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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 97F9FC433E7 for ; Wed, 2 Sep 2020 14:14:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71E5520829 for ; Wed, 2 Sep 2020 14:14:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="LPGSwWmg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727918AbgIBOOo (ORCPT ); Wed, 2 Sep 2020 10:14:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728018AbgIBONt (ORCPT ); Wed, 2 Sep 2020 10:13:49 -0400 Received: from mail-il1-x143.google.com (mail-il1-x143.google.com [IPv6:2607:f8b0:4864:20::143]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB48AC061244 for ; Wed, 2 Sep 2020 07:13:48 -0700 (PDT) Received: by mail-il1-x143.google.com with SMTP id t4so5103720iln.1 for ; Wed, 02 Sep 2020 07:13:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=nstCY4nIMGGeVDnHDWDgzvmoTV+BfwbaS7kuM1aizm0=; b=LPGSwWmgJZ3FdeZClvznODeiRKPC7C/3kuwCVtqP7ePneuiH22OrpnfMunvOzZvEM5 9GnXvsxqKxtF0nkohr8NgjqZRy28AWhz+BNdHIOEBfa2F9VjHVMPICCRgZtQRmTALdvQ ZmPZyfpcj8MzF2yvMY4gadJ0kd+fDCBuE6b2Y1YjH4cmwVMksNlHWClwpT8ohh++BFy8 2O2ZxYEVi+HTKdG+e0T+8Lveg9gkPOAzkl7JnSUjg5gHfud2+o5VGDUwcZsvELpbbrts uZpGrTYD+1jTLBTWOPtuRcdhp+5tq3EodO5UoUEp5eBTRQFfd0CLbs8OobGYUWBNyAIi QBDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=nstCY4nIMGGeVDnHDWDgzvmoTV+BfwbaS7kuM1aizm0=; b=B4C174GzJDvN1a6D2YxMu6fpQ/1+Kt7ecQP/T1VYIfI3VM8hlPsLFmhtH4S2IELeCI /ks1ioMgUbPzGBOqow1TzFibiJqIxFjUcqpdEFhvTH9+6CPI3aS8RfGd2+pIgTF3/Ujg rIwQ6sxhgqOSSMKSN1g/BoaCMVcw/rpgxvv7Es7TmzGKDfSCM9P6eFGuMC98+aSCOO5A 9ulhPRL+y8TkKpkD3XRJ2Dp5nofFOJHNmtvaa0OvWU9n+d3E/JxWQM2S5tGQDITUHoQX y4KH8e4eypGjDeQCT5PAedSC7IZY1RlDYL0PC3cKtsFJWBhWxvodCnKXqJVOEAc1ZZnX aFHw== X-Gm-Message-State: AOAM531dDEmgQUMLo0bwghcWbcGO81mJbIlZY/UA0nKlPrL5KglFbBOz BE3En/eYCaiQojET8R1Ik1Eqz9huk1W3nhlT X-Google-Smtp-Source: ABdhPJw1OS5azBOxnbzb9W8hUefLyNrP7SkyRpuZ1ySX22X0u0NVUpeYn/jdLZILm8vWDpCOSlghkg== X-Received: by 2002:a92:7113:: with SMTP id m19mr3851824ilc.175.1599056025493; Wed, 02 Sep 2020 07:13:45 -0700 (PDT) Received: from [192.168.1.57] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id f10sm2245854ilk.11.2020.09.02.07.13.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Sep 2020 07:13:45 -0700 (PDT) Subject: Re: [PATCH] io_uring: don't hold fixed_file_data's lock when registering files To: Xiaoguang Wang , io-uring@vger.kernel.org Cc: joseph.qi@linux.alibaba.com References: <20200902113256.6620-1-xiaoguang.wang@linux.alibaba.com> From: Jens Axboe Message-ID: Date: Wed, 2 Sep 2020 08:13:44 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200902113256.6620-1-xiaoguang.wang@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 9/2/20 5:32 AM, Xiaoguang Wang wrote: > While registering new files by IORING_REGISTER_FILES, there're not > valid fixed_file_ref_node at the moment, so it's unnecessary to hold > fixed_file_data's lock when registering files. Even if that were the case (I haven't looked too closely at it yet), it would a) need a big comment explaining why, and b) some justification on why this would be a change we'd want to make. On b, are you seeing any tangible differences with this? -- Jens Axboe