From 4109a2c3b91e5f38e401fc4ea56848e65e429785 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 23 Apr 2019 09:24:46 -0700 Subject: tipc: tipc_udp_recv() cleanup vs rcu verbs First thing tipc_udp_recv() does is to use rcu_dereference_sk_user_data(), and this is really hinting we already own rcu_read_lock() from the caller (UDP stack). No need to add another rcu_read_lock()/rcu_read_unlock() pair. Also use rcu_dereference() instead of rcu_dereference_rtnl() in the data path. Signed-off-by: Eric Dumazet Cc: Jon Maloy Cc: Ying Xue Signed-off-by: David S. Miller --- net/tipc/udp_media.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c index 6f166fbbfff1..7413cbc9b638 100644 --- a/net/tipc/udp_media.c +++ b/net/tipc/udp_media.c @@ -354,10 +354,9 @@ static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb) skb_pull(skb, sizeof(struct udphdr)); hdr = buf_msg(skb); - rcu_read_lock(); - b = rcu_dereference_rtnl(ub->bearer); + b = rcu_dereference(ub->bearer); if (!b) - goto rcu_out; + goto out; if (b && test_bit(0, &b->up)) { tipc_rcv(sock_net(sk), skb, b); @@ -368,11 +367,9 @@ static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb) if (unlikely(msg_user(hdr) == LINK_CONFIG)) { err = tipc_udp_rcast_disc(b, skb); if (err) - goto rcu_out; + goto out; } -rcu_out: - rcu_read_unlock(); out: kfree_skb(skb); return 0; -- cgit v1.2.3-59-g8ed1b