cfg80211: Expose TXQ stats and parameters to userspace

This adds support for exporting the mac80211 TXQ stats via nl80211 by
way of a nested TXQ stats attribute, as well as for configuring the
quantum and limits that were previously only changeable through debugfs.

This commit adds just the nl80211 API, a subsequent commit adds support to
mac80211 itself.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -1079,6 +1079,37 @@ struct sta_bss_parameters {
 	u16 beacon_interval;
 };
 
+/**
+ * struct cfg80211_txq_stats - TXQ statistics for this TID
+ * @filled: bitmap of flags using the bits of &enum nl80211_txq_stats to
+ *	indicate the relevant values in this struct are filled
+ * @backlog_bytes: total number of bytes currently backlogged
+ * @backlog_packets: total number of packets currently backlogged
+ * @flows: number of new flows seen
+ * @drops: total number of packets dropped
+ * @ecn_marks: total number of packets marked with ECN CE
+ * @overlimit: number of drops due to queue space overflow
+ * @overmemory: number of drops due to memory limit overflow
+ * @collisions: number of hash collisions
+ * @tx_bytes: total number of bytes dequeued
+ * @tx_packets: total number of packets dequeued
+ * @max_flows: maximum number of flows supported
+ */
+struct cfg80211_txq_stats {
+	u32 filled;
+	u32 backlog_bytes;
+	u32 backlog_packets;
+	u32 flows;
+	u32 drops;
+	u32 ecn_marks;
+	u32 overlimit;
+	u32 overmemory;
+	u32 collisions;
+	u32 tx_bytes;
+	u32 tx_packets;
+	u32 max_flows;
+};
+
 /**
  * struct cfg80211_tid_stats - per-TID statistics
  * @filled: bitmap of flags using the bits of &enum nl80211_tid_stats to
@@ -1088,6 +1119,7 @@ struct sta_bss_parameters {
  * @tx_msdu_retries: number of retries (not counting the first) for
  *	transmitted MSDUs
  * @tx_msdu_failed: number of failed transmitted MSDUs
+ * @txq_stats: TXQ statistics
  */
 struct cfg80211_tid_stats {
 	u32 filled;
@@ -1095,6 +1127,7 @@ struct cfg80211_tid_stats {
 	u64 tx_msdu;
 	u64 tx_msdu_retries;
 	u64 tx_msdu_failed;
+	struct cfg80211_txq_stats txq_stats;
 };
 
 #define IEEE80211_MAX_CHAINS	4
@@ -2204,6 +2237,9 @@ enum cfg80211_connect_params_changed {
  * @WIPHY_PARAM_RTS_THRESHOLD: wiphy->rts_threshold has changed
  * @WIPHY_PARAM_COVERAGE_CLASS: coverage class changed
  * @WIPHY_PARAM_DYN_ACK: dynack has been enabled
+ * @WIPHY_PARAM_TXQ_LIMIT: TXQ packet limit has been changed
+ * @WIPHY_PARAM_TXQ_MEMORY_LIMIT: TXQ memory limit has been changed
+ * @WIPHY_PARAM_TXQ_QUANTUM: TXQ scheduler quantum
  */
 enum wiphy_params_flags {
 	WIPHY_PARAM_RETRY_SHORT		= 1 << 0,
@@ -2212,6 +2248,9 @@ enum wiphy_params_flags {
 	WIPHY_PARAM_RTS_THRESHOLD	= 1 << 3,
 	WIPHY_PARAM_COVERAGE_CLASS	= 1 << 4,
 	WIPHY_PARAM_DYN_ACK		= 1 << 5,
+	WIPHY_PARAM_TXQ_LIMIT		= 1 << 6,
+	WIPHY_PARAM_TXQ_MEMORY_LIMIT	= 1 << 7,
+	WIPHY_PARAM_TXQ_QUANTUM		= 1 << 8,
 };
 
 /**
@@ -2964,6 +3003,9 @@ struct cfg80211_external_auth_params {
  *
  * @set_multicast_to_unicast: configure multicast to unicast conversion for BSS
  *
+ * @get_txq_stats: Get TXQ stats for interface or phy. If wdev is %NULL, this
+ *      function should return phy stats, and interface stats otherwise.
+ *
  * @set_pmk: configure the PMK to be used for offloaded 802.1X 4-Way handshake.
  *	If not deleted through @del_pmk the PMK remains valid until disconnect
  *	upon which the driver should clear it.
@@ -3265,6 +3307,10 @@ struct cfg80211_ops {
 					    struct net_device *dev,
 					    const bool enabled);
 
