Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932124AbZCPSDe (ORCPT ); Mon, 16 Mar 2009 14:03:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760762AbZCPRz4 (ORCPT ); Mon, 16 Mar 2009 13:55:56 -0400 Received: from smtp.ultrahosting.com ([74.213.174.254]:45955 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761242AbZCPRzz (ORCPT ); Mon, 16 Mar 2009 13:55:55 -0400 Date: Mon, 16 Mar 2009 12:31:44 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@qirst.com To: Mel Gorman 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 30/35] Skip the PCP list search by counting the order and type of pages on list In-Reply-To: <1237196790-7268-31-git-send-email-mel@csn.ul.ie> Message-ID: References: <1237196790-7268-1-git-send-email-mel@csn.ul.ie> <1237196790-7268-31-git-send-email-mel@csn.ul.ie> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) 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: 626 Lines: 19 On Mon, 16 Mar 2009, Mel Gorman wrote: > > struct per_cpu_pages { > - int count; /* number of pages in the list */ > + /* The total number of pages on the PCP lists */ > + int count; > + > + /* Count of each migratetype and order */ > + u8 mocount[MIGRATE_PCPTYPES][PAGE_ALLOC_COSTLY_ORDER+1]; What about overflow? You could have more than 255 pages of a given type in a pcp. -- 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/