/* Adapt the MSS value used to make delayed ack decision to the
* real world.
*/
-static inline void tcp_measure_rcv_mss(struct sock *sk,
- const struct sk_buff *skb)
+static void tcp_measure_rcv_mss(struct sock *sk,
+ const struct sk_buff *skb)
{
struct inet_connection_sock *icsk = inet_csk(sk);
const unsigned int lss = icsk->icsk_ack.last_seg_size;
return 0;
}
-static inline void tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
- struct sk_buff *skb)
+static void tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
+ struct sk_buff *skb)
{
/* Check #1 */
if (tp->rcv_ssthresh < tp->window_clamp &&
tp->rcv_ssthresh = min(tp->window_clamp, 2U*tp->advmss);
}
+
+/* Initialize RCV_MSS value.
+ * RCV_MSS is an our guess about MSS used by the peer.
+ * We haven't any direct information about the MSS.
+ * It's better to underestimate the RCV_MSS rather than overestimate.
+ * Overestimations make us ACKing less frequently than needed.
+ * Underestimations are more easy to detect and fix by tcp_measure_rcv_mss().
+ */
+void tcp_initialize_rcv_mss(struct sock *sk)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ unsigned int hint = min_t(unsigned int, tp->advmss, tp->mss_cache);
+
+ hint = min(hint, tp->rcv_wnd/2);
+ hint = min(hint, TCP_MIN_RCVMSS);
+ hint = max(hint, TCP_MIN_MSS);
+
+ inet_csk(sk)->icsk_ack.rcv_mss = hint;
+}
+
/* Receiver "autotuning" code.
*
* The algorithm for RTT estimation w/o timestamps is based on
* are stalled on filesystem I/O.
*
* Also, since we are only going for a minimum in the
- * non-timestamp case, we do not smoother things out
+ * non-timestamp case, we do not smooth things out
* else with timestamps disabled convergence takes too
* long.
*/
*
* Funny. This algorithm seems to be very broken.
* These formulae increase RTO, when it should be decreased, increase
- * too slowly, when it should be increased fastly, decrease too fastly
+ * too slowly, when it should be increased quickly, decrease too quickly
* etc. I guess in BSD RTO takes ONE value, so that it is absolutely
* does not matter how to _calculate_ it. Seems, it was trap
* that VJ failed to avoid. 8)
return min_t(__u32, cwnd, tp->snd_cwnd_clamp);
}
+/* Set slow start threshold and cwnd not falling to slow start */
+void tcp_enter_cwr(struct sock *sk)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ tp->prior_ssthresh = 0;
+ tp->bytes_acked = 0;
+ if (inet_csk(sk)->icsk_ca_state < TCP_CA_CWR) {
+ tp->undo_marker = 0;
+ tp->snd_ssthresh = inet_csk(sk)->icsk_ca_ops->ssthresh(sk);
+ tp->snd_cwnd = min(tp->snd_cwnd,
+ tcp_packets_in_flight(tp) + 1U);
+ tp->snd_cwnd_cnt = 0;
+ tp->high_seq = tp->snd_nxt;
+ tp->snd_cwnd_stamp = tcp_time_stamp;
+ TCP_ECN_queue_cwr(tp);
+
+ tcp_set_ca_state(sk, TCP_CA_CWR);
+ }
+}
+
/* Initialize metrics on socket. */
static void tcp_init_metrics(struct sock *sk)
int prior_fackets;
u32 lost_retrans = 0;
int flag = 0;
+ int dup_sack = 0;
int i;
if (!tp->sacked_out)
tp->fackets_out = 0;
prior_fackets = tp->fackets_out;
- for (i=0; i<num_sacks; i++, sp++) {
- struct sk_buff *skb;
- __u32 start_seq = ntohl(sp->start_seq);
- __u32 end_seq = ntohl(sp->end_seq);
- int fack_count = 0;
- int dup_sack = 0;
+ /* SACK fastpath:
+ * if the only SACK change is the increase of the end_seq of
+ * the first block then only apply that SACK block
+ * and use retrans queue hinting otherwise slowpath */
