Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759529AbZKFRog (ORCPT ); Fri, 6 Nov 2009 12:44:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759395AbZKFRog (ORCPT ); Fri, 6 Nov 2009 12:44:36 -0500 Received: from one.firstfloor.org ([213.235.205.2]:42252 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758787AbZKFRof (ORCPT ); Fri, 6 Nov 2009 12:44:35 -0500 Date: Fri, 6 Nov 2009 18:44:39 +0100 From: Andi Kleen To: Christoph Lameter Cc: Andi Kleen , npiggin@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , Ingo Molnar , KAMEZAWA Hiroyuki , "hugh.dickins@tiscali.co.uk" Subject: Re: Subject: [RFC MM] mmap_sem scaling: Use mutex and percpu counter instead Message-ID: <20091106174439.GB819@basil.fritz.box> References: <87r5sc7kst.fsf@basil.nowhere.org> <20091106073946.GV31511@one.firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 776 Lines: 22 On Fri, Nov 06, 2009 at 12:08:54PM -0500, Christoph Lameter wrote: > On Fri, 6 Nov 2009, Andi Kleen wrote: > > > Yes but all the major calls still take mmap_sem, which is not ranged. > > But exactly that issue is addressed by this patch! Major calls = mmap, brk, etc. Only for page faults, not for anything that takes it for write. Anyways the better reader lock is a step in the right direction, but I have my doubts it's a good idea to make write really slow here. -Andi -- ak@linux.intel.com -- Speaking for myself only. -- 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/