aboutsummaryrefslogtreecommitdiffstats
path: root/net/dccp/ccids
diff options
context:
space:
mode:
Diffstat (limited to 'net/dccp/ccids')
-rw-r--r--net/dccp/ccids/ccid2.c46
-rw-r--r--net/dccp/ccids/ccid2.h6
2 files changed, 17 insertions, 35 deletions
diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c
index 4f6c352..02d126d 100644
--- a/net/dccp/ccids/ccid2.c
+++ b/net/dccp/ccids/ccid2.c
@@ -199,9 +199,8 @@ static void ccid2_hc_tx_rto_expire(unsigned long data)
hctx->ccid2hctx_pipe = 0;
/* clear state about stuff we sent */
- hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
- hctx->ccid2hctx_ssacks = 0;
- hctx->ccid2hctx_acks = 0;
+ hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
+ hctx->ccid2hctx_packets_acked = 0;
/* clear ack ratio state. */
hctx->ccid2hctx_rpseq = 0;
@@ -406,31 +405,15 @@ static inline void ccid2_new_ack(struct sock *sk,
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- /* slow start */
if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) {
- hctx->ccid2hctx_acks = 0;
-
- /* We can increase cwnd at most maxincr [ack_ratio/2] */
- if (*maxincr) {
- /* increase every 2 acks */
- hctx->ccid2hctx_ssacks++;
- if (hctx->ccid2hctx_ssacks == 2) {
- hctx->ccid2hctx_cwnd++;
- hctx->ccid2hctx_ssacks = 0;
- *maxincr = *maxincr - 1;
- }
- } else {
- /* increased cwnd enough for this single ack */
- hctx->ccid2hctx_ssacks = 0;
- }
- } else {
- hctx->ccid2hctx_ssacks = 0;
- hctx->ccid2hctx_acks++;
-
- if (hctx->ccid2hctx_acks >= hctx->ccid2hctx_cwnd) {
- hctx->ccid2hctx_cwnd++;
- hctx->ccid2hctx_acks = 0;
+ if (*maxincr > 0 && ++hctx->ccid2hctx_packets_acked == 2) {
+ hctx->ccid2hctx_cwnd += 1;
+ *maxincr -= 1;
+ hctx->ccid2hctx_packets_acked = 0;
}
+ } else if (++hctx->ccid2hctx_packets_acked >= hctx->ccid2hctx_cwnd) {
+ hctx->ccid2hctx_cwnd += 1;
+ hctx->ccid2hctx_packets_acked = 0;
}
/* update RTO */
@@ -596,12 +579,13 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
}
}
- /* If in slow-start, cwnd can increase at most Ack Ratio / 2 packets for
- * this single ack. I round up.
- * -sorbo.
+ /*
+ * In slow-start, cwnd can increase up to a maximum of Ack Ratio/2
+ * packets per acknowledgement. Rounding up avoids that cwnd is not
+ * advanced when Ack Ratio is 1 and gives a slight edge otherwise.
*/
- maxincr = dp->dccps_l_ack_ratio >> 1;
- maxincr++;
+ if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh)
+ maxincr = DIV_ROUND_UP(dp->dccps_l_ack_ratio, 2);
/* go through all ack vectors */
while ((offset = ccid2_ackvector(sk, skb, offset,
diff --git a/net/dccp/ccids/ccid2.h b/net/dccp/ccids/ccid2.h
index 2671f8e..2c94ca0 100644
--- a/net/dccp/ccids/ccid2.h
+++ b/net/dccp/ccids/ccid2.h
@@ -43,8 +43,7 @@ struct ccid2_seq {
/** struct ccid2_hc_tx_sock - CCID2 TX half connection
*
* @ccid2hctx_{cwnd,ssthresh,pipe}: as per RFC 4341, section 5
- * @ccid2hctx_ssacks - ACKs recv in slow start
- * @ccid2hctx_acks - ACKS recv in AI phase
+ * @ccid2hctx_packets_acked - Ack counter for deriving cwnd growth (RFC 3465)
* @ccid2hctx_lastrtt -time RTT was last measured
* @ccid2hctx_rpseq - last consecutive seqno
* @ccid2hctx_rpdupack - dupacks since rpseq
@@ -53,8 +52,7 @@ struct ccid2_hc_tx_sock {
u32 ccid2hctx_cwnd;
u32 ccid2hctx_ssthresh;
u32 ccid2hctx_pipe;
- int ccid2hctx_ssacks;
- int ccid2hctx_acks;
+ u32 ccid2hctx_packets_acked;
struct ccid2_seq *ccid2hctx_seqbuf[CCID2_SEQBUF_MAX];
int ccid2hctx_seqbufc;
struct ccid2_seq *ccid2hctx_seqh;