From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by kanga.kvack.org (Postfix) with ESMTP id 47C276B1A39 for ; Mon, 19 Nov 2018 05:20:34 -0500 (EST) Received: by mail-ed1-f72.google.com with SMTP id c53so6710339edc.9 for ; Mon, 19 Nov 2018 02:20:34 -0800 (PST) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id l15-v6si1554327ejc.183.2018.11.19.02.20.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Nov 2018 02:20:32 -0800 (PST) Date: Mon, 19 Nov 2018 11:20:30 +0100 From: Michal Hocko Subject: Re: [PATCH] mm, page_alloc: fix calculation of pgdat->nr_zones Message-ID: <20181119102030.GD22247@dhcp22.suse.cz> References: <20181117022022.9956-1-richard.weiyang@gmail.com> <1542622061.3002.6.camel@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1542622061.3002.6.camel@suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: osalvador Cc: Wei Yang , akpm@linux-foundation.org, dave.hansen@intel.com, linux-mm@kvack.org On Mon 19-11-18 11:07:41, osalvador wrote: [...] > One thing I was wondering is that if we also should re-adjust it when a > zone gets emptied during offlining memory. > I checked, and whenever we work wirh pgdat->nr_zones we seem to check > if the zone is populated in order to work with it. > But still, I wonder if we should re-adjust it. I would rather not because we are not really deallocating zones and once you want to shrink it you have to linearize all the loops depending on it. -- Michal Hocko SUSE Labs