[RFC] mac80211: sample survey implementation for mac80211 & hwsim

[RFC] mac80211: sample survey implementation for mac80211 & hwsim

[Holger Schurig]

This adds the survey function to both mac80211 itself and to mac80211_hwsim.
For the latter driver, we simply invent some noise level.A real driver which
cannot determine the real channel noise MUST NOT report any noise, especially
not a magically conjured one :-)

Signed-off-by: Holger Schurig <holgerschurig@gmail.com>

---
 drivers/net/wireless/mac80211_hwsim.c |   28 ++++++++++++++++++++++++++++
 include/net/mac80211.h                |    3 ++-
 net/mac80211/cfg.c                    |   12 ++++++++++++
 net/mac80211/driver-ops.h             |    9 +++++++++
 4 files changed, 51 insertions(+), 1 deletion(-)

--- linux-wl.orig/include/net/mac80211.h
+++ linux-wl/include/net/mac80211.h
@@ -1673,7 +1673,8 @@ struct ieee80211_ops {
 			    struct ieee80211_vif *vif,
 			    enum ieee80211_ampdu_mlme_action action,
 			    struct ieee80211_sta *sta, u16 tid, u16 *ssn);
-
+	int (*get_survey)(struct ieee80211_hw *hw, int idx,
+		struct survey_info *survey);
 	void (*rfkill_poll)(struct ieee80211_hw *hw);
 	void (*set_coverage_class)(struct ieee80211_hw *hw, u8 coverage_class);
 #ifdef CONFIG_NL80211_TESTMODE
--- linux-wl.orig/net/mac80211/cfg.c
+++ linux-wl/net/mac80211/cfg.c
@@ -411,6 +411,17 @@ static int ieee80211_dump_station(struct
 	return ret;
 }
 
+static int ieee80211_dump_survey(struct wiphy *wiphy, struct net_device *dev,
+				 int idx, struct survey_info *survey)
+{
+	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+
+	if (!local->ops->get_survey)
+		return -EOPNOTSUPP;
+
+	return drv_get_survey(local, idx, survey);
+}
+
 static int ieee80211_get_station(struct wiphy *wiphy, struct net_device *dev,
 				 u8 *mac, struct station_info *sinfo)
 {
@@ -1508,6 +1519,7 @@ struct cfg80211_ops mac80211_config_ops
 	.change_station = ieee80211_change_station,
 	.get_station = ieee80211_get_station,
 	.dump_station = ieee80211_dump_station,
+	.dump_survey = ieee80211_dump_survey,
 #ifdef CONFIG_MAC80211_MESH
 	.add_mpath = ieee80211_add_mpath,
 	.del_mpath = ieee80211_del_mpath,
--- linux-wl.orig/net/mac80211/driver-ops.h
+++ linux-wl/net/mac80211/driver-ops.h
@@ -346,6 +346,15 @@ static inline int drv_ampdu_action(struc
 	return ret;
 }
 
+static inline int drv_get_survey(struct ieee80211_local *local, int idx,
+				struct survey_info *survey)
+{
+	int ret = -EOPNOTSUPP;
+	if (local->ops->conf_tx)
+		ret = local->ops->get_survey(&local->hw, idx, survey);
+	/* trace_drv_get_survey(local, idx, survey, ret); */
+	return ret;
+}
 
 static inline void drv_rfkill_poll(struct ieee80211_local *local)
 {
--- linux-wl.orig/drivers/net/wireless/mac80211_hwsim.c
+++ linux-wl/drivers/net/wireless/mac80211_hwsim.c
@@ -830,6 +830,33 @@ static int mac80211_hwsim_conf_tx(
 	return 0;
 }
 
+static int mac80211_hwsim_get_survey(
+	struct ieee80211_hw *hw, int idx,
+	struct survey_info *survey)
+{
+	struct ieee80211_conf *conf = &hw->conf;
+
+	printk(KERN_DEBUG "%s:%s (idx=%d)\n",
+	       wiphy_name(hw->wiphy), __func__, idx);
+
+	if (idx != 0)
+		return -ENOENT;
+
+	/* Current channel */
+	survey->channel = conf->channel;
+
+	/*
+	 * Magically conjured noise level --- this is only ok for simulated hardware.
+	 *
+	 * A real driver which cannot determine the real channel noise MUST NOT
+	 * report any noise, especially not a magically conjured one :-)
+	 */
+	survey->filled = SURVEY_INFO_NOISE_DBM;
+	survey->noise = -92;
+
+	return 0;
+}
+
 #ifdef CONFIG_NL80211_TESTMODE
 /*
  * This section contains example code for using netlink
@@ -1013,6 +1040,7 @@ static struct ieee80211_ops mac80211_hws
 	.sta_notify = mac80211_hwsim_sta_notify,
 	.set_tim = mac80211_hwsim_set_tim,
 	.conf_tx = mac80211_hwsim_conf_tx,
+	.get_survey = mac80211_hwsim_get_survey,
 	CFG80211_TESTMODE_CMD(mac80211_hwsim_testmode_cmd)
 	.ampdu_action = mac80211_hwsim_ampdu_action,
 	.sw_scan_start = mac80211_hwsim_sw_scan,

-- 
DH3HS, http://www.holgerschurig.de

Re: [RFC] mac80211: sample survey implementation for mac80211 & hwsim

[Holger Schurig]

Oh, that should have been [PATCH].

