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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 47240C433ED for ; Tue, 6 Apr 2021 01:50:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0CA3B61382 for ; Tue, 6 Apr 2021 01:50:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242256AbhDFBuV (ORCPT ); Mon, 5 Apr 2021 21:50:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242189AbhDFBuR (ORCPT ); Mon, 5 Apr 2021 21:50:17 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D758C06174A; Mon, 5 Apr 2021 18:50:10 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id z12so2545195plb.9; Mon, 05 Apr 2021 18:50:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Eowwc3RTaC+FslHD4Qh04BdYDZupvDIB3d1BWbq0KkQ=; b=hYESA+HWCG79Jwc7bhgy4xSr59ByZRrDvtvRCAj1p2zA2UBTQvhZQsZKXVLSKBZxTP xQHnefJfwfLXq1FoShve71fs8UB75vCZd+yvIICm2GCqahOnw0jQgBy+5wtZAAUotlhY d/m5Z8GCRNdnUuKV/BKE6yf5/QKKJKsgastv5IVIlEGiUDmtWh4z0RHAj003HtvAER7H F3EACvkF6YBiJiVXECLq8w6sUUY0L4Dqxs4LXIo/7T6S0Y8/6fJYcDc9VJ3iZfCDJrXZ XR6boO8zabi/bg14+pmBg52ZQnQhuXAc3GnSvT5CWz83aQTuZQEDGCikBHuIVYT+caJK /h2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Eowwc3RTaC+FslHD4Qh04BdYDZupvDIB3d1BWbq0KkQ=; b=CZ22oFXsTZj0xG+6Nu6eGEBg7QkTzTXDpFLkS/oa7800Wk6uDrYocVWV8r6VyN/WFz ZRRURQ9J1FaFMnULb/KW6dSXE+lUiAx3LwAFggoFJfAwinhiVuyOpe9MRp9lo7pYtiRD OfCnytcs/e6wiCzxHzvD4JnHc+3GngQssHqOZWHSIjBLV4dUKA5igicEOuVkw9IDXm9v Y5JCV/zVqgc9xxCO6eJ5Ab3FzmxmZ3OceNwdfbyQCH0xUktruXXUjKWT0GmwGorI5N7/ QEPZR0m9utluyjRbkqjvrhtgwVnB1/oiuCuzKbQiiAeVuKRBJmxn/CbK5Nm5iKig/RRE ma8g== X-Gm-Message-State: AOAM533XY/1vMWoSKayUb/0a8Jaw5GYGcdmP8H9YtH4zJpIGEvA4TZoc we1/7nRVGPaEkfylsvPYIrQ8o2H2/E/9Xsqfhy0= X-Google-Smtp-Source: ABdhPJxZ/l4tgfJvTf8QzJwOEoTbtfTwski+LA7UnDuNujUz1LWfnLHLP/dCrgtjpcl04zdwZVv0RshNFzinnP04c8M= X-Received: by 2002:a17:90a:31cd:: with SMTP id j13mr1979538pjf.231.1617673809892; Mon, 05 Apr 2021 18:50:09 -0700 (PDT) MIME-Version: 1.0 References: <465a540e-5296-32e7-f6a6-79942dfe2618@netrounds.com> <20200825032312.11776-1-hdanton@sina.com> <20200825162329.11292-1-hdanton@sina.com> <5f46032e.1c69fb81.9880c.7a6cSMTPIN_ADDED_MISSING@mx.google.com> <20200827125747.5816-1-hdanton@sina.com> <5f51cbad3cc2_3eceb208fc@john-XPS-13-9370.notmuch> <20210403003537.2032-1-hdanton@sina.com> In-Reply-To: From: Cong Wang Date: Mon, 5 Apr 2021 18:49:58 -0700 Message-ID: Subject: Re: Packet gets stuck in NOLOCK pfifo_fast qdisc To: Jiri Kosina Cc: Hillf Danton , John Fastabend , Paolo Abeni , Kehuan Feng , Jike Song , Jonas Bonn , Michael Zhivich , David Miller , LKML , Michal Kubecek , Netdev , Josh Hunt , Yunsheng Lin Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Apr 3, 2021 at 5:23 AM Jiri Kosina wrote: > > I am still planning to have Yunsheng Lin's (CCing) fix [1] tested in the > coming days. If it works, then we can consider proceeding with it, > otherwise I am all for reverting the whole NOLOCK stuff. > > [1] https://lore.kernel.org/linux-can/1616641991-14847-1-git-send-email-linyunsheng@huawei.com/T/#u I personally prefer to just revert that bit, as it brings more troubles than gains. Even with Yunsheng's patch, there are still some issues. Essentially, I think the core qdisc scheduling code is not ready for lockless, just look at those NOLOCK checks in sch_generic.c. :-/ Thanks.