From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 28 May 2002 08:54:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 28 May 2002 08:54:38 -0400 Received: from e21.nc.us.ibm.com ([32.97.136.227]:24252 "EHLO e21.nc.us.ibm.com") by vger.kernel.org with ESMTP id ; Tue, 28 May 2002 08:54:38 -0400 Date: Tue, 28 May 2002 18:28:06 +0530 From: Dipankar Sarma To: "David S. Miller" , Linus Torvalds Cc: linux-kernel@vger.kernel.org, Paul McKenney , Andrea Arcangeli Subject: Re: 8-CPU (SMP) #s for lockfree rtcache Message-ID: <20020528182806.A21303@in.ibm.com> Reply-To: dipankar@in.ibm.com In-Reply-To: <20020528171104.D19734@in.ibm.com> <20020528.042514.92633856.davem@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 28, 2002 at 04:25:14AM -0700, David S. Miller wrote: > From: Dipankar Sarma > Date: Tue, 28 May 2002 17:11:04 +0530 > > Here are the results in terms of profile counts in > ip_route_output_key() - gc stands for neighbor table garbage > collection adjustment and u2000 stands for 2ms packet > rate delay. All measurements where done based on 2.5.3 kernel. > > Thanks, I am convinced RCU is the way to go. > > Once the generic RCU bits are in the 2.5.x tree, feel free to > send me your ipv4 routing cache changes. Well, the last time RCU was discussed, Linus said that he would like to see someplace where RCU clearly helps. Linus, would you consider this to be such a case and consider including the rcu_poll patch from aa series of kernels ? It has been a part of aa kernels for quite a while now. The latest RCU patches support preemption and AFAICS, new module unloading and cpu hotplug frameworks can use the RCU synchronize_kernel() interface. Or atleast, we can perhaps discuss RCU and see if there are potential issues that have not been disected so far. Thanks -- Dipankar Sarma http://lse.sourceforge.net Linux Technology Center, IBM Software Lab, Bangalore, India.