From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: [PATCH net-next] bridge: remove a redundant synchronize_net() Date: Thu, 4 Apr 2013 17:35:30 +0200 Message-ID: <20130404153530.GA1688@minipsycho.brq.redhat.com> References: <1364917500.5113.176.camel@edumazet-glaptop> <20130402155822.GB29115@redhat.com> <20130402.121223.496337697838525487.davem@davemloft.net> <1364920077.5113.185.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Miller , vfalico@redhat.com, netdev@vger.kernel.org, stephen@networkplumber.org To: Eric Dumazet Return-path: Received: from mail-wi0-f180.google.com ([209.85.212.180]:61186 "EHLO mail-wi0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759770Ab3DDPff (ORCPT ); Thu, 4 Apr 2013 11:35:35 -0400 Received: by mail-wi0-f180.google.com with SMTP id c10so2739654wiw.13 for ; Thu, 04 Apr 2013 08:35:34 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1364920077.5113.185.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: Tue, Apr 02, 2013 at 06:27:57PM CEST, eric.dumazet@gmail.com wrote: >On Tue, 2013-04-02 at 12:12 -0400, David Miller wrote: > >> Note that we have a few spots now that do two synchronize_net()'s per >> opertaion, such as team port removal, and openvswitch has such a path >> as well. They all are of the form: >> >> netdev_rx_handler_unregister() >> ... >> lots of other stuff >> ... >> synchronize_net(); >> >> So might be harder to factor back out than this br_if.c case. >> > >Strange, I do see call_rcu() in openvswitch, not a synchronize_{net| >rcu}(). Probably OK to leave as is, as it's not a big deal. > >I'll let Jiri handle the team driver change, as its not clear what >synchronize_rcu() call in team_port_del() is protecting It can be converted now to call_rcu. synchronize_rcu is making sure no packet is in flight when changing modes. > > >