sctp: reuse sent_count to avoid retransmitted chunks for RTT measurements

Now sctp uses chunk->resent to record if a chunk is retransmitted, for
RTT measurements with retransmitted DATA chunks. chunk->sent_count was
introduced to record how many times one chunk has been sent for prsctp
RTX policy before. We actually can know if one chunk is retransmitted
by checking chunk->sent_count is greater than 1.

This patch is to remove resent from sctp_chunk and reuse sent_count
to avoid retransmitted chunks for RTT measurements.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 3 deletions

diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 582585393d35..e54082699520 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -507,8 +507,6 @@ void sctp_retransmit_mark(struct sctp_outq *q,
                                 transport->rto_pending = 0;
                         }
 
-                        chunk->resent = 1;
-
                         /* Move the chunk to the retransmit queue. The chunks
                          * on the retransmit queue are always kept in order.
                          */
@@ -1439,7 +1437,7 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                                  * instance).
                                  */
                                 if (!tchunk->tsn_gap_acked &&
-                                    !tchunk->resent &&
+                                    !sctp_chunk_retransmitted(tchunk) &&
                                     tchunk->rtt_in_progress) {
                                         tchunk->rtt_in_progress = 0;
                                         rtt = jiffies - tchunk->sent_at;