+	int	(*get_txq_stats)(struct wiphy *wiphy,
+				 struct wireless_dev *wdev,
+				 struct cfg80211_txq_stats *txqstats);
+
 	int	(*set_pmk)(struct wiphy *wiphy, struct net_device *dev,
 			   const struct cfg80211_pmk_conf *conf);
 	int	(*del_pmk)(struct wiphy *wiphy, struct net_device *dev,
@@ -3943,6 +3989,10 @@ struct wiphy {
 
 	u8 nan_supported_bands;
 
+	u32 txq_limit;
+	u32 txq_memory_limit;
+	u32 txq_quantum;
+
 	char priv[0] __aligned(NETDEV_ALIGN);
 };
 

include/uapi/linux/nl80211.h

@@ -2226,6 +2226,16 @@ enum nl80211_commands {
  * @NL80211_ATTR_NSS: Station's New/updated  RX_NSS value notified using this
  *	u8 attribute. This is used with %NL80211_CMD_STA_OPMODE_CHANGED.
  *
+ * @NL80211_ATTR_TXQ_STATS: TXQ statistics (nested attribute, see &enum
+ *      nl80211_txq_stats)
+ * @NL80211_ATTR_TXQ_LIMIT: Total packet limit for the TXQ queues for this phy.
+ *      The smaller of this and the memory limit is enforced.
+ * @NL80211_ATTR_TXQ_MEMORY_LIMIT: Total memory memory limit (in bytes) for the
+ *      TXQ queues for this phy. The smaller of this and the packet limit is
+ *      enforced.
+ * @NL80211_ATTR_TXQ_QUANTUM: TXQ scheduler quantum (bytes). Number of bytes
+ *      a flow is assigned on each round of the DRR scheduler.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2660,6 +2670,11 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_CONTROL_PORT_OVER_NL80211,
 
+	NL80211_ATTR_TXQ_STATS,
+	NL80211_ATTR_TXQ_LIMIT,
+	NL80211_ATTR_TXQ_MEMORY_LIMIT,
+	NL80211_ATTR_TXQ_QUANTUM,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -3040,6 +3055,7 @@ enum nl80211_sta_info {
  * @NL80211_TID_STATS_TX_MSDU_FAILED: number of failed transmitted
  *	MSDUs (u64)
  * @NL80211_TID_STATS_PAD: attribute used for padding for 64-bit alignment
+ * @NL80211_TID_STATS_TXQ_STATS: TXQ stats (nested attribute)
  * @NUM_NL80211_TID_STATS: number of attributes here
  * @NL80211_TID_STATS_MAX: highest numbered attribute here
  */
@@ -3050,12 +3066,51 @@ enum nl80211_tid_stats {
 	NL80211_TID_STATS_TX_MSDU_RETRIES,
 	NL80211_TID_STATS_TX_MSDU_FAILED,
 	NL80211_TID_STATS_PAD,
+	NL80211_TID_STATS_TXQ_STATS,
 
 	/* keep last */
 	NUM_NL80211_TID_STATS,
 	NL80211_TID_STATS_MAX = NUM_NL80211_TID_STATS - 1
 };
 
