sctp: avoid refreshing heartbeat timer too often

[cascardo/linux.git] / net / sctp / transport.c

diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 9b6b48c..81b8667 100644 (file)
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -183,7 +183,7 @@ static void sctp_transport_destroy(struct sctp_transport *transport)
 /* Start T3_rtx timer if it is not already running and update the heartbeat
  * timer.  This routine is called every time a DATA chunk is sent.
  */
-void sctp_transport_reset_timers(struct sctp_transport *transport)
+void sctp_transport_reset_t3_rtx(struct sctp_transport *transport)
 {
        /* RFC 2960 6.3.2 Retransmission Timer Rules
         *
@@ -197,11 +197,18 @@ void sctp_transport_reset_timers(struct sctp_transport *transport)
                if (!mod_timer(&transport->T3_rtx_timer,
                               jiffies + transport->rto))
                        sctp_transport_hold(transport);
+}
+
+void sctp_transport_reset_hb_timer(struct sctp_transport *transport)
+{
+       unsigned long expires;
 
        /* When a data chunk is sent, reset the heartbeat interval.  */
-       if (!mod_timer(&transport->hb_timer,
-                      sctp_transport_timeout(transport)))
-           sctp_transport_hold(transport);
+       expires = jiffies + sctp_transport_timeout(transport);
+       if (time_before(transport->hb_timer.expires, expires) &&
+           !mod_timer(&transport->hb_timer,
+                      expires + prandom_u32_max(transport->rto)))
+               sctp_transport_hold(transport);
 }
 
 /* This transport has been assigned to an association.
@@ -595,13 +602,13 @@ void sctp_transport_burst_reset(struct sctp_transport *t)
 unsigned long sctp_transport_timeout(struct sctp_transport *trans)
 {
        /* RTO + timer slack +/- 50% of RTO */
-       unsigned long timeout = (trans->rto >> 1) + prandom_u32_max(trans->rto);
+       unsigned long timeout = trans->rto >> 1;
 
        if (trans->state != SCTP_UNCONFIRMED &&
            trans->state != SCTP_PF)
                timeout += trans->hbinterval;
 
-       return timeout + jiffies;
+       return timeout;
 }
 
 /* Reset transport variables to their initial values */