diff options
Diffstat (limited to 'bgpd/bgp_session.c')
| -rw-r--r-- | bgpd/bgp_session.c | 55 |
1 files changed, 29 insertions, 26 deletions
diff --git a/bgpd/bgp_session.c b/bgpd/bgp_session.c index 25615f99..fdba5fd7 100644 --- a/bgpd/bgp_session.c +++ b/bgpd/bgp_session.c @@ -41,10 +41,7 @@ bgp_session_defer_if_stopping(bgp_session session); * A session is shared by the Routeing Engine and the BGP Engine -- so there * is a mutex to coordinate access. * - * NB: to avoid deadlock, do NOT attempt to lookup a peer or session while - * a session mutex ! - * - * A session is created when the bgp peer is first enabled, and may be destroyed + * A session is created some time before it is enabled, and may be destroyed * when the peer is disabled, or once the session has stopped. * * A session may be in one of four states: @@ -52,21 +49,22 @@ bgp_session_defer_if_stopping(bgp_session session); * * bgp_session_Idle -- not doing anything * * bgp_session_Enabled -- the BGP Engine is trying to connect * * bgp_session_Established -- the BGP Engine is exchanging updates etc + * * bgp_session_Stopping -- the BGP Engine is stopping the session * * bgp_session_Stopped -- a session has come to a dead stop * * NB: in Idle and Stopped states the BGP Engine has no interest in the session. * These are known as the "inactive" states. * - * NB: in Enabled and Established states the Routeing Engine it may be too late - * to change items in the session ! These are known as the "active" states. + * NB: in Enabled, Established and Stopping states the BGP Engine is running + * connection(s) for the session. These are known as the "active" states. * - * NB: once a session is enabled the BGP_Engine looks after the state, up to - * and including setting the Stopped state. + * While the session is active the Routeing Engine should not attempt to + * change any shared item in the session, except under the mutex. And + * even then it may make no sense ! * * The BGP Engine's primary interest is in its (private) bgp_connection - * structure(s), which (while a session is Enabled or Established) are pointed - * to by their associated session. - * + * structure(s), which (while a session is Enabled, Established or Stopping) + * are pointed to by their associated session. */ /*============================================================================== @@ -313,15 +311,19 @@ bgp_session_disable(bgp_peer peer, bgp_notify notification) session = peer->session ; assert((session != NULL) && (session->peer == peer)) ; - /* Should do nothing if session is not active. */ + /* Do nothing if session is not active, or is already stopping. */ - if (!bgp_session_is_active(session)) + if ( (session->state != bgp_session_sEnabled) && + (session->state != bgp_session_sEstablished) ) ; { bgp_notify_free(¬ification) ; /* discard any bgp_notify */ return ; } ; - /* Now ask the BGP engine to disable the session. + /* Now change to stopping state */ + session->state = bgp_session_sStopping; + + /* Ask the BGP engine to disable the session. * * NB: it is, of course, possible that the session will stop between * issuing the disable and it being processed by the BGP Engine. @@ -354,10 +356,8 @@ bgp_session_do_disable(mqueue_block mqb, mqb_flag_t flag) bgp_session session = mqb_get_arg0(mqb) ; struct bgp_session_disable_args* args = mqb_get_args(mqb) ; - session->state = bgp_session_sStopping; /* TODO: disable session */ - - bgp_notify_free(&args->notification) ; /* discard any bgp_notify */ + bgp_fsm_disable_session(session, args->notification) ; } ; mqb_free(mqb) ; @@ -365,12 +365,13 @@ bgp_session_do_disable(mqueue_block mqb, mqb_flag_t flag) /*============================================================================== * Send session event signal from BGP Engine to Routeing Engine - * - * The event has been posted to the session, and now is dispatched to the - * Routeing Engine. */ extern void -bgp_session_event(bgp_session session) +bgp_session_event(bgp_session session, bgp_session_event_t event, + bgp_notify notification, + int err, + bgp_connection_ord_t ordinal, + int stopped) { struct bgp_session_event_args* args ; mqueue_block mqb ; @@ -379,10 +380,11 @@ bgp_session_event(bgp_session session) args = mqb_get_args(mqb) ; - args->event = session->event ; - args->notification = bgp_notify_dup(session->notification) ; - args->state = session->state ; - args->ordinal = session->ordinal ; + args->event = event ; + args->notification = bgp_notify_dup(notification) ; + args->err = err ; + args->ordinal = ordinal ; + args->stopped = stopped, bgp_to_peering_engine(mqb) ; } @@ -468,7 +470,8 @@ bgp_session_is_active(bgp_session session) else { active = ( (session->state == bgp_session_sEnabled) - || (session->state == bgp_session_sEstablished) ) ; + || (session->state == bgp_session_sEstablished) + || (session->state == bgp_session_sStopping) ) ; if (!active) assert(session->index_entry->accept == NULL) ; |