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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 B1DFFC433E1 for ; Tue, 16 Jun 2020 05:24:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5987E206DB for ; Tue, 16 Jun 2020 05:24:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5987E206DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BA8626B0006; Tue, 16 Jun 2020 01:24:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B58CC6B0007; Tue, 16 Jun 2020 01:24:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A6E796B000C; Tue, 16 Jun 2020 01:24:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0032.hostedemail.com [216.40.44.32]) by kanga.kvack.org (Postfix) with ESMTP id 89FD46B0006 for ; Tue, 16 Jun 2020 01:24:31 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 32E9A1EE6 for ; Tue, 16 Jun 2020 05:24:31 +0000 (UTC) X-FDA: 76933934742.16.walk55_600103326dfc Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin16.hostedemail.com (Postfix) with ESMTP id EC903100E690B for ; Tue, 16 Jun 2020 05:24:30 +0000 (UTC) X-HE-Tag: walk55_600103326dfc X-Filterd-Recvd-Size: 3610 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Tue, 16 Jun 2020 05:24:30 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 934931F1; Mon, 15 Jun 2020 22:24:29 -0700 (PDT) Received: from [10.163.80.105] (unknown [10.163.80.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9105F3F6CF; Mon, 15 Jun 2020 22:24:27 -0700 (PDT) From: Anshuman Khandual Subject: Re: [PATCH] mm/pgtable: Move extern zero_pfn outside __HAVE_COLOR_ZERO_PAGE To: linux-mm@kvack.org Cc: Arnd Bergmann , linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , Mike Rapoport , "Kirill A . Shutemov" References: <1592280498-15442-1-git-send-email-anshuman.khandual@arm.com> Message-ID: Date: Tue, 16 Jun 2020 10:54:17 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1592280498-15442-1-git-send-email-anshuman.khandual@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: EC903100E690B X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 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 06/16/2020 09:38 AM, Anshuman Khandual wrote: > zero_pfn variable is required whether __HAVE_COLOR_ZERO_PAGE is enabled > or not. Also it should not really be declared individually in all functions > where it gets used. Just move the declaration outside, which also makes it > available for other potential users. > > Cc: Arnd Bergmann > Cc: linux-arch@vger.kernel.org > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Anshuman Khandual > --- > Applies on 5.8-rc1. If the earlier motivation was to hide zero_pfn from > general visibility, we could just put in a comment and update the commit > message that my_zero_pfn() should always be used rather than zero_pfn. > Build tested on many platforms and boot tested on arm64, x86. > > include/linux/pgtable.h | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index 32b6c52d41b9..078e9864abca 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -1020,10 +1020,11 @@ extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, > extern void untrack_pfn_moved(struct vm_area_struct *vma); > #endif > > +extern unsigned long zero_pfn; > + > #ifdef __HAVE_COLOR_ZERO_PAGE > static inline int is_zero_pfn(unsigned long pfn) > { > - extern unsigned long zero_pfn; > unsigned long offset_from_zero_pfn = pfn - zero_pfn; > return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); > } > @@ -1033,13 +1034,11 @@ static inline int is_zero_pfn(unsigned long pfn) > #else > static inline int is_zero_pfn(unsigned long pfn) > { > - extern unsigned long zero_pfn; > return pfn == zero_pfn; > } > > static inline unsigned long my_zero_pfn(unsigned long addr) > { > - extern unsigned long zero_pfn; > return zero_pfn; > } > #endif > The CC list is incomplete. Adding Andrew, Mike and Kirill. +Cc: Andrew Morton +Cc: Mike Rapoport +Cc: Kirill A . Shutemov Will update the CC list next time around. - Anshuman