[RFC PATCH v4 0/3] expected throughput from AQL airtime

[RFC PATCH v4 0/3] expected throughput from AQL airtime

[Baligh Gasmi]

v4:
- Fix compilation error
- Take into acount channel busy time

v3:
- Update to new MLO sta struct

v2:
- Total size overflow, use u64 instead of u32

v1:
- Make one div after at least 100ms rather than one div each skb

Baligh Gasmi (3):
  mac80211: use AQL airtime for expected throughput.
  mac80211: add periodic monitor for channel busy time
  mac80211: add busy time factor into expected throughput

 net/mac80211/driver-ops.h  |  2 ++
 net/mac80211/ieee80211_i.h |  6 ++++
 net/mac80211/iface.c       | 65 ++++++++++++++++++++++++++++++++++++++
 net/mac80211/sta_info.c    | 46 +++++++++++++++++++++++++++
 net/mac80211/sta_info.h    | 11 +++++++
 net/mac80211/status.c      |  2 ++
 net/mac80211/tx.c          |  8 ++++-
 7 files changed, 139 insertions(+), 1 deletion(-)

-- 
2.36.1

[RFC PATCH v4 1/3] mac80211: use AQL airtime for expected throughput.

[Baligh Gasmi]

Since the integration of AQL, packet TX airtime estimation is
calculated and counted to be used for the dequeue limit.

Use this estimated airtime to compute expected throughput for
each station.

It will be a generic mac80211 implementation. that can be used if the
driver do not have get_expected_throughput implementation.

Useful for L2 routing protocols, like B.A.T.M.A.N.

Signed-off-by: Baligh Gasmi <gasmibal@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
CC: Felix Fietkau <nbd@nbd.name>
---
 net/mac80211/driver-ops.h |  2 ++
 net/mac80211/sta_info.c   | 39 +++++++++++++++++++++++++++++++++++++++
 net/mac80211/sta_info.h   | 11 +++++++++++
 net/mac80211/status.c     |  2 ++
 net/mac80211/tx.c         |  8 +++++++-
 5 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 4e2fc1a08681..fa9952154795 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -1142,6 +1142,8 @@ static inline u32 drv_get_expected_throughput(struct ieee80211_local *local,
 	trace_drv_get_expected_throughput(&sta->sta);
 	if (local->ops->get_expected_throughput && sta->uploaded)
 		ret = local->ops->get_expected_throughput(&local->hw, &sta->sta);
+	else
+		ret = ewma_avg_est_tp_read(&sta->deflink.status_stats.avg_est_tp);
 	trace_drv_return_u32(local, ret);
 
 	return ret;
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index e04a0905e941..201aab465234 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -1993,6 +1993,45 @@ void ieee80211_sta_update_pending_airtime(struct ieee80211_local *local,
 			       tx_pending, 0);
 }
 
+void ieee80211_sta_update_tp(struct ieee80211_local *local,
+			     struct sta_info *sta,
+			     struct sk_buff *skb,
+			     u16 tx_time_est,
+			     bool ack, int retry)
+{
+	unsigned long diff;
+	struct rate_control_ref *ref = NULL;
+
+	if (!skb || !sta || !tx_time_est)
+		return;
+
+	if (test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
+		ref = sta->rate_ctrl;
+
+	if (ref && ref->ops->get_expected_throughput)
+		return;
+
+	if (local->ops->get_expected_throughput)
+		return;
+
+	tx_time_est += ack ? 4 : 0;
+	tx_time_est += retry ? retry * 2 : 2;
+
+	sta->deflink.tx_stats.tp_tx_size += (skb->len * 8) * 1000;
+	sta->deflink.tx_stats.tp_tx_time_est += tx_time_est;
+
+	diff = jiffies - sta->deflink.status_stats.last_tp_update;
+	if (diff > HZ / 10) {
+		ewma_avg_est_tp_add(&sta->deflink.status_stats.avg_est_tp,
+				    sta->deflink.tx_stats.tp_tx_size /
+				    sta->deflink.tx_stats.tp_tx_time_est);
+
+		sta->deflink.tx_stats.tp_tx_size = 0;
+		sta->deflink.tx_stats.tp_tx_time_est = 0;
+		sta->deflink.status_stats.last_tp_update = jiffies;
+	}
+}
+
 int sta_info_move_state(struct sta_info *sta,
 			enum ieee80211_sta_state new_state)
 {
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 35c390bedfba..4200856fefcd 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -123,6 +123,7 @@ enum ieee80211_sta_info_flags {
 #define HT_AGG_STATE_STOP_CB		7
 #define HT_AGG_STATE_SENT_ADDBA		8
 
+DECLARE_EWMA(avg_est_tp, 8, 16)
 DECLARE_EWMA(avg_signal, 10, 8)
 enum ieee80211_agg_stop_reason {
 	AGG_STOP_DECLINED,
@@ -157,6 +158,12 @@ void ieee80211_register_airtime(struct ieee80211_txq *txq,
 
 struct sta_info;
 
