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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 A28ECC43461 for ; Sat, 17 Apr 2021 21:29:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2029161352 for ; Sat, 17 Apr 2021 21:29:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2029161352 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A50956B0036; Sat, 17 Apr 2021 17:29:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9DA826B006E; Sat, 17 Apr 2021 17:29:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 82C4A6B0070; Sat, 17 Apr 2021 17:29:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0213.hostedemail.com [216.40.44.213]) by kanga.kvack.org (Postfix) with ESMTP id 635BB6B0036 for ; Sat, 17 Apr 2021 17:29:06 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 1064D75B5 for ; Sat, 17 Apr 2021 21:29:06 +0000 (UTC) X-FDA: 78043149492.13.E37936E Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf26.hostedemail.com (Postfix) with ESMTP id A8C6640002C8 for ; Sat, 17 Apr 2021 21:28:59 +0000 (UTC) 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=tdMd9G9wD3dHdDB049z0mEp3bwlE87mJ0J7o89xl/iU=; b=kjCBnWRnNfJ4jh1gNX/lQqFZaV PIt6sDdbkDGzgmh71GE65C7gRjevycey4DoCtbejN9tL9oy21OFCEaAalEL1tJX2o90jMIunwvzlT aw6WnoUC4xKa/S6Fo+ZMatucihabyUEWmzgS2fQA3KuKU2AamMDSAvwzszyCc5I4TnWdPWLrwWCKi rVT5becyLy4eWu5C3CPFKJcjpScabeN83QGn+BwxjvQCu6su18nAbnPuTOLaKIYZFme9zSXfjcKXe HVFpVtf65QAh/PF06VB9QUA3eZMEV6/SGt6UIGiIg++xfTnOleyRsiTg4gP470cAho43TKpegokfh QjMDTCHQ==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lXsUd-00BiOm-RD; Sat, 17 Apr 2021 21:28:45 +0000 Date: Sat, 17 Apr 2021 22:28:43 +0100 From: Matthew Wilcox To: David Laight Cc: "brouer@redhat.com" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "netdev@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" , "linux-mips@vger.kernel.org" , "ilias.apalodimas@linaro.org" , "mcroce@linux.microsoft.com" , "grygorii.strashko@ti.com" , "arnd@kernel.org" , "hch@lst.de" , "linux-snps-arc@lists.infradead.org" , "mhocko@kernel.org" , "mgorman@suse.de" Subject: Re: [PATCH 2/2] mm: Indicate pfmemalloc pages in compound_head Message-ID: <20210417212843.GT2531743@casper.infradead.org> References: <20210416230724.2519198-1-willy@infradead.org> <20210416230724.2519198-3-willy@infradead.org> <2a531a42f23e4046833e0feb8faef0b5@AcuMS.aculab.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2a531a42f23e4046833e0feb8faef0b5@AcuMS.aculab.com> X-Rspamd-Queue-Id: A8C6640002C8 X-Stat-Signature: ch71tyic6zgzy13py5g4tdtfn3qwkpbu X-Rspamd-Server: rspam02 Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf26; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1618694939-375198 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000002, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, Apr 17, 2021 at 09:13:45PM +0000, David Laight wrote: > > struct { /* page_pool used by netstack */ > > - /** > > - * @dma_addr: might require a 64-bit value on > > - * 32-bit architectures. > > - */ > > + unsigned long pp_magic; > > + unsigned long xmi; > > + unsigned long _pp_mapping_pad; > > unsigned long dma_addr[2]; > > }; > > You've deleted the comment. Yes. It no longer added any value. You can see dma_addr now occupies two words. > I also think there should be a comment that dma_addr[0] > must be aliased to ->index. That's not a requirement. Moving the pfmemalloc indicator is a requirement so that we _can_ use index, but there's no requirement about how index is used.