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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 BD925C55178 for ; Fri, 6 Nov 2020 08:07:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2E180208C3 for ; Fri, 6 Nov 2020 08:07:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2E180208C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A98FF6B0072; Fri, 6 Nov 2020 03:07:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A47F16B0074; Fri, 6 Nov 2020 03:07:19 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8E9496B0075; Fri, 6 Nov 2020 03:07:19 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0037.hostedemail.com [216.40.44.37]) by kanga.kvack.org (Postfix) with ESMTP id 5E3256B0072 for ; Fri, 6 Nov 2020 03:07:19 -0500 (EST) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 0FA59181AEF07 for ; Fri, 6 Nov 2020 08:07:19 +0000 (UTC) X-FDA: 77453263398.15.son30_180272b272d1 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin15.hostedemail.com (Postfix) with ESMTP id CF6521814B0C1 for ; Fri, 6 Nov 2020 08:07:18 +0000 (UTC) X-HE-Tag: son30_180272b272d1 X-Filterd-Recvd-Size: 1275 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by imf31.hostedemail.com (Postfix) with ESMTP for ; Fri, 6 Nov 2020 08:07:18 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 74F7468C4E; Fri, 6 Nov 2020 09:07:16 +0100 (CET) Date: Fri, 6 Nov 2020 09:07:15 +0100 From: Christoph Hellwig To: "Matthew Wilcox (Oracle)" Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, hch@lst.de, kent.overstreet@gmail.com Subject: Re: [PATCH v2 02/18] mm/filemap: Remove dynamically allocated array from filemap_read Message-ID: <20201106080715.GB31585@lst.de> References: <20201104204219.23810-1-willy@infradead.org> <20201104204219.23810-3-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201104204219.23810-3-willy@infradead.org> User-Agent: Mutt/1.5.17 (2007-11-01) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Nov 04, 2020 at 08:42:03PM +0000, Matthew Wilcox (Oracle) wrote: > Increasing the batch size runs into diminishing returns. It's probably > better to make, eg, three calls to filemap_get_pages() than it is to > call into kmalloc(). Yes, this always looked weird. Reviewed-by: Christoph Hellwig