From 3bda14d09dc5789a895ab02b7dcfcec19b0a65b3 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Linus=20L=C3=BCssing?= Date: Mon, 1 Jun 2020 22:35:22 +0200 Subject: [PATCH] batman-adv: Introduce a configurable per interface hop penalty MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit In some setups multiple hard interfaces with similar link qualities or throughput values are available. But people have expressed the desire to consider one of them as a backup only. Some creative solutions are currently in use: Such people are configuring multiple batman-adv mesh/soft interfaces, wire them together with some veth pairs and then tune the hop penalty to achieve an effect similar to a tunable per interface hop penalty. This patch introduces a new, configurable, per hard interface hop penalty to simplify such setups. Signed-off-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich --- include/uapi/linux/batman_adv.h | 3 ++- net/batman-adv/bat_iv_ogm.c | 17 +++++++++-------- net/batman-adv/bat_v_ogm.c | 13 ++++++++++--- net/batman-adv/hard-interface.c | 2 ++ net/batman-adv/netlink.c | 12 +++++++++++- net/batman-adv/types.h | 6 ++++++ 6 files changed, 40 insertions(+), 13 deletions(-) diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h index 8cf2ad1..bb0ae94 100644 --- a/include/uapi/linux/batman_adv.h +++ b/include/uapi/linux/batman_adv.h @@ -427,7 +427,8 @@ enum batadv_nl_attrs { /** * @BATADV_ATTR_HOP_PENALTY: defines the penalty which will be applied - * to an originator message's tq-field on every hop. + * to an originator message's tq-field on every hop and/or per + * hard interface */ BATADV_ATTR_HOP_PENALTY, diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 5b3a419..a4faf5f 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -1075,10 +1075,10 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, struct batadv_neigh_ifinfo *neigh_ifinfo; u8 total_count; u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own; + unsigned int tq_iface_hop_penalty = BATADV_TQ_MAX_VALUE; unsigned int neigh_rq_inv_cube, neigh_rq_max_cube; unsigned int tq_asym_penalty, inv_asym_penalty; unsigned int combined_tq; - unsigned int tq_iface_penalty; bool ret = false; /* find corresponding one hop neighbor */ @@ -1157,31 +1157,32 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube; inv_asym_penalty /= neigh_rq_max_cube; tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty; + tq_iface_hop_penalty -= atomic_read(&if_incoming->hop_penalty); /* penalize if the OGM is forwarded on the same interface. WiFi * interfaces and other half duplex devices suffer from throughput * drops as they can't send and receive at the same time. */ - tq_iface_penalty = BATADV_TQ_MAX_VALUE; if (if_outgoing && if_incoming == if_outgoing && batadv_is_wifi_hardif(if_outgoing)) - tq_iface_penalty = batadv_hop_penalty(BATADV_TQ_MAX_VALUE, - bat_priv); + tq_iface_hop_penalty = batadv_hop_penalty(tq_iface_hop_penalty, + bat_priv); combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty * - tq_iface_penalty; + tq_iface_hop_penalty; combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE; batadv_ogm_packet->tq = combined_tq; batadv_dbg(BATADV_DBG_BATMAN, bat_priv, - "bidirectional: orig = %pM neigh = %pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, iface_penalty: %3i, total tq: %3i, if_incoming = %s, if_outgoing = %s\n", + "bidirectional: orig = %pM neigh = %pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, iface_hop_penalty: %3i, total tq: %3i, if_incoming = %s, if_outgoing = %s\n", orig_node->orig, orig_neigh_node->orig, total_count, - neigh_rq_count, tq_own, tq_asym_penalty, tq_iface_penalty, - batadv_ogm_packet->tq, if_incoming->net_dev->name, + neigh_rq_count, tq_own, tq_asym_penalty, + tq_iface_hop_penalty, batadv_ogm_packet->tq, + if_incoming->net_dev->name, if_outgoing ? if_outgoing->net_dev->name : "DEFAULT"); /* if link has the minimum required transmission quality diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index 0d404f7..0f8495b 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -455,15 +455,17 @@ unlock: * @throughput: the current throughput * * Apply a penalty on the current throughput metric value based on the - * characteristic of the interface where the OGM has been received. The return - * value is computed as follows: + * characteristic of the interface where the OGM has been received. + * + * Initially the per hardif hop penalty is applied to the throughput. After + * that the return value is then computed as follows: * - throughput * 50% if the incoming and outgoing interface are the * same WiFi interface and the throughput is above * 1MBit/s * - throughput if the outgoing interface is the default * interface (i.e. this OGM is processed for the * internal table and not forwarded) - * - throughput * hop penalty otherwise + * - throughput * node hop penalty otherwise * * Return: the penalised throughput metric. */ @@ -472,9 +474,14 @@ static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv, struct batadv_hard_iface *if_outgoing, u32 throughput) { + int if_hop_penalty = atomic_read(&if_incoming->hop_penalty); int hop_penalty = atomic_read(&bat_priv->hop_penalty); int hop_penalty_max = BATADV_TQ_MAX_VALUE; + /* Apply per hardif hop penalty */ + throughput = throughput * (hop_penalty_max - if_hop_penalty) / + hop_penalty_max; + /* Don't apply hop penalty in default originator table. */ if (if_outgoing == BATADV_IF_DEFAULT) return throughput; diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 53c27c6..fa06b51 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -939,6 +939,8 @@ batadv_hardif_add_interface(struct net_device *net_dev) if (batadv_is_wifi_hardif(hard_iface)) hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; + atomic_set(&hard_iface->hop_penalty, 0); + batadv_v_hardif_init(hard_iface); batadv_check_known_mac_addr(hard_iface->net_dev); diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index cfb00df..dc19361 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -826,6 +826,10 @@ static int batadv_netlink_hardif_fill(struct sk_buff *msg, goto nla_put_failure; } + if (nla_put_u8(msg, BATADV_ATTR_HOP_PENALTY, + atomic_read(&hard_iface->hop_penalty))) + goto nla_put_failure; + #ifdef CONFIG_BATMAN_ADV_BATMAN_V if (nla_put_u32(msg, BATADV_ATTR_ELP_INTERVAL, atomic_read(&hard_iface->bat_v.elp_interval))) @@ -920,9 +924,15 @@ static int batadv_netlink_set_hardif(struct sk_buff *skb, { struct batadv_hard_iface *hard_iface = info->user_ptr[1]; struct batadv_priv *bat_priv = info->user_ptr[0]; + struct nlattr *attr; + + if (info->attrs[BATADV_ATTR_HOP_PENALTY]) { + attr = info->attrs[BATADV_ATTR_HOP_PENALTY]; + + atomic_set(&hard_iface->hop_penalty, nla_get_u8(attr)); + } #ifdef CONFIG_BATMAN_ADV_BATMAN_V - struct nlattr *attr; if (info->attrs[BATADV_ATTR_ELP_INTERVAL]) { attr = info->attrs[BATADV_ATTR_ELP_INTERVAL]; diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index cc151e1..ed519ef 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -208,6 +208,12 @@ struct batadv_hard_iface { /** @rcu: struct used for freeing in an RCU-safe manner */ struct rcu_head rcu; + /** + * @hop_penalty: penalty which will be applied to the tq-field + * of an OGM received via this interface + */ + atomic_t hop_penalty; + /** @bat_iv: per hard-interface B.A.T.M.A.N. IV data */ struct batadv_hard_iface_bat_iv bat_iv; -- 2.7.4