From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934671AbXGWXRk (ORCPT ); Mon, 23 Jul 2007 19:17:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934069AbXGWXRP (ORCPT ); Mon, 23 Jul 2007 19:17:15 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:41083 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933955AbXGWXRO (ORCPT ); Mon, 23 Jul 2007 19:17:14 -0400 Date: Mon, 23 Jul 2007 16:17:13 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Peter Zijlstra cc: Mel Gorman , Andrew Morton , Linus Torvalds , linux-kernel , Daniel Phillips , linux-mm Subject: Re: [PATCH] add __GFP_ZERO to GFP_LEVEL_MASK In-Reply-To: <1185190711.8197.15.camel@twins> Message-ID: References: <1185185020.8197.11.camel@twins> <20070723112143.GB19437@skynet.ie> <1185190711.8197.15.camel@twins> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 23 Jul 2007, Peter Zijlstra wrote: > --- > Daniel recently spotted that __GFP_ZERO is not (and has never been) > part of GFP_LEVEL_MASK. I could not find a reason for this in the > original patch: 3977971c7f09ce08ed1b8d7a67b2098eb732e4cd in the -bk > tree. > > This of course is in stark contradiction with the comment accompanying > GFP_LEVEL_MASK. NACK. The effect that this patch will have is that __GFP_ZERO is passed through to the page allocator which will needlessly zero pages. GFP_LEVEL_MASK is used to filter out the flags that are to be passed to the page allocator. __GFP_ZERO is not passed on but handled by the slab allocators.