This patch adds an 'mcast' log level. Currently, it will print changes relevant to a nodes own multicast flag changes.
Signed-off-by: Linus Lüssing linus.luessing@web.de --- multicast.c | 138 ++++++++++++++++++++++++++++++++++++++++++++++++++++-- soft-interface.c | 5 ++ types.h | 17 +++++++ 3 files changed, 155 insertions(+), 5 deletions(-)
diff --git a/multicast.c b/multicast.c index c05f64a..915582d 100644 --- a/multicast.c +++ b/multicast.c @@ -292,6 +292,119 @@ static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv) }
/** + * batadv_mcast_querier_log - debug output regarding the querier status on link + * @bat_priv: the bat priv with all the soft interface information + * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD") + * @old_state: the previous querier state on our link + * @new_state: the new querier state on our link + * + * Outputs debug messages to the logging facility with log level 'mcast' + * regarding changes to the querier status on the link which are relevant + * to our multicast optimizations. + * + * Usually this is about whether a querier appeared or vanished in + * our mesh or whether the querier is in the suboptimal position of being + * behind our local bridge segment: Snooping switches will directly + * forward listener reports to the querier, therefore batman-adv and + * the bridge will potentially not see these listeners - the querier is + * potentially shadowing listeners from us then. + * + * This is only interesting for nodes with a bridge on top of their + * soft interface. + */ +static void +batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto, + struct batadv_mcast_querier_state *old_state, + struct batadv_mcast_querier_state *new_state) +{ + if (!old_state->exists && new_state->exists) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "%s Querier appeared\n", str_proto); + else if (old_state->exists && !new_state->exists) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "%s Querier disappeared\n", str_proto); + else if (!bat_priv->mcast.bridged && !new_state->exists) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "Note: No %s Querier present\n", str_proto); + + if (new_state->exists) { + if (!old_state->shadowing && new_state->shadowing) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "%s Querier is behind our bridged segment: Might shadow listeners\n", + str_proto); + else if (old_state->shadowing && !new_state->shadowing) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "%s Querier is not behind our bridged segment\n", + str_proto); + } +} + +/** + * batadv_mcast_bridge_log - debug output for topology changes in bridged setups + * @bat_priv: the bat priv with all the soft interface information + * @bridged: a flag about whether the soft interface is currently bridged or not + * @querier_ipv4: (maybe) new status of a potential, selected IGMP querier + * @querier_ipv6: (maybe) new status of a potential, selected MLD querier + * + * If no bridges are ever used on this node, then this function does nothing. + * + * Otherwise this function outputs debug information to the 'mcast' log level + * which might be relevant to our multicast optimizations. + * + * More precisely, it outputs information when a bridge interface is added or + * removed from a soft interface. And when a bridge is present, it further + * outputs information about the querier state which is relevant for the + * multicast flags this node is going to set. + */ +static void +batadv_mcast_bridge_log(struct batadv_priv *bat_priv, bool bridged, + struct batadv_mcast_querier_state *querier_ipv4, + struct batadv_mcast_querier_state *querier_ipv6) +{ + if (!bat_priv->mcast.bridged && bridged) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "Bridge added: Setting Unsnoopables(U)-flag\n"); + else if (bat_priv->mcast.bridged && !bridged) + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "Bridge removed: Unsetting Unsnoopables(U)-flag\n"); + + if (bridged) { + batadv_mcast_querier_log(bat_priv, "IGMP", + &bat_priv->mcast.querier_ipv4, + querier_ipv4); + batadv_mcast_querier_log(bat_priv, "MLD", + &bat_priv->mcast.querier_ipv6, + querier_ipv6); + } +} + +/** + * batadv_mcast_flags_logs - output debug information about mcast flag changes + * @bat_priv: the bat priv with all the soft interface information + * @mcast_flags: flags indicating the new multicast state + * + * Whenever the multicast flags this nodes announces changes (@mcast_flags vs. + * bat_priv->mcast.flags), this notifies userspace via the 'mcast' log level. + */ +static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, uint8_t flags) +{ + uint8_t old_flags = bat_priv->mcast.flags; + char str_old_flags[] = "[...]"; + + sprintf(str_old_flags, "[%c%c%c]", + old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES ? 