From: Eric Dumazet <[email protected]> Date: Fri, 13 May 2016 09:16:40 -0700
> From: Eric Dumazet <[email protected]> > > tcp_hdr() is slightly more expensive than using skb->data in contexts > where we know they point to the same byte. > > In receive path, tcp_v4_rcv() and tcp_v6_rcv() are in this situation, > as tcp header has not been pulled yet. > > In output path, the same can be said when we just pushed the tcp header > in the skb, in tcp_transmit_skb() and tcp_make_synack() > > Also factorize the two checks for tcb->tcp_flags & TCPHDR_SYN in > tcp_transmit_skb() and pass tcp header pointer to tcp_ecn_send(), > so that compiler can further optimize and avoid a reload. > > Signed-off-by: Eric Dumazet <[email protected]> Applied.
