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=HEADER_FROM_DIFFERENT_DOMAINS, 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 48DADC282C3 for ; Tue, 22 Jan 2019 23:52:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F38120684 for ; Tue, 22 Jan 2019 23:52:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727004AbfAVXwN (ORCPT ); Tue, 22 Jan 2019 18:52:13 -0500 Received: from mx1.redhat.com ([209.132.183.28]:38806 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726175AbfAVXwN (ORCPT ); Tue, 22 Jan 2019 18:52:13 -0500 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 mx1.redhat.com (Postfix) with ESMTPS id A2DB79FDCF; Tue, 22 Jan 2019 23:52:12 +0000 (UTC) Received: from redhat.com (ovpn-124-136.rdu2.redhat.com [10.10.124.136]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DD87C100194A; Tue, 22 Jan 2019 23:52:11 +0000 (UTC) Date: Tue, 22 Jan 2019 18:52:07 -0500 From: Jerome Glisse To: Andi Kleen Cc: lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [LSF/MM TOPIC] Page flags, can we free up space ? Message-ID: <20190122235207.GC4747@redhat.com> References: <20190122201744.GA3939@redhat.com> <87tvi074gg.fsf@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87tvi074gg.fsf@linux.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Tue, 22 Jan 2019 23:52:12 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 22, 2019 at 01:44:15PM -0800, Andi Kleen wrote: > Jerome Glisse writes: > > > > Right now this is more a temptative ie i do not know if i will succeed, > > in any case i can report on failure or success and discuss my finding to > > get people opinions on the matter. > > I would just stop putting node/zone number into the flags. These > could be all handled with a small perfect hash table, like the original > x86_64 port did, which should be quite cheap to look up. > Then there should be enough bits for everyone again. Definitly something i will look into, i was scare to remove those. Cheers, Jérôme