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=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 63E0AC433E0 for ; Tue, 16 Feb 2021 08:25:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2089A64E02 for ; Tue, 16 Feb 2021 08:25:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229676AbhBPIYg (ORCPT ); Tue, 16 Feb 2021 03:24:36 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:55020 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229833AbhBPIWP (ORCPT ); Tue, 16 Feb 2021 03:22:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613463646; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nXQZaXLCBgz8dc1mXq0vQ/pvFEf1q+06R2ew5QKUNfc=; b=aDzQBvxc0dRIJ/jMGmgUjhZJGR1gafsv8RT3LZCoaEL6mY5TgI3MWqCk/C12EhZiICaynl +bEnIrpKekj9TMYxTg6Q8qnOLL25rSXbkoHIvpYygm4qEO6psCExGic0W6BSKs48zmUNLR 68WUsjFowam3/0J45xHOd2zX0QXRPSc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-497-clV1UIxWNYudo5xffb8pPg-1; Tue, 16 Feb 2021 03:20:43 -0500 X-MC-Unique: clV1UIxWNYudo5xffb8pPg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 76555192D785; Tue, 16 Feb 2021 08:20:39 +0000 (UTC) Received: from [10.36.114.70] (ovpn-114-70.ams2.redhat.com [10.36.114.70]) by smtp.corp.redhat.com (Postfix) with ESMTP id 171BE10013DB; Tue, 16 Feb 2021 08:20:32 +0000 (UTC) Subject: Re: [External] Re: [PATCH v15 4/8] mm: hugetlb: alloc the vmemmap pages associated with each HugeTLB page To: Michal Hocko , Muchun Song Cc: Jonathan Corbet , Mike Kravetz , Thomas Gleixner , mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, dave.hansen@linux.intel.com, luto@kernel.org, Peter Zijlstra , viro@zeniv.linux.org.uk, Andrew Morton , paulmck@kernel.org, mchehab+huawei@kernel.org, pawan.kumar.gupta@linux.intel.com, Randy Dunlap , oneukum@suse.com, anshuman.khandual@arm.com, jroedel@suse.de, Mina Almasry , David Rientjes , Matthew Wilcox , Oscar Salvador , "Song Bao Hua (Barry Song)" , =?UTF-8?B?SE9SSUdVQ0hJIE5BT1lBKOWggOWPoyDnm7TkuZ8p?= , Joao Martins , Xiongchun duan , linux-doc@vger.kernel.org, LKML , Linux Memory Management List , linux-fsdevel References: From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <83ba1af6-7c11-3da7-eadb-020ca591bb56@redhat.com> Date: Tue, 16 Feb 2021 09:20:32 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >> If current >> node has no memory and other nodes have enough memory. >> We can fail to allocate vmemmap pages. But actually it is >> suitable to allocate vmemmap pages from other nodes. >> Right? > > Falling back to a different node would be very suboptimal because then > you would have vmemmap back by remote pages. We do not want that. ... and we even warn when this happens right now: mm/sparse-vmemmap.c:vmemmap_verify() -- Thanks, David / dhildenb