From: Signed-off-by: Xufeng Zhang <xufeng.zh...@windriver.com>
Currently retransmitted DATA chunks could also be used for
RTT measurements since there are no flag to identify whether
the transmitted DATA chunk is a new one or a retransmitted one.
This problem is introduced by commit ae19c5486 ("sctp: remove
'resent' bit from the chunk") which inappropriately removed the
'resent' bit completely, instead of doing this, we should set
the resent bit only for the retransmitted DATA chunks.
Signed-off-by: Xufeng Zhang <xufeng.zh...@windriver.com>
---
include/net/sctp/structs.h | 1 +
net/sctp/output.c | 23 +++++++++++++----------
net/sctp/outqueue.c | 3 +++
net/sctp/sm_make_chunk.c | 1 +
4 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 2174d8d..ea0ca5f 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -629,6 +629,7 @@ struct sctp_chunk {
#define SCTP_NEED_FRTX 0x1
#define SCTP_DONT_FRTX 0x2
__u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
+ resent:1, /* Has this chunk ever been resent. */
has_tsn:1, /* Does this chunk have a TSN yet? */
has_ssn:1, /* Does this chunk have a SSN yet? */
singleton:1, /* Only chunk in the packet? */
diff --git a/net/sctp/output.c b/net/sctp/output.c
index e650978..32c214d 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -467,17 +467,20 @@ int sctp_packet_transmit(struct sctp_packet *packet)
list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
list_del_init(&chunk->list);
if (sctp_chunk_is_data(chunk)) {
- /* 6.3.1 C4) When data is in flight and when allowed
- * by rule C5, a new RTT measurement MUST be made each
- * round trip. Furthermore, new RTT measurements
- * SHOULD be made no more than once per round-trip
- * for a given destination transport address.
- */
-
- if (!tp->rto_pending) {
- chunk->rtt_in_progress = 1;
- tp->rto_pending = 1;
+ if (!chunk->resent) {
+ /* 6.3.1 C4) When data is in flight and when
allowed
+ * by rule C5, a new RTT measurement MUST be
made each
+ * round trip. Furthermore, new RTT
measurements
+ * SHOULD be made no more than once per
round-trip
+ * for a given destination transport address.
+ */
+
+ if (!tp->rto_pending) {
+ chunk->rtt_in_progress = 1;
+ tp->rto_pending = 1;
+ }
}
+
has_data = 1;
}
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 94df758..70f4f56 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -446,6 +446,8 @@ 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.
*/
@@ -1375,6 +1377,7 @@ static void sctp_check_transmitted(struct sctp_outq *q,
* instance).
*/
if (!tchunk->tsn_gap_acked &&
+ !tchunk->resent &&
tchunk->rtt_in_progress) {
tchunk->rtt_in_progress = 0;
rtt = jiffies - tchunk->sent_at;
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index fe69032..8fe89f8 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1321,6 +1321,7 @@ struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
INIT_LIST_HEAD(&retval->list);
retval->skb = skb;
retval->asoc = (struct sctp_association *)asoc;
+ retval->resent = 0;
retval->singleton = 1;
retval->fast_retransmit = SCTP_CAN_FRTX;
--
1.7.0.2
--
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