+/**
+ * enum nl80211_txq_stats - per TXQ statistics attributes
+ * @__NL80211_TXQ_STATS_INVALID: attribute number 0 is reserved
+ * @NUM_NL80211_TXQ_STATS: number of attributes here
+ * @NL80211_TXQ_STATS_BACKLOG_BYTES: number of bytes currently backlogged
+ * @NL80211_TXQ_STATS_BACKLOG_PACKETS: number of packets currently
+ *      backlogged
+ * @NL80211_TXQ_STATS_FLOWS: total number of new flows seen
+ * @NL80211_TXQ_STATS_DROPS: total number of packet drops
+ * @NL80211_TXQ_STATS_ECN_MARKS: total number of packet ECN marks
+ * @NL80211_TXQ_STATS_OVERLIMIT: number of drops due to queue space overflow
+ * @NL80211_TXQ_STATS_OVERMEMORY: number of drops due to memory limit overflow
+ *      (only for per-phy stats)
+ * @NL80211_TXQ_STATS_COLLISIONS: number of hash collisions
+ * @NL80211_TXQ_STATS_TX_BYTES: total number of bytes dequeued from TXQ
+ * @NL80211_TXQ_STATS_TX_PACKETS: total number of packets dequeued from TXQ
+ * @NL80211_TXQ_STATS_MAX_FLOWS: number of flow buckets for PHY
+ * @NL80211_TXQ_STATS_MAX: highest numbered attribute here
+ */
+enum nl80211_txq_stats {
+	__NL80211_TXQ_STATS_INVALID,
+	NL80211_TXQ_STATS_BACKLOG_BYTES,
+	NL80211_TXQ_STATS_BACKLOG_PACKETS,
+	NL80211_TXQ_STATS_FLOWS,
+	NL80211_TXQ_STATS_DROPS,
+	NL80211_TXQ_STATS_ECN_MARKS,
+	NL80211_TXQ_STATS_OVERLIMIT,
+	NL80211_TXQ_STATS_OVERMEMORY,
+	NL80211_TXQ_STATS_COLLISIONS,
+	NL80211_TXQ_STATS_TX_BYTES,
+	NL80211_TXQ_STATS_TX_PACKETS,
+	NL80211_TXQ_STATS_MAX_FLOWS,
+
+	/* keep last */
+	NUM_NL80211_TXQ_STATS,
+	NL80211_TXQ_STATS_MAX = NUM_NL80211_TXQ_STATS - 1
+};
+
 /**
  * enum nl80211_mpath_flags - nl80211 mesh path flags
  *
@@ -5072,6 +5127,8 @@ enum nl80211_feature_flags {
  * @NL80211_EXT_FEATURE_DATA_ACK_SIGNAL_SUPPORT: This Driver support data ack
  *	rssi if firmware support, this flag is to intimate about ack rssi
  *	support to nl80211.
+ * @NL80211_EXT_FEATURE_TXQS: Driver supports FQ-CoDel-enabled intermediate
+ *      TXQs.
  *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
@@ -5105,6 +5162,7 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_DFS_OFFLOAD,
 	NL80211_EXT_FEATURE_CONTROL_PORT_OVER_NL80211,
 	NL80211_EXT_FEATURE_DATA_ACK_SIGNAL_SUPPORT,
+	NL80211_EXT_FEATURE_TXQS,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,

net/mac80211/ethtool.c

@@ -71,11 +71,15 @@ static void ieee80211_get_stats(struct net_device *dev,
 	struct ieee80211_channel *channel;
 	struct sta_info *sta;
 	struct ieee80211_local *local = sdata->local;
-	struct station_info sinfo;
+	struct station_info *sinfo;
 	struct survey_info survey;
 	int i, q;
 #define STA_STATS_SURVEY_LEN 7
 
+	sinfo = kmalloc(sizeof(*sinfo), GFP_KERNEL);
+	if (!sinfo)
+		return;
+
 	memset(data, 0, sizeof(u64) * STA_STATS_LEN);
 
 #define ADD_STA_STATS(sta)					\
@@ -86,8 +90,8 @@ static void ieee80211_get_stats(struct net_device *dev,
 		data[i++] += sta->rx_stats.fragments;		\
 		data[i++] += sta->rx_stats.dropped;		\
 								\
-		data[i++] += sinfo.tx_packets;			\
-		data[i++] += sinfo.tx_bytes;			\
+		data[i++] += sinfo->tx_packets;			\
+		data[i++] += sinfo->tx_bytes;			\
 		data[i++] += sta->status_stats.filtered;	\
 		data[i++] += sta->status_stats.retry_failed;	\
 		data[i++] += sta->status_stats.retry_count;	\
@@ -107,8 +111,8 @@ static void ieee80211_get_stats(struct net_device *dev,
 		if (!(sta && !WARN_ON(sta->sdata->dev != dev)))
 			goto do_survey;
 
-		memset(&sinfo, 0, sizeof(sinfo));
-		sta_set_sinfo(sta, &sinfo);
+		memset(sinfo, 0, sizeof(*sinfo));
+		sta_set_sinfo(sta, sinfo);
 
 		i = 0;
 		ADD_STA_STATS(sta);
@@ -116,17 +120,17 @@ static void ieee80211_get_stats(struct net_device *dev,
 		data[i++] = sta->sta_state;
 
 
-		if (sinfo.filled & BIT(NL80211_STA_INFO_TX_BITRATE))
+		if (sinfo->filled & BIT(NL80211_STA_INFO_TX_BITRATE))
 			data[i] = 100000 *
-				cfg80211_calculate_bitrate(&sinfo.txrate);
+				cfg80211_calculate_bitrate(&sinfo->txrate);
 		i++;
-		if (sinfo.filled & BIT(NL80211_STA_INFO_RX_BITRATE))
+		if (sinfo->filled & BIT(NL80211_STA_INFO_RX_BITRATE))
 			data[i] = 100000 *
-				cfg80211_calculate_bitrate(&sinfo.rxrate);
+				cfg80211_calculate_bitrate(&sinfo->rxrate);
 		i++;
 
