Commit 2265c141 authored by Antonio Quartulli's avatar Antonio Quartulli Committed by Sven Eckelmann

batman-adv: gateway election code refactoring

The gateway election mechanism has been a little revised. Now the
gw_election is trigered by an atomic_t flag (gw_reselect) which is set
to 1 in case of election needed, avoding to set curr_gw to NULL.
Signed-off-by: default avatarAntonio Quartulli <ordex@autistici.org>
Signed-off-by: default avatarMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
parent c6bda689
......@@ -20,6 +20,7 @@
*/
#include "main.h"
#include "bat_sysfs.h"
#include "gateway_client.h"
#include "gateway_common.h"
#include "hard-interface.h"
......@@ -97,40 +98,19 @@ static void gw_select(struct bat_priv *bat_priv, struct gw_node *new_gw_node)
void gw_deselect(struct bat_priv *bat_priv)
{
gw_select(bat_priv, NULL);
atomic_set(&bat_priv->gw_reselect, 1);
}
void gw_election(struct bat_priv *bat_priv)
static struct gw_node *gw_get_best_gw_node(struct bat_priv *bat_priv)
{
struct hlist_node *node;
struct gw_node *gw_node, *curr_gw = NULL, *curr_gw_tmp = NULL;
struct neigh_node *router;
uint8_t max_tq = 0;
struct hlist_node *node;
struct gw_node *gw_node, *curr_gw = NULL;
uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
uint8_t max_tq = 0;
int down, up;
/**
* The batman daemon checks here if we already passed a full originator
* cycle in order to make sure we don't choose the first gateway we
* hear about. This check is based on the daemon's uptime which we
* don't have.
**/
if (atomic_read(&bat_priv->gw_mode) != GW_MODE_CLIENT)
return;
curr_gw = gw_get_selected_gw_node(bat_priv);
if (curr_gw)
goto out;
rcu_read_lock();
if (hlist_empty(&bat_priv->gw_list)) {
bat_dbg(DBG_BATMAN, bat_priv,
"Removing selected gateway - "
"no gateway in range\n");
gw_deselect(bat_priv);
goto unlock;
}
hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
if (gw_node->deleted)
continue;
......@@ -139,6 +119,9 @@ void gw_election(struct bat_priv *bat_priv)
if (!router)
continue;
if (!atomic_inc_not_zero(&gw_node->refcount))
goto next;
switch (atomic_read(&bat_priv->gw_sel_class)) {
case 1: /* fast connection */
gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags,
......@@ -151,8 +134,12 @@ void gw_election(struct bat_priv *bat_priv)
if ((tmp_gw_factor > max_gw_factor) ||
((tmp_gw_factor == max_gw_factor) &&
(router->tq_avg > max_tq)))
curr_gw_tmp = gw_node;
(router->tq_avg > max_tq))) {
if (curr_gw)
gw_node_free_ref(curr_gw);
curr_gw = gw_node;
atomic_inc(&curr_gw->refcount);
}
break;
default: /**
......@@ -163,8 +150,12 @@ void gw_election(struct bat_priv *bat_priv)
* soon as a better gateway appears which has
* $routing_class more tq points)
**/
if (router->tq_avg > max_tq)
curr_gw_tmp = gw_node;
if (router->tq_avg > max_tq) {
if (curr_gw)
gw_node_free_ref(curr_gw);
curr_gw = gw_node;
atomic_inc(&curr_gw->refcount);
}
break;
}
......@@ -174,42 +165,75 @@ void gw_election(struct bat_priv *bat_priv)
if (tmp_gw_factor > max_gw_factor)
max_gw_factor = tmp_gw_factor;
gw_node_free_ref(gw_node);
next:
neigh_node_free_ref(router);
}
rcu_read_unlock();
if (curr_gw != curr_gw_tmp) {
router = orig_node_get_router(curr_gw_tmp->orig_node);
if (!router)
goto unlock;
return curr_gw;
}
void gw_election(struct bat_priv *bat_priv)
{
struct gw_node *curr_gw = NULL, *next_gw = NULL;
struct neigh_node *router = NULL;
/**
* The batman daemon checks here if we already passed a full originator
* cycle in order to make sure we don't choose the first gateway we
* hear about. This check is based on the daemon's uptime which we
* don't have.
**/
if (atomic_read(&bat_priv->gw_mode) != GW_MODE_CLIENT)
goto out;
if (!atomic_dec_not_zero(&bat_priv->gw_reselect))
goto out;
if ((curr_gw) && (!curr_gw_tmp))
curr_gw = gw_get_selected_gw_node(bat_priv);
next_gw = gw_get_best_gw_node(bat_priv);
if (curr_gw == next_gw)
goto out;
if (next_gw) {
router = orig_node_get_router(next_gw->orig_node);
if (!router) {
gw_deselect(bat_priv);
goto out;
}
}
if ((curr_gw) && (!next_gw)) {
bat_dbg(DBG_BATMAN, bat_priv,
"Removing selected gateway - "
"no gateway in range\n");
else if ((!curr_gw) && (curr_gw_tmp))
"Removing selected gateway - no gateway in range\n");
} else if ((!curr_gw) && (next_gw)) {
bat_dbg(DBG_BATMAN, bat_priv,
"Adding route to gateway %pM "
"(gw_flags: %i, tq: %i)\n",
curr_gw_tmp->orig_node->orig,
curr_gw_tmp->orig_node->gw_flags,
"Adding route to gateway %pM (gw_flags: %i, tq: %i)\n",
next_gw->orig_node->orig,
next_gw->orig_node->gw_flags,
router->tq_avg);
else
} else {
bat_dbg(DBG_BATMAN, bat_priv,
"Changing route to gateway %pM "
"(gw_flags: %i, tq: %i)\n",
curr_gw_tmp->orig_node->orig,
curr_gw_tmp->orig_node->gw_flags,
next_gw->orig_node->orig,
next_gw->orig_node->gw_flags,
router->tq_avg);
neigh_node_free_ref(router);
gw_select(bat_priv, curr_gw_tmp);
}
unlock:
rcu_read_unlock();
gw_select(bat_priv, next_gw);
out:
if (curr_gw)
gw_node_free_ref(curr_gw);
if (next_gw)
gw_node_free_ref(next_gw);
if (router)
neigh_node_free_ref(router);
}
void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node)
......
......@@ -113,6 +113,7 @@ int mesh_init(struct net_device *soft_iface)
if (vis_init(bat_priv) < 1)
goto err;
atomic_set(&bat_priv->gw_reselect, 0);
atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
goto end;
......
......@@ -201,6 +201,7 @@ struct bat_priv {
struct delayed_work orig_work;
struct delayed_work vis_work;
struct gw_node __rcu *curr_gw; /* rcu protected pointer */
atomic_t gw_reselect;
struct hard_iface __rcu *primary_if; /* rcu protected pointer */
struct vis_info *my_vis_info;
};
......
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