[B.A.T.M.A.N.] [PATCH v2 6/7] batman-adv: ELP - use tp meter to estimate the throughput if otherwise not available

Marek Lindner
2018-05-18T01:47:53Z

Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
---
net/batman-adv/bat_v_elp.c | 63 ++++++++++++++++++++++++++++++++++++--
net/batman-adv/bat_v_elp.h | 21 +++++++++++++
net/batman-adv/main.h | 1 +
net/batman-adv/tp_meter.c | 37 +++++++++++++++++-----
net/batman-adv/types.h | 14 +++++++++
5 files changed, 126 insertions(+), 10 deletions(-)

diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index 71c20c1d..3f0d7816 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -51,6 +51,7 @@
#include "originator.h"
#include "routing.h"
#include "send.h"
+#include "tp_meter.h"

/**
* batadv_v_elp_start_timer() - restart timer for ELP periodic work
@@ -67,6 +68,41 @@ static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface)
msecs_to_jiffies(msecs));
}

+/**
+ * batadv_v_elp_tp_start() - start a tp meter session for a neighbor
+ * @neigh: neighbor to run tp meter on
+ */
+static void batadv_v_elp_tp_start(struct batadv_hardif_neigh_node *neigh)
+{
+ struct batadv_hard_iface *hard_iface = neigh->if_incoming;
+ struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+
+ neigh->bat_v.tp_meter_running = true;
+ batadv_tp_start(bat_priv, neigh->addr, neigh, 10, NULL, BATADV_TP_ELP);
+}
+
+/**
+ * batadv_v_elp_tp_fail() - handle tp meter session failure
+ * @neigh: neighbor to run tp meter on
+ */
+void batadv_v_elp_tp_fail(struct batadv_hardif_neigh_node *neigh)
+{
+ neigh->bat_v.tp_meter_running = false;
+}
+
+/**
+ * batadv_v_elp_tp_finish() - post-process tp meter results
+ * @neigh: neighbor tp meter on
+ * @throughput: tp meter throughput result
+ */
+void batadv_v_elp_tp_finish(struct batadv_hardif_neigh_node *neigh,
+ u32 throughput)
+{
+ neigh->bat_v.tp_meter_throughput = throughput;
+ neigh->bat_v.last_tp_meter_run = jiffies;
+ neigh->bat_v.tp_meter_running = false;
+}
+
/**
* batadv_v_elp_get_throughput() - get the throughput towards a neighbour
* @neigh: the neighbour for which the throughput has to be obtained
@@ -78,6 +114,7 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
{
struct batadv_hard_iface *hard_iface = neigh->if_incoming;
struct ethtool_link_ksettings link_settings;
+ u32 last_tp_run_msecs, last_tp_run_jiffies;
struct net_device *real_netdev;
struct station_info sinfo;
u32 throughput;
@@ -112,10 +149,13 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
*/
return 0;
}
+
+ /* unsupported WiFi driver */
if (ret)
- goto default_throughput;
+ goto fallback_throughput;
+
if (!(sinfo.filled & BIT(NL80211_STA_INFO_EXPECTED_THROUGHPUT)))
- goto default_throughput;
+ goto fallback_throughput;

return sinfo.expected_throughput / 100;
}
@@ -152,6 +192,25 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
return throughput * 10;
}

+fallback_throughput:
+ last_tp_run_jiffies = jiffies - neigh->bat_v.last_tp_meter_run;
+ last_tp_run_msecs = jiffies_to_msecs(last_tp_run_jiffies);
+
+ /* check the tp_meter_running flag before checking the timestamp to
+ * avoid a race condition where a new tp meter session is scheduled
+ * right after the previous tp meter session has completed
+ */
+ if (!neigh->bat_v.tp_meter_running &&
+ last_tp_run_msecs > BATADV_ELP_TP_RUN_INTERVAL)
+ batadv_v_elp_tp_start(neigh);
+
+ /* discard too old tp test results */
+ if (last_tp_run_msecs > 2 * BATADV_ELP_TP_RUN_INTERVAL)
+ neigh->bat_v.tp_meter_throughput = 0;
+
+ if (neigh->bat_v.tp_meter_throughput)
+ return neigh->bat_v.tp_meter_throughput;
+
default_throughput:
if (!(hard_iface->bat_v.flags & BATADV_WARNING_DEFAULT)) {
batadv_info(hard_iface->soft_iface,
diff --git a/net/batman-adv/bat_v_elp.h b/net/batman-adv/bat_v_elp.h
index e8c7b7fd..4ffb1fde 100644
--- a/net/batman-adv/bat_v_elp.h
+++ b/net/batman-adv/bat_v_elp.h
@@ -21,6 +21,8 @@

#include "main.h"

+#include <linux/types.h>
+
struct sk_buff;
struct work_struct;

@@ -33,4 +35,23 @@ int batadv_v_elp_packet_recv(struct sk_buff *skb,
struct batadv_hard_iface *if_incoming);
void batadv_v_elp_throughput_metric_update(struct work_struct *work);

