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=-5.5 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT 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 86A2BC43381 for ; Thu, 21 Mar 2019 14:02:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4F5DE2183E for ; Thu, 21 Mar 2019 14:02:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=resnulli-us.20150623.gappssmtp.com header.i=@resnulli-us.20150623.gappssmtp.com header.b="qhl9qJms" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728069AbfCUOCk (ORCPT ); Thu, 21 Mar 2019 10:02:40 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:39589 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726787AbfCUOCk (ORCPT ); Thu, 21 Mar 2019 10:02:40 -0400 Received: by mail-wr1-f67.google.com with SMTP id j9so6725087wrn.6 for ; Thu, 21 Mar 2019 07:02:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=resnulli-us.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=0tmmfdCTkm91nCeui/lDM1f4KxiJyiRtYZdsSzeC2tk=; b=qhl9qJmshlx8ZhTyQovDVozMsZMYF2ge4mHghMLWd4pFXcPlHlDnxambWREpHvBfXU WunP/90e60lIWjK+EDpM/N6SIfy+PPBkNznyu4vX1Jo4PGPFrmLM4asQf/BC3AEuKZjg /K7aKx9n2rds/B5kD27IuWzDxH1wQK9fJ6ARvlHlOPdCbYPZGztCJ0oEcCFB9y9fnRnu wHSc0EyIgM2td4JKoxAxv7Kp0PYPkkQIhKey7JBABBhLQ8AJLAuNbZFLM4TyJHor4z7t QvhhxKqmeHyZH2OxEPmxJ01r1qjGvIsXrNFVHbvoWwd8mSlbZkEugILAAOy7sk8dYrDB Zbrw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=0tmmfdCTkm91nCeui/lDM1f4KxiJyiRtYZdsSzeC2tk=; b=WKrSF31J7cUKGzn2GbQ3nGwbvfyatb8hGOeFMqA0OvBwKIuLjuMt+/zF+9XXA17Hew Oq125OEDBS6NS7wpU0iiZipxxqQr5cSbEfbUPCCp+5F5fxsuOp1thvFDBYaS/3qGKeSx 4P8/L3nGSKxeap9y088nPD3shroE2jGaYRNrt/7mEjMmAoS9/laA7Mdp1LRnr22N8pbb cPMnOf5kicmlVAB1hEcu/VTXwUj2rTwqRBSYBXPluD3vgLAFAAS63Sg4XMMdvQ+Pauvn W2FBaHG0lGDHCxca+YUnw0sTbycH3XZQ1F+9/ThedH0/LKEZnFkMGoakmncWip6ALzUE UFQg== X-Gm-Message-State: APjAAAXgQsSkR6qqzP7TNTLnlwDCmVL0QZi7vhxUI3NvplL7Pd6GCdyi 3Dju0v+1mwbRJp7mufNNXlmQOg== X-Google-Smtp-Source: APXvYqwXGq3E1MbDNJ8UbRsfPiUJEI+J/B8orE3fvpMee9Mv7Mwtr2jcbqGkHv92vrIZMyGvlF1UfQ== X-Received: by 2002:a5d:4801:: with SMTP id l1mr2253285wrq.318.1553176958366; Thu, 21 Mar 2019 07:02:38 -0700 (PDT) Received: from localhost ([195.39.71.253]) by smtp.gmail.com with ESMTPSA id j66sm10918155wrj.51.2019.03.21.07.02.37 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 21 Mar 2019 07:02:37 -0700 (PDT) Date: Thu, 21 Mar 2019 14:51:57 +0100 From: Jiri Pirko To: Vlad Buslov Cc: netdev@vger.kernel.org, jhs@mojatatu.com, xiyou.wangcong@gmail.com, davem@davemloft.net, sbrivio@redhat.com Subject: Re: [PATCH net-next v3 01/12] net: sched: flower: don't check for rtnl on head dereference Message-ID: <20190321135157.GI2087@nanopsycho> References: <20190321131744.19224-1-vladbu@mellanox.com> <20190321131744.19224-2-vladbu@mellanox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190321131744.19224-2-vladbu@mellanox.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Thu, Mar 21, 2019 at 02:17:33PM CET, vladbu@mellanox.com wrote: >Flower classifier only changes root pointer during init and destroy. Cls >API implements reference counting for tcf_proto, so there is no danger of >concurrent access to tp when it is being destroyed, even without protection >provided by rtnl lock. > >Implement new function fl_head_dereference() to dereference tp->root >without checking for rtnl lock. Use it in all flower function that obtain >head pointer instead of rtnl_dereference(). > >Signed-off-by: Vlad Buslov >Reviewed-by: Stefano Brivio Acked-by: Jiri Pirko