[PATCH] For for each TSN t being newly acked (Not only cumulatively, but also SELECTIVELY) cacc_saw_newack should be set to 1.

[Chang Xiangzhong <changxiangzhong@gmail.com>]

Signed-off-by: Xiangzhong Chang <changxiangzhong@gmail.com>
---
 net/sctp/outqueue.c |  142 ++++++++++++++++++++++++---------------------------
 1 file changed, 68 insertions(+), 74 deletions(-)

diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 94df758..f10d848 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -1357,84 +1357,78 @@ static void sctp_check_transmitted(struct sctp_outq *q,
 
 		tsn = ntohl(tchunk->subh.data_hdr->tsn);
 		if (sctp_acked(sack, tsn)) {
-			/* If this queue is the retransmit queue, the
-			 * retransmit timer has already reclaimed
-			 * the outstanding bytes for this chunk, so only
-			 * count bytes associated with a transport.
-			 */
-			if (transport) {
-				/* If this chunk is being used for RTT
-				 * measurement, calculate the RTT and update
-				 * the RTO using this value.
-				 *
-				 * 6.3.1 C5) Karn's algorithm: RTT measurements
-				 * MUST NOT be made using packets that were
-				 * retransmitted (and thus for which it is
-				 * ambiguous whether the reply was for the
-				 * first instance of the packet or a later
-				 * instance).
-				 */
-				if (!tchunk->tsn_gap_acked &&
-				    tchunk->rtt_in_progress) {
-					tchunk->rtt_in_progress = 0;
-					rtt = jiffies - tchunk->sent_at;
-					sctp_transport_update_rto(transport,
-								  rtt);
-				}
-			}
-
-			/* If the chunk hasn't been marked as ACKED,
-			 * mark it and account bytes_acked if the
-			 * chunk had a valid transport (it will not
-			 * have a transport if ASCONF had deleted it
-			 * while DATA was outstanding).
-			 */
 			if (!tchunk->tsn_gap_acked) {
-				tchunk->tsn_gap_acked = 1;
-				*highest_new_tsn_in_sack = tsn;
-				bytes_acked += sctp_data_size(tchunk);
-				if (!tchunk->transport)
-					migrate_bytes += sctp_data_size(tchunk);
-				forward_progress = true;
+			    /* If this queue is the retransmit queue, the
+			     * retransmit timer has already reclaimed
+			     * the outstanding bytes for this chunk, so only
+			     * count bytes associated with a transport.
+			     *
+			     * If this chunk is being used for RTT
+			     * measurement, calculate the RTT and update
+			     * the RTO using this value.
+			     *
+			     * 6.3.1 C5) Karn's algorithm: RTT measurements
+			     * MUST NOT be made using packets that were
+			     * retransmitted (and thus for which it is
+			     * ambiguous whether the reply was for the
+			     * first instance of the packet or a later
+			     * instance).
+			     */
+			    if (transport && tchunk->rtt_in_progress) {
+				tchunk->rtt_in_progress = 0;
+				rtt = jiffies - tchunk->sent_at;
+				sctp_transport_update_rto(transport,
+					rtt);
+			    }
+
+			    /* If the chunk hasn't been marked as ACKED,
+			     * mark it and account bytes_acked if the
+			     * chunk had a valid transport (it will not
+			     * have a transport if ASCONF had deleted it
+			     * while DATA was outstanding).
+			     */
+			    tchunk->tsn_gap_acked = 1;
+			    *highest_new_tsn_in_sack = tsn;
+			    bytes_acked += sctp_data_size(tchunk);
+			    if (!tchunk->transport)
+				migrate_bytes += sctp_data_size(tchunk);
+			    forward_progress = true;
+
+			    /*
+			     * SFR-CACC algorithm:
+			     * 2) If the SACK contains gap acks
+			     * and the flag CHANGEOVER_ACTIVE is
+			     * set the receiver of the SACK MUST
+			     * take the following action:
+			     *
+			     * B) For each TSN t being acked that
+			     * has not been acked in any SACK so
+			     * far, set cacc_saw_newack to 1 for
+			     * the destination that the TSN was
+			     * sent to.
+			     */
+			    if (transport &&
+				    sack->num_gap_ack_blocks &&
+				    q->asoc->peer.primary_path->cacc.
+				    changeover_active)
+				transport->cacc.cacc_saw_newack = 1;
 			}
 
 			if (TSN_lte(tsn, sack_ctsn)) {
-				/* RFC 2960  6.3.2 Retransmission Timer Rules
-				 *
-				 * R3) Whenever a SACK is received
-				 * that acknowledges the DATA chunk
-				 * with the earliest outstanding TSN
-				 * for that address, restart T3-rtx
-				 * timer for that address with its
-				 * current RTO.
-				 */
-				restart_timer = 1;
-				forward_progress = true;
-
-				if (!tchunk->tsn_gap_acked) {
-					/*
-					 * SFR-CACC algorithm:
-					 * 2) If the SACK contains gap acks
-					 * and the flag CHANGEOVER_ACTIVE is
-					 * set the receiver of the SACK MUST
-					 * take the following action:
-					 *
-					 * B) For each TSN t being acked that
-					 * has not been acked in any SACK so
-					 * far, set cacc_saw_newack to 1 for
-					 * the destination that the TSN was
-					 * sent to.
-					 */
-					if (transport &&
-					    sack->num_gap_ack_blocks &&
-					    q->asoc->peer.primary_path->cacc.
-					    changeover_active)
-						transport->cacc.cacc_saw_newack
-							= 1;
-				}
-
-				list_add_tail(&tchunk->transmitted_list,
-					      &q->sacked);
+			    /* RFC 2960  6.3.2 Retransmission Timer Rules
+			     *
+			     * R3) Whenever a SACK is received
+			     * that acknowledges the DATA chunk
+			     * with the earliest outstanding TSN
+			     * for that address, restart T3-rtx
+			     * timer for that address with its
+			     * current RTO.
+			     */
+			    restart_timer = 1;
+			    forward_progress = true;
+
+			    list_add_tail(&tchunk->transmitted_list,
+				    &q->sacked);
 			} else {
 				/* RFC2960 7.2.4, sctpimpguide-05 2.8.2
 				 * M2) Each time a SACK arrives reporting
-- 
1.7.9.5