[DCCP] loss_interval: Move ccid3_hc_rx_update_li to loss_interval
Renaming it to dccp_li_update_li.
Also based on previous work by Ian McDonald.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 52a71a9..9d2e2c1 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -819,167 +819,6 @@
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 @@
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;