Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030291AbWALFg3 (ORCPT ); Thu, 12 Jan 2006 00:36:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030294AbWALFg2 (ORCPT ); Thu, 12 Jan 2006 00:36:28 -0500 Received: from e4.ny.us.ibm.com ([32.97.182.144]:7836 "EHLO e4.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1030291AbWALFg2 (ORCPT ); Thu, 12 Jan 2006 00:36:28 -0500 Subject: Re: [Lse-tech] Re: [ckrm-tech] Re: [PATCH 00/01] Move Exit Connectors From: Matt Helsley To: Keith Owens Cc: John Hesterberg , Jes Sorensen , Shailabh Nagar , Andrew Morton , Jay Lan , LKML , elsa-devel@lists.sourceforge.net, lse-tech@lists.sourceforge.net, CKRM-Tech , Paul Jackson , Erik Jacobson , Jack Steiner In-Reply-To: <8699.1137036592@kao2.melbourne.sgi.com> References: <8699.1137036592@kao2.melbourne.sgi.com> Content-Type: text/plain Date: Wed, 11 Jan 2006 21:26:08 -0800 Message-Id: <1137043569.6673.156.camel@stark> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1250 Lines: 30 On Thu, 2006-01-12 at 14:29 +1100, Keith Owens wrote: > John Hesterberg (on Wed, 11 Jan 2006 15:39:10 -0600) wrote: > >On Wed, Jan 11, 2006 at 01:02:10PM -0800, Matt Helsley wrote: > >> Have you looked at Alan Stern's notifier chain fix patch? Could that be > >> used in task_notify? > > > >I have two concerns about an all-tasks notification interface. > >First, we want this to scale, so don't want more global locks. > >One unique part of the task notify is that it doesn't use locks. > > Neither does Alan Stern's atomic notifier chain. Indeed it cannot use > locks, because the atomic notifier chains can be called from anywhere, > including non maskable interrupts. The downside is that Alan's atomic > notifier chains require RCU. > > An alternative patch that requires no locks and does not even require > RCU is in http://marc.theaimsgroup.com/?l=linux-kernel&m=113392370322545&w=2 > Interesting. Might the 'inuse' flags suffer from bouncing due to false sharing? Cheers, -Matt Helsley - 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/