X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=net%2Fipv4%2Ftcp_input.c;h=bf2e23086bcead8b15e02d2a63f1194a40c72093;hb=c8a4f06e4b27dba425ed49fa603d9257e4cd9ece;hp=4cb5e6f408dcf4b060370d5896baf0f44ccea351;hpb=9772efb970780aeed488c19d8b4afd46c3b484af;p=powerpc.git diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 4cb5e6f408..bf2e23086b 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -42,7 +42,7 @@ * Andi Kleen : Moved open_request checking here * and process RSTs for open_requests. * Andi Kleen : Better prune_queue, and other fixes. - * Andrey Savochkin: Fix RTT measurements in the presnce of + * Andrey Savochkin: Fix RTT measurements in the presence of * timestamps. * Andrey Savochkin: Check sequence numbers correctly when * removing SACKs due to in sequence incoming @@ -224,7 +224,7 @@ static void tcp_fixup_sndbuf(struct sock *sk) * of receiver window. Check #2. * * The scheme does not work when sender sends good segments opening - * window and then starts to feed us spagetti. But it should work + * window and then starts to feed us spaghetti. But it should work * in common situations. Otherwise, we have to rely on queue collapsing. */ @@ -234,7 +234,7 @@ static int __tcp_grow_window(const struct sock *sk, struct tcp_sock *tp, { /* Optimize this! */ int truesize = tcp_win_from_space(skb->truesize)/2; - int window = tcp_full_space(sk)/2; + int window = tcp_win_from_space(sysctl_tcp_rmem[2])/2; while (tp->rcv_ssthresh <= window) { if (truesize <= skb->len) @@ -278,7 +278,7 @@ static void tcp_fixup_rcvbuf(struct sock *sk) int rcvmem = tp->advmss + MAX_TCP_HEADER + 16 + sizeof(struct sk_buff); /* Try to select rcvbuf so that 4 mss-sized segments - * will fit to window and correspoding skbs will fit to our rcvbuf. + * will fit to window and corresponding skbs will fit to our rcvbuf. * (was 3; 4 is minimum to allow fast retransmit to work.) */ while (tcp_win_from_space(rcvmem) < tp->advmss) @@ -287,7 +287,7 @@ static void tcp_fixup_rcvbuf(struct sock *sk) sk->sk_rcvbuf = min(4 * rcvmem, sysctl_tcp_rmem[2]); } -/* 4. Try to fixup all. It is made iimediately after connection enters +/* 4. Try to fixup all. It is made immediately after connection enters * established state. */ static void tcp_init_buffer_space(struct sock *sk) @@ -327,37 +327,18 @@ static void tcp_init_buffer_space(struct sock *sk) static void tcp_clamp_window(struct sock *sk, struct tcp_sock *tp) { struct inet_connection_sock *icsk = inet_csk(sk); - struct sk_buff *skb; - unsigned int app_win = tp->rcv_nxt - tp->copied_seq; - int ofo_win = 0; icsk->icsk_ack.quick = 0; - skb_queue_walk(&tp->out_of_order_queue, skb) { - ofo_win += skb->len; - } - - /* If overcommit is due to out of order segments, - * do not clamp window. Try to expand rcvbuf instead. - */ - if (ofo_win) { - if (sk->sk_rcvbuf < sysctl_tcp_rmem[2] && - !(sk->sk_userlocks & SOCK_RCVBUF_LOCK) && - !tcp_memory_pressure && - atomic_read(&tcp_memory_allocated) < sysctl_tcp_mem[0]) - sk->sk_rcvbuf = min(atomic_read(&sk->sk_rmem_alloc), - sysctl_tcp_rmem[2]); + if (sk->sk_rcvbuf < sysctl_tcp_rmem[2] && + !(sk->sk_userlocks & SOCK_RCVBUF_LOCK) && + !tcp_memory_pressure && + atomic_read(&tcp_memory_allocated) < sysctl_tcp_mem[0]) { + sk->sk_rcvbuf = min(atomic_read(&sk->sk_rmem_alloc), + sysctl_tcp_rmem[2]); } - if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) { - app_win += ofo_win; - if (atomic_read(&sk->sk_rmem_alloc) >= 2 * sk->sk_rcvbuf) - app_win >>= 1; - if (app_win > icsk->icsk_ack.rcv_mss) - app_win -= icsk->icsk_ack.rcv_mss; - app_win = max(app_win, 2U*tp->advmss); - + if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) tp->rcv_ssthresh = min(tp->window_clamp, 2U*tp->advmss); - } } /* Receiver "autotuning" code. @@ -386,8 +367,8 @@ static