From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756053Ab0ECSQg (ORCPT ); Mon, 3 May 2010 14:16:36 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:53191 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755888Ab0ECSQe (ORCPT ); Mon, 3 May 2010 14:16:34 -0400 Date: Mon, 3 May 2010 11:16:29 -0700 From: "Paul E. McKenney" To: Eric Dumazet Cc: Valdis.Kletnieks@vt.edu, Andrew Morton , Peter Zijlstra , Patrick McHardy , "David S. Miller" , linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: mmotm 2010-04-28 - RCU whinges Message-ID: <20100503181629.GJ2597@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <201004290021.o3T0L04Y028017@imap1.linux-foundation.org> <5702.1272822394@localhost> <1272865137.2173.179.camel@edumazet-laptop> <5933.1272897014@localhost> <1272898726.2226.47.camel@edumazet-laptop> <5112.1272900590@localhost> <20100503154357.GF2597@linux.vnet.ibm.com> <1272903293.2226.50.camel@edumazet-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1272903293.2226.50.camel@edumazet-laptop> 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, May 03, 2010 at 06:14:53PM +0200, Eric Dumazet wrote: > Le lundi 03 mai 2010 à 08:43 -0700, Paul E. McKenney a écrit : > > > Highly recommended. ;-) > > > > And thanks to you for your testing efforts and to Eric for the fixes!!! > > > > For this last one, I think you should push following patch Paul I would be happy to if I could find the commit creating hlist_for_each_entry_continue_rcu()... I do see a ca. 2008 patch from Stephen Hemminger: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg264661.html According to http://patchwork.ozlabs.org/patch/47997/, this is going up the networking tree as of March 18, 2010. So I would be happy to push the patch below, but to do so, I will need to adopt the portion of Stephen's patch that created this primitive. Please let me know how you would like to proceed! Thanx, Paul > Followup of commit 3120438ad6 > (rcu: Disable lockdep checking in RCU list-traversal primitives) > > Or we might introduce a hlist_for_each_entry_continue_rcu_bh() macro... > > > > diff --git a/include/linux/rculist.h b/include/linux/rculist.h > index 004908b..b0c7e24 100644 > --- a/include/linux/rculist.h > +++ b/include/linux/rculist.h > @@ -435,10 +435,10 @@ static inline void hlist_add_after_rcu(struct hlist_node *prev, > * @member: the name of the hlist_node within the struct. > */ > #define hlist_for_each_entry_continue_rcu(tpos, pos, member) \ > - for (pos = rcu_dereference((pos)->next); \ > + for (pos = rcu_dereference_raw((pos)->next); \ > pos && ({ prefetch(pos->next); 1; }) && \ > ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); \ > - pos = rcu_dereference(pos->next)) > + pos = rcu_dereference_raw(pos->next)) > > > #endif /* __KERNEL__ */ > >