From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Horman Subject: Re: [PATCH v1 net-next 1/5] drop_monitor: import netnamespace framework Date: Wed, 12 Jul 2017 09:37:48 -0400 Message-ID: <20170712133748.GA21036@hmswarspite.think-freely.org> References: <1499856053-30475-1-git-send-email-zhangjunweimartin@didichuxing.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: davem@davemloft.net, netdev@vger.kernel.org, zhangjunweimartin@didichuxing.com To: martinbj2008@gmail.com Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:53734 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750991AbdGLNiI (ORCPT ); Wed, 12 Jul 2017 09:38:08 -0400 Content-Disposition: inline In-Reply-To: <1499856053-30475-1-git-send-email-zhangjunweimartin@didichuxing.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Jul 12, 2017 at 06:40:49PM +0800, martinbj2008@gmail.com wrote: > From: martin Zhang > > This is a serial patch for drop monitor, in order to support net namespace. > > Import two struct to support net ns: > > 1. struct per_ns_dm_cb: > Just like its name, it is used in per net ns. > > In this patch it is empty, but in following patch, these field will be added. > a. trace_state: every net ns has a switch to indicate the trace state. > b. ns_dm_mutex: the mutex will only work and keep exclusive operatons in a net ns. > c. hw_stats_list: monitor for NAPI of net device. > > 2. ns_pcpu_dm_data > It is used to replace per_cpu_dm_data under per net ns. > > per_cpu_dm_data will only keep the dm_alert_work, and the other field > will be moved to ns_pcpu_dm_data. They do same thing just like current > code, and the only difference is under per net ns. > > Keep there is a work under percpu, to send alter netlink message. > > Signed-off-by: martin Zhang > --- > The dropwatch is a very useful tool to diagnose network problem, > which give us greate help. > Dropwatch could not work under container(net namespace). > It is a pitty, so let it support net ns. > Sorry, Im having a hard time wrapping my head around this. Why exactly is it that dropwatch won't work in a namespaced environment? IIRC, the kfree tracepoints are namespace agnostic, and so running dropwatch anywhere should result in seeing drops in all namespaces. I grant that perhaps it would be nice to filter on a namespace, but it should all 'just work' for some definition of the term, no? Neil > net/core/drop_monitor.c | 41 +++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 41 insertions(+) > > diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c > index 70ccda2..6a75e04 100644 > --- a/net/core/drop_monitor.c > +++ b/net/core/drop_monitor.c > @@ -32,6 +32,10 @@ > #include > > #include > +#include > +#include > +#include > +#include > > #define TRACE_ON 1 > #define TRACE_OFF 0 > @@ -41,6 +45,13 @@ > * and the work handle that will send up > * netlink alerts > */ > + > +struct ns_pcpu_dm_data { > +}; > + > +struct per_ns_dm_cb { > +}; > + > static int trace_state = TRACE_OFF; > static DEFINE_MUTEX(trace_state_mutex); > > @@ -59,6 +70,7 @@ struct dm_hw_stat_delta { > unsigned long last_drop_val; > }; > > +static int dm_net_id __read_mostly; > static struct genl_family net_drop_monitor_family; > > static DEFINE_PER_CPU(struct per_cpu_dm_data, dm_cpu_data); > @@ -382,6 +394,33 @@ static int dropmon_net_event(struct notifier_block *ev_block, > .notifier_call = dropmon_net_event > }; > > +static int __net_init dm_net_init(struct net *net) > +{ > + struct per_ns_dm_cb *ns_dm_cb; > + > + ns_dm_cb = net_generic(net, dm_net_id); > + if (!ns_dm_cb) > + return -ENOMEM; > + > + return 0; > +} > + > +static void __net_exit dm_net_exit(struct net *net) > +{ > + struct per_ns_dm_cb *ns_dm_cb; > + > + ns_dm_cb = net_generic(net, dm_net_id); > + if (!ns_dm_cb) > + return; > +} > + > +static struct pernet_operations dm_net_ops = { > + .init = dm_net_init, > + .exit = dm_net_exit, > + .id = &dm_net_id, > + .size = sizeof(struct per_ns_dm_cb), > +}; > + > static int __init init_net_drop_monitor(void) > { > struct per_cpu_dm_data *data; > @@ -393,6 +432,7 @@ static int __init init_net_drop_monitor(void) > pr_err("Unable to store program counters on this arch, Drop monitor failed\n"); > return -ENOSPC; > } > + rc = register_pernet_subsys(&dm_net_ops); > > rc = genl_register_family(&net_drop_monitor_family); > if (rc) { > @@ -441,6 +481,7 @@ static void exit_net_drop_monitor(void) > * or pending schedule calls > */ > > + unregister_pernet_subsys(&dm_net_ops); > for_each_possible_cpu(cpu) { > data = &per_cpu(dm_cpu_data, cpu); > del_timer_sync(&data->send_timer); > -- > 1.8.3.1 > >