From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752626AbZI1QJ6 (ORCPT ); Mon, 28 Sep 2009 12:09:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751822AbZI1QJ6 (ORCPT ); Mon, 28 Sep 2009 12:09:58 -0400 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:46093 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751726AbZI1QJ5 (ORCPT ); Mon, 28 Sep 2009 12:09:57 -0400 Date: Mon, 28 Sep 2009 09:09:44 -0700 From: Josh Triplett To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, dvhltc@us.ibm.com, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com Subject: Re: [PATCH tip/core/rcu 0/2] rcu: v2: more review feedback Message-ID: <20090928160943.GA16591@feather> References: <20090927064753.GA9394@linux.vnet.ibm.com> <20090928144551.GA20704@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090928144551.GA20704@linux.vnet.ibm.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 28, 2009 at 07:45:51AM -0700, Paul E. McKenney wrote: > This patchset applies the last of the review comments: > > o Whitespace fixes, updated comments, and code movement. > > o Improve an existing abstraction and introduce two additional > abstractions for traversing the rcu_node tree. > > Change since v1 (http://lkml.org/lkml/2009/9/27/17): > > o Update second patch's changelog > > Issues remaining: > > o I can force hangs given sufficient rcutorture testing in > conjunction with random CPU-hotplug operations. I am working > on a simpler interface between RCU and CPU hotplug that I > believe will clear this up. > > o TREE_PREEMPT_RCU currently uses the TREE_RCU variant of > synchronize_rcu_expedited, which is wrong. I am working on > an expedited variant for TREE_PREEMPT_RCU, but will fall > back on synchronize_rcu() for the short term if it gives me > much trouble. > > o The IPI hyperactivity from call_rcu() noted by Nick Piggin. > I believe I have identified a clean design for a fix for this. > > o Make RCU less dependent on IPIs for forcing grace periods > (but this might be best deferred to 2.6.33). > > o RCU priority boosting (2.6.33!). > > o TINY_PREEMPT_RCU (2.6.33!). > > o Squeeze another 400 bytes or so out of TINY_RCU (2.6.33!). > > > b/include/linux/rcupdate.h | 14 +++++------ > b/kernel/rcutree.c | 11 ++++----- > b/kernel/rcutree.h | 12 ++++++++++ > b/kernel/rcutree_plugin.h | 5 ---- > kernel/rcutree.c | 53 +++++++++++++++++++++++---------------------- > 5 files changed, 52 insertions(+), 43 deletions(-) For both patches: Acked-by: Josh Triplett