Received: by 2002:a05:6a10:f3d0:0:0:0:0 with SMTP id a16csp4082097pxv; Mon, 5 Jul 2021 13:19:26 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxZTdCi++Z8zVbFqlZQVRnSZ4JWNqknFUrzOBQAgQJF48ObEnCZN2hV/RGIfNGJJSOP9N/0 X-Received: by 2002:a50:8a9e:: with SMTP id j30mr18102346edj.72.1625516366228; Mon, 05 Jul 2021 13:19:26 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1625516366; cv=none; d=google.com; s=arc-20160816; b=bAi3mn/ZWRNpI7Q5DZyibuKeF8xjqW/DE2HDwRfJdIQGuDsx2osxOMPaweRJ2SwuMU uy9a/dj7jUaUU2bNfbdBaaEAfglyEeHFRyqgTMJzS8AhNxXNU1cnqeRfpuTbUHxMB1C1 wNWv6UHhpYmYTIUuQ86alaak2Mxx7vyB9T6+FGQJWZlnWZEAMYGiB6OFYt20Mq7T74Kf W66/MRVXRSL8t5CcZmy7+xYRVptE/dFhoqdJxlVBtZiCbLdxia75ZiDhVWOGrE3r4kPn /n5OKaQY1l21HCav4Dh3RDoQvJIfHXYjmlOP7LyEtOkwtv+CysZ2LFDwKFmYF8BQfbYS QIxg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=cHJoMBPoqsS6VIVZNAuTsCESFJ7feq3dFA9cLcq4xmA=; b=daf+2lQ6RpQGpK/X3yC1GF3ZqCtz0nhdZLX+J+O8gr58WFhgMa8G/fhqQabz5tgTJl qrkLvNMm2JD4DQoyOO+YPBMM683Zw0Xck39kvKBA05QHpkQo819ZDEoJXSTkft5LfQ/N SC/ZtI2Gsd5SGlxkgjLrtgxKhw2G3tNKaHLMG6vzZarjf9bL/y56JewM7ralA0fnoOEg COFb/JVJwUBDi3ABbbOJ3Gj1GEbBMKou5C10tVDEdqP5tL2qkWU/Kn2pFeGq5VqpDrn7 CrFiEzT5DRSBJyVjMrj2+faenHyLLLt8UVkIL49tGBNmJjHWYDvp2erUJzn/qqfy5prC LqLw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=D1zngPFj; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id em10si12252887ejc.186.2021.07.05.13.19.01; Mon, 05 Jul 2021 13:19:26 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=D1zngPFj; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229898AbhGEUS2 (ORCPT + 99 others); Mon, 5 Jul 2021 16:18:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229565AbhGEUS1 (ORCPT ); Mon, 5 Jul 2021 16:18:27 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38B4DC061574 for ; Mon, 5 Jul 2021 13:15:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=cHJoMBPoqsS6VIVZNAuTsCESFJ7feq3dFA9cLcq4xmA=; b=D1zngPFjaraCLiltD0U9yxBX5A kIMC9/R+DfJbPFWbxRozfUqe9136feg/Kr6BoNXvWvtm/XIW9SwZy3izXGiMYCgWX+Ym70KenbpQe ezSvZvnaCC45B/8btVNs0RScJA+xPsaH6ZVm//YELSSSRsIGiF/n9SEIf64hLzXAtyhalxU1R49UP APxCJJwB0JQTQbNK9VuINLaYN0QwlCF3ghVn6R29hMefxMlqdcbOhE9Xc/XZ37+y+6n/GVaUfnOog ZzedbwMTrw5xZZIGrhjzjZrDMftyygVn/lfgKTBG1X6Yo/v6gs0hubZQs35II+taREN02/LF6NSzi F03mz0wQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1m0V02-00AZ6w-Fs; Mon, 05 Jul 2021 20:15:36 +0000 Date: Mon, 5 Jul 2021 21:15:26 +0100 From: Matthew Wilcox To: Gao Xiang Cc: linux-erofs@lists.ozlabs.org, LKML Subject: Re: [RFC PATCH 2/2] erofs: directly traverse pages in z_erofs_readahead() Message-ID: References: <20210705183253.14833-1-xiang@kernel.org> <20210705183253.14833-2-xiang@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210705183253.14833-2-xiang@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 06, 2021 at 02:32:53AM +0800, Gao Xiang wrote: > In that way, pages can be accessed directly with xarray. I didn't mean "open code readahead_page()". I meant "Wouldn't it be great if z_erofs_do_read_page() used readahead_expand() in order to allocate the extra pages in the extents that cover the start and end of the requested chunk". That way the pages would already be in the page cache for subsequent reads.