diff options
| -rw-r--r-- | include/net/sctp/structs.h | 4 | ||||
| -rw-r--r-- | net/sctp/associola.c | 1 | ||||
| -rw-r--r-- | net/sctp/output.c | 23 | ||||
| -rw-r--r-- | net/sctp/outqueue.c | 15 | ||||
| -rw-r--r-- | net/sctp/transport.c | 38 |
5 files changed, 58 insertions, 23 deletions
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index ac794a6823eb..bc3f8d879c5c 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -942,6 +942,8 @@ struct sctp_transport { /* Data that has been sent, but not acknowledged. */ __u32 flight_size; + __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ + /* TSN marking the fast recovery exit point */ __u32 fast_recovery_exit; @@ -1070,6 +1072,8 @@ void sctp_transport_put(struct sctp_transport *); void sctp_transport_update_rto(struct sctp_transport *, __u32); void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t); +void sctp_transport_burst_limited(struct sctp_transport *); +void sctp_transport_burst_reset(struct sctp_transport *); unsigned long sctp_transport_timeout(struct sctp_transport *); void sctp_transport_reset(struct sctp_transport *); void sctp_transport_update_pmtu(struct sctp_transport *, u32); diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 37e982510bea..880dae2ca87b 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -738,6 +738,7 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, peer->partial_bytes_acked = 0; peer->flight_size = 0; + peer->burst_limited = 0; /* Set the transport's RTO.initial value */ peer->rto = asoc->rto_initial; diff --git a/net/sctp/output.c b/net/sctp/output.c index 9e8e0ea844be..b210d2077e28 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -615,7 +615,6 @@ static sctp_xmit_t sctp_packet_can_append_data(struct sctp_packet *packet, sctp_xmit_t retval = SCTP_XMIT_OK; size_t datasize, rwnd, inflight, flight_size; struct sctp_transport *transport = packet->transport; - __u32 max_burst_bytes; struct sctp_association *asoc = transport->asoc; struct sctp_outq *q = &asoc->outqueue; @@ -648,28 +647,6 @@ static sctp_xmit_t sctp_packet_can_append_data(struct sctp_packet *packet, } } - /* sctpimpguide-05 2.14.2 - * D) When the time comes for the sender to - * transmit new DATA chunks, the protocol parameter Max.Burst MUST - * first be applied to limit how many new DATA chunks may be sent. - * The limit is applied by adjusting cwnd as follows: - * if ((flightsize + Max.Burst * MTU) < cwnd) - * cwnd = flightsize + Max.Burst * MTU - */ - max_burst_bytes = asoc->max_burst * asoc->pathmtu; - if ((flight_size + max_burst_bytes) < transport->cwnd) { - transport->cwnd = flight_size + max_burst_bytes; - SCTP_DEBUG_PRINTK("%s: cwnd limited by max_burst: " - "transport: %p, cwnd: %d, " - "ssthresh: %d, flight_size: %d, " - "pba: %d\n", - __func__, transport, - transport->cwnd, - transport->ssthresh, - transport->flight_size, - transport->partial_bytes_acked); - } - /* RFC 2960 6.1 Transmission of DATA Chunks * * B) At any given time, the sender MUST NOT transmit new data diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c index 5732661c87d3..2f2377369e2b 100644 --- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c @@ -931,6 +931,14 @@ static int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout) goto sctp_flush_out; } + /* Apply Max.Burst limitation to the current transport in + * case it will be used for new data. We are going to + * rest it before we return, but we want to apply the limit + * to the currently queued data. + */ + if (transport) + sctp_transport_burst_limited(transport); + /* Finally, transmit new packets. */ while ((chunk = sctp_outq_dequeue_data(q)) != NULL) { /* RFC 2960 6.5 Every DATA chunk MUST carry a valid @@ -976,6 +984,10 @@ static int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout) packet = &transport->packet; sctp_packet_config(packet, vtag, asoc->peer.ecn_capable); + /* We've switched transports, so apply the + * Burst limit to the new transport. + */ + sctp_transport_burst_limited(transport); } SCTP_DEBUG_PRINTK("sctp_outq_flush(%p, %p[%s]), ", @@ -1070,6 +1082,9 @@ sctp_flush_out: packet = &t->packet; if (!sctp_packet_empty(packet)) error = sctp_packet_transmit(packet); + + /* Clear the burst limited state, if any */ + sctp_transport_burst_reset(t); } return error; diff --git a/net/sctp/transport.c b/net/sctp/transport.c index 2df29cbdaf5a..9a6cb22d129f 100644 --- a/net/sctp/transport.c +++ b/net/sctp/transport.c @@ -576,6 +576,43 @@ void sctp_transport_lower_cwnd(struct sctp_transport *transport, transport->cwnd, transport->ssthresh); } +/* Apply Max.Burst limit to the congestion window: + * sctpimpguide-05 2.14.2 + * D) When the time comes for the sender to + * transmit new DATA chunks, the protocol parameter Max.Burst MUST + * first be applied to limit how many new DATA chunks may be sent. + * The limit is applied by adjusting cwnd as follows: + * if ((flightsize+ Max.Burst * MTU) < cwnd) + * cwnd = flightsize + Max.Burst * MTU + */ + +void sctp_transport_burst_limited(struct sctp_transport *t) +{ + struct sctp_association *asoc = t->asoc; + u32 old_cwnd = t->cwnd; + u32 max_burst_bytes; + + if (t->burst_limited) + return; + + max_burst_bytes = t->flight_size + (asoc->max_burst * asoc->pathmtu); + if (max_burst_bytes < old_cwnd) { + t->cwnd = max_burst_bytes; + t->burst_limited = old_cwnd; + } +} + +/* Restore the old cwnd congestion window, after the burst had it's + * desired effect. + */ +void sctp_transport_burst_reset(struct sctp_transport *t) +{ + if (t->burst_limited) { + t->cwnd = t->burst_limited; + t->burst_limited = 0; + } +} + /* What is the next timeout value for this transport? */ unsigned long sctp_transport_timeout(struct sctp_transport *t) { @@ -598,6 +635,7 @@ void sctp_transport_reset(struct sctp_transport *t) * (see Section 6.2.1) */ t->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); + t->burst_limited = 0; t->ssthresh = asoc->peer.i.a_rwnd; t->last_rto = t->rto = asoc->rto_initial; t->rtt = 0; |