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, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,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 27D15C433E2 for ; Thu, 3 Sep 2020 04:36:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C17320716 for ; Thu, 3 Sep 2020 04:36:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726111AbgICEgN (ORCPT ); Thu, 3 Sep 2020 00:36:13 -0400 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:58879 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725919AbgICEgN (ORCPT ); Thu, 3 Sep 2020 00:36:13 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04455;MF=xiaoguang.wang@linux.alibaba.com;NM=1;PH=DS;RN=3;SR=0;TI=SMTPD_---0U7mHhG3_1599107771; Received: from 30.225.32.185(mailfrom:xiaoguang.wang@linux.alibaba.com fp:SMTPD_---0U7mHhG3_1599107771) by smtp.aliyun-inc.com(127.0.0.1); Thu, 03 Sep 2020 12:36:11 +0800 Subject: Re: [PATCH] io_uring: don't hold fixed_file_data's lock when registering files To: Jens Axboe , io-uring@vger.kernel.org Cc: joseph.qi@linux.alibaba.com References: <20200902113256.6620-1-xiaoguang.wang@linux.alibaba.com> From: Xiaoguang Wang Message-ID: Date: Thu, 3 Sep 2020 12:35:53 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org hi， > 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? No, just found this by reading source codes. Regards, Xiaoguang Wang >