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=-2.5 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 565DDC468C6 for ; Thu, 19 Jul 2018 14:03:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFC7220673 for ; Thu, 19 Jul 2018 14:03:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EFC7220673 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731747AbeGSOqb (ORCPT ); Thu, 19 Jul 2018 10:46:31 -0400 Received: from mx2.suse.de ([195.135.220.15]:60718 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727575AbeGSOqb (ORCPT ); Thu, 19 Jul 2018 10:46:31 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 68E08ADB0; Thu, 19 Jul 2018 14:03:10 +0000 (UTC) Date: Thu, 19 Jul 2018 16:03:08 +0200 From: Michal Hocko To: Oscar Salvador Cc: akpm@linux-foundation.org, pasha.tatashin@oracle.com, vbabka@suse.cz, aaron.lu@intel.com, iamjoonsoo.kim@lge.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Oscar Salvador Subject: Re: [PATCH v2 5/5] mm/page_alloc: Only call pgdat_set_deferred_range when the system boots Message-ID: <20180719140308.GG7193@dhcp22.suse.cz> References: <20180719132740.32743-1-osalvador@techadventures.net> <20180719132740.32743-6-osalvador@techadventures.net> <20180719134622.GE7193@dhcp22.suse.cz> <20180719135859.GA10988@techadventures.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180719135859.GA10988@techadventures.net> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 19-07-18 15:58:59, Oscar Salvador wrote: > On Thu, Jul 19, 2018 at 03:46:22PM +0200, Michal Hocko wrote: > > On Thu 19-07-18 15:27:40, osalvador@techadventures.net wrote: > > > From: Oscar Salvador > > > > > > We should only care about deferred initialization when booting. > > > > Again why is this worth doing? > > Well, it is not a big win if that is what you meant. > > Those two fields are only being used when dealing with deferred pages, > which only happens at boot time. > > If later on, free_area_init_node gets called from memhotplug code, > we will also set the fields, although they will not be used. > > Is this a problem? No, but I think it is more clear from the code if we > see when this is called. > So I would say it was only for code consistency. Then put it to the changelog. > If you think this this is not worth, I am ok with dropping it. I am not really sure. I am not a big fan of SYSTEM_BOOTING global thingy so I would rather not spread its usage. -- Michal Hocko SUSE Labs