void tcp_rcv_rtt_update(struct tcp_sock *tp, u32 sample, int win_dep) * are stalled on filesystem I/O. * * Also, since we are only going for a minimum in the - * non-timestamp case, we do not smoothe things out - * else with timestamps disabled convergance takes too + * non-timestamp case, we do not smooth things out + * else with timestamps disabled convergence takes too * long. */ if (!win_dep) { @@ -396,7 +377,7 @@ static void tcp_rcv_rtt_update(struct tcp_sock *tp, u32 sample, int win_dep) } else if (m < new_sample) new_sample = m << 3; } else { - /* No previous mesaure. */ + /* No previous measure. */ new_sample = m << 3; } @@ -525,7 +506,7 @@ static void tcp_event_data_recv(struct sock *sk, struct tcp_sock *tp, struct sk_ if (icsk->icsk_ack.ato > icsk->icsk_rto) icsk->icsk_ack.ato = icsk->icsk_rto; } else if (m > icsk->icsk_rto) { - /* Too long gap. Apparently sender falled to + /* Too long gap. Apparently sender failed to * restart window, so that we send ACKs quickly. */ tcp_incr_quickack(sk); @@ -565,7 +546,7 @@ static void tcp_rtt_estimator(struct sock *sk, const __u32 mrtt) * * Funny. This algorithm seems to be very broken. * These formulae increase RTO, when it should be decreased, increase - * too slowly, when it should be incresed 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) @@ -626,14 +607,14 @@ static inline void tcp_set_rto(struct sock *sk) * at least by solaris and freebsd. "Erratic ACKs" has _nothing_ * to do with delayed acks, because at cwnd>2 true delack timeout * is invisible. Actually, Linux-2.4 also generates erratic - * ACKs in some curcumstances. + * ACKs in some circumstances. */ inet_csk(sk)->icsk_rto = (tp->srtt >> 3) + tp->rttvar; /* 2. Fixups made earlier cannot be right. * If we do not estimate RTO correctly without them, * all the algo is pure shit and should be replaced - * with correct one. It is exaclty, which we pretend to do. + * with correct one. It is exactly, which we pretend to do. */ } @@ -791,7 +772,7 @@ static void tcp_init_metrics(struct sock *sk) * to make it more realistic. * * A bit of theory. RTT is time passed after "normal" sized packet - * is sent until it is ACKed. In normal curcumstances sending small + * is sent until it is ACKed. In normal circumstances sending small * packets force peer to delay ACKs and calculation is correct too. * The algorithm is adaptive and, provided we follow specs, it * NEVER underestimate RTT. BUT! If peer tries to make some clever @@ -916,18 +897,32 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ 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; istart_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) { @@ -959,15 +954,58 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ 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; istart_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. */ @@ -1042,6 +1080,9 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ 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, @@ -1054,6 +1095,9 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ 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; } } @@ -1077,6 +1121,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ (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; } } } @@ -1104,6 +1149,9 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ 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; @@ -1211,6 +1259,8 @@ static void tcp_enter_frto_loss(struct sock *sk) 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) @@ -1277,6 +1327,8 @@ void tcp_enter_loss(struct sock *sk, int how) 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) @@ -1501,17 +1553,37 @@ static void tcp_mark_head_lost(struct sock *sk, struct tcp_sock *tp, 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); @@ -1538,13 +1610,28 @@ static void tcp_update_scoreboard(struct sock *sk, struct tcp_sock *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); } } @@ -1624,6 +1711,10 @@ static void tcp_undo_cwr(struct sock *sk, const int undo) } 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) @@ -1707,6 +1798,9 @@ static int tcp_try_undo_loss(struct sock *sk, 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; @@ -1918,7 +2012,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una, } /* Read draft-ietf-tcplw-high-performance before mucking - * with this code. (Superceeds RFC1323) + * with this code. (Supersedes RFC1323) */ static void tcp_ack_saw_tstamp(struct sock *sk, int flag) { @@ -1931,7 +2025,7 @@ static void tcp_ack_saw_tstamp(struct sock *sk, int flag) * 1998/04/10 Andrey V. Savochkin * * Changed: reset backoff as soon as we see the first valid sample. - * If we do not, we get strongly overstimated rto. With timestamps + * If we do not, we get strongly overestimated rto. With timestamps * samples are accepted even from very old segments: f.e., when rtt=1 * increases to 8, we retransmit 5 times and after 8 seconds delayed * answer arrives rto becomes 120 seconds! If at least one of segments @@ -2136,6 +2230,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) 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) { @@ -2287,7 +2382,7 @@ static void tcp_process_frto(struct sock *sk, u32 prior_snd_una) } /* F-RTO affects on two new ACKs following RTO. - * At latest on third ACK the TCP behavor is back to normal. + * At latest on third ACK the TCP behavior is back to normal. */ tp->frto_counter = (tp->frto_counter + 1) % 3; } @@ -2363,7 +2458,7 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag) tcp_process_frto(sk, prior_snd_una); if (tcp_ack_is_dubious(sk, flag)) { - /* Advanve CWND, if state allows this. */ + /* Advance CWND, if state allows this. */ if ((flag & FLAG_DATA_ACKED) && tcp_may_raise_cwnd(sk, flag)) tcp_cong_avoid(sk, ack, seq_rtt, prior_in_flight, 0); tcp_fastretrans_alert(sk, prior_snd_una, prior_packets, flag); @@ -3152,7 +3247,7 @@ tcp_collapse(struct sock *sk, struct sk_buff_head *list, { struct sk_buff *skb; - /* First, check that queue is collapsable and find + /* First, check that queue is collapsible and find * the point where collapsing can be useful. */ for (skb = head; skb != tail; ) { /* No new bits? It is possible on ofo queue. */ @@ -3460,7 +3555,7 @@ static __inline__ void tcp_ack_snd_check(struct sock *sk) /* * This routine is only called when we have urgent data - * signalled. Its the 'slow' part of tcp_urg. It could be + * signaled. Its the 'slow' part of tcp_urg. It could be * moved inline now as tcp_urg is only called from one * place. We handle URGent data wrong. We have to - as * BSD still doesn't use the correction from RFC961. @@ -3505,7 +3600,7 @@ static void tcp_check_urg(struct sock * sk, struct tcphdr * th) * urgent. To do this requires some care. We cannot just ignore * tp->copied_seq since we would read the last urgent byte again * as data, nor can we alter copied_seq until this data arrives - * or we break the sematics of SIOCATMARK (and thus sockatmark()) + * or we break the semantics of SIOCATMARK (and thus sockatmark()) * * NOTE. Double Dutch. Rendering to plain English: author of comment * above did something sort of send("A", MSG_OOB); send("B", MSG_OOB); @@ -3650,7 +3745,7 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb, tp->rx_opt.saw_tstamp = 0; /* pred_flags is 0xS?10 << 16 + snd_wnd - * if header_predition is to be made + * if header_prediction is to be made * 'S' will always be tp->tcp_header_len >> 2 * '?' will be 0 for the fast path, otherwise pred_flags is 0 to * turn it off (when there are holes in the receive