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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 D83B2C41514 for ; Tue, 13 Aug 2019 16:50:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B27B920844 for ; Tue, 13 Aug 2019 16:50:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727995AbfHMQt7 (ORCPT ); Tue, 13 Aug 2019 12:49:59 -0400 Received: from ale.deltatee.com ([207.54.116.67]:51090 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726769AbfHMQt7 (ORCPT ); Tue, 13 Aug 2019 12:49:59 -0400 Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1hxZzc-0000UT-Fb; Tue, 13 Aug 2019 10:49:53 -0600 To: Paul Walmsley Cc: Greentime Hu , Rob Herring , Albert Ou , Andrew Waterman , Palmer Dabbelt , Linux Kernel Mailing List , Stephen Bates , Olof Johansson , greentime.hu@sifive.com, linux-riscv@lists.infradead.org, Michael Clark , Christoph Hellwig , linux-mm@vger.kernel.org References: <20190109203911.7887-1-logang@deltatee.com> <20190109203911.7887-3-logang@deltatee.com> <0926a261-520e-4c40-f926-ddd40bb8ce44@deltatee.com> <96156909-1453-d487-ff66-a041d67c74d6@deltatee.com> <5506c875-9387-acc9-a7fe-5b7c10036c40@deltatee.com> From: Logan Gunthorpe Message-ID: Date: Tue, 13 Aug 2019 10:49:51 -0600 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: linux-mm@vger.kernel.org, hch@lst.de, michaeljclark@mac.com, linux-riscv@lists.infradead.org, greentime.hu@sifive.com, olof@lixom.net, sbates@raithlin.com, linux-kernel@vger.kernel.org, palmer@sifive.com, andrew@sifive.com, aou@eecs.berkeley.edu, robh@kernel.org, green.hu@gmail.com, paul.walmsley@sifive.com X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [PATCH v4 2/2] RISC-V: Implement sparsemem X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-08-13 10:39 a.m., Paul Walmsley wrote: > On Tue, 13 Aug 2019, Logan Gunthorpe wrote: > >> On 2019-08-13 12:04 a.m., Greentime Hu wrote: >> >>> Every architecture with mmu defines their own pfn_valid(). >> >> Not true. Arm64, for example just uses the generic implementation in >> mmzone.h. > > arm64 seems to define their own: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/Kconfig#n899 Oh, yup. My mistake. > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/mm/init.c#n235 > > While there are many architectures which have their own pfn_valid(); > oddly, almost none of them set HAVE_ARCH_PFN_VALID ? Yes, much of this is super confusing. Seems HAVE_ARCH_PFN_VALID only matters if SPARSEMEM is set. So risc-v probably doesn't need to set it and we just need a #ifdef !CONFIG_FLATMEM around the pfn_valid definition like other arches. Logan