Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750981AbaKYOdc (ORCPT ); Tue, 25 Nov 2014 09:33:32 -0500 Received: from mta-out1.inet.fi ([62.71.2.203]:57624 "EHLO kirsi1.inet.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750726AbaKYOdb (ORCPT ); Tue, 25 Nov 2014 09:33:31 -0500 Date: Tue, 25 Nov 2014 16:32:19 +0200 From: "Kirill A. Shutemov" To: David Rientjes Cc: Jianyu Zhan , akpm@linux-foundation.org, mgorman@suse.de, riel@redhat.com, sasha.levin@oracle.com, n-horiguchi@ah.jp.nec.com, andriy.shevchenko@linux.intel.com, hannes@cmpxchg.org, vdavydov@parallels.com, fabf@skynet.be, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jianyu Zhan Subject: Re: [PATCH] mm, gfp: escalatedly define GFP_HIGHUSER and GFP_HIGHUSER_MOVABLE Message-ID: <20141125143219.GC11841@node.dhcp.inet.fi> References: <1416847427-2550-1-git-send-email-nasa4836@gmail.com> <20141124190127.GA5027@node.dhcp.inet.fi> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 24, 2014 at 01:35:00PM -0800, David Rientjes wrote: > On Mon, 24 Nov 2014, Kirill A. Shutemov wrote: > > > But I would prefer to have GPF_HIGHUSER movable by default and > > GFP_HIGHUSER_UNMOVABLE to opt out. > > > > Sounds like a separate patch. There are few questions before preparing patch: 1. Compatibility: some code which is not yet in tree can rely on non-movable behaviour of GFP_HIGHUSER. How would we handle this? Should we invent new name for the movable GFP_HIGHUSER? 2. Should GFP_USER be movable too? And the same compatibility question here. 3. Do we need a separate define for non-movable GPF_HIGHUSER or caller should use something like GPF_HIGHUSER & ~__GFP_MOVABLE? 4. Is there a gain, taking into account questions above? -- Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/