batman-adv: mcast: shorten multicast tt/tvlv worker spinlock section

It is not necessary to hold the mla_lock spinlock during the whole
multicast tt/tvlv worker callback. Just holding it during the checks and
updates of the bat_priv stored multicast flags and mla_list is enough.

Therefore this patch splits batadv_mcast_mla_tvlv_update() in two:
batadv_mcast_mla_flags_get() at the beginning of the worker to gather
and calculate the new multicast flags, which does not need any locking
as it neither reads from nor writes to bat_priv->mcast.

And batadv_mcast_mla_flags_update() at the end of the worker which
commits the newly calculated flags and lists to bat_priv->mcast and
therefore needs the lock.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

1 files changed, 0 insertions, 5 deletions

diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 499afbce44dc..c7a2e77ca1da 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -804,11 +804,6 @@ static int batadv_softif_init_late(struct net_device *dev)
 	atomic_set(&bat_priv->distributed_arp_table, 1);
 #endif
 #ifdef CONFIG_BATMAN_ADV_MCAST
-	bat_priv->mcast.querier_ipv4.exists = false;
-	bat_priv->mcast.querier_ipv4.shadowing = false;
-	bat_priv->mcast.querier_ipv6.exists = false;
-	bat_priv->mcast.querier_ipv6.shadowing = false;
-	bat_priv->mcast.flags = BATADV_NO_FLAGS;
 	atomic_set(&bat_priv->multicast_mode, 1);
 	atomic_set(&bat_priv->multicast_fanout, 16);
 	atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);