From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759340AbZBEKOn (ORCPT ); Thu, 5 Feb 2009 05:14:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755369AbZBEKOe (ORCPT ); Thu, 5 Feb 2009 05:14:34 -0500 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:42391 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1755165AbZBEKOd (ORCPT ); Thu, 5 Feb 2009 05:14:33 -0500 Date: Thu, 05 Feb 2009 02:14:29 -0800 (PST) Message-Id: <20090205.021429.170975463.davem@davemloft.net> To: mel@csn.ul.ie Cc: kamezawa.hiroyu@jp.fujitsu.com, heiko.carstens@de.ibm.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org Subject: Re: HOLES_IN_ZONE... From: David Miller In-Reply-To: <20090205101023.GD26878@csn.ul.ie> References: <20090204.222651.26527737.davem@davemloft.net> <20090205101023.GD26878@csn.ul.ie> X-Mailer: Mew version 6.1 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mel Gorman Date: Thu, 5 Feb 2009 10:10:23 +0000 > On Wed, Feb 04, 2009 at 10:26:51PM -0800, David Miller wrote: > > As a suggestion, it would have been a lot more pleasant if the code > > validated this requirement (in the !HOLES_IN_ZONE case) at boot time > > instead of after 2 hours of stress testing :-( > > > > Nice maybe, but we'd take a hit on pfn_valid_within() which goes from > being compiled-away on architectures that don't need it to being > a read of a shared cacheline and a branch. I said at boot time Mel, not in the fast paths. Meaning, we'd check it after all the available ranges get registered and tossed into the free page lists. Anyways, it appears we have a fix already, read the rest of the thread.