1 files changed, 16 insertions, 14 deletions

diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c
index 5b3ce0688c5c..b1ae8f8259e5 100644
--- a/net/dccp/ccids/lib/loss_interval.c
+++ b/net/dccp/ccids/lib/loss_interval.c
@@ -86,21 +86,26 @@ static void tfrc_lh_calc_i_mean(struct tfrc_loss_hist *lh)
 
 /**
  * tfrc_lh_update_i_mean  -  Update the `open' loss interval I_0
- * For recomputing p: returns `true' if p > p_prev  <=>  1/p < 1/p_prev
+ * This updates I_mean as the sequence numbers increase. As a consequence, the
+ * open loss interval I_0 increases, hence p = W_tot/max(I_tot0, I_tot1)
+ * decreases, and thus there is no need to send renewed feedback.
  */
-u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb)
+void tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb)
 {
         struct tfrc_loss_interval *cur = tfrc_lh_peek(lh);
-        u32 old_i_mean = lh->i_mean;
         s64 len;
 
         if (cur == NULL)                        /* not initialised */
-                return 0;
+                return;
+
+        /* FIXME: should probably also count non-data packets (RFC 4342, 6.1) */
+        if (!dccp_data_packet(skb))
+                return;
 
         len = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq) + 1;
 
         if (len - (s64)cur->li_length <= 0)     /* duplicate or reordered */
-                return 0;
+                return;
 
         if (SUB16(dccp_hdr(skb)->dccph_ccval, cur->li_ccval) > 4)
                 /*
@@ -114,14 +119,11 @@ u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb)
                 cur->li_is_closed = 1;
 
         if (tfrc_lh_length(lh) == 1)            /* due to RFC 3448, 6.3.1 */
-                return 0;
+                return;
 
         cur->li_length = len;
         tfrc_lh_calc_i_mean(lh);
-
-        return (lh->i_mean < old_i_mean);
 }
-EXPORT_SYMBOL_GPL(tfrc_lh_update_i_mean);
 
 /* Determine if `new_loss' does begin a new loss interval [RFC 4342, 10.2] */
 static inline u8 tfrc_lh_is_new_loss(struct tfrc_loss_interval *cur,
@@ -138,18 +140,18 @@ static inline u8 tfrc_lh_is_new_loss(struct tfrc_loss_interval *cur,
  * @sk:            Used by @calc_first_li in caller-specific way (subtyping)
  * Updates I_mean and returns 1 if a new interval has in fact been added to @lh.
  */
-int tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh,
-                         u32 (*calc_first_li)(struct sock *), struct sock *sk)
+bool tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh,
+                          u32 (*calc_first_li)(struct sock *), struct sock *sk)
 {
         struct tfrc_loss_interval *cur = tfrc_lh_peek(lh), *new;
 
         if (cur != NULL && !tfrc_lh_is_new_loss(cur, tfrc_rx_hist_loss_prev(rh)))
-                return 0;
+                return false;
 
         new = tfrc_lh_demand_next(lh);
         if (unlikely(new == NULL)) {
                 DCCP_CRIT("Cannot allocate/add loss record.");
-                return 0;
+                return false;
         }
 
         new->li_seqno     = tfrc_rx_hist_loss_prev(rh)->tfrchrx_seqno;
@@ -167,7 +169,7 @@ int tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh,
 
                 tfrc_lh_calc_i_mean(lh);
         }
-        return 1;
+        return true;
 }
 EXPORT_SYMBOL_GPL(tfrc_lh_interval_add);