Revert "mac80211: Add TXQ scheduling API"

This reverts commit e937b8da.

Turns out that a new driver (mt76) is coming in through
Kalle's tree, and will conflict with this. It also has some
conflicting requirements, so we'll revisit this later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/ath/ath10k/core.c

@@ -2574,7 +2574,9 @@ struct ath10k *ath10k_core_create(size_t priv_size, struct device *dev,
 
 	mutex_init(&ar->conf_mutex);
 	spin_lock_init(&ar->data_lock);
+	spin_lock_init(&ar->txqs_lock);
 
+	INIT_LIST_HEAD(&ar->txqs);
 	INIT_LIST_HEAD(&ar->peers);
 	init_waitqueue_head(&ar->peer_mapping_wq);
 	init_waitqueue_head(&ar->htt.empty_tx_wq);

drivers/net/wireless/ath/ath10k/core.h

@@ -347,6 +347,7 @@ struct ath10k_peer {
 };
 
 struct ath10k_txq {
+	struct list_head list;
 	unsigned long num_fw_queued;
 	unsigned long num_push_allowed;
 };
@@ -894,7 +895,10 @@ struct ath10k {
 
 	/* protects shared structure data */
 	spinlock_t data_lock;
+	/* protects: ar->txqs, artxq->list */
+	spinlock_t txqs_lock;
 
+	struct list_head txqs;
 	struct list_head arvifs;
 	struct list_head peers;
 	struct ath10k_peer *peer_map[ATH10K_MAX_NUM_PEER_IDS];

drivers/net/wireless/ath/ath10k/mac.c

@@ -3830,10 +3830,12 @@ static void ath10k_mac_txq_init(struct ieee80211_txq *txq)
 		return;
 
 	artxq = (void *)txq->drv_priv;
+	INIT_LIST_HEAD(&artxq->list);
 }
 
 static void ath10k_mac_txq_unref(struct ath10k *ar, struct ieee80211_txq *txq)
 {
+	struct ath10k_txq *artxq;
 	struct ath10k_skb_cb *cb;
 	struct sk_buff *msdu;
 	int msdu_id;
@@ -3841,6 +3843,12 @@ static void ath10k_mac_txq_unref(struct ath10k *ar, struct ieee80211_txq *txq)
 	if (!txq)
 		return;
 
+	artxq = (void *)txq->drv_priv;
+	spin_lock_bh(&ar->txqs_lock);
+	if (!list_empty(&artxq->list))
+		list_del_init(&artxq->list);
+	spin_unlock_bh(&ar->txqs_lock);
+
 	spin_lock_bh(&ar->htt.tx_lock);
 	idr_for_each_entry(&ar->htt.pending_tx, msdu, msdu_id) {
 		cb = ATH10K_SKB_CB(msdu);
@@ -3970,17 +3978,23 @@ int ath10k_mac_tx_push_txq(struct ieee80211_hw *hw,
 void ath10k_mac_tx_push_pending(struct ath10k *ar)
 {
 	struct ieee80211_hw *hw = ar->hw;
-	struct ieee80211_txq *txq, *first = NULL;
+	struct ieee80211_txq *txq;
+	struct ath10k_txq *artxq;
+	struct ath10k_txq *last;
 	int ret;
 	int max;
 
 	if (ar->htt.num_pending_tx >= (ar->htt.max_num_pending_tx / 2))
 		return;
 
+	spin_lock_bh(&ar->txqs_lock);
 	rcu_read_lock();
 
-	txq = ieee80211_next_txq(hw);
-	while (txq) {
+	last = list_last_entry(&ar->txqs, struct ath10k_txq, list);
+	while (!list_empty(&ar->txqs)) {
+		artxq = list_first_entry(&ar->txqs, struct ath10k_txq, list);
+		txq = container_of((void *)artxq, struct ieee80211_txq,
+				   drv_priv);
 
 		/* Prevent aggressive sta/tid taking over tx queue */
 		max = 16;
@@ -3991,21 +4005,18 @@ void ath10k_mac_tx_push_pending(struct ath10k *ar)
 				break;
 		}
 
+		list_del_init(&artxq->list);
 		if (ret != -ENOENT)
-			ieee80211_schedule_txq(hw, txq);
+			list_add_tail(&artxq->list, &ar->txqs);
 
 		ath10k_htt_tx_txq_update(hw, txq);
 
-		if (first == txq || (ret < 0 && ret != -ENOENT))
+		if (artxq == last || (ret < 0 && ret != -ENOENT))
 			break;
-
-		if (!first)
-			first = txq;
-
-		txq = ieee80211_next_txq(hw);
 	}
 
 	rcu_read_unlock();
+	spin_unlock_bh(&ar->txqs_lock);
 }
 
 /************/
@@ -4239,22 +4250,34 @@ static void ath10k_mac_op_tx(struct ieee80211_hw *hw,
 	}
 }
 
-static void ath10k_mac_op_wake_tx_queue(struct ieee80211_hw *hw)
+static void ath10k_mac_op_wake_tx_queue(struct ieee80211_hw *hw,
+					struct ieee80211_txq *txq)
 {
-	struct ieee80211_txq *txq;
+	struct ath10k *ar = hw->priv;
+	struct ath10k_txq *artxq = (void *)txq->drv_priv;
+	struct ieee80211_txq *f_txq;
+	struct ath10k_txq *f_artxq;
 	int ret = 0;
 	int max = 16;
 
-	txq = ieee80211_next_txq(hw);
+	spin_lock_bh(&ar->txqs_lock);
+	if (list_empty(&artxq->list))
+		list_add_tail(&artxq->list, &ar->txqs);
+
+	f_artxq = list_first_entry(&ar->txqs, struct ath10k_txq, list);
+	f_txq = container_of((void *)f_artxq, struct ieee80211_txq, drv_priv);
+	list_del_init(&f_artxq->list);
 
-	while (ath10k_mac_tx_can_push(hw, txq) && max--) {
-		ret = ath10k_mac_tx_push_txq(hw, txq);
+	while (ath10k_mac_tx_can_push(hw, f_txq) && max--) {
+		ret = ath10k_mac_tx_push_txq(hw, f_txq);
 		if (ret)
 			break;
 	}
 	if (ret != -ENOENT)
-		ieee80211_schedule_txq(hw, txq);
+		list_add_tail(&f_artxq->list, &ar->txqs);
+	spin_unlock_bh(&ar->txqs_lock);
 
+	ath10k_htt_tx_txq_update(hw, f_txq);
 	ath10k_htt_tx_txq_update(hw, txq);
 }
 

drivers/net/wireless/ath/ath9k/ath9k.h

@@ -246,8 +246,12 @@ struct ath_atx_tid {
 	s8 bar_index;
 	bool active;
 	bool clear_ps_filter;
+	bool has_queued;
 };
 
+void __ath_tx_queue_tid(struct ath_softc *sc, struct ath_atx_tid *tid);
+void ath_tx_queue_tid(struct ath_softc *sc, struct ath_atx_tid *tid);
+
 struct ath_node {
 	struct ath_softc *sc;
 	struct ieee80211_sta *sta; /* station struct we're part of */
@@ -587,7 +591,8 @@ bool ath_drain_all_txq(struct ath_softc *sc);
 void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq);
 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an);
 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an);
-void ath_txq_schedule(struct ath_softc *sc);
+void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq);
+void ath_txq_schedule_all(struct ath_softc *sc);
 int ath_tx_init(struct ath_softc *sc, int nbufs);
 int ath_txq_update(struct ath_softc *sc, int qnum,
 		   struct ath9k_tx_queue_info *q);
@@ -613,7 +618,7 @@ void ath9k_release_buffered_frames(struct ieee80211_hw *hw,
 				   u16 tids, int nframes,
 				   enum ieee80211_frame_release_type reason,
 				   bool more_data);
-void ath9k_wake_tx_queue(struct ieee80211_hw *hw);
+void ath9k_wake_tx_queue(struct ieee80211_hw *hw, struct ieee80211_txq *queue);
 
 /********/
 /* VIFs */

drivers/net/wireless/ath/ath9k/main.c

@@ -266,7 +266,7 @@ static bool ath_complete_reset(struct ath_softc *sc, bool start)
 		}
 	work:
 		ath_restart_work(sc);
-		ath_txq_schedule(sc);
+		ath_txq_schedule_all(sc);
 	}
 
 	sc->gtt_cnt = 0;

drivers/net/wireless/ath/ath9k/recv.c

@@ -1057,6 +1057,8 @@ static void ath_rx_count_airtime(struct ath_softc *sc,
  	if (!!(sc->airtime_flags & AIRTIME_USE_RX)) {
 		spin_lock_bh(&acq->lock);
 		an->airtime_deficit[acno] -= airtime;
+		if (an->airtime_deficit[acno] <= 0)
+			__ath_tx_queue_tid(sc, ATH_AN_2_TID(an, tidno));
 		spin_unlock_bh(&acq->lock);
 	}
 	ath_debug_airtime(sc, an, airtime, 0);

include/net/mac80211.h

@@ -105,12 +105,9 @@
  * The driver is expected to initialize its private per-queue data for stations
  * and interfaces in the .add_interface and .sta_add ops.
  *
- * The driver can't access the queue directly. To obtain the next queue to pull
- * frames from, the driver calls ieee80211_next_txq(). To dequeue a frame from a
- * txq, it calls ieee80211_tx_dequeue(). Whenever mac80211 adds a new frame to a
- * queue, it calls the .wake_tx_queue driver op. The driver is expected to
- * re-schedule the txq using ieee80211_schedule_txq() if it is still active
- * after the driver has finished pulling packets from it.
+ * The driver can't access the queue directly. To dequeue a frame, it calls
+ * ieee80211_tx_dequeue(). Whenever mac80211 adds a new frame to a queue, it
+ * calls the .wake_tx_queue driver op.
  *
  * For AP powersave TIM handling, the driver only needs to indicate if it has
  * buffered packets in the driver specific data structures by calling
@@ -3734,7 +3731,8 @@ struct ieee80211_ops {
 					 struct ieee80211_vif *vif,
 					 struct ieee80211_tdls_ch_sw_params *params);
 
-	void (*wake_tx_queue)(struct ieee80211_hw *hw);
+	void (*wake_tx_queue)(struct ieee80211_hw *hw,
+			      struct ieee80211_txq *txq);
 	void (*sync_rx_queues)(struct ieee80211_hw *hw);
 
 	int (*start_nan)(struct ieee80211_hw *hw,
@@ -5885,36 +5883,13 @@ void ieee80211_unreserve_tid(struct ieee80211_sta *sta, u8 tid);
  * ieee80211_tx_dequeue - dequeue a packet from a software tx queue
  *
  * @hw: pointer as obtained from ieee80211_alloc_hw()
- * @txq: pointer obtained from ieee80211_next_txq()
+ * @txq: pointer obtained from station or virtual interface
  *
  * Returns the skb if successful, %NULL if no frame was available.
  */
 struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
 				     struct ieee80211_txq *txq);
 
-/**
- * ieee80211_schedule_txq - add txq to scheduling loop
- *
- * @hw: pointer as obtained from ieee80211_alloc_hw()
- * @txq: pointer obtained from station or virtual interface
- *
- * Returns %true if the txq was actually added to the scheduling,
- * %false otherwise.
- */
-bool ieee80211_schedule_txq(struct ieee80211_hw *hw,
-			    struct ieee80211_txq *txq);
-
-/**
- * ieee80211_next_txq - get next tx queue to pull packets from
- *
- * @hw: pointer as obtained from ieee80211_alloc_hw()
- *
- * Returns the next txq if successful, %NULL if no queue is eligible. If a txq
- * is returned, it will have been removed from the scheduler queue and needs to
- * be re-scheduled with ieee80211_schedule_txq() to continue to be active.
- */
-struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw);
-
 /**
  * ieee80211_txq_get_depth - get pending frame/byte count of given txq
  *

net/mac80211/agg-tx.c

@@ -226,13 +226,9 @@ ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
 		clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
 
 	clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
-
-	if (!ieee80211_schedule_txq(&sta->sdata->local->hw, txq))
-		return;
-
 	local_bh_disable();
 	rcu_read_lock();
-	drv_wake_tx_queue(sta->sdata->local);
+	drv_wake_tx_queue(sta->sdata->local, txqi);
 	rcu_read_unlock();
 	local_bh_enable();
 }

net/mac80211/driver-ops.h

@@ -1158,10 +1158,16 @@ drv_tdls_recv_channel_switch(struct ieee80211_local *local,
 	trace_drv_return_void(local);
 }
 
-static inline void drv_wake_tx_queue(struct ieee80211_local *local)
+static inline void drv_wake_tx_queue(struct ieee80211_local *local,
+				     struct txq_info *txq)
 {
-	trace_drv_wake_tx_queue(local);
-	local->ops->wake_tx_queue(&local->hw);
+	struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->txq.vif);
+
+	if (!check_sdata_in_driver(sdata))
+		return;
+
+	trace_drv_wake_tx_queue(local, sdata, txq);
+	local->ops->wake_tx_queue(&local->hw, &txq->txq);
 }
 
 static inline int drv_start_nan(struct ieee80211_local *local,

net/mac80211/ieee80211_i.h

@@ -832,7 +832,6 @@ struct txq_info {
 	struct codel_vars def_cvars;
 	struct codel_stats cstats;
 	struct sk_buff_head frags;
-	struct list_head schedule_order;
 	unsigned long flags;
 
 	/* keep last! */
@@ -1123,10 +1122,6 @@ struct ieee80211_local {
 	struct codel_vars *cvars;
 	struct codel_params cparams;
 
-	/* protects active_txqs and txqi->schedule_order */
-	spinlock_t active_txq_lock;
-	struct list_head active_txqs;
-
 	const struct ieee80211_ops *ops;
 
