From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756549AbdD1HlK (ORCPT ); Fri, 28 Apr 2017 03:41:10 -0400 Received: from mx2.suse.de ([195.135.220.15]:39970 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750861AbdD1Hke (ORCPT ); Fri, 28 Apr 2017 03:40:34 -0400 Date: Fri, 28 Apr 2017 09:40:29 +0200 From: Michal Hocko To: Igor Stoppa Cc: namhyung@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] Remove hardcoding of ___GFP_xxx bitmasks Message-ID: <20170428074028.GF8143@dhcp22.suse.cz> References: <20170426133549.22603-1-igor.stoppa@huawei.com> <20170426133549.22603-2-igor.stoppa@huawei.com> <20170426144750.GH12504@dhcp22.suse.cz> <20170427134158.GI4706@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 27-04-17 17:06:05, Igor Stoppa wrote: > > > On 27/04/17 16:41, Michal Hocko wrote: > > On Wed 26-04-17 18:29:08, Igor Stoppa wrote: > > [...] > >> If you prefer to have this patch only as part of the larger patchset, > >> I'm also fine with it. > > > > I agree that the situation is not ideal. If a larger set of changes > > would benefit from this change then it would clearly add arguments... > > Ok, then I'll send it out as part of the larger RFC set. > > > >> Also, if you could reply to [1], that would be greatly appreciated. > > > > I will try to get to it but from a quick glance, yet-another-zone will > > hit a lot of opposition... > > The most basic questions, that I hope can be answered with Yes/No =) are: > > - should a new zone be added after DMA32? > > - should I try hard to keep the mask fitting a 32bit word - at least for > hose who do not use the new zone - or is it ok to just stretch it to 64 > bits? Do not add a new zone, really. What you seem to be looking for is an allocator on top of the page/memblock allocator which does write protection on top. I understand that you would like to avoid object management duplication but I am not really sure how much you can re-use what slab allocators do already, anyway. I will respond to the original thread to not mix things together. -- Michal Hocko SUSE Labs