From f69ad292cfd13aa7ee00847320c6bb9ba2154e87 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 11 Jun 2015 09:15:18 -0700 Subject: tcp: fill shinfo->gso_size at last moment In commit cd7d8498c9a5 ("tcp: change tcp_skb_pcount() location") we stored gso_segs in a temporary cache hot location. This patch does the same for gso_size. This allows to save 2 cache line misses in tcp xmit path for the last packet that is considered but not sent because of various conditions (cwnd, tso defer, receiver window, TSQ...) Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'net/ipv4/tcp_input.c') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 70a6fa8ecbd3..684f095d196e 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1316,12 +1316,12 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, * code can come after this skb later on it's better to keep * setting gso_size to something. */ - if (!skb_shinfo(prev)->gso_size) - skb_shinfo(prev)->gso_size = mss; + if (!TCP_SKB_CB(prev)->tcp_gso_size) + TCP_SKB_CB(prev)->tcp_gso_size = mss; /* CHECKME: To clear or not to clear? Mimics normal skb currently */ if (tcp_skb_pcount(skb) <= 1) - skb_shinfo(skb)->gso_size = 0; + TCP_SKB_CB(skb)->tcp_gso_size = 0; /* Difference in this won't matter, both ACKed by the same cumul. ACK */ TCP_SKB_CB(prev)->sacked |= (TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS); @@ -2248,7 +2248,7 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head) (oldcnt >= packets)) break; - mss = skb_shinfo(skb)->gso_size; + mss = tcp_skb_mss(skb); err = tcp_fragment(sk, skb, (packets - oldcnt) * mss, mss, GFP_ATOMIC); if (err < 0) -- cgit v1.2.3-59-g8ed1b