From 0abf6796c3d8ae8f5ea8624668424bc1554de25e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timo=20Ter=C3=A4s?= Date: Fri, 15 Jan 2016 17:36:29 +0200 Subject: zebra: atomic FIB updates MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit updates the kernel API so that route changes are atomically updated using change/replaces messages instead of first sending a withdraw followed with update. Same for zclient updates, changes are sent as single ADD instead of DELETE + ADD. Signed-off-by: Timo Teräs --- zebra/rt_netlink.c | 40 ++++++++++++++++++---------------------- 1 file changed, 18 insertions(+), 22 deletions(-) (limited to 'zebra/rt_netlink.c') diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c index 614f8099..4625ceab 100644 --- a/zebra/rt_netlink.c +++ b/zebra/rt_netlink.c @@ -1607,8 +1607,7 @@ _netlink_route_debug( /* Routing table change via netlink interface. */ static int -netlink_route_multipath (int cmd, struct prefix *p, struct rib *rib, - int family) +netlink_route_multipath (int cmd, struct prefix *p, struct rib *rib) { int bytelen; struct sockaddr_nl snl; @@ -1616,6 +1615,7 @@ netlink_route_multipath (int cmd, struct prefix *p, struct rib *rib, int recursing; int nexthop_num; int discard; + int family = PREFIX_FAMILY(p); const char *routedesc; struct @@ -1632,7 +1632,7 @@ netlink_route_multipath (int cmd, struct prefix *p, struct rib *rib, bytelen = (family == AF_INET ? 4 : 16); req.n.nlmsg_len = NLMSG_LENGTH (sizeof (struct rtmsg)); - req.n.nlmsg_flags = NLM_F_CREATE | NLM_F_REQUEST; + req.n.nlmsg_flags = NLM_F_CREATE | NLM_F_REPLACE | NLM_F_REQUEST; req.n.nlmsg_type = cmd; req.r.rtm_family = family; req.r.rtm_table = rib->table; @@ -1803,30 +1803,26 @@ skip: } int -kernel_add_ipv4 (struct prefix *p, struct rib *rib) +kernel_route_rib (struct prefix *p, struct rib *old, struct rib *new) { - return netlink_route_multipath (RTM_NEWROUTE, p, rib, AF_INET); -} + int ret; -int -kernel_delete_ipv4 (struct prefix *p, struct rib *rib) -{ - return netlink_route_multipath (RTM_DELROUTE, p, rib, AF_INET); -} + if (!old && new) + return netlink_route_multipath (RTM_NEWROUTE, p, new); + if (old && !new) + return netlink_route_multipath (RTM_DELROUTE, p, old); -#ifdef HAVE_IPV6 -int -kernel_add_ipv6 (struct prefix *p, struct rib *rib) -{ - return netlink_route_multipath (RTM_NEWROUTE, p, rib, AF_INET6); -} + /* Replace, can be done atomically if metric does not change; + * netlink uses [prefix, tos, priority] to identify prefix */ + if (old->metric == new->metric) + return netlink_route_multipath (RTM_NEWROUTE, p, new); -int -kernel_delete_ipv6 (struct prefix *p, struct rib *rib) -{ - return netlink_route_multipath (RTM_DELROUTE, p, rib, AF_INET6); + /* Add + delete so the prefix does not disappear temporarily */ + ret = netlink_route_multipath (RTM_NEWROUTE, p, new); + if (netlink_route_multipath (RTM_DELROUTE, p, old) < 0) + ret = -1; + return ret; } -#endif /* HAVE_IPV6 */ /* Interface address modification. */ static int -- cgit v1.2.3