From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: Re: [PATCH 04/14] net: sched: implement unlocked action init API Date: Sat, 19 May 2018 18:11:04 -0300 Message-ID: <20180519211104.GB5488@localhost.localdomain> References: <1526308035-12484-1-git-send-email-vladbu@mellanox.com> <1526308035-12484-5-git-send-email-vladbu@mellanox.com> <20180514151641.GD1848@nanopsycho> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Vlad Buslov , netdev@vger.kernel.org, davem@davemloft.net, jhs@mojatatu.com, xiyou.wangcong@gmail.com, pablo@netfilter.org, kadlec@blackhole.kfki.hu, fw@strlen.de, ast@kernel.org, daniel@iogearbox.net, edumazet@google.com, keescook@chromium.org, linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, kliteyn@mellanox.com To: Jiri Pirko Return-path: Content-Disposition: inline In-Reply-To: <20180514151641.GD1848@nanopsycho> Sender: linux-kernel-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org On Mon, May 14, 2018 at 05:16:41PM +0200, Jiri Pirko wrote: > Mon, May 14, 2018 at 04:27:05PM CEST, vladbu@mellanox.com wrote: > >Add additional 'unlocked' argument to act API init functions. > >Argument is true when rtnl lock is not taken and false otherwise. > >It is required to implement actions that need to release rtnl lock before > >loading kernel module and reacquire if afterwards. > > > >Signed-off-by: Vlad Buslov > > [...] > > > >@@ -721,9 +722,11 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, > > a_o = tc_lookup_action_n(act_name); > > if (a_o == NULL) { > > #ifdef CONFIG_MODULES > >- rtnl_unlock(); > >+ if (!unlocked) > >+ rtnl_unlock(); > > request_module("act_%s", act_name); > >- rtnl_lock(); > >+ if (!unlocked) > >+ rtnl_lock(); > > Although I don't like this conditional locking scheme, I see no other > way to solve this :/ But I think would be better perhaps to rename > "unlocked" to something like "rtnl_held". Agreed. "rtnl_held" also removes the double negation, "!un...".