From 0c54b85f2828128274f319a1eb3ce7f604fe2a53 Mon Sep 17 00:00:00 2001 From: Ilpo Järvinen Date: Sat, 14 Mar 2009 14:23:05 +0000 Subject: tcp: simplify tcp_current_mss MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There's very little need for most of the callsites to get tp->xmit_goal_size updated. That will cost us divide as is, so slice the function in two. Also, the only users of the tp->xmit_goal_size are directly behind tcp_current_mss(), so there's no need to store that variable into tcp_sock at all! The drop of xmit_goal_size currently leaves 16-bit hole and some reorganization would again be necessary to change that (but I'm aiming to fill that hole with u16 xmit_goal_size_segs to cache the results of the remaining divide to get that tso on regression). Bring xmit_goal_size parts into tcp.c Signed-off-by: Ilpo Järvinen Cc: Evgeniy Polyakov Cc: Ingo Molnar Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 43 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 35 insertions(+), 8 deletions(-) (limited to 'net/ipv4/tcp.c') diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index d3f9beee74c..886596ff0aa 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -661,6 +661,37 @@ struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp) return NULL; } +static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now, + int large_allowed) +{ + struct tcp_sock *tp = tcp_sk(sk); + u32 xmit_size_goal; + + xmit_size_goal = mss_now; + + if (large_allowed && sk_can_gso(sk)) { + xmit_size_goal = ((sk->sk_gso_max_size - 1) - + inet_csk(sk)->icsk_af_ops->net_header_len - + inet_csk(sk)->icsk_ext_hdr_len - + tp->tcp_header_len); + + xmit_size_goal = tcp_bound_to_half_wnd(tp, xmit_size_goal); + xmit_size_goal -= (xmit_size_goal % mss_now); + } + + return xmit_size_goal; +} + +static int tcp_send_mss(struct sock *sk, int *size_goal, int flags) +{ + int mss_now; + + mss_now = tcp_current_mss(sk); + *size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB)); + + return mss_now; +} + static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffset, size_t psize, int flags) { @@ -677,8 +708,7 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffse clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); - mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); - size_goal = tp->xmit_size_goal; + mss_now = tcp_send_mss(sk, &size_goal, flags); copied = 0; err = -EPIPE; @@ -761,8 +791,7 @@ wait_for_memory: if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) goto do_error; - mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); - size_goal = tp->xmit_size_goal; + mss_now = tcp_send_mss(sk, &size_goal, flags); } out: @@ -844,8 +873,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, /* This should be in poll */ clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); - mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); - size_goal = tp->xmit_size_goal; + mss_now = tcp_send_mss(sk, &size_goal, flags); /* Ok commence sending. */ iovlen = msg->msg_iovlen; @@ -1007,8 +1035,7 @@ wait_for_memory: if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) goto do_error; - mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); - size_goal = tp->xmit_size_goal; + mss_now = tcp_send_mss(sk, &size_goal, flags); } } -- cgit v1.2.3-70-g09d2