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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 0B189C352A3 for ; Thu, 13 Feb 2020 04:39:12 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B20742173E for ; Thu, 13 Feb 2020 04:39:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="tbYlCnFj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B20742173E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48J3gd56CgzDqSg for ; Thu, 13 Feb 2020 15:39:09 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux-foundation.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=akpm@linux-foundation.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=tbYlCnFj; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48J3gN269QzDqBS for ; Thu, 13 Feb 2020 15:38:55 +1100 (AEDT) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 18ED8206D7; Thu, 13 Feb 2020 04:38:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581568733; bh=bv+0VtaMuMuDtzLYPkieCdmd5QR4JDDM6y220mrx378=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=tbYlCnFj7ggSwK4cyg70rWxQrzUahCW2yOeoE3sZ/LlJjzcrzNUchpk3R5qfHHiaz SHB7larZ7765fztRfvP4xU4fKtp8W2fvEWd3ELQPm1bzbJvc27CPLFeH48zYRK25QU yPUch6WEdYHhO2730Z2ntH6BUkthDgGeRFY+B2E4= Date: Wed, 12 Feb 2020 20:38:52 -0800 From: Andrew Morton To: Matthew Wilcox Subject: Re: [PATCH 00/12] Change readahead API Message-Id: <20200212203852.8b7e0b28974e41227bd97329@linux-foundation.org> In-Reply-To: <20200125013553.24899-1-willy@infradead.org> References: <20200125013553.24899-1-willy@infradead.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cluster-devel@redhat.com, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-xfs@vger.kernel.org, linux-mm@kvack.org, ocfs2-devel@oss.oracle.com, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-btrfs@vger.kernel.org Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" On Fri, 24 Jan 2020 17:35:41 -0800 Matthew Wilcox wrote: > From: "Matthew Wilcox (Oracle)" > > This series adds a readahead address_space operation to eventually > replace the readpages operation. The key difference is that > pages are added to the page cache as they are allocated (and > then looked up by the filesystem) instead of passing them on a > list to the readpages operation and having the filesystem add > them to the page cache. It's a net reduction in code for each > implementation, more efficient than walking a list, and solves > the direct-write vs buffered-read problem reported by yu kuai at > https://lore.kernel.org/linux-fsdevel/20200116063601.39201-1-yukuai3@huawei.com/ Unclear which patch fixes this and how it did it?