From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: [PATCH net-next-2.6] net: inet_add_protocol() can use cmpxchg() Date: Thu, 9 Sep 2010 09:59:20 +0000 Message-ID: <20100909095920.GB8404@ff.dom.local> References: <20100909064222.GA6951@ff.dom.local> <1284015345.2428.37.camel@edumazet-laptop> <20100909070926.GB6951@ff.dom.local> <20100909072453.GA7383@ff.dom.local> <20100909090816.GA7450@ff.dom.local> <1284024237.2589.15.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Miller , jesse@nicira.com, netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from mail-bw0-f46.google.com ([209.85.214.46]:43496 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754333Ab0IIJ7Y (ORCPT ); Thu, 9 Sep 2010 05:59:24 -0400 Received: by bwz11 with SMTP id 11so948210bwz.19 for ; Thu, 09 Sep 2010 02:59:23 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1284024237.2589.15.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Sep 09, 2010 at 11:23:57AM +0200, Eric Dumazet wrote: > Le jeudi 09 septembre 2010 ?? 09:08 +0000, Jarek Poplawski a =E9crit = : > > xactly, without "after some time" I couldn't tell this > > either. Is seems some barriers might have been changed, but I might > > be wrong. Anyway, it would be nice to have some comment on that in > > the changelog. >=20 > Jarek, cmpxchg() is a very strong primitive, as documented > in Documentation/memory-barriers.txt : =2E.. > Its not needed to document each cmpxchg() use, because of these > strong requirements. >=20 Btw, I wonder if for readability and debuging it shouldn't be made generic as rcu_cmpxchg_pointer() etc.? Jarek P.