From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: rib_trie / Fix inflate_threshold_root. Now=15 size=11 bits Date: Fri, 26 Jun 2009 11:21:43 -0700 Message-ID: <20090626182143.GN6771@linux.vnet.ibm.com> References: <20090626132820.GB8897@ff.dom.local> <19012.53943.734747.493480@robur.slu.se> <20090626151051.GA2714@ami.dom.local> <20090626153010.GC6771@linux.vnet.ibm.com> <20090626155410.GA6526@ami.dom.local> <20090626161500.GB6526@ami.dom.local> <20090626162340.GF6771@linux.vnet.ibm.com> <20090626164557.GB6755@ami.dom.local> <20090626170538.GK6771@linux.vnet.ibm.com> <20090626180544.GA6908@ami.dom.local> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Robert Olsson , Robert Olsson , Eric Dumazet , =?us-ascii?B?PT9JU08tODg1OS0yP1E/UGF3ZT1CM19TdGFzemV3c2tpPz0=?= , Robert Olsson , Linux Network Development list To: Jarek Poplawski Return-path: Received: from e5.ny.us.ibm.com ([32.97.182.145]:57835 "EHLO e5.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752169AbZFZSVl (ORCPT ); Fri, 26 Jun 2009 14:21:41 -0400 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e5.ny.us.ibm.com (8.13.1/8.13.1) with ESMTP id n5QIFHdv006205 for ; Fri, 26 Jun 2009 14:15:17 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v9.2) with ESMTP id n5QILiWk245780 for ; Fri, 26 Jun 2009 14:21:44 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n5QILhkq003414 for ; Fri, 26 Jun 2009 14:21:44 -0400 Content-Disposition: inline In-Reply-To: <20090626180544.GA6908@ami.dom.local> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Jun 26, 2009 at 08:05:45PM +0200, Jarek Poplawski wrote: > On Fri, Jun 26, 2009 at 10:05:38AM -0700, Paul E. McKenney wrote: > ... > > In that case, simply invoking synchronize_rcu() every once and awhile > > should take care of things. This could be at the end of every large > > trie operation, or you could even count the call_rcu() invocations and > > do a synchronize_rcu() every 100th, 1,000th, or whatever, based on > > the amount of memory available. > > OK, for now the minimal change for testing (2.6.30 needs previously > mentioned two commits from 2.6.31-rc). (I guess I'll send it with a > changelog after net-next is opened.) Looks promising to me!!! Thanx, Paul > Thanks, > Jarek P. > --- (take 4 - for testing) > > net/ipv4/fib_trie.c | 8 ++++++-- > 1 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c > index 012cf5a..98b31a1 100644 > --- a/net/ipv4/fib_trie.c > +++ b/net/ipv4/fib_trie.c > @@ -1008,7 +1008,7 @@ static void trie_rebalance(struct trie *t, struct tnode *tn) > { > int wasfull; > t_key cindex, key; > - struct tnode *tp; > + struct tnode *tp, *oldtnode = tn; > > key = tn->key; > > @@ -1028,8 +1028,12 @@ static void trie_rebalance(struct trie *t, struct tnode *tn) > } > > /* Handle last (top) tnode */ > - if (IS_TNODE(tn)) > + if (IS_TNODE(tn)) { > + /* force memory freeing after last changes */ > + if (oldtnode != tn) > + synchronize_rcu(); > tn = (struct tnode *)resize(t, (struct tnode *)tn); > + } > > rcu_assign_pointer(t->trie, (struct node *)tn); > tnode_free_flush();