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=-5.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 6A66BC433DF for ; Thu, 14 May 2020 09:37:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40A1E206A5 for ; Thu, 14 May 2020 09:37:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cogentembedded-com.20150623.gappssmtp.com header.i=@cogentembedded-com.20150623.gappssmtp.com header.b="oVWM6T5q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726056AbgENJhl (ORCPT ); Thu, 14 May 2020 05:37:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725925AbgENJhl (ORCPT ); Thu, 14 May 2020 05:37:41 -0400 Received: from mail-lf1-x142.google.com (mail-lf1-x142.google.com [IPv6:2a00:1450:4864:20::142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98A84C061A0E for ; Thu, 14 May 2020 02:37:40 -0700 (PDT) Received: by mail-lf1-x142.google.com with SMTP id a4so2000332lfh.12 for ; Thu, 14 May 2020 02:37:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cogentembedded-com.20150623.gappssmtp.com; s=20150623; h=subject:from:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=7Gj0cNxCY34MN1EL7DKRnwUOlinn6Wz+qtY7EpWgz5M=; b=oVWM6T5qZTorNnMZprnZOFTQiXbb4XbmVvFkT7FzHv9IpJGm8S3O+vQnaZOON2iK3v JJmYe7DK9Kk46bakSudSmewV9tYtLrAJelqpH90nTEdK2VJU3z6p2veVBw9i0Pj4qfEh 25uwitsnpu/9GZtCVbF36DKWxme9aL/hXO6yHQsnOG0ZXJSywTZkNd1u+E++RrTVQxC9 330RYbOiJgbJfDg3T3sM7JDfeCyw9Q8urwfZ41UHPSQPqE2rwNz8O/KoBuF/DGcQlocl YXFSZJnthWJx1Vs86AyjOBu1d4/4wAF6O8Oztf1P0XGe9SnW5ZMdrNJfBTMwe1BE0Yyt 41bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=7Gj0cNxCY34MN1EL7DKRnwUOlinn6Wz+qtY7EpWgz5M=; b=OsZ/TW5u/rvDPOywr2vRh+Ki/X3u6ZVwS8TzLfTJYVzdw3r9kLfOUiHlnz7Wqh7YMq jutrLhIcKB3JSD5meWTCWVosKjdI2o5ULw8lotrIob6MpQnmJ11ha3vtc11RGsiW+hJc IP8EF7ssN/zHc1Ngxl4d9iTPTMd8jehHsk6z7BZvd51KnQ/kE2jjNezwUGk29mM69YA9 KDs7tY6uwHY6fMdibUZ53je8FtsxEi7sXrcUu7PguGNgkOWHwoRrmTKp7R7IBm0+qc4I ev7gGg0oOrdPQUJbjZI/jgJTVFX+9yzGm7RocHJoSkiZSNbJBVHQp0Pk57MoFwGwt9S8 Jj1Q== X-Gm-Message-State: AOAM531+aKqpReoDPNSWyQuhCHgpFssTv5iHIAAZWw/MzWwx7brkPtca nZZ1fQgyLywZbUSQpnKCEV+EhZBG2Xo= X-Google-Smtp-Source: ABdhPJwxSDqV5OeLS9W2cuCCEbpgT+k+80gl6sncjS9yh7y8GD02pIYkoXe52KVnpd8P8A4t9cCOIw== X-Received: by 2002:a19:8107:: with SMTP id c7mr1198346lfd.38.1589449058740; Thu, 14 May 2020 02:37:38 -0700 (PDT) Received: from ?IPv6:2a00:1fa0:428e:17ae:1023:2fd9:377b:94c8? ([2a00:1fa0:428e:17ae:1023:2fd9:377b:94c8]) by smtp.gmail.com with ESMTPSA id d16sm1172540ljj.84.2020.05.14.02.37.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 14 May 2020 02:37:38 -0700 (PDT) Subject: Re: [PATCH] MIPS: update tlb even if pte entry has no change From: Sergei Shtylyov To: Bibo Mao , Thomas Bogendoerfer , Andrew Morton , Paul Burton , Dmitry Korotin , =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= , Stafford Horne , Steven Price , Anshuman Khandual , Mike Rapoport Cc: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org References: <1589422677-11455-1-git-send-email-maobibo@loongson.cn> Message-ID: Date: Thu, 14 May 2020 12:37:27 +0300 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14.05.2020 12:35, Sergei Shtylyov wrote: >> From: bibo mao >> >> If there are two threads reading the same memory and tlb miss happens, >> one thread fills pte entry, the other reads new pte value during page fault >> handling. PTE value may be updated before page faul, so the process need > >    Fault. And "needs". >> need update tlb still. Oh, and one "need" is enough. :-) >> Also this patch define flush_tlb_fix_spurious_fault as empty, since it not >> necessary to flush the page for all CPUs >> >> Signed-off-by: Bibo Mao > [...] MBR, Sergei