batman-adv: B.A.T.M.A.N. V - implement GW selection logic (50164d8f) · Commits · e / devices / android_kernel_oneplus_sm8150

net/batman-adv/bat_v.c

+222 −1

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@
		#include <linux/init.h>
		#include <linux/jiffies.h>
		#include <linux/kernel.h>
		#include <linux/kref.h>
		#include <linux/netdevice.h>
		#include <linux/rculist.h>
		#include <linux/rcupdate.h>
		@@ -40,6 +41,7 @@
		#include "gateway_common.h"
		#include "hard-interface.h"
		#include "hash.h"
		#include "log.h"
		#include "originator.h"
		#include "packet.h"

		@@ -350,6 +352,213 @@ static ssize_t batadv_v_show_sel_class(struct batadv_priv bat_priv, char buff)
		return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
		}

		/**
		* batadv_v_gw_throughput_get - retrieve the GW-bandwidth for a given GW
		* @gw_node: the GW to retrieve the metric for
		* @bw: the pointer where the metric will be stored. The metric is computed as
		* the minimum between the GW advertised throughput and the path throughput to
		* it in the mesh
		*
		* Return: 0 on success, -1 on failure
		*/
		static int batadv_v_gw_throughput_get(struct batadv_gw_node gw_node, u32 bw)
		{
		struct batadv_neigh_ifinfo *router_ifinfo = NULL;
		struct batadv_orig_node *orig_node;
		struct batadv_neigh_node *router;
		int ret = -1;

		orig_node = gw_node->orig_node;
		router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
		if (!router)
		goto out;

		router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
		if (!router_ifinfo)
		goto out;

		/* the GW metric is computed as the minimum between the path throughput
		* to reach the GW itself and the advertised bandwidth.
		* This gives us an approximation of the effective throughput that the
		* client can expect via this particular GW node
		*/
		*bw = router_ifinfo->bat_v.throughput;
		bw = min_t(u32, bw, gw_node->bandwidth_down);

		ret = 0;
		out:
		if (router)
		batadv_neigh_node_put(router);
		if (router_ifinfo)
		batadv_neigh_ifinfo_put(router_ifinfo);

		return ret;
		}

		/**
		* batadv_v_gw_get_best_gw_node - retrieve the best GW node
		* @bat_priv: the bat priv with all the soft interface information
		*
		* Return: the GW node having the best GW-metric, NULL if no GW is known
		*/
		static struct batadv_gw_node *
		batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
		{
		struct batadv_gw_node gw_node, curr_gw = NULL;
		u32 max_bw = 0, bw;

		rcu_read_lock();
		hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
		if (!kref_get_unless_zero(&gw_node->refcount))
		continue;

		if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
		goto next;

		if (curr_gw && (bw <= max_bw))
		goto next;

		if (curr_gw)
		batadv_gw_node_put(curr_gw);

		curr_gw = gw_node;
		kref_get(&curr_gw->refcount);
		max_bw = bw;

		next:
		batadv_gw_node_put(gw_node);
		}
		rcu_read_unlock();

		return curr_gw;
		}

		/**
		* batadv_v_gw_is_eligible - check if a originator would be selected as GW
		* @bat_priv: the bat priv with all the soft interface information
		* @curr_gw_orig: originator representing the currently selected GW
		* @orig_node: the originator representing the new candidate
		*
		* Return: true if orig_node can be selected as current GW, false otherwise
		*/
		static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
		struct batadv_orig_node *curr_gw_orig,
		struct batadv_orig_node *orig_node)
		{
		struct batadv_gw_node curr_gw = NULL, orig_gw = NULL;
		u32 gw_throughput, orig_throughput, threshold;
		bool ret = false;

		threshold = atomic_read(&bat_priv->gw.sel_class);

		curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
		if (!curr_gw) {
		ret = true;
		goto out;
		}

		if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
		ret = true;
		goto out;
		}

		orig_gw = batadv_gw_node_get(bat_priv, orig_node);
		if (!orig_node)
		goto out;

		if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
		goto out;

		if (orig_throughput < gw_throughput)
		goto out;

		if ((orig_throughput - gw_throughput) < threshold)
		goto out;

