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=-3.8 required=3.0 tests=BAYES_00, 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 9BA41C43381 for ; Tue, 16 Mar 2021 21:46:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 511B664F9D for ; Tue, 16 Mar 2021 21:46:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229586AbhCPVp5 (ORCPT ); Tue, 16 Mar 2021 17:45:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229558AbhCPVpl (ORCPT ); Tue, 16 Mar 2021 17:45:41 -0400 Received: from mail.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 412A0C06174A; Tue, 16 Mar 2021 14:45:40 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) by mail.monkeyblade.net (Postfix) with ESMTPSA id 742724D04126B; Tue, 16 Mar 2021 14:45:37 -0700 (PDT) Date: Tue, 16 Mar 2021 14:45:33 -0700 (PDT) Message-Id: <20210316.144533.1015318495899101097.davem@davemloft.net> To: linyunsheng@huawei.com Cc: kuba@kernel.org, jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linuxarm@openeuler.org Subject: Re: [PATCH net-next] net: sched: remove unnecessay lock protection for skb_bad_txq/gso_skb From: David Miller In-Reply-To: <1fea8225-69b0-5a73-0e9d-f5bfdecdc840@huawei.com> References: <1615800610-34700-1-git-send-email-linyunsheng@huawei.com> <20210315.164151.1093629330365238718.davem@redhat.com> <1fea8225-69b0-5a73-0e9d-f5bfdecdc840@huawei.com> X-Mailer: Mew version 6.8 on Emacs 27.1 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-4.6.2 (mail.monkeyblade.net [0.0.0.0]); Tue, 16 Mar 2021 14:45:37 -0700 (PDT) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yunsheng Lin Date: Tue, 16 Mar 2021 10:40:56 +0800 > On 2021/3/16 7:41, David Miller wrote: >> From: Yunsheng Lin > > At least for the fast path, taking two locks for lockless qdisc hurts > performance when handling requeued skb, especially if the lockless > qdisc supports TCQ_F_CAN_BYPASS. The bad txq and gro skb cases are not "fast path", sorry