From 3d97d88e8091f3501e016f6b4ce45a32c4b8f2f6 Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Tue, 29 May 2018 23:27:31 +0800 Subject: [PATCH] tcp: minor optimization around tcp_hdr() usage in receive path This is additional to the commit ea1627c20c34 ("tcp: minor optimizations around tcp_hdr() usage"). At this point, skb->data is same with tcp_hdr() as tcp header has not been pulled yet. So use the less expensive one to get the tcp header. Remove the third parameter of tcp_rcv_established() and put it into the function body. Furthermore, the local variables are listed as a reverse christmas tree :) Cc: Eric Dumazet Signed-off-by: Yafang Shao Signed-off-by: David S. Miller --- include/net/tcp.h | 3 +-- include/trace/events/tcp.h | 5 +++-- net/ipv4/tcp_input.c | 6 +++--- net/ipv4/tcp_ipv4.c | 2 +- net/ipv6/tcp_ipv6.c | 2 +- 5 files changed, 9 insertions(+), 9 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 952d842a604a..029a51b91742 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -334,8 +334,7 @@ void tcp_write_timer_handler(struct sock *sk); void tcp_delack_timer_handler(struct sock *sk); int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg); int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb); -void tcp_rcv_established(struct sock *sk, struct sk_buff *skb, - const struct tcphdr *th); +void tcp_rcv_established(struct sock *sk, struct sk_buff *skb); void tcp_rcv_space_adjust(struct sock *sk); int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp); void tcp_twsk_destructor(struct sock *sk); diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h index 703abb6e11fa..ac55b328d61b 100644 --- a/include/trace/events/tcp.h +++ b/include/trace/events/tcp.h @@ -248,8 +248,9 @@ TRACE_EVENT(tcp_probe, ), TP_fast_assign( - const struct tcp_sock *tp = tcp_sk(sk); + const struct tcphdr *th = (const struct tcphdr *)skb->data; const struct inet_sock *inet = inet_sk(sk); + const struct tcp_sock *tp = tcp_sk(sk); memset(__entry->saddr, 0, sizeof(struct sockaddr_in6)); memset(__entry->daddr, 0, sizeof(struct sockaddr_in6)); @@ -261,7 +262,7 @@ TRACE_EVENT(tcp_probe, __entry->dport = ntohs(inet->inet_dport); __entry->mark = skb->mark; - __entry->data_len = skb->len - tcp_hdrlen(skb); + __entry->data_len = skb->len - __tcp_hdrlen(th); __entry->snd_nxt = tp->snd_nxt; __entry->snd_una = tp->snd_una; __entry->snd_cwnd = tp->snd_cwnd; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 1191cac72109..d5ffb573ca4d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5390,11 +5390,11 @@ discard: * the rest is checked inline. Fast processing is turned on in * tcp_data_queue when everything is OK. */ -void tcp_rcv_established(struct sock *sk, struct sk_buff *skb, - const struct tcphdr *th) +void tcp_rcv_established(struct sock *sk, struct sk_buff *skb) { - unsigned int len = skb->len; + const struct tcphdr *th = (const struct tcphdr *)skb->data; struct tcp_sock *tp = tcp_sk(sk); + unsigned int len = skb->len; /* TCP congestion window tracking */ trace_tcp_probe(sk, skb); diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index adbdb503db0c..749b0ef9f405 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1486,7 +1486,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) sk->sk_rx_dst = NULL; } } - tcp_rcv_established(sk, skb, tcp_hdr(skb)); + tcp_rcv_established(sk, skb); return 0; } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 7d47c2b550a9..8764a63abd91 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1322,7 +1322,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) } } - tcp_rcv_established(sk, skb, tcp_hdr(skb)); + tcp_rcv_established(sk, skb); if (opt_skb) goto ipv6_pktoptions; return 0;