From: Craig Gallek <kraig@google.com>
Date: Wed, 10 Feb 2016 16:50:37 +0000 (-0500)
Subject: tcp: __tcp_hdrlen() helper
X-Git-Tag: v3.18.93~10
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=eaf3179d61514268a863cb9d50d66f6ebce1d5a0;p=thirdparty%2Fkernel%2Fstable.git

tcp: __tcp_hdrlen() helper

commit d9b3fca27385eafe61c3ca6feab6cb1e7dc77482 upstream.

tcp_hdrlen is wasteful if you already have a pointer to struct tcphdr.
This splits the size calculation into a helper function that can be
used if a struct tcphdr is already available.

Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index c2dee7deefa8c..9891c30e80317 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -29,9 +29,14 @@ static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb)
 	return (struct tcphdr *)skb_transport_header(skb);
 }
 
+static inline unsigned int __tcp_hdrlen(const struct tcphdr *th)
+{
+	return th->doff * 4;
+}
+
 static inline unsigned int tcp_hdrlen(const struct sk_buff *skb)
 {
-	return tcp_hdr(skb)->doff * 4;
+	return __tcp_hdrlen(tcp_hdr(skb));
 }
 
 static inline struct tcphdr *inner_tcp_hdr(const struct sk_buff *skb)