From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992564AbXCBP6A (ORCPT ); Fri, 2 Mar 2007 10:58:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992550AbXCBP5e (ORCPT ); Fri, 2 Mar 2007 10:57:34 -0500 Received: from hellhawk.shadowen.org ([80.68.90.175]:1106 "EHLO hellhawk.shadowen.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992551AbXCBP5W (ORCPT ); Fri, 2 Mar 2007 10:57:22 -0500 Message-ID: <45E8495A.4080501@shadowen.org> Date: Fri, 02 Mar 2007 15:57:14 +0000 From: Andy Whitcroft User-Agent: Icedove 1.5.0.9 (X11/20061220) MIME-Version: 1.0 To: Christoph Lameter CC: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mel Gorman Subject: Re: [PATCH 2/5] lumpy: isolate_lru_pages wants to specifically take active or inactive pages References: In-Reply-To: X-Enigmail-Version: 0.94.2.0 OpenPGP: url=http://www.shadowen.org/~apw/public-key Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Christoph Lameter wrote: > On Tue, 27 Feb 2007, Andy Whitcroft wrote: > >> The caller of isolate_lru_pages specifically knows whether it wants >> to take either inactive or active pages. Currently we take the >> state of the LRU page at hand and use that to scan for matching >> pages in the order sized block. If that page is transiting we >> can scan for the wrong type. The caller knows what they want and >> should be telling us. Pass in the required active/inactive state >> and match against that. > > The page cannot be transiting since we hold the lru lock? As you say it should be gated by lru_lock and we should not expect to see pages with the wrong type on the list. I would swear that I was seeing pages on the wrong list there for a bit in testing and mistakenly thought they were in transition. A quick review at least says thats false. So I'll reinstate the BUG() and retest to see if I am smoking crack or there is a bigger bug out there. -apw