netdev - [PATCH] tcp_input: move out condition check from tcp_data

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Date:   Sun, 6 Aug 2017 13:51:17 +0400
From:   Ilya Matveychikov <matvejchikov@...il.com>
To:     netdev@...r.kernel.org
Subject: [PATCH] tcp_input: move out condition check from tcp_data_queue()

As tcp_data_queue() function is used just only twice it's better
to move out the first check and wrap it with inline. It saves a
single call in case the condition evaluated as true.

Signed-off-by: Ilya V. Matveychikov <matvejchikov@...il.com>
---
 net/ipv4/tcp_input.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 2920e0c..141a722 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4585,16 +4585,12 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
 
 }
 
-static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
+static void __tcp_data_queue(struct sock *sk, struct sk_buff *skb)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	bool fragstolen = false;
 	int eaten = -1;
 
-	if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) {
-		__kfree_skb(skb);
-		return;
-	}
 	skb_dst_drop(skb);
 	__skb_pull(skb, tcp_hdr(skb)->doff * 4);
 
@@ -4703,6 +4699,14 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
 	tcp_data_queue_ofo(sk, skb);
 }
 
+static inline void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
+{
+	if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq)
+		__kfree_skb(skb);
+	else
+		__tcp_data_queue(sk, skb);
+}
+
 static struct sk_buff *tcp_skb_next(struct sk_buff *skb, struct sk_buff_head *list)
 {
 	if (list)
-- 
2.7.4