tcp: out_of_order_queue do not use its lock

TCP out_of_order_queue lock is not used, as queue manipulation happens with socket lock held and we therefore use the lockless skb queue routines (as __skb_queue_head()) We can use __skb_queue_head_init() instead of skb_queue_head_init() to make this more consistent. Signed-off-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]>
tomthink · Jan 6, 2014 · 996b175 · 996b175
1 parent 0b23810
commit 996b175
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Showing 3 changed files with 6 additions and 3 deletions.
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
@@ -248,7 +248,10 @@ struct tcp_sock {
 	struct sk_buff* lost_skb_hint;
 	struct sk_buff *retransmit_skb_hint;
 
-	struct sk_buff_head	out_of_order_queue; /* Out of order segments go here */
+	/* OOO segments go in this list. Note that socket lock must be held,
+	 * as we do not use sk_buff_head lock.
+	 */
+	struct sk_buff_head	out_of_order_queue;
 
 	/* SACKs data, these 2 need to be together (see tcp_options_write) */
 	struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
@@ -381,7 +381,7 @@ void tcp_init_sock(struct sock *sk)
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	skb_queue_head_init(&tp->out_of_order_queue);
+	__skb_queue_head_init(&tp->out_of_order_queue);
 	tcp_init_xmit_timers(sk);
 	tcp_prequeue_init(tp);
 	INIT_LIST_HEAD(&tp->tsq_node);

diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
@@ -425,7 +425,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
 
 		tcp_set_ca_state(newsk, TCP_CA_Open);
 		tcp_init_xmit_timers(newsk);
-		skb_queue_head_init(&newtp->out_of_order_queue);
+		__skb_queue_head_init(&newtp->out_of_order_queue);
 		newtp->write_seq = newtp->pushed_seq = treq->snt_isn + 1;
 
 		newtp->rx_opt.saw_tstamp = 0;