diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/dccp/ccids/ccid3.c | 89 |
1 files changed, 52 insertions, 37 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index 22a07248c240..bd353044c547 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -121,12 +121,15 @@ static inline void ccid3_update_send_time(struct ccid3_hc_tx_sock *hctx) /* * Update X by * If (p > 0) - * x_calc = calcX(s, R, p); + * X_calc = calcX(s, R, p); * X = max(min(X_calc, 2 * X_recv), s / t_mbi); * Else * If (now - tld >= R) * X = max(min(2 * X, 2 * X_recv), s / R); * tld = now; + * + * If X has changed, we also update the scheduled send time t_now, + * the inter-packet interval t_ipi, and the delta value. */ static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now) @@ -413,10 +416,8 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) struct dccp_tx_hist_entry *packet; struct timeval now; unsigned long t_nfb; - u32 t_elapsed; u32 pinv; - u32 x_recv; - u32 r_sample; + long r_sample, t_elapsed; BUG_ON(hctx == NULL); @@ -427,31 +428,51 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) opt_recv = &hctx->ccid3hctx_options_received; - t_elapsed = dp->dccps_options_received.dccpor_elapsed_time * 10; - x_recv = opt_recv->ccid3or_receive_rate; - pinv = opt_recv->ccid3or_loss_event_rate; - switch (hctx->ccid3hctx_state) { case TFRC_SSTATE_NO_FBACK: case TFRC_SSTATE_FBACK: - /* Calculate new round trip sample by - * R_sample = (now - t_recvdata) - t_delay */ - /* get t_recvdata from history */ + /* get packet from history to look up t_recvdata */ packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist, DCCP_SKB_CB(skb)->dccpd_ack_seq); if (unlikely(packet == NULL)) { - DCCP_WARN("%s, sk=%p, seqno %llu(%s) does't exist " + DCCP_WARN("%s(%p), seqno %llu(%s) doesn't exist " "in history!\n", dccp_role(sk), sk, (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq, dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); return; } - /* Update RTT */ + /* Update receive rate */ + hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate; + + /* Update loss event rate */ + pinv = opt_recv->ccid3or_loss_event_rate; + if (pinv == ~0U || pinv == 0) + hctx->ccid3hctx_p = 0; + else { + hctx->ccid3hctx_p = 1000000 / pinv; + + if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) { + hctx->ccid3hctx_p = TFRC_SMALLEST_P; + ccid3_pr_debug("%s, sk=%p, Smallest p used!\n", + dccp_role(sk), sk); + } + } + dccp_timestamp(sk, &now); - r_sample = timeval_delta(&now, &packet->dccphtx_tstamp); - if (unlikely(r_sample <= t_elapsed)) - DCCP_WARN("r_sample=%uus,t_elapsed=%uus\n", + + /* + * Calculate new round trip sample as per [RFC 3448, 4.3] by + * R_sample = (now - t_recvdata) - t_elapsed + */ + r_sample = timeval_delta(&now, &packet->dccphtx_tstamp); + t_elapsed = dp->dccps_options_received.dccpor_elapsed_time * 10; + + if (unlikely(r_sample <= 0)) { + DCCP_WARN("WARNING: R_sample (%ld) <= 0!\n", r_sample); + r_sample = 0; + } else if (unlikely(r_sample <= t_elapsed)) + DCCP_WARN("WARNING: r_sample=%ldus <= t_elapsed=%ldus\n", r_sample, t_elapsed); else r_sample -= t_elapsed; @@ -474,31 +495,25 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) hctx->ccid3hctx_t_ld = now; ccid3_update_send_time(hctx); - ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); - } else { - hctx->ccid3hctx_rtt = (hctx->ccid3hctx_rtt * 9) / 10 + - r_sample / 10; - ccid3_hc_tx_update_x(sk, &now); - } - ccid3_pr_debug("%s, sk=%p, New RTT estimate=%uus, " - "r_sample=%us\n", dccp_role(sk), sk, - hctx->ccid3hctx_rtt, r_sample); + ccid3_pr_debug("%s(%p), s=%u, w_init=%u, " + "R_sample=%ldus, X=%u\n", dccp_role(sk), + sk, hctx->ccid3hctx_s, w_init, r_sample, + hctx->ccid3hctx_x); - /* Update receive rate */ - hctx->ccid3hctx_x_recv = x_recv;/* X_recv in bytes per sec */ + ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); + } else { + hctx->ccid3hctx_rtt = (9 * hctx->ccid3hctx_rtt + + (u32)r_sample ) / 10; - /* Update loss event rate */ - if (pinv == ~0 || pinv == 0) - hctx->ccid3hctx_p = 0; - else { - hctx->ccid3hctx_p = 1000000 / pinv; + ccid3_hc_tx_update_x(sk, &now); - if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) { - hctx->ccid3hctx_p = TFRC_SMALLEST_P; - ccid3_pr_debug("%s, sk=%p, Smallest p used!\n", - dccp_role(sk), sk); - } + ccid3_pr_debug("%s(%p), RTT=%uus (sample=%ldus), s=%u, " + "p=%u, X_calc=%u, X=%u\n", dccp_role(sk), + sk, hctx->ccid3hctx_rtt, r_sample, + hctx->ccid3hctx_s, hctx->ccid3hctx_p, + hctx->ccid3hctx_x_calc, + hctx->ccid3hctx_x); } /* unschedule no feedback timer */ |