+ flag = 1;
+ for (i = 0; i< num_sacks; i++) {
+ __u32 start_seq = ntohl(sp[i].start_seq);
+ __u32 end_seq = ntohl(sp[i].end_seq);
+
+ if (i == 0){
+ if (tp->recv_sack_cache[i].start_seq != start_seq)
+ flag = 0;
+ } else {
+ if ((tp->recv_sack_cache[i].start_seq != start_seq) ||
+ (tp->recv_sack_cache[i].end_seq != end_seq))
+ flag = 0;
+ }
+ tp->recv_sack_cache[i].start_seq = start_seq;
+ tp->recv_sack_cache[i].end_seq = end_seq;
/* Check for D-SACK. */
if (i == 0) {
if (before(ack, prior_snd_una - tp->max_window))
return 0;
}
+ }
+
+ if (flag)
+ num_sacks = 1;
+ else {
+ int j;
+ tp->fastpath_skb_hint = NULL;
+
+ /* order SACK blocks to allow in order walk of the retrans queue */
+ for (i = num_sacks-1; i > 0; i--) {
+ for (j = 0; j < i; j++){
+ if (after(ntohl(sp[j].start_seq),
+ ntohl(sp[j+1].start_seq))){
+ sp[j].start_seq = htonl(tp->recv_sack_cache[j+1].start_seq);
+ sp[j].end_seq = htonl(tp->recv_sack_cache[j+1].end_seq);
+ sp[j+1].start_seq = htonl(tp->recv_sack_cache[j].start_seq);
+ sp[j+1].end_seq = htonl(tp->recv_sack_cache[j].end_seq);
+ }
+
+ }
+ }
+ }
+
+ /* clear flag as used for different purpose in following code */
+ flag = 0;
+
+ for (i=0; i<num_sacks; i++, sp++) {
+ struct sk_buff *skb;
+ __u32 start_seq = ntohl(sp->start_seq);
+ __u32 end_seq = ntohl(sp->end_seq);
+ int fack_count;
+
+ /* Use SACK fastpath hint if valid */
+ if (tp->fastpath_skb_hint) {
+ skb = tp->fastpath_skb_hint;
+ fack_count = tp->fastpath_cnt_hint;
+ } else {
+ skb = sk->sk_write_queue.next;
+ fack_count = 0;
+ }
/* Event "B" in the comment above. */
if (after(end_seq, tp->high_seq))
flag |= FLAG_DATA_LOST;
- sk_stream_for_retrans_queue(skb, sk) {
+ sk_stream_for_retrans_queue_from(skb, sk) {
int in_sack, pcount;
u8 sacked;
+ tp->fastpath_skb_hint = skb;
+ tp->fastpath_cnt_hint = fack_count;
+
/* The retransmission queue is always in order, so
* we can short-circuit the walk early.
*/
TCP_SKB_CB(skb)->sacked &= ~(TCPCB_LOST|TCPCB_SACKED_RETRANS);
tp->lost_out -= tcp_skb_pcount(skb);
tp->retrans_out -= tcp_skb_pcount(skb);
+
+ /* clear lost hint */
+ tp->retransmit_skb_hint = NULL;
}
} else {
/* New sack for not retransmitted frame,
if (sacked & TCPCB_LOST) {
TCP_SKB_CB(skb)->sacked &= ~TCPCB_LOST;
tp->lost_out -= tcp_skb_pcount(skb);
+
+ /* clear lost hint */
+ tp->retransmit_skb_hint = NULL;
}
}
(TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS)) {
TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
tp->retrans_out -= tcp_skb_pcount(skb);
+ tp->retransmit_skb_hint = NULL;
}
}
}
TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
tp->retrans_out -= tcp_skb_pcount(skb);
+ /* clear lost hint */
+ tp->retransmit_skb_hint = NULL;
+
if (!(TCP_SKB_CB(skb)->sacked&(TCPCB_LOST|TCPCB_SACKED_ACKED))) {
tp->lost_out += tcp_skb_pcount(skb);
TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
tcp_set_ca_state(sk, TCP_CA_Loss);
tp->high_seq = tp->frto_highmark;
TCP_ECN_queue_cwr(tp);
+
+ clear_all_retrans_hints(tp);
}
void tcp_clear_retrans(struct tcp_sock *tp)
tcp_set_ca_state(sk, TCP_CA_Loss);
tp->high_seq = tp->snd_nxt;
TCP_ECN_queue_cwr(tp);
+
+ clear_all_retrans_hints(tp);
}
static int tcp_check_sack_reneging(struct sock *sk)
int packets, u32 high_seq)
{
struct sk_buff *skb;
- int cnt = packets;
+ int cnt;
- BUG_TRAP(cnt <= tp->packets_out);
