 2021 00:41:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD1BD2225C for ; Tue, 19 Jan 2021 00:41:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732300AbhASAld (ORCPT ); Mon, 18 Jan 2021 19:41:33 -0500 Received: from mga09.intel.com ([134.134.136.24]:38525 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729933AbhASAlb (ORCPT ); Mon, 18 Jan 2021 19:41:31 -0500 IronPort-SDR: TCY2drA7nZnknuPdbURapQsxaixsleyiejOZKUkt9vFpYLrZm2mkGY2I3Bothw9fqQWWfSO+4z yJOAnMMZEZjA== X-IronPort-AV: E=McAfee;i="6000,8403,9868"; a="179011251" X-IronPort-AV: E=Sophos;i="5.79,357,1602572400"; d="scan'208";a="179011251" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jan 2021 16:40:49 -0800 IronPort-SDR: 4hawrQJj2fpyw45PFJX567hqDcoEqwoOCDKSLDlraM+SazFR400XCZ1JL8NDwYvnev65Xcc4Fp ToV0+ulebJCA== X-IronPort-AV: E=Sophos;i="5.79,357,1602572400"; d="scan'208";a="426285752" Received: from cemillan-mobl.amr.corp.intel.com (HELO localhost.localdomain) ([10.212.57.184]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jan 2021 16:40:48 -0800 From: Vinicius Costa Gomes To: netdev@vger.kernel.org Cc: Vinicius Costa Gomes , jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, kuba@kernel.org, m-karicheri2@ti.com, vladimir.oltean@nxp.com, Jose.Abreu@synopsys.com, po.liu@nxp.com, intel-wired-lan@lists.osuosl.org, anthony.l.nguyen@intel.com, mkubecek@suse.cz Subject: [PATCH net-next v2 0/8] ethtool: Add support for frame preemption Date: Mon, 18 Jan 2021 16:40:20 -0800 Message-Id: <20210119004028.2809425-1-vinicius.gomes@intel.com> X-Mailer: git-send-email 2.30.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Changes from v1: - The minimum fragment size configuration was changed to be configured in bytes to be more future proof, in case the standard changes this (the previous definition was '(X + 1) * 64', X being [0..3]) (Michal Kubecek); - In taprio, frame preemption is now configured by traffic classes (was done by queues) (Jakub Kicinski, Vladimir Oltean); - Various netlink protocol validation improvements (Jakub Kicinski); - Dropped the IGC register dump for frame preemption registers, until a stardandized way of exposing that is agreed (Jakub Kicinski); Changes from RFC v2: - Reorganised the offload enabling/disabling on the driver size; - Added a few igc fixes; Changes from RFC v1: - The per-queue preemptible/express setting is moved to applicable qdiscs (Jakub Kicinski and others); - "min-frag-size" now follows the 802.3br specification more closely, it's expressed as X in '64(1 + X) + 4' (Joergen Andreasen); Another point that should be noted is the addition of the TC_SETUP_PREEMPT offload type, the idea behind this is to allow other qdiscs (was thinking of mqprio) to also configure which traffic classes should be marked as express/preemptible. Original cover letter: This is still an RFC because two main reasons, I want to confirm that this approach (per-queue settings via qdiscs, device settings via ethtool) looks good, even though there aren't much more options left ;-) The other reason is that while testing this I found some weirdness in the driver that I would need a bit more time to investigate. (In case these patches are not enough to give an idea of how things work, I can send the userspace patches, of course.) The idea of this "hybrid" approach is that applications/users would do the following steps to configure frame preemption: $ tc qdisc replace dev $IFACE parent root handle 100 taprio \ num_tc 3 \ map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \ queues 1@0 1@1 2@2 \ base-time $BASE_TIME \ sched-entry S 0f 10000000 \ preempt 1110 \ flags 0x2 The "preempt" parameter is the only difference, it configures which queues are marked as preemptible, in this example, queue 0 is marked as "not preemptible", so it is express, the rest of the four queues are preemptible. The next step, of this example, would be to enable frame preemption in the device, via ethtool, and set the minimum fragment size to 2: $ sudo ./ethtool --set-frame-preemption $IFACE fp on min-frag-size 2 Cheers, Vinicius Costa Gomes (8): ethtool: Add support for configuring frame preemption taprio: Add support for frame preemption offload igc: Set the RX packet buffer size for TSN mode igc: Only dump registers if configured to dump HW information igc: Avoid TX Hangs because long cycles igc: Add support for tuning frame preemption via ethtool igc: Add support for Frame Preemption offload igc: Separate TSN configurations that can be updated Documentation/networking/ethtool-netlink.rst | 38 +++++ drivers/net/ethernet/intel/igc/igc.h | 12 ++ drivers/net/ethernet/intel/igc/igc_defines.h | 6 + drivers/net/ethernet/intel/igc/igc_dump.c | 3 + drivers/net/ethernet/intel/igc/igc_ethtool.c | 53 ++++++ drivers/net/ethernet/intel/igc/igc_main.c | 31 +++- drivers/net/ethernet/intel/igc/igc_tsn.c | 162 ++++++++++++++----- drivers/net/ethernet/intel/igc/igc_tsn.h | 1 + include/linux/ethtool.h | 39 ++++- include/linux/netdevice.h | 1 + include/net/pkt_sched.h | 4 + include/uapi/linux/ethtool_netlink.h | 17 ++ include/uapi/linux/pkt_sched.h | 1 + net/ethtool/Makefile | 2 +- net/ethtool/common.c | 10 ++ net/ethtool/netlink.c | 19 +++ net/ethtool/netlink.h | 4 + net/ethtool/preempt.c | 146 +++++++++++++++++ net/sched/sch_taprio.c | 41 ++++- 19 files changed, 539 insertions(+), 51 deletions(-) create mode 100644 net/ethtool/preempt.c