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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1171BC433DB for ; Fri, 12 Feb 2021 10:37:57 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id AD50F64E6B for ; Fri, 12 Feb 2021 10:37:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD50F64E6B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 42B798D0041; Fri, 12 Feb 2021 05:37:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 402098D0015; Fri, 12 Feb 2021 05:37:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 31A9C8D0041; Fri, 12 Feb 2021 05:37:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0060.hostedemail.com [216.40.44.60]) by kanga.kvack.org (Postfix) with ESMTP id 1DBAE8D0015 for ; Fri, 12 Feb 2021 05:37:56 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id E10F752AA for ; Fri, 12 Feb 2021 10:37:55 +0000 (UTC) X-FDA: 77809265310.24.unit62_400976727620 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin24.hostedemail.com (Postfix) with ESMTP id C2AFD1A4A0 for ; Fri, 12 Feb 2021 10:37:55 +0000 (UTC) X-HE-Tag: unit62_400976727620 X-Filterd-Recvd-Size: 3854 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Fri, 12 Feb 2021 10:37:55 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1613126274; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=CEZkfyq7c0HGgwSW7w7T0gscG26D0F30UkRDuR38AsM=; b=dWPfd+mQe25awJB+EwHVl+CPT6wfHtjfT4jfw4ayvaNY+WkkW1/DRjat0T5oGQUVK6Xidl ehyPrjAWVV4C7MI+WRShrEF5eOQXUwNWDXr4cAGvg5BixsppQUF0Ui7KnbyW37avrYllQj teHwKiCW+k6lxA59/cJR50DLxKPZX18= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 36AE9AD62; Fri, 12 Feb 2021 10:37:54 +0000 (UTC) Date: Fri, 12 Feb 2021 11:37:53 +0100 From: Michal Hocko To: David Hildenbrand Cc: Mike Rapoport , Andrew Morton , Andrea Arcangeli , Baoquan He , Borislav Petkov , Chris Wilson , "H. Peter Anvin" , Ingo Molnar , Linus Torvalds , =?utf-8?Q?=C5=81ukasz?= Majczak , Mel Gorman , Mike Rapoport , Qian Cai , "Sarvela, Tomi P" , Thomas Gleixner , Vlastimil Babka , linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v5 1/1] mm: refactor initialization of struct page for holes in memory layout Message-ID: References: <20210208110820.6269-1-rppt@kernel.org> <5dccbc93-f260-7f14-23bc-6dee2dff6c13@redhat.com> <1523f1a6-41be-1fc7-08b9-b777a5b4ef24@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1523f1a6-41be-1fc7-08b9-b777a5b4ef24@redhat.com> 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 Fri 12-02-21 11:16:28, David Hildenbrand wrote: > On 12.02.21 11:11, Michal Hocko wrote: > > On Fri 12-02-21 10:56:19, David Hildenbrand wrote: > > > On 12.02.21 10:55, David Hildenbrand wrote: > > > > On 08.02.21 12:08, Mike Rapoport wrote: > > [...] > > > > > @@ -6519,8 +6581,19 @@ void __init get_pfn_range_for_nid(unsigned int nid, > > > > > *end_pfn = max(*end_pfn, this_end_pfn); > > > > > } > > > > > - if (*start_pfn == -1UL) > > > > > + if (*start_pfn == -1UL) { > > > > > *start_pfn = 0; > > > > > + return; > > > > > + } > > > > > + > > > > > +#ifdef CONFIG_SPARSEMEM > > > > > + /* > > > > > + * Sections in the memory map may not match actual populated > > > > > + * memory, extend the node span to cover the entire section. > > > > > + */ > > > > > + *start_pfn = round_down(*start_pfn, PAGES_PER_SECTION); > > > > > + *end_pfn = round_up(*end_pfn, PAGES_PER_SECTION); > > > > > > > > Does that mean that we might create overlapping zones when one node > > > > > > s/overlapping zones/overlapping nodes/ > > > > I didn't get to review the patch yet. Just wanted to note that we can > > interleave nodes/zone. Or what kind of concern do you have in mind? > > I know that we can have it after boot, when hotplugging memory. How about > during boot? I have seen systems where NUMA nodes are interleaved. > For example, which node will a PFN then actually be assigned to? I would have to double check all the details but I do remember there was a non trivial work to handle those systems. -- Michal Hocko SUSE Labs