Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764915AbZLQUmh (ORCPT ); Thu, 17 Dec 2009 15:42:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762699AbZLQUme (ORCPT ); Thu, 17 Dec 2009 15:42:34 -0500 Received: from nlpi157.sbcis.sbc.com ([207.115.36.171]:42533 "EHLO nlpi157.prodigy.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759930AbZLQUmd (ORCPT ); Thu, 17 Dec 2009 15:42:33 -0500 Date: Thu, 17 Dec 2009 14:42:03 -0600 (CST) From: Christoph Lameter X-X-Sender: cl@router.home To: Peter Zijlstra cc: Andi Kleen , "Paul E. McKenney" , KAMEZAWA Hiroyuki , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , "mingo@elte.hu" , minchan.kim@gmail.com Subject: Re: [mm][RFC][PATCH 0/11] mm accessor updates. In-Reply-To: <1261080855.27920.807.camel@laptop> Message-ID: References: <20091216191312.f4655dac.kamezawa.hiroyu@jp.fujitsu.com> <20091216102806.GC15031@basil.fritz.box> <20091216193109.778b881b.kamezawa.hiroyu@jp.fujitsu.com> <1261004224.21028.500.camel@laptop> <20091217084046.GA9804@basil.fritz.box> <1261039534.27920.67.camel@laptop> <20091217085430.GG9804@basil.fritz.box> <20091217144551.GA6819@linux.vnet.ibm.com> <20091217175338.GL9804@basil.fritz.box> <20091217190804.GB6788@linux.vnet.ibm.com> <20091217195530.GM9804@basil.fritz.box> <1261080855.27920.807.camel@laptop> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 861 Lines: 21 On Thu, 17 Dec 2009, Peter Zijlstra wrote: > > That is why I think that the accessors are a good first step. > > They're not, they're daft, they operate on a global resource mm_struct, > that's the whole problem, giving it a different name isn't going to > solve anything. It is not about naming. The accessors hide the locking mechanism for mmap_sem. Then you can change the locking in a central place. The locking may even become configurable later. Maybe an embedded solution will want the existing scheme but dual quad socket may want a distributed reference counter to avoid bouncing cachelines on faults. -- 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/