diff options
Diffstat (limited to 'net/dccp/ccids/ccid3.c')
| -rw-r--r-- | net/dccp/ccids/ccid3.c | 179 |
1 files changed, 9 insertions, 170 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index 52a71a900eb..9d2e2c193cc 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -819,167 +819,6 @@ static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) return 0; } -/* calculate first loss interval - * - * returns estimated loss interval in usecs */ - -static u32 ccid3_hc_rx_calc_first_li(struct sock *sk, - struct list_head *hist_list, - struct timeval *last_feedback, - u16 s, u32 bytes_recv, - u32 previous_x_recv) -{ - struct dccp_rx_hist_entry *entry, *next, *tail = NULL; - u32 x_recv, p; - suseconds_t rtt, delta; - struct timeval tstamp = { 0, 0 }; - int interval = 0; - int win_count = 0; - int step = 0; - u64 fval; - - list_for_each_entry_safe(entry, next, hist_list, dccphrx_node) { - if (dccp_rx_hist_entry_data_packet(entry)) { - tail = entry; - - switch (step) { - case 0: - tstamp = entry->dccphrx_tstamp; - win_count = entry->dccphrx_ccval; - step = 1; - break; - case 1: - interval = win_count - entry->dccphrx_ccval; - if (interval < 0) - interval += TFRC_WIN_COUNT_LIMIT; - if (interval > 4) - goto found; - break; - } - } - } - - if (unlikely(step == 0)) { - DCCP_WARN("%s(%p), packet history has no data packets!\n", - dccp_role(sk), sk); - return ~0; - } - - if (unlikely(interval == 0)) { - DCCP_WARN("%s(%p), Could not find a win_count interval > 0." - "Defaulting to 1\n", dccp_role(sk), sk); - interval = 1; - } -found: - if (!tail) { - DCCP_CRIT("tail is null\n"); - return ~0; - } - - delta = timeval_delta(&tstamp, &tail->dccphrx_tstamp); - DCCP_BUG_ON(delta < 0); - - rtt = delta * 4 / interval; - ccid3_pr_debug("%s(%p), approximated RTT to %dus\n", - dccp_role(sk), sk, (int)rtt); - - /* - * Determine the length of the first loss interval via inverse lookup. - * Assume that X_recv can be computed by the throughput equation - * s - * X_recv = -------- - * R * fval - * Find some p such that f(p) = fval; return 1/p [RFC 3448, 6.3.1]. - */ - if (rtt == 0) { /* would result in divide-by-zero */ - DCCP_WARN("RTT==0\n"); - return ~0; - } - - dccp_timestamp(sk, &tstamp); - delta = timeval_delta(&tstamp, last_feedback); - DCCP_BUG_ON(delta <= 0); - - x_recv = scaled_div32(bytes_recv, delta); - if (x_recv == 0) { /* would also trigger divide-by-zero */ - DCCP_WARN("X_recv==0\n"); - if (previous_x_recv == 0) { - DCCP_BUG("stored value of X_recv is zero"); - return ~0; - } - x_recv = previous_x_recv; - } - - fval = scaled_div(s, rtt); - fval = scaled_div32(fval, x_recv); - p = tfrc_calc_x_reverse_lookup(fval); - - ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " - "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); - - if (p == 0) - return ~0; - else - return 1000000 / p; -} - -static void ccid3_hc_rx_update_li(struct sock *sk, - struct dccp_li_hist *li_hist, - struct list_head *li_hist_list, - struct list_head *hist_list, - struct timeval *last_feedback, - u16 s, u32 bytes_recv, - u32 previous_x_recv, - u64 seq_loss, u8 win_loss) -{ - struct dccp_li_hist_entry *head; - u64 seq_temp; - - if (list_empty(li_hist_list)) { - if (!dccp_li_hist_interval_new(li_hist, li_hist_list, - seq_loss, win_loss)) - return; - - head = list_entry(li_hist_list->next, struct dccp_li_hist_entry, - dccplih_node); - head->dccplih_interval = - ccid3_hc_rx_calc_first_li(sk, hist_list, - last_feedback, s, - bytes_recv, - previous_x_recv); - } else { - struct dccp_li_hist_entry *entry; - struct list_head *tail; - - head = list_entry(li_hist_list->next, struct dccp_li_hist_entry, - dccplih_node); - /* FIXME win count check removed as was wrong */ - /* should make this check with receive history */ - /* and compare there as per section 10.2 of RFC4342 */ - - /* new loss event detected */ - /* calculate last interval length */ - seq_temp = dccp_delta_seqno(head->dccplih_seqno, seq_loss); - entry = dccp_li_hist_entry_new(li_hist, GFP_ATOMIC); - - if (entry == NULL) { - DCCP_BUG("out of memory - can not allocate entry"); - return; - } - - list_add(&entry->dccplih_node, li_hist_list); - - tail = li_hist_list->prev; - list_del(tail); - kmem_cache_free(li_hist->dccplih_slab, tail); - - /* Create the newest interval */ - entry->dccplih_seqno = seq_loss; - entry->dccplih_interval = seq_temp; - entry->dccplih_win_count = win_loss; - } -} - static int ccid3_hc_rx_detect_loss(struct sock *sk, struct dccp_rx_hist_entry *packet) { @@ -1005,15 +844,15 @@ static int ccid3_hc_rx_detect_loss(struct sock *sk, while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno) > TFRC_RECV_NUM_LATE_LOSS) { loss = 1; - ccid3_hc_rx_update_li(sk, ccid3_li_hist, - &hcrx->ccid3hcrx_li_hist, - &hcrx->ccid3hcrx_hist, - &hcrx->ccid3hcrx_tstamp_last_feedback, - hcrx->ccid3hcrx_s, - hcrx->ccid3hcrx_bytes_recv, - hcrx->ccid3hcrx_x_recv, - hcrx->ccid3hcrx_seqno_nonloss, - hcrx->ccid3hcrx_ccval_nonloss); + dccp_li_update_li(sk, ccid3_li_hist, + &hcrx->ccid3hcrx_li_hist, + &hcrx->ccid3hcrx_hist, + &hcrx->ccid3hcrx_tstamp_last_feedback, + hcrx->ccid3hcrx_s, + hcrx->ccid3hcrx_bytes_recv, + hcrx->ccid3hcrx_x_recv, + hcrx->ccid3hcrx_seqno_nonloss, + hcrx->ccid3hcrx_ccval_nonloss); tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss; dccp_inc_seqno(&tmp_seqno); hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno; 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