sctp: avoid refreshing heartbeat timer too often

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

diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 7fe56d0..41b081a 100644 (file)
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -69,8 +69,6 @@ static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
                             sctp_cmd_seq_t *commands,
                             gfp_t gfp);
 
-static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
-                                    struct sctp_transport *t);
 /********************************************************************
  * Helper functions
  ********************************************************************/
@@ -367,6 +365,7 @@ void sctp_generate_heartbeat_event(unsigned long data)
        struct sctp_association *asoc = transport->asoc;
        struct sock *sk = asoc->base.sk;
        struct net *net = sock_net(sk);
+       u32 elapsed, timeout;
 
        bh_lock_sock(sk);
        if (sock_owned_by_user(sk)) {
@@ -378,6 +377,16 @@ void sctp_generate_heartbeat_event(unsigned long data)
                goto out_unlock;
        }
 
+       /* Check if we should still send the heartbeat or reschedule */
+       elapsed = jiffies - transport->last_time_sent;
+       timeout = sctp_transport_timeout(transport);
+       if (elapsed < timeout) {
+               elapsed = timeout - elapsed;
+               if (!mod_timer(&transport->hb_timer, jiffies + elapsed))
+                       sctp_transport_hold(transport);
+               goto out_unlock;
+       }
+
        error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
                           SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
                           asoc->state, asoc->ep, asoc,
@@ -507,7 +516,7 @@ static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands,
                                             0);
 
                /* Update the hb timer to resend a heartbeat every rto */
-               sctp_cmd_hb_timer_update(commands, transport);
+               sctp_transport_reset_hb_timer(transport);
        }
 
        if (transport->state != SCTP_INACTIVE &&
@@ -634,11 +643,8 @@ static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
         * hold a reference on the transport to make sure none of
         * the needed data structures go away.
         */
-       list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
-
-               if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
-                       sctp_transport_hold(t);
-       }
+       list_for_each_entry(t, &asoc->peer.transport_addr_list, transports)
+               sctp_transport_reset_hb_timer(t);
 }
 
 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
@@ -669,15 +675,6 @@ static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
 }
 
 
-/* Helper function to update the heartbeat timer. */
-static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
-                                    struct sctp_transport *t)
-{
-       /* Update the heartbeat timer.  */
-       if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
-               sctp_transport_hold(t);
-}
-
 /* Helper function to handle the reception of an HEARTBEAT ACK.  */
 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
                                  struct sctp_association *asoc,
@@ -742,8 +739,7 @@ static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
        sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
 
        /* Update the heartbeat timer.  */
-       if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
-               sctp_transport_hold(t);
+       sctp_transport_reset_hb_timer(t);
 
        if (was_unconfirmed && asoc->peer.transport_count == 1)
                sctp_transport_immediate_rtx(t);
@@ -1614,7 +1610,7 @@ static int sctp_cmd_interpreter(sctp_event_t event_type,
 
                case SCTP_CMD_HB_TIMER_UPDATE:
                        t = cmd->obj.transport;
-                       sctp_cmd_hb_timer_update(commands, t);
+                       sctp_transport_reset_hb_timer(t);
                        break;
 
                case SCTP_CMD_HB_TIMERS_STOP: