Re: [PATCH v2 net-next 2/2] RDS-TCP: Support multiple RDS-TCP listen endpoints, one per netns.

On Mon, Aug 3, 2015 at 10:29 PM, Sowmini Varadhan
[off-list ref] wrote:

+static struct pernet_operations rds_tcp_net_ops = {
+       .init = rds_tcp_init_net,
+       .exit = rds_tcp_exit_net,
+       .id = &rds_tcp_netid,
+       .size = sizeof(struct rds_tcp_net),
+};
+
+static void rds_tcp_kill_sock(struct net *net)
+{
+       struct rds_tcp_connection *tc, *_tc;
+       struct sock *sk;
+       struct list_head tmp_list;
+       struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
+
+       rds_tcp_listen_stop(rtn->rds_tcp_listen_sock);
+       rtn->rds_tcp_listen_sock = NULL;
+       flush_work(&rtn->rds_tcp_accept_w);
+       INIT_LIST_HEAD(&tmp_list);

Can be folded as LIST_HEAD(tmp_list).

+       spin_lock_irq(&rds_tcp_conn_lock);
+       list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
+               struct net *c_net = read_pnet(&tc->conn->c_net);
+
+               if (net != c_net || !tc->t_sock)
+                       continue;
+               list_del(&tc->t_tcp_node);
+               list_add_tail(&tc->t_tcp_node, &tmp_list);

list_move_tail().

+       }
+       spin_unlock_irq(&rds_tcp_conn_lock);
+       list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) {
+               sk = tc->t_sock->sk;
+               sk->sk_prot->disconnect(sk, 0);
+               tcp_done(sk);
+               if (tc->conn->c_passive)
+                       rds_conn_destroy(tc->conn->c_passive);
+               rds_conn_destroy(tc->conn);
+       }
+}
+
+static int rds_tcp_dev_event(struct notifier_block *this,
+                            unsigned long event, void *ptr)
+{
+       struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+       /* rds-tcp registers as a pernet subys, so the ->exit will only
+        * get invoked after network acitivity has quiesced. We need to
+        * clean up all sockets  to quiesce network activity, and use
+        * the unregistration of the per-net loopback device as a trigger
+        * to start that cleanup.
+        */
+       if (event == NETDEV_UNREGISTER_FINAL &&
+           strcmp(dev->name, "lo") == 0)

Shouldn't check device name, check ->ifindex == LOOPBACK_IFINDEX
instead.

+               rds_tcp_kill_sock(dev_net(dev));
+
+       return NOTIFY_DONE;
+}
+

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