Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754920Ab0DUOQy (ORCPT ); Wed, 21 Apr 2010 10:16:54 -0400 Received: from nlpi157.sbcis.sbc.com ([207.115.36.171]:56846 "EHLO nlpi157.prodigy.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754840Ab0DUOQx (ORCPT ); Wed, 21 Apr 2010 10:16:53 -0400 Date: Wed, 21 Apr 2010 09:15:52 -0500 (CDT) From: Christoph Lameter X-X-Sender: cl@router.home To: Mel Gorman cc: Tejun Heo , 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 In-Reply-To: <20100420150522.GG19264@csn.ul.ie> Message-ID: References: <4BC6CB30.7030308@kernel.org> <4BC6E581.1000604@kernel.org> <4BC6FBC8.9090204@kernel.org> <1271606079.2100.159.camel@barrios-desktop> <4BCCD8BD.1020307@kernel.org> <20100420150522.GG19264@csn.ul.ie> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 608 Lines: 15 On Tue, 20 Apr 2010, Mel Gorman wrote: > 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. We can avoid alloc_pages_exact_node() by making all callers of alloc_pages_node() never use -1. -1 is ambiguous and only rarely will a caller pass that to alloc_pages_node(). -- 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/