pimd: RPF change after winner election

Problem:
   Once Assert election is over and winner is elected, the downstream router has to prune from the upstream LOSER if it has joined already and have to join with upstream elected WINNER

pim_rpf_update function takes care of changing the rpf_ch if the
existing one is PIM_IFASSERT_I_AM_LOSER

Signed-off-by: plsaranya <Saranya_Panjarathina@dell.com>

diff --git a/pimd/pim_assert.c b/pimd/pim_assert.c
index e7fff4db6f6c59888b4b78de02616492ceb05969..6bd8321f076fca3a0e64337623af2e0b7be88c22 100644 (file)
--- a/pimd/pim_assert.c
+++ b/pimd/pim_assert.c
@@ -34,6 +34,7 @@
 #include "pim_hello.h"
 #include "pim_macro.h"
 #include "pim_assert.h"
+#include "pim_zebra.h"
 #include "pim_ifchannel.h"
 
 static int assert_action_a3(struct pim_ifchannel *ch);
@@ -50,6 +51,8 @@ void pim_ifassert_winner_set(struct pim_ifchannel *ch,
        int winner_changed = !!pim_addr_cmp(ch->ifassert_winner, winner);
        int metric_changed = !pim_assert_metric_match(
                &ch->ifassert_winner_metric, &winner_metric);
+       enum pim_rpf_result rpf_result;
+       struct pim_rpf old_rpf;
 
        if (PIM_DEBUG_PIM_EVENTS) {
                if (ch->ifassert_state != new_state) {
@@ -74,6 +77,22 @@ void pim_ifassert_winner_set(struct pim_ifchannel *ch,
        ch->ifassert_creation = pim_time_monotonic_sec();
 
        if (winner_changed || metric_changed) {
+               if (winner_changed) {
+                       old_rpf.source_nexthop.interface =
+                               ch->upstream->rpf.source_nexthop.interface;
+                       rpf_result = pim_rpf_update(pim_ifp->pim, ch->upstream,
+                                                   &old_rpf, __func__);
+                       if (rpf_result == PIM_RPF_CHANGED ||
+                           (rpf_result == PIM_RPF_FAILURE &&
+                            old_rpf.source_nexthop.interface))
+                               pim_zebra_upstream_rpf_changed(
+                                       pim_ifp->pim, ch->upstream, &old_rpf);
+                       /* update kernel multicast forwarding cache (MFC) */
+                       if (ch->upstream->rpf.source_nexthop.interface &&
+                           ch->upstream->channel_oil)
+                               pim_upstream_mroute_iif_update(
+                                       ch->upstream->channel_oil, __func__);
+               }
                pim_upstream_update_join_desired(pim_ifp->pim, ch->upstream);
                pim_ifchannel_update_could_assert(ch);
                pim_ifchannel_update_assert_tracking_desired(ch);