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=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 066AAC433E0 for ; Mon, 6 Jul 2020 11:22:55 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C51422073E for ; Mon, 6 Jul 2020 11:22:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="KSqrSn4m" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C51422073E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xSqjb5C0pfbPETWqsqgtsRtbxAMLOrmzqoWfD29mRlo=; b=KSqrSn4mO9A9+I+dbddeEdDS/ fk+pG1fr8QXqMXJ4PSjLrHCgQ4VZ39e0K334VimqnJc2maZDtfMDtppa1Ch/nDtsNpNzq3yA9Td2u o++cZrk8tYGuhI5RA+PX1ecdD71BrrAnKWxTaAQviEFcz2apCi6U2QDo0zuY8K1+4fpiiVAqQYPAa VcsQjV9MnliG2VLWgwLGId+ebZMYB+IVllGDemoMrDtGmryQ9jaxTjSNEIieGkI2xBTGq4Aq3jP9Z ZyASTfhmTvcdzXe7vtfcbPQcdEwGLxqqrViwaX2MijckwQILTEzZ3P6nwFtTqdX5v0jl+uaIrif/U LW5CGKiYw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jsPBg-00075Q-71; Mon, 06 Jul 2020 11:21:28 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jsPBe-00074e-2M for linux-arm-kernel@lists.infradead.org; Mon, 06 Jul 2020 11:21:26 +0000 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 36A2EC0A; Mon, 6 Jul 2020 04:21:21 -0700 (PDT) Received: from gaia (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7420D3F68F; Mon, 6 Jul 2020 04:21:19 -0700 (PDT) Date: Mon, 6 Jul 2020 12:21:13 +0100 From: Catalin Marinas To: David Hildenbrand Subject: Re: [PATCH v6 06/26] mm: Add PG_arch_2 page flag Message-ID: <20200706112057.GA6432@gaia> References: <20200703153718.16973-1-catalin.marinas@arm.com> <20200703153718.16973-7-catalin.marinas@arm.com> <27fe044a-8315-5394-575e-8f763696b0cd@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <27fe044a-8315-5394-575e-8f763696b0cd@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200706_072126_188626_069BAE43 X-CRM114-Status: GOOD ( 12.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Szabolcs Nagy , Andrey Konovalov , Kevin Brodsky , Steven Price , Peter Collingbourne , linux-mm@kvack.org, Andrew Morton , Vincenzo Frascino , Will Deacon , Dave P Martin , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jul 06, 2020 at 10:24:04AM +0200, David Hildenbrand wrote: > On 03.07.20 17:36, Catalin Marinas wrote: > > diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h > > index 6be1aa559b1e..276140c94f4a 100644 > > --- a/include/linux/page-flags.h > > +++ b/include/linux/page-flags.h > > @@ -135,6 +135,9 @@ enum pageflags { > > #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT) > > PG_young, > > PG_idle, > > +#endif > > +#ifdef CONFIG_64BIT > > + PG_arch_2, > > #endif > > __NR_PAGEFLAGS, > > People are usually *very* picky when it comes to new page flags. It > somewhat concerns me that we bump up __NR_PAGEFLAGS for any 64bit arch. > That feels wrong. It was guarded by a specific config option initially but the comments suggested that it could be dropped for 64-bit architectures: https://lore.kernel.org/linux-arm-kernel/20200624113307.6165b3db2404c9d37b870a90@linux-foundation.org/ The page flags is indeed a pretty limited resource as it also includes the sparsemem section, node and zone fields. However, on 64-bit this should be fine (the sparsemem section is gone with vmemmap support). -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel