[RFC PATCHv4 0/2] mac80211: cfg80211: dynamic ps timeout based on pm-qos

[RFC PATCHv4 0/2] mac80211: cfg80211: dynamic ps timeout based on pm-qos

[Juuso Oikarinen]

These patches propose a way to adjust the dynamic ps timeout in the mac80211
based on the pm-qos network latency value. This allows user space to influence
the level of power saving performed by the mac80211.

v4 of these patches change the way pm qos network latency ranges converted to 
dynamic ps timeout values a little bit saner. Unlike the previous set of
patches, now the latancy values make sense in a wider scope than this 
ps timeout thing only. I hope this makes them somewhat more future-proof.

As wext still has an interface to adjust the dynamic ps timeout from userspace,
the wext configuration will override the above, to remain backwards
compatible.

Comments are appreciated.

Juuso Oikarinen (2):
  mac80211: Determine dynamic PS timeout based on ps-qos network
    latency
  cfg80211: Remove default dynamic PS timeout value

 include/net/cfg80211.h |    2 ++
 include/net/mac80211.h |    5 ++++-
 net/mac80211/cfg.c     |    4 ++--
 net/mac80211/main.c    |    2 ++
 net/mac80211/mlme.c    |   21 +++++++++++++++++++++
 net/wireless/core.c    |    3 ++-
 6 files changed, 33 insertions(+), 4 deletions(-)

[RFC PATCHv4 1/2] mac80211: Determine dynamic PS timeout based on ps-qos network latency

[Juuso Oikarinen]

Determine the dynamic PS timeout based on the configured ps-qos network
latency. For backwards wext compatibility, allow the dynamic PS timeout
configured by the cfg80211 to overrule the automatically determined value.

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
---
 include/net/mac80211.h |    5 ++++-
 net/mac80211/cfg.c     |    4 ++--
 net/mac80211/main.c    |    2 ++
 net/mac80211/mlme.c    |   21 +++++++++++++++++++++
 4 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index dcf3c5f..243e4ab 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -661,6 +661,9 @@ enum ieee80211_smps_mode {
  * @dynamic_ps_timeout: The dynamic powersave timeout (in ms), see the
  *	powersave documentation below. This variable is valid only when
  *	the CONF_PS flag is set.
+ * @dynamic_ps_forced_timeout: The dynamic powersave timeout (in ms) configured
+ *	by cfg80211 (essentially, wext) If set, this value overrules the value
+ *	chosen by mac80211 based on ps qos network latency.
  *
  * @power_level: requested transmit power (in dBm)
  *
@@ -680,7 +683,7 @@ enum ieee80211_smps_mode {
  */
 struct ieee80211_conf {
 	u32 flags;
-	int power_level, dynamic_ps_timeout;
+	int power_level, dynamic_ps_timeout, dynamic_ps_forced_timeout;
 	int max_sleep_period;
 
 	u16 listen_interval;
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 7dd7cda..9a1a91c 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1388,11 +1388,11 @@ static int ieee80211_set_power_mgmt(struct wiphy *wiphy, struct net_device *dev,
 		return -EOPNOTSUPP;
 
 	if (enabled == sdata->u.mgd.powersave &&
-	    timeout == conf->dynamic_ps_timeout)
+	    timeout == conf->dynamic_ps_forced_timeout)
 		return 0;
 
 	sdata->u.mgd.powersave = enabled;
-	conf->dynamic_ps_timeout = timeout;
+	conf->dynamic_ps_forced_timeout = timeout;
 
 	/* no change, but if automatic follow powersave */
 	mutex_lock(&sdata->u.mgd.mtx);
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 4afe851..ebcca0e 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -569,6 +569,8 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 
 	local->hw.conf.listen_interval = local->hw.max_listen_interval;
 
+	local->hw.conf.dynamic_ps_forced_timeout = -1;
+
 	result = sta_info_start(local);
 	if (result < 0)
 		goto fail_sta_info;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 35d8502..7e6d0ab 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -476,6 +476,7 @@ void ieee80211_recalc_ps(struct ieee80211_local *local, s32 latency)
 {
 	struct ieee80211_sub_if_data *sdata, *found = NULL;
 	int count = 0;
+	int timeout;
 
 	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS)) {
 		local->ps_sdata = NULL;
@@ -509,6 +510,26 @@ void ieee80211_recalc_ps(struct ieee80211_local *local, s32 latency)
 		beaconint_us = ieee80211_tu_to_usec(
 					found->vif.bss_conf.beacon_int);
 
+		timeout = local->hw.conf.dynamic_ps_forced_timeout;
+		if (timeout < 0) {
+			/*
+			 * The 2 second value is there for compatibility until
+			 * the PM_QOS_NETWORK_LATENCY is configured with real
+			 * values.
+			 */
+			if (latency == 2000000000)
+				timeout = 100;
+			else if (latency <= 50000)
+				timeout = 300;
+			else if (latency <= 100000)
+				timeout = 100;
+			else if (latency <= 500000)
+				timeout = 50;
+			else
+				timeout = 0;
+		}
+		local->hw.conf.dynamic_ps_timeout = timeout;
+
 		if (beaconint_us > latency) {
 			local->ps_sdata = NULL;
 		} else {
-- 
1.6.3.3

[RFC PATCHv4 2/2] cfg80211: Remove default dynamic PS timeout value

[Juuso Oikarinen]

Now that the mac80211 is choosing dynamic ps timeouts based on the ps-qos
network latency configuration, configure a default value of -1 as the dynamic
ps timeout in cfg80211. This value allows the mac80211 to determine the value
to be used.