+ BUG_TRAP(packets <= tp->packets_out);
+ if (tp->lost_skb_hint) {
+ skb = tp->lost_skb_hint;
+ cnt = tp->lost_cnt_hint;
+ } else {
+ skb = sk->sk_write_queue.next;
+ cnt = 0;
+ }
- sk_stream_for_retrans_queue(skb, sk) {
- cnt -= tcp_skb_pcount(skb);
- if (cnt < 0 || after(TCP_SKB_CB(skb)->end_seq, high_seq))
+ sk_stream_for_retrans_queue_from(skb, sk) {
+ /* TODO: do this better */
+ /* this is not the most efficient way to do this... */
+ tp->lost_skb_hint = skb;
+ tp->lost_cnt_hint = cnt;
+ cnt += tcp_skb_pcount(skb);
+ if (cnt > packets || after(TCP_SKB_CB(skb)->end_seq, high_seq))
break;
if (!(TCP_SKB_CB(skb)->sacked&TCPCB_TAGBITS)) {
TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
tp->lost_out += tcp_skb_pcount(skb);
+
+ /* clear xmit_retransmit_queue hints
+ * if this is beyond hint */
+ if(tp->retransmit_skb_hint != NULL &&
+ before(TCP_SKB_CB(skb)->seq,
+ TCP_SKB_CB(tp->retransmit_skb_hint)->seq)) {
+
+ tp->retransmit_skb_hint = NULL;
+ }
}
}
tcp_sync_left_out(tp);
if (tcp_head_timedout(sk, tp)) {
struct sk_buff *skb;
- sk_stream_for_retrans_queue(skb, sk) {
- if (tcp_skb_timedout(sk, skb) &&
- !(TCP_SKB_CB(skb)->sacked&TCPCB_TAGBITS)) {
+ skb = tp->scoreboard_skb_hint ? tp->scoreboard_skb_hint
+ : sk->sk_write_queue.next;
+
+ sk_stream_for_retrans_queue_from(skb, sk) {
+ if (!tcp_skb_timedout(sk, skb))
+ break;
+
+ if (!(TCP_SKB_CB(skb)->sacked&TCPCB_TAGBITS)) {
TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
tp->lost_out += tcp_skb_pcount(skb);
+
+ /* clear xmit_retrans hint */
+ if (tp->retransmit_skb_hint &&
+ before(TCP_SKB_CB(skb)->seq,
+ TCP_SKB_CB(tp->retransmit_skb_hint)->seq))
+
+ tp->retransmit_skb_hint = NULL;
}
}
+
+ tp->scoreboard_skb_hint = skb;
+
tcp_sync_left_out(tp);
}
}
}
tcp_moderate_cwnd(tp);
tp->snd_cwnd_stamp = tcp_time_stamp;
+
+ /* There is something screwy going on with the retrans hints after
+ an undo */
+ clear_all_retrans_hints(tp);
}
static inline int tcp_may_undo(struct tcp_sock *tp)
sk_stream_for_retrans_queue(skb, sk) {
TCP_SKB_CB(skb)->sacked &= ~TCPCB_LOST;
}
+
+ clear_all_retrans_hints(tp);
+
DBGUNDO(sk, tp, "partial loss");
tp->lost_out = 0;
tp->left_out = tp->sacked_out;
tcp_ack_no_tstamp(sk, seq_rtt, flag);
}
-static inline void tcp_cong_avoid(struct sock *sk, u32 ack, u32 rtt,
- u32 in_flight, int good)
+static void tcp_cong_avoid(struct sock *sk, u32 ack, u32 rtt,
+ u32 in_flight, int good)
{
const struct inet_connection_sock *icsk = inet_csk(sk);
icsk->icsk_ca_ops->cong_avoid(sk, ack, rtt, in_flight, good);
* RFC2988 recommends to restart timer to now+rto.
*/
-static inline void tcp_ack_packets_out(struct sock *sk, struct tcp_sock *tp)
+static void tcp_ack_packets_out(struct sock *sk, struct tcp_sock *tp)
{
if (!tp->packets_out) {
inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
return acked;
}
-static inline u32 tcp_usrtt(const struct sk_buff *skb)
+static u32 tcp_usrtt(const struct sk_buff *skb)
{
struct timeval tv, now;
tcp_packets_out_dec(tp, skb);
__skb_unlink(skb, &sk->sk_write_queue);
sk_stream_free_skb(sk, skb);
+ clear_all_retrans_hints(tp);
}
if (acked&FLAG_ACKED) {
if (nwin > tp->max_window) {
tp->max_window = nwin;
- tcp_sync_mss(sk, tp->pmtu_cookie);
+ tcp_sync_mss(sk, inet_csk(sk)->icsk_pmtu_cookie);
}
}
}
/* Fast parse options. This hopes to only see timestamps.
* If it is wrong it falls back on tcp_parse_options().
