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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 EE887C32771 for ; Sun, 19 Jan 2020 03:15:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA5122082F for ; Sun, 19 Jan 2020 03:15:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728668AbgASDPa (ORCPT ); Sat, 18 Jan 2020 22:15:30 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:9661 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726827AbgASDPa (ORCPT ); Sat, 18 Jan 2020 22:15:30 -0500 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id B9E93D6B0EE9A4D5440E; Sun, 19 Jan 2020 11:15:27 +0800 (CST) Received: from [127.0.0.1] (10.173.220.96) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.439.0; Sun, 19 Jan 2020 11:15:19 +0800 Subject: Re: [RFC] iomap: fix race between readahead and direct write To: Gao Xiang CC: Matthew Wilcox , , , , , , , , References: <20200116063601.39201-1-yukuai3@huawei.com> <20200118230826.GA5583@bombadil.infradead.org> <20200119014213.GA16943@bombadil.infradead.org> <64d617cc-e7fe-6848-03bb-aab3498c9a07@huawei.com> <20200119030123.GA223124@architecture4> From: "yukuai (C)" Message-ID: Date: Sun, 19 Jan 2020 11:15:18 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20200119030123.GA223124@architecture4> Content-Type: text/plain; charset="gbk"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.220.96] X-CFilter-Loop: Reflected Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On 2020/1/19 11:01, Gao Xiang wrote: > IMO, if use_list == true, it will call read_pages -> .readpages > and go just like the current implementation. The problem is that in the current implementatin, iomap_next_page() add page to page cache and it is replaced with readahead_page() Thanks! Yu Kuai