'U' : '.', + old_flags & BATADV_MCAST_WANT_ALL_IPV4 ? '4' : '.', + old_flags & BATADV_MCAST_WANT_ALL_IPV6 ? '6' : '.'); + + batadv_dbg(BATADV_DBG_MCAST, bat_priv, + "Changing multicast flags from '%s' to '[%c%c%c]'\n", + bat_priv->mcast.enabled ? str_old_flags : "<undefined>", + flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES ? 'U' : '.', + flags & BATADV_MCAST_WANT_ALL_IPV4 ? '4' : '.', + flags & BATADV_MCAST_WANT_ALL_IPV6 ? '6' : '.'); +} + +/** * batadv_mcast_mla_tvlv_update - update multicast tvlv * @bat_priv: the bat priv with all the soft interface information * @@ -304,18 +417,28 @@ static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv) static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv) { struct batadv_tvlv_mcast_data mcast_data; + struct batadv_mcast_querier_state querier4 = {false, false}; + struct batadv_mcast_querier_state querier6 = {false, false}; struct net_device *dev = bat_priv->soft_iface; + bool bridged;
mcast_data.flags = BATADV_NO_FLAGS; memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
- if (!batadv_mcast_has_bridge(bat_priv)) + bridged = batadv_mcast_has_bridge(bat_priv); + if (!bridged) goto update;
#if !IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING) pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n"); #endif
+ querier4.exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP); + querier4.shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP); + + querier6.exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6); + querier6.shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6); + mcast_data.flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;
/* 1) If no querier exists at all, then multicast listeners on @@ -327,21 +450,26 @@ static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv) * In both cases, we will signalize other batman nodes that * we need all multicast traffic of the according protocol. */ - if (!br_multicast_has_querier_anywhere(dev, ETH_P_IP) || - br_multicast_has_querier_adjacent(dev, ETH_P_IP)) + if (!querier4.exists || querier4.shadowing) mcast_data.flags |= BATADV_MCAST_WANT_ALL_IPV4;
- if (!br_multicast_has_querier_anywhere(dev, ETH_P_IPV6) || - br_multicast_has_querier_adjacent(dev, ETH_P_IPV6)) + if (!querier6.exists || querier6.shadowing) mcast_data.flags |= BATADV_MCAST_WANT_ALL_IPV6;
update: + batadv_mcast_bridge_log(bat_priv, bridged, &querier4, &querier6); + + bat_priv->mcast.querier_ipv4 = querier4; + bat_priv->mcast.querier_ipv6 = querier6; + if (!bat_priv->mcast.enabled || mcast_data.flags != bat_priv->mcast.flags) { + batadv_mcast_flags_log(bat_priv, mcast_data.flags); batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 1, &mcast_data, sizeof(mcast_data)); bat_priv->mcast.flags = mcast_data.flags; bat_priv->mcast.enabled = true; + bat_priv->mcast.bridged = bridged; }
return !(mcast_data.flags & diff --git a/soft-interface.c b/soft-interface.c index 9bf382d..d4d892c 100644 --- a/soft-interface.c +++ b/soft-interface.c @@ -745,7 +745,12 @@ 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; + bat_priv->mcast.bridged = false; atomic_set(&bat_priv->multicast_mode, 1); atomic_set(&bat_priv->mcast.num_disabled, 0); atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0); diff --git a/types.h b/types.h index 8854c05..b27c79d 100644 --- a/types.h +++ b/types.h @@ -625,14 +625,28 @@ struct batadv_priv_dat {
#ifdef CONFIG_BATMAN_ADV_MCAST /** + * struct batadv_mcast_querier_state - IGMP/MLD querier state when bridged + * @exists: whether a querier exists in the mesh + * @shadowing: if a querier exists, whether it is potentially shadowing + * multicast listeners (i.e. querier is behind our own bridge segment) + */ +struct batadv_mcast_querier_state { + bool exists; + bool shadowing; +}; + +/** * struct batadv_priv_mcast - per mesh interface mcast data * @mla_list: list of multicast addresses we are currently announcing via TT * @want_all_unsnoopables_list: a list of orig_nodes wanting all unsnoopable * multicast traffic * @want_all_ipv4_list: a list of orig_nodes wanting all IPv4 multicast traffic * @want_all_ipv6_list: a list of orig_nodes wanting all IPv6 multicast traffic + * @querier_ipv4: the current state of an IGMP querier in the mesh (if bridged) + * @querier_ipv6: the current state of an MLD querier in the mesh (if bridged) * @flags: the flags we have last sent in our mcast tvlv * @enabled: whether the multicast tvlv is currently enabled + * @bridged: whether the soft interface currently has a bridge on top * @num_disabled: number of nodes that have no mcast tvlv * @num_want_all_unsnoopables: number of nodes wanting unsnoopable IP traffic * @num_want_all_ipv4: counter for items in want_all_ipv4_list @@ -645,8 +659,11 @@ struct batadv_priv_mcast { struct hlist_head want_all_unsnoopables_list; struct hlist_head want_all_ipv4_list; struct hlist_head want_all_ipv6_list; + struct batadv_mcast_querier_state querier_ipv4; + struct batadv_mcast_querier_state querier_ipv6; uint8_t flags; bool enabled; + bool bridged; atomic_t num_disabled; atomic_t num_want_all_unsnoopables; atomic_t num_want_all_ipv4;