diff options
| -rw-r--r-- | net/dccp/ccids/ccid3.c | 35 |
1 files changed, 12 insertions, 23 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index 26ab73db286..95eca99e4dd 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -82,20 +82,14 @@ static void ccid3_hc_tx_set_state(struct sock *sk, } /* - * Recalculate scheduled nominal send time t_nom, inter-packet interval - * t_ipi, and delta value. Should be called after each change to X. + * Recalculate t_ipi and delta (should be called whenever X changes) */ -static inline void ccid3_update_send_time(struct ccid3_hc_tx_sock *hctx) +static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx) { - timeval_sub_usecs(&hctx->ccid3hctx_t_nom, hctx->ccid3hctx_t_ipi); - /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */ hctx->ccid3hctx_t_ipi = scaled_div(hctx->ccid3hctx_s, hctx->ccid3hctx_x >> 6); - /* Update nominal send time with regard to the new t_ipi */ - timeval_add_usecs(&hctx->ccid3hctx_t_nom, hctx->ccid3hctx_t_ipi); - /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, TFRC_OPSYS_HALF_TIME_GRAN); @@ -119,8 +113,6 @@ static inline void ccid3_update_send_time(struct ccid3_hc_tx_sock *hctx) * fine-grained resolution of sending rates. This requires scaling by 2^6 * throughout the code. Only X_calc is unscaled (in bytes/second). * - * 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) @@ -151,7 +143,7 @@ static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now) "X_recv=%llu\n", old_x >> 6, hctx->ccid3hctx_x >> 6, hctx->ccid3hctx_x_calc, hctx->ccid3hctx_x_recv >> 6); - ccid3_update_send_time(hctx); + ccid3_update_send_interval(hctx); } } @@ -161,14 +153,12 @@ static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now) */ static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) { - 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. - */ + const u16 old_s = hctx->ccid3hctx_s; + + hctx->ccid3hctx_s = old_s == 0 ? len : (9 * old_s + len) / 10; + + if (hctx->ccid3hctx_s != old_s) + ccid3_update_send_interval(hctx); } /* @@ -228,7 +218,7 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data) /* The value of R is still undefined and so we can not recompute * the timout value. Keep initial value as per [RFC 4342, 5]. */ t_nfb = TFRC_INITIAL_TIMEOUT; - ccid3_update_send_time(hctx); + ccid3_update_send_interval(hctx); break; case TFRC_SSTATE_FBACK: /* @@ -334,8 +324,7 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); /* Set initial sending rate X/s to 1pps (X is scaled by 2^6) */ - ccid3_hc_tx_update_s(hctx, skb->len); - hctx->ccid3hctx_x = hctx->ccid3hctx_s; + hctx->ccid3hctx_x = hctx->ccid3hctx_s = skb->len; hctx->ccid3hctx_x <<= 6; /* First timeout, according to [RFC 3448, 4.2], is 1 second */ @@ -484,7 +473,7 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) hctx->ccid3hctx_x = scaled_div(w_init << 6, r_sample); hctx->ccid3hctx_t_ld = now; - ccid3_update_send_time(hctx); + ccid3_update_send_interval(hctx); ccid3_pr_debug("%s(%p), s=%u, MSS=%u, w_init=%u, " "R_sample=%dus, X=%u\n", dccp_role(sk), |