-		if (sinfo.filled & BIT(NL80211_STA_INFO_SIGNAL_AVG))
-			data[i] = (u8)sinfo.signal_avg;
+		if (sinfo->filled & BIT(NL80211_STA_INFO_SIGNAL_AVG))
+			data[i] = (u8)sinfo->signal_avg;
 		i++;
 	} else {
 		list_for_each_entry(sta, &local->sta_list, list) {
@@ -134,14 +138,16 @@ static void ieee80211_get_stats(struct net_device *dev,
 			if (sta->sdata->dev != dev)
 				continue;
 
-			memset(&sinfo, 0, sizeof(sinfo));
-			sta_set_sinfo(sta, &sinfo);
+			memset(sinfo, 0, sizeof(*sinfo));
+			sta_set_sinfo(sta, sinfo);
 			i = 0;
 			ADD_STA_STATS(sta);
 		}
 	}
 
 do_survey:
+	kfree(sinfo);
+
 	i = STA_STATS_LEN - STA_STATS_SURVEY_LEN;
 	/* Get survey stats for current channel */
 	survey.filled = 0;

net/wireless/rdev-ops.h

@@ -586,6 +586,18 @@ rdev_set_multicast_to_unicast(struct cfg80211_registered_device *rdev,
 	return ret;
 }
 
+static inline int
+rdev_get_txq_stats(struct cfg80211_registered_device *rdev,
+		   struct wireless_dev *wdev,
+		   struct cfg80211_txq_stats *txqstats)
+{
+	int ret;
+	trace_rdev_get_txq_stats(&rdev->wiphy, wdev);
+	ret = rdev->ops->get_txq_stats(&rdev->wiphy, wdev, txqstats);
+	trace_rdev_return_int(&rdev->wiphy, ret);
+	return ret;
+}
+
 static inline void rdev_rfkill_poll(struct cfg80211_registered_device *rdev)
 {
 	trace_rdev_rfkill_poll(&rdev->wiphy);

net/wireless/trace.h

@@ -3243,6 +3243,20 @@ TRACE_EVENT(rdev_set_multicast_to_unicast,
 		  WIPHY_PR_ARG, NETDEV_PR_ARG,
 		  BOOL_TO_STR(__entry->enabled))
 );
+
+TRACE_EVENT(rdev_get_txq_stats,
+	TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev),
+	TP_ARGS(wiphy, wdev),
+	TP_STRUCT__entry(
+		WIPHY_ENTRY
+		WDEV_ENTRY
+	),
+	TP_fast_assign(
+		WIPHY_ASSIGN;
+		WDEV_ASSIGN;
+	),
+	TP_printk(WIPHY_PR_FMT ", " WDEV_PR_FMT, WIPHY_PR_ARG, WDEV_PR_ARG)
+);
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH

net/wireless/wext-compat.c

@@ -1254,7 +1254,7 @@ static int cfg80211_wext_giwrate(struct net_device *dev,
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
-	struct station_info sinfo = {};
+	struct station_info *sinfo;
 	u8 addr[ETH_ALEN];
 	int err;
 
@@ -1274,16 +1274,23 @@ static int cfg80211_wext_giwrate(struct net_device *dev,
 	if (err)
 		return err;
 
-	err = rdev_get_station(rdev, dev, addr, &sinfo);
-	if (err)
-		return err;
+	sinfo = kzalloc(sizeof(*sinfo), GFP_KERNEL);
+	if (!sinfo)
+		return -ENOMEM;
 
-	if (!(sinfo.filled & BIT(NL80211_STA_INFO_TX_BITRATE)))
-		return -EOPNOTSUPP;
+	err = rdev_get_station(rdev, dev, addr, sinfo);
+	if (err)
+		goto out;
 
-	rate->value = 100000 * cfg80211_calculate_bitrate(&sinfo.txrate);
+	if (!(sinfo->filled & BIT(NL80211_STA_INFO_TX_BITRATE))) {
+		err = -EOPNOTSUPP;
+		goto out;
+	}
 
-	return 0;
+	rate->value = 100000 * cfg80211_calculate_bitrate(&sinfo->txrate);
+out:
+	kfree(sinfo);
+	return err;
 }
 
 /* Get wireless statistics.  Called by /proc/net/wireless and by SIOCGIWSTATS */