Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754899AbZCRTqV (ORCPT ); Wed, 18 Mar 2009 15:46:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752095AbZCRTqJ (ORCPT ); Wed, 18 Mar 2009 15:46:09 -0400 Received: from gir.skynet.ie ([193.1.99.77]:33379 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751069AbZCRTqI (ORCPT ); Wed, 18 Mar 2009 15:46:08 -0400 Date: Wed, 18 Mar 2009 19:46:04 +0000 From: Mel Gorman To: Christoph Lameter Cc: Linux Memory Management List , Pekka Enberg , Rik van Riel , KOSAKI Motohiro , Johannes Weiner , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin , Peter Zijlstra Subject: Re: [PATCH 24/27] Convert gfp_zone() to use a table of precalculated values Message-ID: <20090318194604.GD24462@csn.ul.ie> References: <1237226020-14057-1-git-send-email-mel@csn.ul.ie> <1237226020-14057-25-git-send-email-mel@csn.ul.ie> <20090318135222.GA4629@csn.ul.ie> <20090318153508.GA24462@csn.ul.ie> <20090318181717.GC24462@csn.ul.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1433 Lines: 29 On Wed, Mar 18, 2009 at 03:07:48PM -0400, Christoph Lameter wrote: > On Wed, 18 Mar 2009, Mel Gorman wrote: > > > Thanks.At a quick glance, it looks ok but I haven't tested it. As the intention > > was to get one pass of patches that are not controversial and are "obvious", > > I have dropped my version of the gfp_zone patch and the subsequent flag > > cleanup and will revisit it after the first lot of patches has been dealt > > with. I'm testing again with the remaining patches. > > This fixes buggy behavior of gfp_zone so it would deserve a higher > priority. > It is buggy behaviour in response to a flag combination that makes no sense which arguably is a buggy caller. Now that I get to think about it a bit more, you can't define a const table in a header. If it's declared extern, then the compiler doesn't know what the constant value is so it can't generate better code. At best, you end up with equivalent code to what my patch did in the first place except __GFP_DMA32|__GFP_HIGHMEM will return ZONE_NORMAL. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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/