+void ieee80211_sta_update_tp(struct ieee80211_local *local,
+			     struct sta_info *sta,
+			     struct sk_buff *skb,
+			     u16 tx_time_est,
+			     bool ack, int retry);
+
 /**
  * struct tid_ampdu_tx - TID aggregation information (Tx).
  *
@@ -549,6 +556,8 @@ struct link_sta_info {
 		s8 last_ack_signal;
 		bool ack_signal_filled;
 		struct ewma_avg_signal avg_ack_signal;
+		struct ewma_avg_est_tp avg_est_tp;
+		unsigned long last_tp_update;
 	} status_stats;
 
 	/* Updated from TX path only, no locking requirements */
@@ -558,6 +567,8 @@ struct link_sta_info {
 		struct ieee80211_tx_rate last_rate;
 		struct rate_info last_rate_info;
 		u64 msdu[IEEE80211_NUM_TIDS + 1];
+		u64 tp_tx_size;
+		u64 tp_tx_time_est;
 	} tx_stats;
 
 	enum ieee80211_sta_rx_bandwidth cur_max_bandwidth;
diff --git a/net/mac80211/status.c b/net/mac80211/status.c
index e69272139437..1fb93abc1709 100644
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -1152,6 +1152,8 @@ void ieee80211_tx_status_ext(struct ieee80211_hw *hw,
 	ack_signal_valid =
 		!!(info->status.flags & IEEE80211_TX_STATUS_ACK_SIGNAL_VALID);
 
+	ieee80211_sta_update_tp(local, sta, skb, tx_time_est, acked, retry_count);
+
 	if (pubsta) {
 		struct ieee80211_sub_if_data *sdata = sta->sdata;
 
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 0e4efc08c762..b7c14ea621de 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -3632,6 +3632,7 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
 	struct ieee80211_tx_data tx;
 	ieee80211_tx_result r;
 	struct ieee80211_vif *vif = txq->vif;
+	struct rate_control_ref *ref = NULL;
 
 	WARN_ON_ONCE(softirq_count() == 0);
 
@@ -3790,8 +3791,13 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
 encap_out:
 	IEEE80211_SKB_CB(skb)->control.vif = vif;
 
+	if (tx.sta && test_sta_flag(tx.sta, WLAN_STA_RATE_CONTROL))
+		ref = tx.sta->rate_ctrl;
+
 	if (vif &&
-	    wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL)) {
+	    ((!local->ops->get_expected_throughput &&
+	     (!ref || !ref->ops->get_expected_throughput)) ||
+	    wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL))) {
 		bool ampdu = txq->ac != IEEE80211_AC_VO;
 		u32 airtime;
 
-- 
2.36.1

[RFC PATCH v4 2/3] mac80211: add periodic monitor for channel busy time

[Baligh Gasmi]

Add a worker scheduled periodicaly to calculate the busy time average of
the current channel.

This will be used in the estimation for expected throughput.

Signed-off-by: Baligh Gasmi <gasmibal@gmail.com>
---
 net/mac80211/ieee80211_i.h |  6 ++++
 net/mac80211/iface.c       | 65 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 86ef0a46a68c..2cb388335ce8 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -901,6 +901,7 @@ struct ieee80211_if_nan {
 	struct idr function_inst_ids;
 };
 
+DECLARE_EWMA(avg_busy, 8, 4)
 struct ieee80211_sub_if_data {
 	struct list_head list;
 
@@ -1024,6 +1025,11 @@ struct ieee80211_sub_if_data {
 	} debugfs;
 #endif
 
+	struct delayed_work monitor_work;
+	u64 last_time;
+	u64 last_time_busy;
+	struct ewma_avg_busy avg_busy;
+
 	/* must be last, dynamically sized area in this! */
 	struct ieee80211_vif vif;
 };
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 41531478437c..45b860c59d79 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1970,6 +1970,64 @@ static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
 	mutex_unlock(&local->iflist_mtx);
 }
 
