From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755306AbaEAOft (ORCPT ); Thu, 1 May 2014 10:35:49 -0400 Received: from mga02.intel.com ([134.134.136.20]:55333 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755224AbaEAOfs (ORCPT ); Thu, 1 May 2014 10:35:48 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,965,1389772800"; d="scan'208";a="504321188" Message-ID: <53625BC3.3000804@intel.com> Date: Thu, 01 May 2014 07:35:47 -0700 From: Dave Hansen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Mel Gorman , Linux-MM , Linux-FSDevel CC: Johannes Weiner , Vlastimil Babka , Jan Kara , Michal Hocko , Hugh Dickins , Linux Kernel Subject: Re: [PATCH 11/17] mm: page_alloc: Use unsigned int for order in more places References: <1398933888-4940-1-git-send-email-mgorman@suse.de> <1398933888-4940-12-git-send-email-mgorman@suse.de> In-Reply-To: <1398933888-4940-12-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/01/2014 01:44 AM, Mel Gorman wrote: > X86 prefers the use of unsigned types for iterators and there is a > tendency to mix whether a signed or unsigned type if used for page > order. This converts a number of sites in mm/page_alloc.c to use > unsigned int for order where possible. Does this actually generate any different code? I'd actually expect something like 'order' to be one of the easiest things for the compiler to figure out an absolute range on.