diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/dccp/ccids/ccid3.c | 60 |
1 files changed, 41 insertions, 19 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index 577fd0ef84e5..05513f3df652 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -159,6 +159,25 @@ static void ccid3_hc_tx_update_x(struct sock *sk) ccid3_update_send_time(hctx); } +/* + * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) + * @len: DCCP packet payload size in bytes + */ +static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) +{ + if (unlikely(len == 0)) + ccid3_pr_debug("Packet payload length is 0 - not updating\n"); + else + hctx->ccid3hctx_s = hctx->ccid3hctx_s == 0 ? len : + (9 * hctx->ccid3hctx_s + len) / 10; + /* + * Note: We could do a potential optimisation here - when `s' changes, + * recalculate sending rate and consequently t_ipi, t_delta, and + * t_now. This is however non-standard, and the benefits are not + * clear, so it is currently left out. + */ +} + static void ccid3_hc_tx_no_feedback_timer(unsigned long data) { struct sock *sk = (struct sock *)data; @@ -299,6 +318,10 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, hctx->ccid3hctx_t_last_win_count = now; ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); + /* Set initial sending rate to 1 packet per second */ + ccid3_hc_tx_update_s(hctx, len); + hctx->ccid3hctx_x = hctx->ccid3hctx_s; + /* First timeout, according to [RFC 3448, 4.2], is 1 second */ hctx->ccid3hctx_t_ipi = USEC_PER_SEC; /* Initial delta: minimum of 0.5 sec and t_gran/2 */ @@ -350,6 +373,8 @@ static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len) unsigned long quarter_rtt; struct dccp_tx_hist_entry *packet; + ccid3_hc_tx_update_s(hctx, len); + packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); if (unlikely(packet == NULL)) { DCCP_WARN("packet doesn't exist in history!\n"); @@ -594,17 +619,9 @@ static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid); - if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && - dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) - hctx->ccid3hctx_s = dp->dccps_packet_size; - else - hctx->ccid3hctx_s = TFRC_STD_PACKET_SIZE; - - /* Set transmission rate to 1 packet per second */ - hctx->ccid3hctx_x = hctx->ccid3hctx_s; + hctx->ccid3hctx_s = 0; hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; INIT_LIST_HEAD(&hctx->ccid3hctx_hist); @@ -658,6 +675,15 @@ static void ccid3_hc_rx_set_state(struct sock *sk, hcrx->ccid3hcrx_state = state; } +static inline void ccid3_hc_rx_update_s(struct ccid3_hc_rx_sock *hcrx, int len) +{ + if (unlikely(len == 0)) /* don't update on empty packets (e.g. ACKs) */ + ccid3_pr_debug("Packet payload length is 0 - not updating\n"); + else + hcrx->ccid3hcrx_s = hcrx->ccid3hcrx_s == 0 ? len : + (9 * hcrx->ccid3hcrx_s + len) / 10; +} + static void ccid3_hc_rx_send_feedback(struct sock *sk) { struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); @@ -934,7 +960,7 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) struct dccp_rx_hist_entry *packet; struct timeval now; u32 p_prev, rtt_prev, r_sample, t_elapsed; - int loss; + int loss, payload_size; BUG_ON(hcrx == NULL); @@ -989,6 +1015,9 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK) return; + payload_size = skb->len - dccp_hdr(skb)->dccph_doff * 4; + ccid3_hc_rx_update_s(hcrx, payload_size); + switch (hcrx->ccid3hcrx_state) { case TFRC_RSTATE_NO_DATA: ccid3_pr_debug("%s, sk=%p(%s), skb=%p, sending initial " @@ -999,8 +1028,7 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); return; case TFRC_RSTATE_DATA: - hcrx->ccid3hcrx_bytes_recv += skb->len - - dccp_hdr(skb)->dccph_doff * 4; + hcrx->ccid3hcrx_bytes_recv += payload_size; if (loss) break; @@ -1040,22 +1068,16 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid); ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); - if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && - dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) - hcrx->ccid3hcrx_s = dp->dccps_packet_size; - else - hcrx->ccid3hcrx_s = TFRC_STD_PACKET_SIZE; - hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist); INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist); dccp_timestamp(sk, &hcrx->ccid3hcrx_tstamp_last_ack); hcrx->ccid3hcrx_tstamp_last_feedback = hcrx->ccid3hcrx_tstamp_last_ack; + hcrx->ccid3hcrx_s = 0; hcrx->ccid3hcrx_rtt = 5000; /* XXX 5ms for now... */ return 0; } |