From patchwork Fri Dec 14 11:10:05 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 10730897 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A5B3114E2 for ; Fri, 14 Dec 2018 11:11:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9241F2D412 for ; Fri, 14 Dec 2018 11:11:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 825752D42B; Fri, 14 Dec 2018 11:11:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 2225D2D41D for ; Fri, 14 Dec 2018 11:11:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=4s3WQJL/yBEU1o7D2FL6CApJVzZegPqz2ud1+wWqWxk=; b=qaN Hfq63B/kU7RxmD+TEIy18QHf8AL94+ki2zCGRntYhJYNiG5PXUWNTfufWLU7pvtKDMXQ/0V/Dr+v7 Z6gsPGKI86ZCgflCimqY6I4n0s7eO0TGRRJZFOXsM50Wunr6T6bgqD9M59+8FLEORwASqcdfU+EtO keS1hwOh/n5BhpaR3eATi1Q6ovC3MLyyfadLqDp3OR9Pjv6CsBuaSjCAc+xaQt+cvv82IFKcsPLWF S0K+dt+7tdwjVjfXPQAtGclN4dFXaGBBdHCLy5WWejoDtU5NRybcv0tg2qhzkBKYeicN7g0c2n5xC N6cHTusUVd/roQLi7mSF2FmoWXwHpRA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXlNW-0008CR-JM; Fri, 14 Dec 2018 11:11:34 +0000 Received: from mx1.redhat.com ([209.132.183.28]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXlMs-0007Wv-Jg; Fri, 14 Dec 2018 11:10:57 +0000 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A15C746263; Fri, 14 Dec 2018 11:10:40 +0000 (UTC) Received: from t460s.redhat.com (ovpn-117-139.ams2.redhat.com [10.36.117.139]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9B90A5DA2A; Fri, 14 Dec 2018 11:10:15 +0000 (UTC) From: David Hildenbrand To: linux-mm@kvack.org Subject: [PATCH v1 0/9] mm: PG_reserved cleanups and documentation Date: Fri, 14 Dec 2018 12:10:05 +0100 Message-Id: <20181214111014.15672-1-david@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Fri, 14 Dec 2018 11:10:43 +0000 (UTC) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181214_031054_692398_C726922A X-CRM114-Status: GOOD ( 12.79 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Michal Hocko , CHANDAN VN , David Hildenbrand , David Airlie , Benjamin Herrenschmidt , Bhupesh Sharma , Palmer Dabbelt , Heiko Carstens , Stefan Agner , Michal Hocko , David Howells , Paul Mackerras , Michael Ellerman , linux-riscv@lists.infradead.org, Alexander Duyck , linux-s390@vger.kernel.org, Florian Fainelli , Vasily Gorbik , Logan Gunthorpe , Pavel Tatashin , Matthew Wilcox , AKASHI Takahiro , Geert Uytterhoeven , Catalin Marinas , Anthony Yznaga , Tobias Klauser , Laura Abbott , Fenghua Yu , Albert Ou , Kees Cook , Arnd Bergmann , Stephen Rothwell , Marc Zyngier , Will Deacon , Kristina Martsenko , linux-m68k@lists.linux-m68k.org, Dave Kleikamp , linux-mediatek@lists.infradead.org, Oleg Nesterov , Dan Williams , linux-arm-kernel@lists.infradead.org, Christophe Leroy , Tony Luck , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Miles Chen , Mike Rapoport , James Morse , Souptick Joarder , Johannes Weiner , Martin Schwidefsky , Andrew Morton , linuxppc-dev@lists.ozlabs.org, Greg Hackmann MIME-Version: 1.0 Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+patchwork-linux-mediatek=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP I was recently going over all users of PG_reserved. Short story: it is difficult and sometimes not really clear if setting/checking for PG_reserved is only a relict from the past. Easy to break things. I guess I know have a pretty good idea wh things are like that nowadays and how they evolved. I had way more cleanups in this series inititally, but some architectures take PG_reserved as a way to apply a different caching strategy (for MMIO pages). So I decided to only include the most obvious changes (that are less likely to break something). So the big chunk of manual SetPageReserved users are MMIO/DMA related things on device buffers. Most notably, for device memory we will hopefully soon stop setting PG_reserved. The the documentation has to be updated. RFC -> V1: - Add more details to "mm: better document PG_reserved" - Add "arm64: kdump: No need to mark crashkernel pages manually PG_reserved" - Add "ia64: perfmon: Don't mark buffer pages as PG_reserved" - Added ACKs David Hildenbrand (9): agp: efficeon: no need to set PG_reserved on GATT tables s390/vdso: don't clear PG_reserved powerpc/vdso: don't clear PG_reserved riscv/vdso: don't clear PG_reserved m68k/mm: use __ClearPageReserved() arm64: kexec: no need to ClearPageReserved() arm64: kdump: No need to mark crashkernel pages manually PG_reserved ia64: perfmon: Don't mark buffer pages as PG_reserved mm: better document PG_reserved arch/arm64/kernel/machine_kexec.c | 3 +- arch/arm64/mm/init.c | 27 -------------- arch/ia64/kernel/perfmon.c | 59 +++---------------------------- arch/m68k/mm/memory.c | 2 +- arch/powerpc/kernel/vdso.c | 2 -- arch/riscv/kernel/vdso.c | 1 - arch/s390/kernel/vdso.c | 2 -- drivers/char/agp/efficeon-agp.c | 2 -- include/linux/page-flags.h | 33 +++++++++++++++-- 9 files changed, 37 insertions(+), 94 deletions(-)