Commit 98f6c533 authored Feb 13, 2018 by Kirill Tkhai Committed by David S. Miller Feb 13, 2018

net: Assign net to net_namespace_list in setup_net()



This patch merges two repeating pieces of code in one,
and they will live in setup_net() now.

The only change is that assignment:

	init_net_initialized = true;

becomes reordered with:

	list_add_tail_rcu(&net->list, &net_namespace_list);

The order does not have visible effect, and it is a simple
cleanup because of:

init_net_initialized is used in !CONFIG_NET_NS case
to order proc_net_ns_ops registration occuring at boot time:

	start_kernel()->proc_root_init()->proc_net_init(),
with
	net_ns_init()->setup_net(&init_net, &init_user_ns)

also occuring in boot time from the same init_task.

When there are no another tasks to race with them,
for the single task it does not matter, which order
two sequential independent loads should be made.
So we make them reordered.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent cf19e5e2

net/core/net_namespace.c

+3 −10

Original line number	Diff line number	Diff line
		@@ -303,6 +303,9 @@ static __net_init int setup_net(struct net net, struct user_namespace user_ns)
		if (error < 0)
		goto out_undo;
		}
		rtnl_lock();
		list_add_tail_rcu(&net->list, &net_namespace_list);
		rtnl_unlock();
		out:
		return error;

		@@ -424,11 +427,6 @@ struct net *copy_net_ns(unsigned long flags,

		net->ucounts = ucounts;
		rv = setup_net(net, user_ns);
		if (rv == 0) {
		rtnl_lock();
		list_add_tail_rcu(&net->list, &net_namespace_list);
		rtnl_unlock();
		}
		mutex_unlock(&net_mutex);
		if (rv < 0) {
		dec_net_namespaces(ucounts);
		@@ -880,11 +878,6 @@ static int __init net_ns_init(void)
		panic("Could not setup the initial network namespace");

		init_net_initialized = true;

		rtnl_lock();
		list_add_tail_rcu(&init_net.list, &net_namespace_list);
		rtnl_unlock();

		mutex_unlock(&net_mutex);

		register_pernet_subsys(&net_ns_ops);

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