There is no need to process outstanding netlink user->kernel packets
during rtnl_unlock now. There is no rtnl_trylock in the rtnetlink_rcv
anymore.
Normal code path is the following:
netlink_sendmsg
netlink_unicast
netlink_sendskb
skb_queue_tail
netlink_data_ready
rtnetlink_rcv
mutex_lock(&rtnl_mutex);
netlink_run_queue(sk, qlen, &rtnetlink_rcv_msg);
mutex_unlock(&rtnl_mutex);
So, it is possible, that packets can be present in the rtnl->sk_receive_queue
during rtnl_unlock, but there is no need to process them at that moment as
rtnetlink_rcv for that packet is pending.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
--- ./net/core/rtnetlink.c.rtnl2 2007-08-26 19:30:38.000000000 +0400
+++ ./net/core/rtnetlink.c 2007-10-01 13:09:03.000000000 +0400
@@ -75,8 +75,6 @@ void __rtnl_unlock(void)
void rtnl_unlock(void)
{
mutex_unlock(&rtnl_mutex);
- if (rtnl && rtnl->sk_receive_queue.qlen)
- rtnl->sk_data_ready(rtnl, 0);
netdev_run_todo();
}
@@ -1319,11 +1317,9 @@ static void rtnetlink_rcv(struct sock *s
unsigned int qlen = 0;
do {
- mutex_lock(&rtnl_mutex);
+ rtnl_lock();
qlen = netlink_run_queue(sk, qlen, &rtnetlink_rcv_msg);
- mutex_unlock(&rtnl_mutex);
-
- netdev_run_todo();
+ rtnl_unlock();
} while (qlen);
}