*/
-static inline int tcp_fast_parse_options(struct sk_buff *skb, struct tcphdr *th,
- struct tcp_sock *tp)
+static int tcp_fast_parse_options(struct sk_buff *skb, struct tcphdr *th,
+ struct tcp_sock *tp)
{
if (th->doff == sizeof(struct tcphdr)>>2) {
tp->rx_opt.saw_tstamp = 0;
}
}
-static __inline__ int
-tcp_sack_extend(struct tcp_sack_block *sp, u32 seq, u32 end_seq)
+static inline int tcp_sack_extend(struct tcp_sack_block *sp, u32 seq, u32 end_seq)
{
if (!after(seq, sp->end_seq) && !after(sp->start_seq, end_seq)) {
if (before(seq, sp->start_seq))
return 0;
}
-static inline void tcp_dsack_set(struct tcp_sock *tp, u32 seq, u32 end_seq)
+static void tcp_dsack_set(struct tcp_sock *tp, u32 seq, u32 end_seq)
{
if (tp->rx_opt.sack_ok && sysctl_tcp_dsack) {
if (before(seq, tp->rcv_nxt))
}
}
-static inline void tcp_dsack_extend(struct tcp_sock *tp, u32 seq, u32 end_seq)
+static void tcp_dsack_extend(struct tcp_sock *tp, u32 seq, u32 end_seq)
{
if (!tp->rx_opt.dsack)
tcp_dsack_set(tp, seq, end_seq);
}
}
-static __inline__ void tcp_sack_swap(struct tcp_sack_block *sack1, struct tcp_sack_block *sack2)
+static inline void tcp_sack_swap(struct tcp_sack_block *sack1, struct tcp_sack_block *sack2)
{
__u32 tmp;
tp->snd_cwnd_stamp = tcp_time_stamp;
}
-static inline int tcp_should_expand_sndbuf(struct sock *sk, struct tcp_sock *tp)
+static int tcp_should_expand_sndbuf(struct sock *sk, struct tcp_sock *tp)
{
/* If the user specified a specific send buffer setting, do
* not modify it.
sk->sk_write_space(sk);
}
-static inline void tcp_check_space(struct sock *sk)
+static void tcp_check_space(struct sock *sk)
{
if (sock_flag(sk, SOCK_QUEUE_SHRUNK)) {
sock_reset_flag(sk, SOCK_QUEUE_SHRUNK);
}
}
-static __inline__ void tcp_data_snd_check(struct sock *sk, struct tcp_sock *tp)
+static inline void tcp_data_snd_check(struct sock *sk, struct tcp_sock *tp)
{
tcp_push_pending_frames(sk, tp);
tcp_check_space(sk);
}
}
-static __inline__ void tcp_ack_snd_check(struct sock *sk)
+static inline void tcp_ack_snd_check(struct sock *sk)
{
if (!inet_csk_ack_scheduled(sk)) {
/* We sent a data segment already. */
return result;
}
-static __inline__ int
-tcp_checksum_complete_user(struct sock *sk, struct sk_buff *skb)
+static inline int tcp_checksum_complete_user(struct sock *sk, struct sk_buff *skb)
{
return skb->ip_summed != CHECKSUM_UNNECESSARY &&
__tcp_checksum_complete_user(sk, skb);
struct tcphdr *th, unsigned len)
{
struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
int saved_clamp = tp->rx_opt.mss_clamp;
tcp_parse_options(skb, &tp->rx_opt, 0);
if (th->ack) {
- struct inet_connection_sock *icsk;
/* rfc793:
* "If the state is SYN-SENT then
* first check the ACK bit
if (tp->rx_opt.sack_ok && sysctl_tcp_fack)
tp->rx_opt.sack_ok |= 2;
- tcp_sync_mss(sk, tp->pmtu_cookie);
+ tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
tcp_initialize_rcv_mss(sk);
/* Remember, tcp_poll() does not lock socket!
tcp_set_state(sk, TCP_ESTABLISHED);
/* Make sure socket is routed, for correct metrics. */
- tp->af_specific->rebuild_header(sk);
+ icsk->icsk_af_ops->rebuild_header(sk);
tcp_init_metrics(sk);
sk_wake_async(sk, 0, POLL_OUT);
}
- icsk = inet_csk(sk);
-
if (sk->sk_write_pending ||
icsk->icsk_accept_queue.rskq_defer_accept ||
icsk->icsk_ack.pingpong) {
if (tp->ecn_flags&TCP_ECN_OK)
sock_set_flag(sk, SOCK_NO_LARGESEND);
- tcp_sync_mss(sk, tp->pmtu_cookie);
+ tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
tcp_initialize_rcv_mss(sk);
struct tcphdr *th, unsigned len)
{
struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
int queued = 0;
tp->rx_opt.saw_tstamp = 0;
goto discard;
if(th->syn) {
- if(tp->af_specific->conn_request(sk, skb) < 0)
+ if (icsk->icsk_af_ops->conn_request(sk, skb) < 0)
return 1;
/* Now we have several options: In theory there is
/* Make sure socket is routed, for
* correct metrics.
*/
- tp->af_specific->rebuild_header(sk);
+ icsk->icsk_af_ops->rebuild_header(sk);
tcp_init_metrics(sk);
EXPORT_SYMBOL(tcp_parse_options);
EXPORT_SYMBOL(tcp_rcv_established);
EXPORT_SYMBOL(tcp_rcv_state_process);
+EXPORT_SYMBOL(tcp_initialize_rcv_mss);