		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		"Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
		gw_throughput, orig_throughput);

		ret = true;
		out:
		if (curr_gw)
		batadv_gw_node_put(curr_gw);
		if (orig_gw)
		batadv_gw_node_put(orig_gw);

		return ret;
		}

		/* fails if orig_node has no router */
		static int batadv_v_gw_write_buffer_text(struct batadv_priv *bat_priv,
		struct seq_file *seq,
		const struct batadv_gw_node *gw_node)
		{
		struct batadv_gw_node *curr_gw;
		struct batadv_neigh_node *router;
		struct batadv_neigh_ifinfo *router_ifinfo = NULL;
		int ret = -1;

		router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
		if (!router)
		goto out;

		router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
		if (!router_ifinfo)
		goto out;

		curr_gw = batadv_gw_get_selected_gw_node(bat_priv);

		seq_printf(seq, "%s %pM (%9u.%1u) %pM [%10s]: %u.%u/%u.%u MBit\n",
		(curr_gw == gw_node ? "=>" : " "),
		gw_node->orig_node->orig,
		router_ifinfo->bat_v.throughput / 10,
		router_ifinfo->bat_v.throughput % 10, router->addr,
		router->if_incoming->net_dev->name,
		gw_node->bandwidth_down / 10,
		gw_node->bandwidth_down % 10,
		gw_node->bandwidth_up / 10,
		gw_node->bandwidth_up % 10);
		ret = seq_has_overflowed(seq) ? -1 : 0;

		if (curr_gw)
		batadv_gw_node_put(curr_gw);
		out:
		if (router_ifinfo)
		batadv_neigh_ifinfo_put(router_ifinfo);
		if (router)
		batadv_neigh_node_put(router);
		return ret;
		}

		/**
		* batadv_v_gw_print - print the gateway list
		* @bat_priv: the bat priv with all the soft interface information
		* @seq: gateway table seq_file struct
		*/
		static void batadv_v_gw_print(struct batadv_priv *bat_priv,
		struct seq_file *seq)
		{
		struct batadv_gw_node *gw_node;
		int gw_count = 0;

		seq_puts(seq,
		" Gateway ( throughput) Nexthop [outgoingIF]: advertised uplink bandwidth\n");

		rcu_read_lock();
		hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
		/* fails if orig_node has no router */
		if (batadv_v_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
		continue;

		gw_count++;
		}
		rcu_read_unlock();

		if (gw_count == 0)
		seq_puts(seq, "No gateways in range ...\n");
		}

		static struct batadv_algo_ops batadv_batman_v __read_mostly = {
		.name = "BATMAN_V",
		.iface = {
		@@ -371,6 +580,9 @@ static struct batadv_algo_ops batadv_batman_v __read_mostly = {
		.gw = {
		.store_sel_class = batadv_v_store_sel_class,
		.show_sel_class = batadv_v_show_sel_class,
		.get_best_gw_node = batadv_v_gw_get_best_gw_node,
		.is_eligible = batadv_v_gw_is_eligible,
		.print = batadv_v_gw_print,
		},
		};

		@@ -397,7 +609,16 @@ void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface)
		*/
		int batadv_v_mesh_init(struct batadv_priv *bat_priv)
		{
		return batadv_v_ogm_init(bat_priv);
		int ret = 0;

		ret = batadv_v_ogm_init(bat_priv);
		if (ret < 0)
		return ret;

		/* set default throughput difference threshold to 5Mbps */
		atomic_set(&bat_priv->gw.sel_class, 50);

		return 0;
		}

		/**

net/batman-adv/gateway_client.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -360,8 +360,7 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
		*
		* Return: gateway node if found or NULL otherwise.
		*/
		static struct batadv_gw_node *
		batadv_gw_node_get(struct batadv_priv *bat_priv,
		struct batadv_gw_node batadv_gw_node_get(struct batadv_priv bat_priv,
		struct batadv_orig_node *orig_node)
		{
		struct batadv_gw_node gw_node_tmp, gw_node = NULL;

net/batman-adv/gateway_client.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -47,5 +47,7 @@ bool batadv_gw_out_of_range(struct batadv_priv bat_priv, struct sk_buff skb);
		enum batadv_dhcp_recipient
		batadv_gw_dhcp_recipient_get(struct sk_buff skb, unsigned int header_len,
		u8 *chaddr);
		struct batadv_gw_node batadv_gw_node_get(struct batadv_priv bat_priv,
		struct batadv_orig_node *orig_node);

		#endif /* _NET_BATMAN_ADV_GATEWAY_CLIENT_H_ */