[B.A.T.M.A.N.] [PATCHv4 2/3] mac80211: export the expected throughput

Antonio Quartulli
2014-05-19T19:53:20Z

Add get_expected_throughput() API to mac80211 so that each
driver can implement its own version based on the RC
algorithm they are using (might be using an HW RC algo).
The API returns a value expressed in Kbps.

Also, add the new get_expected_throughput() member
to the rate_control_ops structure in order to be
able to query the RC algorithm (this patch provides an
implementation of this API for both minstrel and
minstrel_ht).

The related member in the station_info object is now
filled accordingly when dumping a station.

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---
include/net/mac80211.h | 7 +++++++
net/mac80211/cfg.c | 19 +++++++++++++++++++
net/mac80211/driver-ops.h | 13 +++++++++++++
net/mac80211/rc80211_minstrel.c | 12 ++++++++++++
net/mac80211/rc80211_minstrel_ht.c | 17 +++++++++++++++++
net/mac80211/trace.h | 32 ++++++++++++++++++++++++++++++++
6 files changed, 100 insertions(+)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index a34f26a..2c78997 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2769,6 +2769,10 @@ enum ieee80211_roc_type {
* information in bss_conf is set up and the beacon can be retrieved. A
* channel context is bound before this is called.
* @leave_ibss: Leave the IBSS again.
+ *
+ * @get_expected_throughput: extract the expected throughput towards the
+ * specified station. The returned value is expressed in Kbps. It returns 0
+ * if the RC algorithm does not have proper data to provide.
*/
struct ieee80211_ops {
void (*tx)(struct ieee80211_hw *hw,
@@ -2962,6 +2966,7 @@ struct ieee80211_ops {

int (*join_ibss)(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
void (*leave_ibss)(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
+ u32 (*get_expected_throughput)(struct ieee80211_sta *sta);
};

/**
@@ -4535,6 +4540,8 @@ struct rate_control_ops {
void (*add_sta_debugfs)(void *priv, void *priv_sta,
struct dentry *dir);
void (*remove_sta_debugfs)(void *priv, void *priv_sta);
+
+ u32 (*get_expected_throughput)(void *priv_sta);
};

static inline int rate_supported(struct ieee80211_sta *sta,
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index ac45304..9e86dd5 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -472,8 +472,12 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
+ struct rate_control_ref *ref = local->rate_ctrl;
+ struct ieee80211_supported_band *sband;
+ enum ieee80211_band band;
struct timespec uptime;
u64 packets = 0;
+ u32 thr = 0;
int i, ac;

sinfo->generation = sdata->local->sta_generation;
@@ -587,6 +591,21 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_ASSOCIATED);
if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
+
+ /* check if the driver has a SW RC implementation */
+ if (ref && ref->ops->get_expected_throughput) {
+ band = ieee80211_get_sdata_band(sta->sdata);
+ sband = sta->local->hw.wiphy->bands[band];
+
+ thr = ref->ops->get_expected_throughput(sta->rate_ctrl_priv);
+ } else {
+ thr = drv_get_expected_throughput(local, &sta->sta);
+ }
+
+ if (thr != 0) {
+ sinfo->filled |= STATION_INFO_EXPECTED_THROUGHPUT;
+ sinfo->expected_throughput = thr;
+ }
}

static const char ieee80211_gstrings_sta_stats[][ETH_GSTRING_LEN] = {
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index df1d502..696ef78 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -1156,4 +1156,17 @@ static inline void drv_leave_ibss(struct ieee80211_local *local,
trace_drv_return_void(local);
}

+static inline u32 drv_get_expected_throughput(struct ieee80211_local *local,
+ struct ieee80211_sta *sta)
+{
+ u32 ret = 0;
+
+ trace_drv_get_expected_throughput(sta);
+ if (local->ops->get_expected_throughput)
+ ret = local->ops->get_expected_throughput(sta);
+ trace_drv_return_u32(local, ret);
+
+ return ret;
+}
+
#endif /* __MAC80211_DRIVER_OPS */
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index 26fd94f..1c1469c 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -657,6 +657,17 @@ minstrel_free(void *priv)
kfree(priv);
}

