2022-07-19 13:56:14

by Baligh GASMI

[permalink] [raw]
Subject: [RFC/RFT v5 0/4] expected throughput from AQL airtime

v5:
- add busy time percent in NL80211 interface

v4:
- fix compilation error
- Take into acount current channel busy time percent

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 (4):
mac80211: use AQL airtime for expected throughput.
mac80211: add periodic monitor for channel busy time
mac80211: add busy time factor into expected throughput
mac80211: extend channel info with average busy time.

include/net/cfg80211.h | 1 +
include/uapi/linux/nl80211.h | 2 ++
net/mac80211/cfg.c | 8 +++++
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 ++++-
net/wireless/nl80211.c | 6 ++++
11 files changed, 156 insertions(+), 1 deletion(-)

--
2.37.1


2022-07-19 13:56:15

by Baligh GASMI

[permalink] [raw]
Subject: [RFC/RFT v5 3/4] mac80211: add busy time factor into expected throughput

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

Signed-off-by: Baligh Gasmi <[email protected]>
---
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..7e32c06ae771 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->deflink.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);
--
2.37.1

2022-07-19 13:56:51

by Baligh GASMI

[permalink] [raw]
Subject: [RFC/RFT v5 2/4] mac80211: add periodic monitor for channel busy time

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 <[email protected]>
---
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 15a73b7fdd75..e1b20964933c 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1972,6 +1972,64 @@ 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,
@@ -2085,6 +2143,8 @@ 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;
@@ -2156,6 +2216,9 @@ 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;

@@ -2166,6 +2229,8 @@ 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);
--
2.37.1

2022-07-19 13:56:51

by Baligh GASMI

[permalink] [raw]
Subject: [RFC/RFT v5 4/4] mac80211: extend channel info with average busy time.

Add the average busy time of the channel in the nl80211.

Signed-off-by: Baligh Gasmi <[email protected]>
---
include/net/cfg80211.h | 1 +
include/uapi/linux/nl80211.h | 2 ++
net/mac80211/cfg.c | 8 ++++++++
net/wireless/nl80211.c | 6 ++++++
4 files changed, 17 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 80f41446b1f0..38bafcaf3446 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4494,6 +4494,7 @@ struct cfg80211_ops {
struct cfg80211_fils_aad *fils_aad);
int (*set_radar_background)(struct wiphy *wiphy,
struct cfg80211_chan_def *chandef);
+ int (*get_avg_busy_time)(struct wiphy *wiphy, struct net_device *dev);
};

/*
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index d9490e3062a7..4e625f656bd6 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -3177,6 +3177,8 @@ enum nl80211_attrs {

NL80211_ATTR_DISABLE_EHT,

+ NL80211_ATTR_WIPHY_AVG_BUSY_TIME,
+
/* add attributes here, update the policy in nl80211.c */

__NL80211_ATTR_AFTER_LAST,
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 4ddf297f40f2..21a9d0b37ff5 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -4536,6 +4536,13 @@ ieee80211_set_radar_background(struct wiphy *wiphy,
return local->ops->set_radar_background(&local->hw, chandef);
}

+static int ieee80211_get_avg_busy_time(struct wiphy *wiphy,
+ struct net_device *dev)
+{
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ return ewma_avg_busy_read(&sdata->avg_busy);
+}
+
const struct cfg80211_ops mac80211_config_ops = {
.add_virtual_intf = ieee80211_add_iface,
.del_virtual_intf = ieee80211_del_iface,
@@ -4641,4 +4648,5 @@ const struct cfg80211_ops mac80211_config_ops = {
.set_sar_specs = ieee80211_set_sar_specs,
.color_change = ieee80211_color_change,
.set_radar_background = ieee80211_set_radar_background,
+ .get_avg_busy_time = ieee80211_get_avg_busy_time,
};
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 740b29481bc6..eeb3d85fd506 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3717,6 +3717,12 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flag
goto nla_put_failure;
}

+ if (rdev->ops->get_avg_busy_time) {
+ int busy = rdev->ops->get_avg_busy_time(&rdev->wiphy, dev);
+ nla_put_u32(msg, NL80211_ATTR_WIPHY_AVG_BUSY_TIME,
+ busy);
+ }
+
wdev_lock(wdev);
switch (wdev->iftype) {
case NL80211_IFTYPE_AP:
--
2.37.1

2022-08-25 08:58:35

by Johannes Berg

[permalink] [raw]
Subject: Re: [RFC/RFT v5 2/4] mac80211: add periodic monitor for channel busy time

On Tue, 2022-07-19 at 14:35 +0200, Baligh Gasmi wrote:
> 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.
>

I really don't think you should/can do this - having a 1-second periodic
timer (for each interface even!) is going to be really bad for power
consumption.

Please find a way to inline the recalculation with statistics updates
and/or queries.

johannes

2022-08-25 09:42:31

by Baligh GASMI

[permalink] [raw]
Subject: Re: [RFC/RFT v5 2/4] mac80211: add periodic monitor for channel busy time

Ok, noted !
I will try to find a way or maybe remove this part, since the busy
time is not trivial to be used in the estimation, as I thought.
Thanks for your reply.


Le jeu. 25 août 2022 à 10:58, Johannes Berg
<[email protected]> a écrit :
>
> On Tue, 2022-07-19 at 14:35 +0200, Baligh Gasmi wrote:
> > 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.
> >
>
> I really don't think you should/can do this - having a 1-second periodic
> timer (for each interface even!) is going to be really bad for power
> consumption.
>
> Please find a way to inline the recalculation with statistics updates
> and/or queries.
>
> johannes

2022-08-25 13:50:24

by Nicolas Escande

[permalink] [raw]
Subject: Re: [RFC/RFT v5 2/4] mac80211: add periodic monitor for channel busy time

On Tue Jul 19, 2022 at 2:35 PM CEST, Baligh Gasmi wrote:
> 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 <[email protected]>
> ---
> 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 15a73b7fdd75..e1b20964933c 100644
> --- a/net/mac80211/iface.c
> +++ b/net/mac80211/iface.c
> @@ -1972,6 +1972,64 @@ 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);
This could use a div_u64()
> + /* 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,
> @@ -2085,6 +2143,8 @@ 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;
> @@ -2156,6 +2216,9 @@ 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;
>
> @@ -2166,6 +2229,8 @@ 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);
> --
> 2.37.1

2022-08-25 13:55:11

by Nicolas Escande

[permalink] [raw]
Subject: Re: [RFC/RFT v5 3/4] mac80211: add busy time factor into expected throughput

On Tue Jul 19, 2022 at 2:35 PM CEST, Baligh Gasmi wrote:
> When estimating the expected throughput, take into account the busy time
> of the current channel.
>
> Signed-off-by: Baligh Gasmi <[email protected]>
> ---
> 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..7e32c06ae771 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->deflink.tx_stats.tp_tx_time_est * avg_busy) / 100;
Once again div_u64() ?
> +
> 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);
> --
> 2.37.1