diff options
Diffstat (limited to 'nest')
-rw-r--r-- | nest/rt-table.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/nest/rt-table.c b/nest/rt-table.c index 0224d434..194eadf8 100644 --- a/nest/rt-table.c +++ b/nest/rt-table.c @@ -564,34 +564,47 @@ rt_notify_basic(struct channel *c, net *net, rte *new0, rte *old0, int refeed) * and the end of refeed - if a newly filtered route disappears during this * period, proper withdraw is not sent (because old would be also filtered) * and the route is not refeeded (because it disappeared before that). - * Therefore, we also do not try to run the filter on old routes that are - * older than the last filter change. + * This is handled below as a special case. */ if (new) new = export_filter(c, new, &new_free, 0); - if (old && !(refeed || ((old->lastmod <= c->last_tx_filter_change) && - (p != old->sender->proto)))) + if (old && !refeed) old = export_filter(c, old, &old_free, 1); if (!new && !old) { /* * As mentioned above, 'old' value may be incorrect in some race conditions. - * We generally ignore it with the exception of withdraw to pipe protocol. - * In that case we rather propagate unfiltered withdraws regardless of - * export filters to ensure that when a protocol is flushed, its routes are - * removed from all tables. Possible spurious unfiltered withdraws are not - * problem here as they are ignored if there is no corresponding route at - * the other end of the pipe. We directly call rt_notify() hook instead of + * We generally ignore it with two exceptions: + * + * First, withdraw to pipe protocol. In that case we rather propagate + * unfiltered withdraws regardless of export filters to ensure that when a + * protocol is flushed, its routes are removed from all tables. Possible + * spurious unfiltered withdraws are not problem here as they are ignored if + * there is no corresponding route at the other end of the pipe. + * + * Second, recent filter change. If old route is older than filter change, + * then it was previously evaluated by a different filter and we do not know + * whether it was really propagated. In that case we rather send spurious + * withdraw than do nothing and possibly cause phantom routes. + * + * In both cases wqe directly call rt_notify() hook instead of * do_rt_notify() to avoid logging and stat counters. */ + int pipe_withdraw = 0, filter_change = 0; #ifdef CONFIG_PIPE - if ((p->proto == &proto_pipe) && !new0 && (p != old0->sender->proto)) - p->rt_notify(p, c, net, NULL, old0); + pipe_withdraw = (p->proto == &proto_pipe) && !new0; #endif + filter_change = old0 && (old0->lastmod <= c->last_tx_filter_change); + + if ((pipe_withdraw || filter_change) && (p != old0->sender->proto)) + { + c->stats.exp_withdraws_accepted++; + p->rt_notify(p, c, net, NULL, old0); + } return; } |