+static u32 minstrel_get_expected_throughput(void *priv_sta)
+{
+ struct minstrel_sta_info *mi = priv_sta;
+ int idx = mi->max_tp_rate[0];
+
+ /* convert pkt per sec in kbps (1200 is the average pkt size used for
+ * computing cur_tp
+ */
+ return MINSTREL_TRUNC(mi->r[idx].cur_tp) * 1200 * 8 / 1024;
+}
+
const struct rate_control_ops mac80211_minstrel = {
.name = "minstrel",
.tx_status = minstrel_tx_status,
@@ -670,6 +681,7 @@ const struct rate_control_ops mac80211_minstrel = {
.add_sta_debugfs = minstrel_add_sta_debugfs,
.remove_sta_debugfs = minstrel_remove_sta_debugfs,
#endif
+ .get_expected_throughput = minstrel_get_expected_throughput,
};

int __init
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 4e916ad..85c1e74 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -1032,6 +1032,22 @@ minstrel_ht_free(void *priv)
mac80211_minstrel.free(priv);
}

+static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
+{
+ struct minstrel_ht_sta_priv *msp = priv_sta;
+ struct minstrel_ht_sta *mi = &msp->ht;
+ int i, j;
+
+ if (!msp->is_ht)
+ return mac80211_minstrel.get_expected_throughput(priv_sta);
+
+ i = mi->max_tp_rate / MCS_GROUP_RATES;
+ j = mi->max_tp_rate % MCS_GROUP_RATES;
+
+ /* convert cur_tp from pkt per second in kbps */
+ return mi->groups[i].rates[j].cur_tp * AVG_PKT_SIZE * 8 / 1024;
+}
+
static const struct rate_control_ops mac80211_minstrel_ht = {
.name = "minstrel_ht",
.tx_status = minstrel_ht_tx_status,
@@ -1046,6 +1062,7 @@ static const struct rate_control_ops mac80211_minstrel_ht = {
.add_sta_debugfs = minstrel_ht_add_sta_debugfs,
.remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
#endif
+ .get_expected_throughput = minstrel_ht_get_expected_throughput,
};

diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h
index a0b0aea..942f64b 100644
--- a/net/mac80211/trace.h
+++ b/net/mac80211/trace.h
@@ -184,6 +184,20 @@ TRACE_EVENT(drv_return_bool,
"true" : "false")
);

+TRACE_EVENT(drv_return_u32,
+ TP_PROTO(struct ieee80211_local *local, u32 ret),
+ TP_ARGS(local, ret),
+ TP_STRUCT__entry(
+ LOCAL_ENTRY
+ __field(u32, ret)
+ ),
+ TP_fast_assign(
+ LOCAL_ASSIGN;
+ __entry->ret = ret;
+ ),
+ TP_printk(LOCAL_PR_FMT " - %u", LOCAL_PR_ARG, __entry->ret)
+);
+
TRACE_EVENT(drv_return_u64,
TP_PROTO(struct ieee80211_local *local, u64 ret),
TP_ARGS(local, ret),
@@ -1499,6 +1513,24 @@ DEFINE_EVENT(local_sdata_evt, drv_leave_ibss,
TP_ARGS(local, sdata)
);

+TRACE_EVENT(drv_get_expected_throughput,
+ TP_PROTO(struct ieee80211_sta *sta),
+
+ TP_ARGS(sta),
+
+ TP_STRUCT__entry(
+ STA_ENTRY
+ ),
+
+ TP_fast_assign(
+ STA_ASSIGN;
+ ),
+
+ TP_printk(
+ STA_PR_FMT, STA_PR_ARG
+ )
+);
+
/*
* Tracing for API calls that drivers call.
*/
--
1.8.5.5