diff options
Diffstat (limited to 'bgpd/bgp_route.c')
| -rw-r--r-- | bgpd/bgp_route.c | 47 |
1 files changed, 35 insertions, 12 deletions
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c index 2ce2ef4d..5dde41de 100644 --- a/bgpd/bgp_route.c +++ b/bgpd/bgp_route.c @@ -2527,11 +2527,10 @@ bgp_clear_node_complete (struct work_queue *wq) { struct peer *peer = wq->spec.data; - UNSET_FLAG (peer->sflags, PEER_STATUS_CLEARING); peer_unlock (peer); /* bgp_clear_node_complete */ /* Tickle FSM to start moving again */ - BGP_EVENT_ADD (peer, BGP_Start); + BGP_EVENT_ADD (peer, Clearing_Completed); } static void @@ -2593,9 +2592,10 @@ bgp_clear_route (struct peer *peer, afi_t afi, safi_t safi) if (peer->clear_node_queue == NULL) bgp_clear_node_queue_init (peer); - /* bgp_fsm.c will not bring CLEARING sessions out of Idle this - * protects against peers which flap faster than we can we clear, - * which could lead to: + /* bgp_fsm.c keeps sessions in state Clearing, not transitioning to + * Idle until it receives a Clearing_Completed event. This protects + * against peers which flap faster than we can we clear, which could + * lead to: * * a) race with routes from the new session being installed before * clear_route_node visits the node (to delete the route of that @@ -2604,11 +2604,8 @@ bgp_clear_route (struct peer *peer, afi_t afi, safi_t safi) * on the process_main queue. Fast-flapping could cause that queue * to grow and grow. */ - if (!CHECK_FLAG (peer->sflags, PEER_STATUS_CLEARING)) - { - SET_FLAG (peer->sflags, PEER_STATUS_CLEARING); - peer_lock (peer); /* bgp_clear_node_complete */ - } + if (!peer->clear_node_queue->thread) + peer_lock (peer); /* bgp_clear_node_complete */ if (safi != SAFI_MPLS_VPN) bgp_clear_route_table (peer, afi, safi, NULL, NULL); @@ -2624,11 +2621,37 @@ bgp_clear_route (struct peer *peer, afi_t afi, safi_t safi) bgp_clear_route_table (peer, afi, safi, NULL, rsclient); } - /* If no routes were cleared, nothing was added to workqueue, run the - * completion function now. + /* If no routes were cleared, nothing was added to workqueue, the + * completion function won't be run by workqueue code - call it here. + * + * Additionally, there is a presumption in FSM that clearing is only + * needed if peer state is Established - peers in pre-Established states + * shouldn't have any route-update state associated with them (in or out). + * + * We still get here from FSM through bgp_stop->clear_route_all in + * pre-Established though, so this is a useful sanity check to ensure + * the assumption above holds. + * + * At some future point, this check could be move to the top of the + * function, and do a quick early-return when state is + * pre-Established, avoiding above list and table scans. Once we're + * sure it is safe.. */ if (!peer->clear_node_queue->thread) bgp_clear_node_complete (peer->clear_node_queue); + else + { + /* clearing queue scheduled. Normal if in Established state + * (and about to transition out of it), but otherwise... + */ + if (peer->status != Established) + { + plog_err (peer->log, "%s [Error] State %s is not Established," + " but routes were cleared - bug!", + peer->host, LOOKUP (bgp_status_msg, peer->status)); + assert (peer->status == Established); + } + } } void |