1) Allow a chunk to track the cwnd it was at when sent.

2) Add separate max-bursts for retransmit and hb. These
   are set to sysctlable values but not settable via the
   socket api. This makes sure we don't blast out HB's or
   fast-retransmits.
3) Determine on the first data transmission on a net if
   its local-lan (by being under or over a RTT). This
   can later be used to think about different algorithms
   based on locallan vs big-i (experimental)
4) The cwnd should NOT be allowed to grow when an ECNEcho
   is seen (TCP has this same bug). We fix this in SCTP
   so an ECNe being seen prevents an advance of cwnd.
5) CWR's should not be sent multiple times to the
   same network, instead just updating the TSN being
   transmitted if needed.

MFC after:	1 Month

1 files changed, 12 insertions, 8 deletions

diff --git a/sys/netinet/sctp_indata.c b/sys/netinet/sctp_indata.c
index a6f8d25..186640d 100644
--- a/sys/netinet/sctp_indata.c
+++ b/sys/netinet/sctp_indata.c
@@ -2955,7 +2955,8 @@ sctp_process_segment_range(struct sctp_tcb *stcb, struct sctp_tmit_chunk **p_tp1
 								    &stcb->asoc,
 								    tp1->whoTo,
 								    &tp1->sent_rcv_time,
-								    sctp_align_safe_nocopy);
+								    sctp_align_safe_nocopy,
+								    SCTP_DETERMINE_LL_OK);
 								tp1->do_rtt = 0;
 							}
 						}
@@ -3751,7 +3752,7 @@ sctp_window_probe_recovery(struct sctp_tcb *stcb,
 
 void
 sctp_express_handle_sack(struct sctp_tcb *stcb, uint32_t cumack,
-    uint32_t rwnd, int *abort_now)
+    uint32_t rwnd, int *abort_now, int ecne_seen)
 {
 	struct sctp_nets *net;
 	struct sctp_association *asoc;
@@ -3902,7 +3903,8 @@ sctp_express_handle_sack(struct sctp_tcb *stcb, uint32_t cumack,
 							    sctp_calculate_rto(stcb,
 							    asoc, tp1->whoTo,
 							    &tp1->sent_rcv_time,
-							    sctp_align_safe_nocopy);
+							    sctp_align_safe_nocopy,
+							    SCTP_DETERMINE_LL_OK);
 							tp1->do_rtt = 0;
 						}
 					}
@@ -3994,7 +3996,7 @@ sctp_express_handle_sack(struct sctp_tcb *stcb, uint32_t cumack,
 	}
 
 	/* JRS - Use the congestion control given in the CC module */
-	if (asoc->last_acked_seq != cumack)
+	if ((asoc->last_acked_seq != cumack) && (ecne_seen == 0))
 		asoc->cc_functions.sctp_cwnd_update_after_sack(stcb, asoc, 1, 0, 0);
 
 	asoc->last_acked_seq = cumack;
@@ -4240,7 +4242,7 @@ sctp_handle_sack(struct mbuf *m, int offset_seg, int offset_dup,
     struct sctp_tcb *stcb, struct sctp_nets *net_from,
     uint16_t num_seg, uint16_t num_nr_seg, uint16_t num_dup,
     int *abort_now, uint8_t flags,
-    uint32_t cum_ack, uint32_t rwnd)
+    uint32_t cum_ack, uint32_t rwnd, int ecne_seen)
 {
 	struct sctp_association *asoc;
 	struct sctp_tmit_chunk *tp1, *tp2;
@@ -4500,7 +4502,8 @@ sctp_handle_sack(struct mbuf *m, int offset_seg, int offset_dup,
 							    sctp_calculate_rto(stcb,
 							    asoc, tp1->whoTo,
 							    &tp1->sent_rcv_time,
-							    sctp_align_safe_nocopy);
+							    sctp_align_safe_nocopy,
+							    SCTP_DETERMINE_LL_OK);
 							tp1->do_rtt = 0;
 						}
 					}
@@ -4754,7 +4757,8 @@ sctp_handle_sack(struct mbuf *m, int offset_seg, int offset_dup,
 		asoc->saw_sack_with_nr_frags = 0;
 
 	/* JRS - Use the congestion control given in the CC module */
-	asoc->cc_functions.sctp_cwnd_update_after_sack(stcb, asoc, accum_moved, reneged_all, will_exit_fast_recovery);
+	if (ecne_seen == 0)
+		asoc->cc_functions.sctp_cwnd_update_after_sack(stcb, asoc, accum_moved, reneged_all, will_exit_fast_recovery);
 
 	if (TAILQ_EMPTY(&asoc->sent_queue)) {
 		/* nothing left in-flight */
@@ -5077,7 +5081,7 @@ sctp_update_acked(struct sctp_tcb *stcb, struct sctp_shutdown_chunk *cp,
 	a_rwnd = stcb->asoc.peers_rwnd + stcb->asoc.total_flight;
 
 	/* Now call the express sack handling */
-	sctp_express_handle_sack(stcb, cum_ack, a_rwnd, abort_flag);
+	sctp_express_handle_sack(stcb, cum_ack, a_rwnd, abort_flag, 0);
 }
 
 static void