diff options
-rw-r--r-- | include/net/tcp.h | 5 | ||||
-rw-r--r-- | net/ipv4/tcp_input.c | 13 | ||||
-rw-r--r-- | net/ipv4/tcp_output.c | 33 |
3 files changed, 22 insertions, 29 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index 0d637e9..6fa8083 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -61,9 +61,6 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo); */ #define MAX_TCP_WINDOW 32767U -/* Offer an initial receive window of 10 mss. */ -#define TCP_DEFAULT_INIT_RCVWND 10 - /* Minimal accepted MSS. It is (60+60+8) - (20+20). */ #define TCP_MIN_MSS 88U @@ -1047,6 +1044,8 @@ static inline void tcp_sack_reset(struct tcp_options_received *rx_opt) rx_opt->num_sacks = 0; } +extern u32 tcp_default_init_rwnd(u32 mss); + /* Determine a window scaling and initial window to offer. */ extern void tcp_select_initial_window(int __space, __u32 mss, __u32 *rcv_wnd, __u32 *window_clamp, diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 907311c..46271cdc 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -347,22 +347,13 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb) } /* 3. Tuning rcvbuf, when connection enters established state. */ - static void tcp_fixup_rcvbuf(struct sock *sk) { u32 mss = tcp_sk(sk)->advmss; - u32 icwnd = TCP_DEFAULT_INIT_RCVWND; int rcvmem; - /* Limit to 10 segments if mss <= 1460, - * or 14600/mss segments, with a minimum of two segments. - */ - if (mss > 1460) - icwnd = max_t(u32, (1460 * TCP_DEFAULT_INIT_RCVWND) / mss, 2); - - rcvmem = 2 * SKB_TRUESIZE(mss + MAX_TCP_HEADER); - - rcvmem *= icwnd; + rcvmem = 2 * SKB_TRUESIZE(mss + MAX_TCP_HEADER) * + tcp_default_init_rwnd(mss); if (sk->sk_rcvbuf < rcvmem) sk->sk_rcvbuf = min(rcvmem, sysctl_tcp_rmem[2]); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index ec335fa..3dd46ea 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -181,6 +181,21 @@ static inline void tcp_event_ack_sent(struct sock *sk, unsigned int pkts) inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); } + +u32 tcp_default_init_rwnd(u32 mss) +{ + /* Initial receive window should be twice of TCP_INIT_CWND to + * enable proper sending of new unset data during fast recovery + * (RFC 3517, Section 4, NextSeg() rule (2)). Further place a + * limit when mss is larger than 1460. + */ + u32 init_rwnd = TCP_INIT_CWND * 2; + + if (mss > 1460) + init_rwnd = max((1460 * init_rwnd) / mss, 2U); + return init_rwnd; +} + /* Determine a window scaling and initial window to offer. * Based on the assumption that the given amount of space * will be offered. Store the results in the tp structure. @@ -230,22 +245,10 @@ void tcp_select_initial_window(int __space, __u32 mss, } } - /* Set initial window to a value enough for senders starting with - * initial congestion window of TCP_DEFAULT_INIT_RCVWND. Place - * a limit on the initial window when mss is larger than 1460. - */ if (mss > (1 << *rcv_wscale)) { - int init_cwnd = TCP_DEFAULT_INIT_RCVWND; - if (mss > 1460) - init_cwnd = - max_t(u32, (1460 * TCP_DEFAULT_INIT_RCVWND) / mss, 2); - /* when initializing use the value from init_rcv_wnd - * rather than the default from above - */ - if (init_rcv_wnd) - *rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss); - else - *rcv_wnd = min(*rcv_wnd, init_cwnd * mss); + if (!init_rcv_wnd) /* Use default unless specified otherwise */ + init_rcv_wnd = tcp_default_init_rwnd(mss); + *rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss); } /* Set the clamp no higher than max representable value */ |