From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 31 Aug 2002 17:20:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 31 Aug 2002 17:20:35 -0400 Received: from dsl-213-023-043-117.arcor-ip.net ([213.23.43.117]:49386 "EHLO starship") by vger.kernel.org with ESMTP id ; Sat, 31 Aug 2002 17:20:34 -0400 Content-Type: text/plain; charset=US-ASCII From: Daniel Phillips To: Andrew Morton Subject: Re: [RFC] [PATCH] Include LRU in page count Date: Sat, 31 Aug 2002 23:05:02 +0200 X-Mailer: KMail [version 1.3.2] Cc: Christian Ehrhardt , Linus Torvalds , Marcelo Tosatti , linux-kernel@vger.kernel.org References: <3D644C70.6D100EA5@zip.com.au> <3D712682.66E2D3B2@zip.com.au> In-Reply-To: <3D712682.66E2D3B2@zip.com.au> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Message-Id: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 31 August 2002 22:26, Andrew Morton wrote: > Daniel Phillips wrote: > > Manfred suggested an approach to de-racing this race using > > atomic_dec_and_lock, which needs to be compared to the current approach. > > Could simplify things, but not all architectures have an optimised > version. So ia64, mips, parisc and s390 would end up taking > the lru lock on every page_cache_release. As far as implementing it goes, some instances of page_cache_release are already under the lru lock and would need an alternative, non-locking version. The current patch seems satisfactory performance-wise and if it's also raceless as it's supposed to be, it gives us something that works, and we can evaluate alternatives at our leisure. Right now I'm afraid we have something that just works most of the time. I think we're getting to the point where this needs to get some heavy beating up, to see what happens. -- Daniel