Author: rrs Date: Sun Jul 14 16:05:47 2019 New Revision: 349987 URL: https://svnweb.freebsd.org/changeset/base/349987
Log: This is the second in a number of patches needed to get BBRv1 into the tree. This fixes the DSACK bug but is also needed by BBR. We have yet to go two more one will be for the pacing code (tcp_ratelimit.c) and the second will be for the new updated LRO code that allows a transport to know the arrival times of packets and (tcp_lro.c). After that we should finally be able to get BBRv1 into head. Sponsored by: Netflix Inc Differential Revision: https://reviews.freebsd.org/D20908 Modified: head/sys/netinet/tcp_output.c head/sys/netinet/tcp_sack.c head/sys/netinet/tcp_stacks/rack.c head/sys/netinet/tcp_var.h Modified: head/sys/netinet/tcp_output.c ============================================================================== --- head/sys/netinet/tcp_output.c Sun Jul 14 12:04:39 2019 (r349986) +++ head/sys/netinet/tcp_output.c Sun Jul 14 16:05:47 2019 (r349987) @@ -1508,7 +1508,13 @@ timer: if (SEQ_GT(tp->snd_nxt + xlen, tp->snd_max)) tp->snd_max = tp->snd_nxt + xlen; } - + if ((error == 0) && + (TCPS_HAVEESTABLISHED(tp->t_state) && + (tp->t_flags & TF_SACK_PERMIT) && + tp->rcv_numsacks > 0)) { + /* Clean up any DSACK's sent */ + tcp_clean_dsack_blocks(tp); + } if (error) { /* Record the error. */ TCP_LOG_EVENT(tp, NULL, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, Modified: head/sys/netinet/tcp_sack.c ============================================================================== --- head/sys/netinet/tcp_sack.c Sun Jul 14 12:04:39 2019 (r349986) +++ head/sys/netinet/tcp_sack.c Sun Jul 14 16:05:47 2019 (r349987) @@ -279,6 +279,45 @@ tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_sta tp->rcv_numsacks = num_head + num_saved; } +void +tcp_clean_dsack_blocks(struct tcpcb *tp) +{ + struct sackblk saved_blks[MAX_SACK_BLKS]; + int num_saved, i; + + INP_WLOCK_ASSERT(tp->t_inpcb); + /* + * Clean up any DSACK blocks that + * are in our queue of sack blocks. + * + */ + num_saved = 0; + for (i = 0; i < tp->rcv_numsacks; i++) { + tcp_seq start = tp->sackblks[i].start; + tcp_seq end = tp->sackblks[i].end; + if (SEQ_GEQ(start, end) || SEQ_LEQ(start, tp->rcv_nxt)) { + /* + * Discard this D-SACK block. + */ + continue; + } + /* + * Save this SACK block. + */ + saved_blks[num_saved].start = start; + saved_blks[num_saved].end = end; + num_saved++; + } + if (num_saved > 0) { + /* + * Copy the saved SACK blocks back. + */ + bcopy(saved_blks, &tp->sackblks[0], + sizeof(struct sackblk) * num_saved); + } + tp->rcv_numsacks = num_saved; +} + /* * Delete all receiver-side SACK information. */ Modified: head/sys/netinet/tcp_stacks/rack.c ============================================================================== --- head/sys/netinet/tcp_stacks/rack.c Sun Jul 14 12:04:39 2019 (r349986) +++ head/sys/netinet/tcp_stacks/rack.c Sun Jul 14 16:05:47 2019 (r349987) @@ -5087,9 +5087,8 @@ rack_do_fastnewdata(struct mbuf *m, struct tcphdr *th, /* Clean receiver SACK report if present */ -/* if (tp->rcv_numsacks) + if (tp->rcv_numsacks) tcp_clean_sackreport(tp); -*/ TCPSTAT_INC(tcps_preddat); tp->rcv_nxt += tlen; /* @@ -8537,10 +8536,10 @@ out: * retransmit. In persist state, just set snd_max. */ if (error == 0) { -/* if (TCPS_HAVEESTABLISHED(tp->t_state) && + if (TCPS_HAVEESTABLISHED(tp->t_state) && (tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) - tcp_clean_dsack_blocks(tp);*/ + tcp_clean_dsack_blocks(tp); if (len == 0) counter_u64_add(rack_out_size[TCP_MSS_ACCT_SNDACK], 1); else if (len == 1) { Modified: head/sys/netinet/tcp_var.h ============================================================================== --- head/sys/netinet/tcp_var.h Sun Jul 14 12:04:39 2019 (r349986) +++ head/sys/netinet/tcp_var.h Sun Jul 14 16:05:47 2019 (r349987) @@ -939,6 +939,7 @@ tcp_seq tcp_new_isn(struct in_conninfo *); int tcp_sack_doack(struct tcpcb *, struct tcpopt *, tcp_seq); void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend); +void tcp_clean_dsack_blocks(struct tcpcb *tp); void tcp_clean_sackreport(struct tcpcb *tp); void tcp_sack_adjust(struct tcpcb *tp); struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
