diff options
Diffstat (limited to 'bgpd/bgp_session.h')
| -rw-r--r-- | bgpd/bgp_session.h | 40 |
1 files changed, 17 insertions, 23 deletions
diff --git a/bgpd/bgp_session.h b/bgpd/bgp_session.h index 967286ef..af376f9a 100644 --- a/bgpd/bgp_session.h +++ b/bgpd/bgp_session.h @@ -40,7 +40,6 @@ #define Inline static inline #endif - /*============================================================================== * BGP Session data structure. * @@ -57,14 +56,16 @@ * NB: the session structure is shared by the Routeing Engine and the BGP * Engine, so there is a mutex to coordinate access. * - * The information in this shared structure is only required every now and - * then, so the overhead of a mutex operation for every access is not an - * issue. + * For simplicity, the BGP Engine may lock the session associated with the + * connection it is dealing with. + * + * Parts of the session structure are private to the Peering Engine, and + * do not require the mutex for access. * * NB: the connections associated with a BGP session are private to the BGP - * Engine when sessions are disabled or have failed, there will be no - * connections. + * Engine. * + * When sessions are disabled or have failed, there will be no connections. */ /* Statistics */ @@ -87,10 +88,13 @@ struct bgp_session_stats struct bgp_session { + /* The following are set when the session is created, and not changed + * thereafter. + */ bgp_peer peer ; /* peer whose session this is */ - bgp_peer_index_entry index_entry ; /* and its index entry */ + /* This is a *recursive* mutex */ qpt_mutex_t mutex ; /* for access to the rest */ /* While sIdle and sStopped: @@ -111,27 +115,18 @@ struct bgp_session * assumes that a session will not be destroyed while it is sEnabled, * sEstablished or sStopping. * - * Only the Peering Engine touches the state and defer_enable items. - * - * The made flag is cleared by the Peering Engine before enabling a session, - * and is set by the BGP Engine when the session becomes sEstablished. - * - * The Peering Engine may use this flag in sStopped state to see if the - * session was ever established. + * These are private to the Peering Engine. */ bgp_session_state_t state ; int defer_enable ; /* set when waiting for stop */ - flag_t made ; /* set when -> sEstablished */ - /* Flow control. Incremented when an update packet is sent * from peering to BGP engine. Decremented when packet processed * by BGP engine. On transition to 0 BGP engine should send an XON. */ - int flow_control; - /* These belong to the Peering Engine, and may be set when a session + /* These are private to the Peering Engine, and are set each time a session * event message is received from the BGP Engine. */ bgp_session_event_t event ; /* last event */ @@ -163,6 +158,10 @@ struct bgp_session int ttl ; /* TTL to set, if not zero */ unsigned short port ; /* destination port for peer */ + /* TODO: ifindex and ifaddress should be rebound if the peer hears any + * bgp_session_eTCP_failed or bgp_session_eTCP_error -- in case interface + * state has changed, for the better. + */ char* ifname ; /* interface to bind to, if any */ unsigned ifindex ; /* and its index, if any */ union sockunion* ifaddress ; /* address to bind to, if any */ @@ -220,7 +219,6 @@ struct bgp_session flag_t active ; } ; - /*============================================================================== * Mqueue messages related to sessions * @@ -292,8 +290,6 @@ struct bgp_session_ttl_args /* to bgp Engine */ } ; MQB_ARGS_SIZE_OK(bgp_session_ttl_args) ; - - /*============================================================================== * Session mutex lock/unlock */ @@ -361,8 +357,6 @@ bgp_session_get_stats(bgp_session session, struct bgp_session_stats *stats); /*============================================================================== * Session data access functions. - * - * */ extern int |