From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3tHz1y5wgJzDqV5 for ; Tue, 15 Nov 2016 18:05:58 +1100 (AEDT) Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uAF74nsR118117 for ; Tue, 15 Nov 2016 02:05:56 -0500 Received: from e17.ny.us.ibm.com (e17.ny.us.ibm.com [129.33.205.207]) by mx0a-001b2d01.pphosted.com with ESMTP id 26qv3fv10u-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 15 Nov 2016 02:05:56 -0500 Received: from localhost by e17.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 15 Nov 2016 02:05:55 -0500 From: "Aneesh Kumar K.V" To: Reza Arbab , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Andrew Morton , Rob Herring , Frank Rowand , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, devicetree@vger.kernel.org, Bharata B Rao , Nathan Fontenot , Stewart Smith , Alistair Popple , Balbir Singh , linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 2/5] mm: remove x86-only restriction of movable_node In-Reply-To: <1479160961-25840-3-git-send-email-arbab@linux.vnet.ibm.com> References: <1479160961-25840-1-git-send-email-arbab@linux.vnet.ibm.com> <1479160961-25840-3-git-send-email-arbab@linux.vnet.ibm.com> Date: Tue, 15 Nov 2016 12:35:42 +0530 MIME-Version: 1.0 Content-Type: text/plain Message-Id: <87lgwlb4u1.fsf@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reza Arbab writes: > In commit c5320926e370 ("mem-hotplug: introduce movable_node boot > option"), the memblock allocation direction is changed to bottom-up and > then back to top-down like this: > > 1. memblock_set_bottom_up(true), called by cmdline_parse_movable_node(). > 2. memblock_set_bottom_up(false), called by x86's numa_init(). > > Even though (1) occurs in generic mm code, it is wrapped by #ifdef > CONFIG_MOVABLE_NODE, which depends on X86_64. > > This means that when we extend CONFIG_MOVABLE_NODE to non-x86 arches, > things will be unbalanced. (1) will happen for them, but (2) will not. > > This toggle was added in the first place because x86 has a delay between > adding memblocks and marking them as hotpluggable. Since other arches do > this marking either immediately or not at all, they do not require the > bottom-up toggle. > > So, resolve things by moving (1) from cmdline_parse_movable_node() to > x86's setup_arch(), immediately after the movable_node parameter has > been parsed. Considering that we now can mark memblock hotpluggable, do we need to enable the bottom up allocation for ppc64 also ? > > Signed-off-by: Reza Arbab > --- > Documentation/kernel-parameters.txt | 2 +- > arch/x86/kernel/setup.c | 24 ++++++++++++++++++++++++ -aneesh