+#define DEFAULT_MONITOR_INTERVAL_MS 1000
+
+static void ieee80211_if_monitor_work(struct work_struct *work)
+{
+	struct delayed_work *delayed_work = to_delayed_work(work);
+	struct ieee80211_sub_if_data *sdata =
+		container_of(delayed_work, struct ieee80211_sub_if_data,
+			     monitor_work);
+	struct survey_info survey;
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_channel *channel = NULL;
+	int q = 0;
+	u64 interval = DEFAULT_MONITOR_INTERVAL_MS;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (chanctx_conf)
+		channel = chanctx_conf->def.chan;
+	rcu_read_unlock();
+
+	if (!channel)
+		goto end;
+
+	if (!local->started)
+		goto end;
+
+	do {
+		survey.filled = 0;
+		if (drv_get_survey(local, q++, &survey) != 0) {
+			survey.filled = 0;
+			break;
+		}
+	} while (channel != survey.channel);
+
+	if (survey.filled & SURVEY_INFO_TIME) {
+		/* real interval */
+		interval = survey.time - sdata->last_time;
+		/* store last time */
+		sdata->last_time = survey.time;
+	}
+
+	if (survey.filled & SURVEY_INFO_TIME_BUSY) {
+		/* busy */
+		u64 busy = survey.time_busy < sdata->last_time_busy ? 0 :
+			survey.time_busy - sdata->last_time_busy;
+		/* average percent busy time */
+		ewma_avg_busy_add(&sdata->avg_busy,
+				  (busy * 100) / interval);
+		/* store last busy time */
+		sdata->last_time_busy = survey.time_busy;
+	}
+
+end:
+	schedule_delayed_work(&sdata->monitor_work,
+			      msecs_to_jiffies(DEFAULT_MONITOR_INTERVAL_MS));
+}
+
 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 		     unsigned char name_assign_type,
 		     struct wireless_dev **new_wdev, enum nl80211_iftype type,
@@ -2083,6 +2141,8 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 			  ieee80211_dfs_cac_timer_work);
 	INIT_DELAYED_WORK(&sdata->dec_tailroom_needed_wk,
 			  ieee80211_delayed_tailroom_dec);
+	INIT_DELAYED_WORK(&sdata->monitor_work,
+			  ieee80211_if_monitor_work);
 
 	for (i = 0; i < NUM_NL80211_BANDS; i++) {
 		struct ieee80211_supported_band *sband;
@@ -2154,6 +2214,9 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 	list_add_tail_rcu(&sdata->list, &local->interfaces);
 	mutex_unlock(&local->iflist_mtx);
 
+	schedule_delayed_work(&sdata->monitor_work,
+			      msecs_to_jiffies(DEFAULT_MONITOR_INTERVAL_MS));
+
 	if (new_wdev)
 		*new_wdev = &sdata->wdev;
 
@@ -2164,6 +2227,8 @@ void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 {
 	ASSERT_RTNL();
 
+	cancel_delayed_work_sync(&sdata->monitor_work);
+
 	mutex_lock(&sdata->local->iflist_mtx);
 	list_del_rcu(&sdata->list);
 	mutex_unlock(&sdata->local->iflist_mtx);
-- 
2.36.1

Re: [RFC PATCH v4 2/3] mac80211: add periodic monitor for channel busy time

[Kalle Valo]

Baligh Gasmi <gasmibal@gmail.com> writes:

> Add a worker scheduled periodicaly to calculate the busy time average of
> the current channel.
>
> This will be used in the estimation for expected throughput.
>
> Signed-off-by: Baligh Gasmi <gasmibal@gmail.com>

[...]

> --- a/net/mac80211/iface.c
> +++ b/net/mac80211/iface.c
> @@ -1970,6 +1970,64 @@ static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
>  	mutex_unlock(&local->iflist_mtx);
>  }
>  
> +#define DEFAULT_MONITOR_INTERVAL_MS 1000

I'm worried that polling every second affects power consumption.

-- 
https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

[RFC PATCH v4 3/3] mac80211: add busy time factor into expected throughput

[Baligh Gasmi]

When estimating the expected throughput, take into account the busy time
of the current channel.

Signed-off-by: Baligh Gasmi <gasmibal@gmail.com>
---
 net/mac80211/sta_info.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 201aab465234..9f977cf13dd5 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -2000,6 +2000,8 @@ void ieee80211_sta_update_tp(struct ieee80211_local *local,
 			     bool ack, int retry)
 {
 	unsigned long diff;
+	struct ieee80211_sub_if_data *sdata;
+	u32 avg_busy;
 	struct rate_control_ref *ref = NULL;
 
 	if (!skb || !sta || !tx_time_est)
@@ -2014,6 +2016,7 @@ void ieee80211_sta_update_tp(struct ieee80211_local *local,
 	if (local->ops->get_expected_throughput)
 		return;
 
+	sdata = sta->sdata;
 	tx_time_est += ack ? 4 : 0;
 	tx_time_est += retry ? retry * 2 : 2;
 
@@ -2022,6 +2025,10 @@ void ieee80211_sta_update_tp(struct ieee80211_local *local,
 
 	diff = jiffies - sta->deflink.status_stats.last_tp_update;
 	if (diff > HZ / 10) {
+		avg_busy = ewma_avg_busy_read(&sdata->avg_busy) >> 1;
+		sta->deflink.tx_stats.tp_tx_time_est +=
+			(sta->deflin.tx_stats.tp_tx_time_est * avg_busy) / 100;
+
 		ewma_avg_est_tp_add(&sta->deflink.status_stats.avg_est_tp,
 				    sta->deflink.tx_stats.tp_tx_size /
 				    sta->deflink.tx_stats.tp_tx_time_est);
-- 
2.36.1