Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964902AbVIIPXJ (ORCPT ); Fri, 9 Sep 2005 11:23:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964913AbVIIPXJ (ORCPT ); Fri, 9 Sep 2005 11:23:09 -0400 Received: from smtp205.mail.sc5.yahoo.com ([216.136.129.95]:23651 "HELO smtp205.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S964902AbVIIPXI (ORCPT ); Fri, 9 Sep 2005 11:23:08 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=eYVDLdFVKGWTvt7Op/e7nRoynkCd6Zsj1X4Jz/xCdqW9jPxaQ4wFWh5zlf/MMeJFDiiT6cQ8joGP7p3FEcb0U32acULi5fKaJjHzKHLIeq80sghGS7OKleOzGwBFckxFso5khkAR7v4SKhpTg01Wo/pe0lbD7LOgY/ivJ1GD1s4= ; Message-ID: <4321A8EE.9080206@yahoo.com.au> Date: Sat, 10 Sep 2005 01:23:26 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.10) Gecko/20050802 Debian/1.7.10-1 X-Accept-Language: en MIME-Version: 1.0 To: Christoph Lameter CC: Linux Memory Management , linux-kernel Subject: Re: [PATCH 2.6.13] lockless pagecache 7/7 References: <4317F071.1070403@yahoo.com.au> <4317F0F9.1080602@yahoo.com.au> <4317F136.4040601@yahoo.com.au> <4317F17F.5050306@yahoo.com.au> <4317F1A2.8030605@yahoo.com.au> <4317F1BD.8060808@yahoo.com.au> <4317F1E2.7030608@yahoo.com.au> <4317F203.7060109@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1014 Lines: 27 Christoph Lameter wrote: > For Itanium (and I guess also for ppc64 and sparch64) the performance of > write_lock/unlock is the same as spin_lock/unlock. There is at least > one case where concurrent reads would be allowed without this patch. > Yep, I picked up another one that was easy to make lockless (I'll send out a new patchset soon), however the tagged lookup that was under read lock is changed to a spin lock. It shouldn't be too difficult to make the tag lookups (find_get_pages_tag) lockless, however I just haven't gotten around to looking at the write side of the tagging yet. When that is done, there should be no more read locks at all. Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - 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/