+#ifdef CONFIG_BATMAN_ADV_BATMAN_V
+
+void batadv_v_elp_tp_fail(struct batadv_hardif_neigh_node *neigh);
+void batadv_v_elp_tp_finish(struct batadv_hardif_neigh_node *neigh,
+ u32 throughput);
+
+#else
+
+static inline void batadv_v_elp_tp_fail(struct batadv_hardif_neigh_node *neigh)
+{
+}
+
+static inline void
+batadv_v_elp_tp_finish(struct batadv_hardif_neigh_node *neigh, u32 throughput)
+{
+}
+
+#endif /* CONFIG_BATMAN_ADV_BATMAN_V */
+
#endif /* _NET_BATMAN_ADV_BAT_V_ELP_H_ */
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index 89dfaf87..ed4ae913 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -69,6 +69,7 @@
#define BATADV_ELP_MIN_PROBE_SIZE 200 /* bytes */
#define BATADV_ELP_PROBE_MAX_TX_DIFF 100 /* milliseconds */
#define BATADV_ELP_MAX_AGE 64
+#define BATADV_ELP_TP_RUN_INTERVAL 60000 /* milliseconds */
#define BATADV_OGM_MAX_ORIGDIFF 5
#define BATADV_OGM_MAX_AGE 64

diff --git a/net/batman-adv/tp_meter.c b/net/batman-adv/tp_meter.c
index 87aaeb1d..ec47ca79 100644
--- a/net/batman-adv/tp_meter.c
+++ b/net/batman-adv/tp_meter.c
@@ -24,7 +24,7 @@
#include <linux/byteorder/generic.h>
#include <linux/cache.h>
#include <linux/compiler.h>
-#include <linux/err.h>
+#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/gfp.h>
#include <linux/if_ether.h>
@@ -33,9 +33,9 @@
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
+#include <linux/log2.h>
#include <linux/netdevice.h>
#include <linux/param.h>
-#include <linux/printk.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
@@ -51,6 +51,7 @@
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>

+#include "bat_v_elp.h"
#include "hard-interface.h"
#include "log.h"
#include "netlink.h"
@@ -225,6 +226,7 @@ static void batadv_tp_caller_notify(struct batadv_priv *bat_priv,
enum batadv_tp_meter_reason reason)
{
u32 total_bytes;
+ u64 throughput;
u32 test_time;
u32 cookie;
bool reason_is_error;
@@ -251,6 +253,21 @@ static void batadv_tp_caller_notify(struct batadv_priv *bat_priv,

break;
case BATADV_TP_ELP:
+ if (reason_is_error) {
+ batadv_v_elp_tp_fail(tp_vars->hardif_neigh);
+ return;
+ }
+
+ test_time = jiffies_to_msecs(jiffies - tp_vars->start_time);
+ total_bytes = atomic64_read(&tp_vars->tot_sent);
+
+ /* The following calculation includes these steps:
+ * - convert bytes to bits
+ * - divide bits by the test length (msecs)
+ * - convert result from bits/ms to 0.1Mb/s (* 1024 * 10 / 1000)
+ */
+ throughput = total_bytes * 8 >> ilog2(test_time) / 10;
+ batadv_v_elp_tp_finish(tp_vars->hardif_neigh, throughput);
break;
default:
break;
@@ -264,11 +281,14 @@ static void batadv_tp_caller_notify(struct batadv_priv *bat_priv,
* @reason: reason for tp meter session stop
* @dst: destination of tp_meter session
* @cookie: cookie of tp_meter session
+ * @hardif_neigh: neighbor towards which the test was ran (for one-hop test)
*/
-static void batadv_tp_caller_init_error(struct batadv_priv *bat_priv,
- enum batadv_tp_meter_caller caller,
- enum batadv_tp_meter_reason reason,
- const u8 *dst, u32 cookie)
+static void
+batadv_tp_caller_init_error(struct batadv_priv *bat_priv,
+ enum batadv_tp_meter_caller caller,
+ enum batadv_tp_meter_reason reason, const u8 *dst,
+ u32 cookie,
+ struct batadv_hardif_neigh_node *hardif_neigh)
{
switch (caller) {
case BATADV_TP_USERSPACE:
@@ -276,6 +296,7 @@ static void batadv_tp_caller_init_error(struct batadv_priv *bat_priv,
cookie);
break;
case BATADV_TP_ELP:
+ batadv_v_elp_tp_fail(hardif_neigh);
break;
default:
break;
@@ -981,7 +1002,7 @@ void batadv_tp_start(struct batadv_priv *bat_priv, const u8 *dst,
"Meter: too many ongoing sessions, aborting (SEND)\n");
batadv_tp_caller_init_error(bat_priv, caller,
BATADV_TP_REASON_TOO_MANY, dst,
- session_cookie);
+ session_cookie, neigh);
return;
}

@@ -989,7 +1010,7 @@ void batadv_tp_start(struct batadv_priv *bat_priv, const u8 *dst,
if (!tp_vars) {
batadv_tp_caller_init_error(bat_priv, caller,
BATADV_TP_REASON_MEMORY_ERROR, dst,
- session_cookie);
+ session_cookie, neigh);
return;
}

diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 0a9bee88..148f23ad 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -583,6 +583,20 @@ struct batadv_hardif_neigh_node_bat_v {

/** @metric_work: work queue callback item for metric update */
struct work_struct metric_work;
+
+ /**
+ * @tp_meter_running: tp meter measurements towards this neighbor in
+ * progress
+ */
+ unsigned char tp_meter_running:1;
+
+ /**
+ * @last_tp_meter_run: timestamp of last tp meter measurement completion
+ */
+ unsigned long last_tp_meter_run;
+
+ /** @tp_meter_throughput: throughput information measured by tp meter */
+ unsigned long tp_meter_throughput;
};

/**
--
2.17.0