On Tue, Feb 11, 2014 at 01:48:14PM +0100, Antonio Quartulli wrote:
From: Antonio Quartulli antonio@open-mesh.com
Implement a stub get_throughput() function which returns the estimated throughput towards a given neighbour. Its result is then used to compute the metric value.
The metric is updated each time a new ELP packet is sent, this way it is possible to timely react to a metric variation which can imply (for example) a neighbour disconnection.
It is very much a style issue, but i would probably split this into two patches. Updating the metric at send time rather than receive should have nothing to do with estimated bandwidth.
Andrew
Signed-off-by: Antonio Quartulli antonio@open-mesh.com
bat_v_elp.c | 49 +++++++++++++++++++++++++++++++++++++++++++------ types.h | 2 ++ 2 files changed, 45 insertions(+), 6 deletions(-)
diff --git a/bat_v_elp.c b/bat_v_elp.c index 4185d8c..ef4e476 100644 --- a/bat_v_elp.c +++ b/bat_v_elp.c @@ -53,6 +53,29 @@ void batadv_elp_neigh_node_free_ref(struct batadv_elp_neigh_node *neigh) }
/**
- batadv_v_elp_get_throughput - get the throughput towards a neighbour
- @neigh: the neighbour for which the throughput has to be obtained
- Returns the throughput towards the given neighbour.
- */
+static uint32_t +batadv_v_elp_get_throughput(struct batadv_elp_neigh_node *neigh) +{
- struct batadv_hard_iface *hard_iface = neigh->hard_iface;
- struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
- uint32_t throughput;
- /* get the customised user value for the throughput */
- throughput = atomic_read(&hard_iface->bat_v.user_throughput);
- /* if the user specified a value, let's return it */
- if (throughput != 0)
return throughput;- /* throughput cannot be computed right now. Return base value */
- return atomic_read(&bat_priv->bat_v.base_throughput);
+}
+/**
- batadv_v_elp_neigh_new - create a new ELP neighbour node
- @hard_iface: the interface the neighbour is connected to
- @neigh_addr: the neighbour interface address
@@ -75,6 +98,7 @@ batadv_v_elp_neigh_new(struct batadv_hard_iface *hard_iface, memcpy(neigh->addr, neigh_addr, ETH_ALEN); neigh->last_seen = jiffies; ewma_init(&neigh->metric, 1024, 8);
- neigh->hard_iface = hard_iface; /* recount initialised to 2 to simplify the caller function */ atomic_set(&neigh->refcount, 2);
@@ -147,19 +171,20 @@ static void batadv_v_elp_neigh_purge(struct batadv_hard_iface *hard_iface) }
/**
- batadv_v_elp_send_outstanding - ELP periodic broadcast sending
- batadv_v_elp_periodic_work - ELP periodic task per interface
- @work: work queue item
- Sends a broadcast ELP message over the interface that this work item belongs
- to.
- Sends a broadcast ELP message and reads the metric for all the neighbours
*/
- connected to the interface that this work item belongs to.
-static void batadv_v_elp_send_outstanding(struct work_struct *work) +static void batadv_v_elp_periodic_work(struct work_struct *work) { struct batadv_hard_iface *hard_iface; struct batadv_hard_iface_bat_v *bat_v; struct batadv_priv *bat_priv; struct batadv_elp_packet *elp_packet; uint32_t elp_interval;
- struct batadv_elp_neigh_node *neigh; struct sk_buff *skb; uint8_t num_neighs;
@@ -181,7 +206,7 @@ static void batadv_v_elp_send_outstanding(struct work_struct *work)
skb = skb_copy(hard_iface->bat_v.elp_skb, GFP_ATOMIC); if (!skb)
goto out;
goto update_metric;/* purge outdated entries first */ batadv_v_elp_neigh_purge(hard_iface);
@@ -204,6 +229,17 @@ static void batadv_v_elp_send_outstanding(struct work_struct *work)
atomic_inc(&hard_iface->bat_v.elp_seqno);
+update_metric:
- /* Instead of updating the metric each "received" ELP packet, it is
* better to do it on each ELP sending. This way, if a node is dead and* does not send packets anymore, batman-adv is still able to timely* react to its death.*/- rcu_read_lock();
- hlist_for_each_entry_rcu(neigh, &hard_iface->bat_v.neigh_list, list)
ewma_add(&neigh->metric, batadv_v_elp_get_throughput(neigh));- rcu_read_unlock();
restart_timer: batadv_v_elp_start_timer(hard_iface); out: @@ -247,7 +283,7 @@ int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface) atomic_set(&hard_iface->bat_v.elp_interval, 500);
INIT_DELAYED_WORK(&hard_iface->bat_v.elp_wq,
batadv_v_elp_send_outstanding);
batadv_v_elp_periodic_work);@@ -332,6 +368,7 @@ static void batadv_v_elp_neigh_update(struct batadv_priv *bat_priv,
neigh->last_seen = jiffies; neigh->last_recv_seqno = ntohl(elp_packet->seqno);
- ewma_add(&neigh->metric, batadv_v_elp_get_throughput(neigh));
out: if (neigh) diff --git a/types.h b/types.h index 54fae29..948d5dc 100644 --- a/types.h +++ b/types.h @@ -345,6 +345,7 @@ struct batadv_gw_node {
- @last_unicast_tx: when the last unicast packet has been sent to this neighbor
- @refcount: number of contexts the object is used
- @rcu: struct used for freeing in an RCU-safe manner
*/
- @hard_iface: the interface where this neighbor is connected to
struct batadv_elp_neigh_node { struct hlist_node list; @@ -357,6 +358,7 @@ struct batadv_elp_neigh_node { unsigned long last_unicast_tx; atomic_t refcount; struct rcu_head rcu;
- struct batadv_hard_iface *hard_iface;
};
/**
1.8.5.3