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=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 4083FC4321A for ; Fri, 28 Jun 2019 21:46:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DA96208CB for ; Fri, 28 Jun 2019 21:46:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726695AbfF1Vqt (ORCPT ); Fri, 28 Jun 2019 17:46:49 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:52428 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726557AbfF1Vqs (ORCPT ); Fri, 28 Jun 2019 17:46:48 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 1304813CB3330; Fri, 28 Jun 2019 14:46:48 -0700 (PDT) Date: Fri, 28 Jun 2019 14:46:47 -0700 (PDT) Message-Id: <20190628.144647.570493656550419800.davem@davemloft.net> To: vedang.patel@intel.com Cc: netdev@vger.kernel.org, jeffrey.t.kirsher@intel.com, jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, intel-wired-lan@lists.osuosl.org, vinicius.gomes@intel.com, l@dorileo.org, jakub.kicinski@netronome.com, m-karicheri2@ti.com, sergei.shtylyov@cogentembedded.com, eric.dumazet@gmail.com, aaron.f.brown@intel.com Subject: Re: [PATCH net-next v6 0/8] net/sched: Add txtime-assist support for taprio. From: David Miller In-Reply-To: <1561500439-30276-1-git-send-email-vedang.patel@intel.com> References: <1561500439-30276-1-git-send-email-vedang.patel@intel.com> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Fri, 28 Jun 2019 14:46:48 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vedang Patel Date: Tue, 25 Jun 2019 15:07:11 -0700 > Currently, we are seeing packets being transmitted outside their > timeslices. We can confirm that the packets are being dequeued at the right > time. So, the delay is induced after the packet is dequeued, because > taprio, without any offloading, has no control of when a packet is actually > transmitted. > > In order to solve this, we are making use of the txtime feature provided by > ETF qdisc. Hardware offloading needs to be supported by the ETF qdisc in > order to take advantage of this feature. The taprio qdisc will assign > txtime (in skb->tstamp) for all the packets which do not have the txtime > allocated via the SO_TXTIME socket option. For the packets which already > have SO_TXTIME set, taprio will validate whether the packet will be > transmitted in the correct interval. > > In order to support this, the following parameters have been added: > - flags (taprio): This is added in order to support different offloading > modes which will be added in the future. > - txtime-delay (taprio): This indicates the minimum time it will take for > the packet to hit the wire after it reaches taprio_enqueue(). This is > useful in determining whether we can transmit the packet in the remaining > time if the gate corresponding to the packet is currently open. > - skip_skb_check (ETF): ETF currently drops any packet which does not have > the SO_TXTIME socket option set. This check can be skipped by specifying > this option. ... Series applied, thanks.