From: Antonio Quartulli ordex@autistici.org
In case of new default gw, changing the default gw or deleting the default gw a uevent is triggered with type=gw, action=add/change/del and data={GW_ORIG_ADDRESS} (if any).
The gateway election mechanism has been a little revised. Now the gw_election is trigered by an atomic_t flag (gw_reselect) which is is set to 1 in case of election needed, avoding to set curr_gw to NULL.
Signed-off-by: Antonio Quartulli ordex@autistici.org Signed-off-by: Marek Lindner lindner_marek@yahoo.de --- * gw_election() code refactored to increase readability * bug fixed: if curr_gw_tmp is NULL the uevent would never be triggered because the variable "router" would also be NULL
gateway_client.c | 143 ++++++++++++++++++++++++++++++++--------------------- main.c | 1 + types.h | 1 + 3 files changed, 88 insertions(+), 57 deletions(-)
diff --git a/gateway_client.c b/gateway_client.c index 24aee56..964a27e 100644 --- a/gateway_client.c +++ b/gateway_client.c @@ -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 +165,80 @@ void gw_election(struct bat_priv *bat_priv) if (tmp_gw_factor > max_gw_factor) max_gw_factor = tmp_gw_factor;
+next: neigh_node_free_ref(router); + gw_node_free_ref(gw_node); } + 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; +}
- if ((curr_gw) && (!curr_gw_tmp)) - bat_dbg(DBG_BATMAN, bat_priv, - "Removing selected gateway - " - "no gateway in range\n"); - else if ((!curr_gw) && (curr_gw_tmp)) - 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, - router->tq_avg); - 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, - router->tq_avg); +void gw_election(struct bat_priv *bat_priv) +{ + struct gw_node *curr_gw = NULL, *next_gw = NULL; + struct neigh_node *router = NULL; + char gw_addr[18] = { '\0' };
- neigh_node_free_ref(router); - gw_select(bat_priv, curr_gw_tmp); + /** + * 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; + + 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) { + sprintf(gw_addr, "%pM", next_gw->orig_node->orig); + + router = orig_node_get_router(next_gw->orig_node); + if (!router) { + gw_deselect(bat_priv); + goto out; + } }
-unlock: - rcu_read_unlock(); + if ((curr_gw) && (!next_gw)) { + bat_dbg(DBG_BATMAN, bat_priv, + "Removing selected gateway - no gateway in range\n"); + throw_uevent(bat_priv, UEV_GW, UEV_DEL, NULL); + } else if ((!curr_gw) && (next_gw)) { + bat_dbg(DBG_BATMAN, bat_priv, + "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); + throw_uevent(bat_priv, UEV_GW, UEV_ADD, gw_addr); + } else { + bat_dbg(DBG_BATMAN, bat_priv, + "Changing route to gateway %pM " + "(gw_flags: %i, tq: %i)\n", + next_gw->orig_node->orig, + next_gw->orig_node->gw_flags, + router->tq_avg); + throw_uevent(bat_priv, UEV_GW, UEV_CHANGE, gw_addr); + } + + 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) diff --git a/main.c b/main.c index c2b06b7..e367e69 100644 --- a/main.c +++ b/main.c @@ -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;
diff --git a/types.h b/types.h index 11e8569..85cf122 100644 --- a/types.h +++ b/types.h @@ -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; };