diff mbox

[5/4] batman-adv: Make hop_penalty configurable via sysfs

Message ID 1286969589-31373-1-git-send-email-linus.luessing@ascom.ch
State Accepted, archived
Commit cb62435257e0b1aab836ae161d6c0a143c77ecf0
Headers show

Commit Message

Linus Lüssing Oct. 13, 2010, 11:33 a.m. UTC
When having a mixed topology of both very mobile and rather static
nodes, you are usually best advised to set the originator interval on
all nodes to a level best suited for the most mobile node.

However, if most of the nodes are rather static, this can create a lot
of undesired overhead as a trade-off then. If setting the interval too
low on the static nodes, a mobile node might be chosen as a router for
too long, not switching away from it fast enough because of its
mobility and the low frequency of ogms of static nodes.

Exposing the hop_penalty is especially useful for the stated scenario: A
static node can keep the default originator interval, a mobile node can
select a quicker one resulting in faster route updates towards this
mobile node. Additionally, such a mobile node could select a higher hop
penalty (or even set it to 255 to disable acting as a router for other
nodes) to make it less desirable, letting other nodes avoid selecting
this mobile node as a router.

Signed-off-by: Linus Lüssing <linus.luessing@ascom.ch>
---
 bat_sysfs.c      |    2 ++
 main.h           |    2 --
 send.c           |    7 ++++---
 soft-interface.c |    1 +
 types.h          |    1 +
 5 files changed, 8 insertions(+), 5 deletions(-)

Comments

Marek Lindner Oct. 15, 2010, 4:01 p.m. UTC | #1
On Wednesday 13 October 2010 13:33:09 Linus Lüssing wrote:
> Exposing the hop_penalty is especially useful for the stated scenario: A
> static node can keep the default originator interval, a mobile node can
> select a quicker one resulting in faster route updates towards this
> mobile node. Additionally, such a mobile node could select a higher hop
> penalty (or even set it to 255 to disable acting as a router for other
> nodes) to make it less desirable, letting other nodes avoid selecting
> this mobile node as a router.

Could you please complete this patch by providing the proper sysfs API 
documentation. For a reference simply check the sysfs-class-net-mesh file which 
is now part of the repository. 

Thanks,
Marek
Marek Lindner Oct. 23, 2010, 1:45 a.m. UTC | #2
On Wednesday 13 October 2010 13:33:09 Linus Lüssing wrote:
> Exposing the hop_penalty is especially useful for the stated scenario: A
> static node can keep the default originator interval, a mobile node can
> select a quicker one resulting in faster route updates towards this
> mobile node. Additionally, such a mobile node could select a higher hop
> penalty (or even set it to 255 to disable acting as a router for other
> nodes) to make it less desirable, letting other nodes avoid selecting
> this mobile node as a router.

Applied in revision 1843.

Thanks,
Marek
diff mbox

Patch

diff --git a/bat_sysfs.c b/bat_sysfs.c
index c20af1f..4e5ba79 100644
--- a/bat_sysfs.c
+++ b/bat_sysfs.c
@@ -298,6 +298,7 @@  BAT_ATTR_BOOL(fragmentation, S_IRUGO | S_IWUSR, update_min_mtu);
 static BAT_ATTR(vis_mode, S_IRUGO | S_IWUSR, show_vis_mode, store_vis_mode);
 static BAT_ATTR(gw_mode, S_IRUGO | S_IWUSR, show_gw_mode, store_gw_mode);
 BAT_ATTR_UINT(orig_interval, S_IRUGO | S_IWUSR, 2 * JITTER, INT_MAX, NULL);
+BAT_ATTR_UINT(hop_penalty, S_IRUGO | S_IWUSR, 0, TQ_MAX_VALUE, NULL);
 #ifdef CONFIG_BATMAN_ADV_DEBUG
 BAT_ATTR_UINT(log_level, S_IRUGO | S_IWUSR, 0, 3, NULL);
 #endif
@@ -309,6 +310,7 @@  static struct bat_attribute *mesh_attrs[] = {
 	&bat_attr_vis_mode,
 	&bat_attr_gw_mode,
 	&bat_attr_orig_interval,
+	&bat_attr_hop_penalty,
 #ifdef CONFIG_BATMAN_ADV_DEBUG
 	&bat_attr_log_level,
 #endif
diff --git a/main.h b/main.h
index cc42eb4..de3c9b9 100644
--- a/main.h
+++ b/main.h
@@ -52,8 +52,6 @@ 
 #define TQ_LOCAL_BIDRECT_RECV_MINIMUM 1
 #define TQ_TOTAL_BIDRECT_LIMIT 1
 
-#define TQ_HOP_PENALTY 10
-
 #define NUM_WORDS (TQ_LOCAL_WINDOW_SIZE / WORD_BIT_SIZE)
 
 #define PACKBUFF_SIZE 2000
diff --git a/send.c b/send.c
index 180e18b..943437b 100644
--- a/send.c
+++ b/send.c
@@ -35,9 +35,10 @@ 
 static void send_outstanding_bcast_packet(struct work_struct *work);
 
 /* apply hop penalty for a normal link */
-static uint8_t hop_penalty(const uint8_t tq)
+static uint8_t hop_penalty(const uint8_t tq, struct bat_priv *bat_priv)
 {
-	return (tq * (TQ_MAX_VALUE - TQ_HOP_PENALTY)) / (TQ_MAX_VALUE);
+	int hop_penalty = atomic_read(&bat_priv->hop_penalty);
+	return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
 }
 
 /* when do we schedule our own packet to be sent */
@@ -339,7 +340,7 @@  void schedule_forward_packet(struct orig_node *orig_node,
 	}
 
 	/* apply hop penalty */
-	batman_packet->tq = hop_penalty(batman_packet->tq);
+	batman_packet->tq = hop_penalty(batman_packet->tq, bat_priv);
 
 	bat_dbg(DBG_BATMAN, bat_priv,
 		"Forwarding packet: tq_orig: %i, tq_avg: %i, "
diff --git a/soft-interface.c b/soft-interface.c
index 7a899b5..69c283c 100644
--- a/soft-interface.c
+++ b/soft-interface.c
@@ -593,6 +593,7 @@  struct net_device *softif_create(char *name)
 	atomic_set(&bat_priv->gw_mode, GW_MODE_OFF);
 	atomic_set(&bat_priv->gw_class, 0);
 	atomic_set(&bat_priv->orig_interval, 1000);
+	atomic_set(&bat_priv->hop_penalty, 10);
 	atomic_set(&bat_priv->log_level, 0);
 	atomic_set(&bat_priv->fragmentation, 1);
 	atomic_set(&bat_priv->bcast_queue_left, BCAST_QUEUE_LEN);
diff --git a/types.h b/types.h
index 44b3c07..299769e 100644
--- a/types.h
+++ b/types.h
@@ -131,6 +131,7 @@  struct bat_priv {
 	atomic_t gw_mode;		/* GW_MODE_* */
 	atomic_t gw_class;		/* uint */
 	atomic_t orig_interval;		/* uint */
+	atomic_t hop_penalty;		/* uint */
 	atomic_t log_level;		/* uint */
 	atomic_t bcast_seqno;
 	atomic_t bcast_queue_left;