Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751776Ab0DTPFn (ORCPT ); Tue, 20 Apr 2010 11:05:43 -0400 Received: from gir.skynet.ie ([193.1.99.77]:55833 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751570Ab0DTPFm (ORCPT ); Tue, 20 Apr 2010 11:05:42 -0400 Date: Tue, 20 Apr 2010 16:05:22 +0100 From: Mel Gorman To: Tejun Heo Cc: Christoph Lameter , Minchan Kim , Andrew Morton , KAMEZAWA Hiroyuki , Bob Liu , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 2/6] change alloc function in pcpu_alloc_pages Message-ID: <20100420150522.GG19264@csn.ul.ie> References: <4BC6CB30.7030308@kernel.org> <4BC6E581.1000604@kernel.org> <4BC6FBC8.9090204@kernel.org> <1271606079.2100.159.camel@barrios-desktop> <4BCCD8BD.1020307@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <4BCCD8BD.1020307@kernel.org> 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: 1009 Lines: 24 On Tue, Apr 20, 2010 at 07:27:09AM +0900, Tejun Heo wrote: > Hello, Christoph. > > On 04/20/2010 02:38 AM, Christoph Lameter wrote: > > alloc_pages_exact_node results in more confusion because it does suggest > > that fallback to other nodes is not allowed. > > I can't see why alloc_pages_exact_node() exists at all. It's in the > mainline and if you look at the difference between alloc_pages_node() > and alloc_pages_exact_node(), it's almost silly. :-( > alloc_pages_exact_node() avoids a branch in a hot path that is checking for something the caller already knows. That's the reason it exists. -- 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/