So much to copying subject lines from quilt patches without really reading.


-- 
DH3HS, http://www.holgerschurig.de

Re: [RFC] mac80211: sample survey implementation for mac80211 & hwsim

[Johannes Berg]

How does this work with multiple channels? And how about knowing how old
the info is?

> +static inline int drv_get_survey(struct ieee80211_local *local, int idx,
> +				struct survey_info *survey)
> +{
> +	int ret = -EOPNOTSUPP;
> +	if (local->ops->conf_tx)
> +		ret = local->ops->get_survey(&local->hw, idx, survey);
> +	/* trace_drv_get_survey(local, idx, survey, ret); */

Lazy huh? :)

johannes

Re: [RFC] mac80211: sample survey implementation for mac80211 & hwsim

[Joerg Pommnitz]

Holger Schurig <holgerschurig@...> writes:

> 
> +static int ieee80211_dump_survey(struct wiphy *wiphy, struct net_device *dev,
> +				 int idx, struct survey_info *survey)
> +{
> +	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
> +
> +	if (!local->ops->get_survey)
> +		return -EOPNOTSUPP;

The check for the function is duplicated in drv_get_survey. I think the
wrapper should be called unconditionally.

> +
> +	return drv_get_survey(local, idx, survey);
> +}
> +

Re: [RFC] mac80211: sample survey implementation for mac80211 & hwsim

[Johannes Berg]

Holger,

> > +static int ieee80211_dump_survey(struct wiphy *wiphy, struct net_device *dev,
> > +				 int idx, struct survey_info *survey)
> > +{
> > +	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
> > +
> > +	if (!local->ops->get_survey)
> > +		return -EOPNOTSUPP;
> 
> The check for the function is duplicated in drv_get_survey. I think the
> wrapper should be called unconditionally.

Please address this comment and add tracing. Your patch was merged, so
that needs to be an add-on patch.

johannes

[PATCH] mac80211: remove unnecessary check in ieee80211_dump_survey

[John W. Linville]

This check is duplicated in drv_get_survey.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
 net/mac80211/cfg.c |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index f4efbfa..e55970b 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -413,9 +413,6 @@ static int ieee80211_dump_survey(struct wiphy *wiphy, struct net_device *dev,
 {
 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 
-	if (!local->ops->get_survey)
-		return -EOPNOTSUPP;
-
 	return drv_get_survey(local, idx, survey);
 }
 
-- 
1.7.0.1

[PATCH] mac80211: add basic tracing to drv_get_survey

[John W. Linville]

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
 net/mac80211/driver-ops.h   |    7 ++++++-
 net/mac80211/driver-trace.h |   22 ++++++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletions(-)

diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index c333173..14123dc 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -375,9 +375,14 @@ static inline int drv_get_survey(struct ieee80211_local *local, int idx,
 				struct survey_info *survey)
 {
 	int ret = -EOPNOTSUPP;
+
+	trace_drv_get_survey(local, idx, survey);
+
 	if (local->ops->get_survey)
 		ret = local->ops->get_survey(&local->hw, idx, survey);
-	/* trace_drv_get_survey(local, idx, survey, ret); */
+
+	trace_drv_return_int(local, ret);
+
 	return ret;
 }
 
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index 8da31ca..5d5d2a9 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -761,6 +761,28 @@ TRACE_EVENT(drv_ampdu_action,
 	)
 );
 
+TRACE_EVENT(drv_get_survey,
+	TP_PROTO(struct ieee80211_local *local, int idx,
+		 struct survey_info *survey),
+
+	TP_ARGS(local, idx, survey),
+
+	TP_STRUCT__entry(
+		LOCAL_ENTRY
+		__field(int, idx)
+	),
+
+	TP_fast_assign(
+		LOCAL_ASSIGN;
+		__entry->idx = idx;
+	),
+
+	TP_printk(
+		LOCAL_PR_FMT " idx:%d",
+		LOCAL_PR_ARG, __entry->idx
+	)
+);
+
 TRACE_EVENT(drv_flush,
 	TP_PROTO(struct ieee80211_local *local, bool drop),
 
-- 
1.7.0.1