From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id DE6236B004D for ; Fri, 6 Nov 2009 12:44:46 -0500 (EST) Date: Fri, 6 Nov 2009 18:44:39 +0100 From: Andi Kleen 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: Sender: owner-linux-mm@kvack.org 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" List-ID: 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org