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
---
 include/net/cfg80211.h |    2 ++
 net/wireless/core.c    |    3 ++-
 2 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 37cebd3..873edf9 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1018,6 +1018,8 @@ struct cfg80211_pmksa {
  *	RSN IE. It allows for faster roaming between WPA2 BSSIDs.
  * @del_pmksa: Delete a cached PMKID.
  * @flush_pmksa: Flush all cached PMKIDs.
+ * @set_power_mgmt: Configure WLAN power management. A timeout value of -1
+ *	allows the driver to adjust the dynamic ps timeout value.
  * @set_cqm_rssi_config: Configure connection quality monitor RSSI threshold.
  *
  */
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 6ac70c1..37d0e0a 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -705,7 +705,8 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
 			wdev->ps = true;
 		else
 			wdev->ps = false;
-		wdev->ps_timeout = 100;
+		/* allow mac80211 to determine the timeout */
+		wdev->ps_timeout = -1;
 		if (rdev->ops->set_power_mgmt)
 			if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
 						      wdev->ps,
-- 
1.6.3.3

Re: [RFC PATCHv4 0/2] mac80211: cfg80211: dynamic ps timeout based on pm-qos

[Kalle Valo]

Juuso Oikarinen <juuso.oikarinen@nokia.com> writes:

> These patches propose a way to adjust the dynamic ps timeout in the
> mac80211 based on the pm-qos network latency value. This allows user
> space to influence the level of power saving performed by the
> mac80211.
>
> v4 of these patches change the way pm qos network latency ranges
> converted to dynamic ps timeout values a little bit saner. Unlike
> the previous set of patches, now the latancy values make sense in a
> wider scope than this ps timeout thing only. I hope this makes them
> somewhat more future-proof.

This looks very good now. Bonus points for adding the comment about
the two second value!

Thank you for implementing this.

-- 
Kalle Valo

Re: [RFC PATCHv4 0/2] mac80211: cfg80211: dynamic ps timeout based on pm-qos

[Luis R. Rodriguez]

On Thu, Apr 29, 2010 at 6:45 AM, Kalle Valo <kvalo@adurom.com> wrote:
> Juuso Oikarinen <juuso.oikarinen@nokia.com> writes:
>
>> These patches propose a way to adjust the dynamic ps timeout in the
>> mac80211 based on the pm-qos network latency value. This allows user
>> space to influence the level of power saving performed by the
>> mac80211.
>>
>> v4 of these patches change the way pm qos network latency ranges
>> converted to dynamic ps timeout values a little bit saner. Unlike
>> the previous set of patches, now the latancy values make sense in a
>> wider scope than this ps timeout thing only. I hope this makes them
>> somewhat more future-proof.
>
> This looks very good now. Bonus points for adding the comment about
> the two second value!
>
> Thank you for implementing this.

Even more bonus points (if this was a video game you'd get an extra
life) if you add the new changes on the documentation here:

http://wireless.kernel.org/en/developers/Documentation/pm-qos

  Luis

Re: [RFC PATCHv4 0/2] mac80211: cfg80211: dynamic ps timeout based on pm-qos

[Juuso Oikarinen]

On Tue, 2010-05-04 at 00:44 +0200, ext Luis R. Rodriguez wrote:
> On Thu, Apr 29, 2010 at 6:45 AM, Kalle Valo <kvalo@adurom.com> wrote:
> > Juuso Oikarinen <juuso.oikarinen@nokia.com> writes:
> >
> >> These patches propose a way to adjust the dynamic ps timeout in the
> >> mac80211 based on the pm-qos network latency value. This allows user
> >> space to influence the level of power saving performed by the
> >> mac80211.
> >>
> >> v4 of these patches change the way pm qos network latency ranges
> >> converted to dynamic ps timeout values a little bit saner. Unlike
> >> the previous set of patches, now the latancy values make sense in a
> >> wider scope than this ps timeout thing only. I hope this makes them
> >> somewhat more future-proof.
> >
> > This looks very good now. Bonus points for adding the comment about
> > the two second value!
> >
> > Thank you for implementing this.
> 
> Even more bonus points (if this was a video game you'd get an extra
> life) if you add the new changes on the documentation here:
> 
> http://wireless.kernel.org/en/developers/Documentation/pm-qos
> 

Can't resist a new life! Yes, I will add the changes. Honestly, I was
planning to, and almost remembered ;)

-Juuso

>   Luis