 	/*

net/mac80211/main.c

@@ -619,9 +619,6 @@ struct ieee80211_hw *ieee80211_alloc_hw_nm(size_t priv_data_len,
 	spin_lock_init(&local->rx_path_lock);
 	spin_lock_init(&local->queue_stop_reason_lock);
 
-	INIT_LIST_HEAD(&local->active_txqs);
-	spin_lock_init(&local->active_txq_lock);
-
 	INIT_LIST_HEAD(&local->chanctx_list);
 	mutex_init(&local->chanctx_mtx);
 

net/mac80211/sta_info.c

@@ -1237,17 +1237,12 @@ void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
 		drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
 
 	if (sta->sta.txq[0]) {
-		bool wake = false;
-
 		for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
 			if (!txq_has_queue(sta->sta.txq[i]))
 				continue;
 
-			if (ieee80211_schedule_txq(&local->hw, sta->sta.txq[i]))
-				wake = true;
+			drv_wake_tx_queue(local, to_txq_info(sta->sta.txq[i]));
 		}
-		if (wake)
-			drv_wake_tx_queue(local);
 	}
 
 	skb_queue_head_init(&pending);

net/mac80211/trace.h

@@ -2550,9 +2550,35 @@ TRACE_EVENT(drv_tdls_recv_channel_switch,
 	)
 );
 
-DEFINE_EVENT(local_only_evt, drv_wake_tx_queue,
-	     TP_PROTO(struct ieee80211_local *local),
-	     TP_ARGS(local)
+TRACE_EVENT(drv_wake_tx_queue,
+	TP_PROTO(struct ieee80211_local *local,
+		 struct ieee80211_sub_if_data *sdata,
+		 struct txq_info *txq),
+
+	TP_ARGS(local, sdata, txq),
+
+	TP_STRUCT__entry(
+		LOCAL_ENTRY
+		VIF_ENTRY
+		STA_ENTRY
+		__field(u8, ac)
+		__field(u8, tid)
+	),
+
+	TP_fast_assign(
+		struct ieee80211_sta *sta = txq->txq.sta;
+
+		LOCAL_ASSIGN;
+		VIF_ASSIGN;
+		STA_ASSIGN;
+		__entry->ac = txq->txq.ac;
+		__entry->tid = txq->txq.tid;
+	),
+
+	TP_printk(
+		LOCAL_PR_FMT  VIF_PR_FMT  STA_PR_FMT " ac:%d tid:%d",
+		LOCAL_PR_ARG, VIF_PR_ARG, STA_PR_ARG, __entry->ac, __entry->tid
+	)
 );
 
 #endif /* !__MAC80211_DRIVER_TRACE || TRACE_HEADER_MULTI_READ */

net/mac80211/tx.c

@@ -1439,7 +1439,6 @@ void ieee80211_txq_init(struct ieee80211_sub_if_data *sdata,
 	codel_vars_init(&txqi->def_cvars);
 	codel_stats_init(&txqi->cstats);
 	__skb_queue_head_init(&txqi->frags);
-	INIT_LIST_HEAD(&txqi->schedule_order);
 
 	txqi->txq.vif = &sdata->vif;
 
@@ -1463,7 +1462,6 @@ void ieee80211_txq_purge(struct ieee80211_local *local,
 
 	fq_tin_reset(fq, tin, fq_skb_free_func);
 	ieee80211_purge_tx_queue(&local->hw, &txqi->frags);
-	list_del_init(&txqi->schedule_order);
 }
 
 int ieee80211_txq_setup_flows(struct ieee80211_local *local)
@@ -1560,8 +1558,7 @@ static bool ieee80211_queue_skb(struct ieee80211_local *local,
 	ieee80211_txq_enqueue(local, txqi, skb);
 	spin_unlock_bh(&fq->lock);
 
-	if (ieee80211_schedule_txq(&local->hw, &txqi->txq))
-		drv_wake_tx_queue(local);
+	drv_wake_tx_queue(local, txqi);
 
 	return true;
 }
@@ -3556,50 +3553,6 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_tx_dequeue);
 
-bool ieee80211_schedule_txq(struct ieee80211_hw *hw,
-			    struct ieee80211_txq *txq)
-{
-	struct ieee80211_local *local = hw_to_local(hw);
-	struct txq_info *txqi = to_txq_info(txq);
-	bool ret = false;
-
-	spin_lock_bh(&local->active_txq_lock);
-
-	if (list_empty(&txqi->schedule_order)) {
-		list_add_tail(&txqi->schedule_order, &local->active_txqs);
-		ret = true;
-	}
-
-	spin_unlock_bh(&local->active_txq_lock);
-
-	return ret;
-}
-EXPORT_SYMBOL(ieee80211_schedule_txq);
-
-struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw)
-{
-	struct ieee80211_local *local = hw_to_local(hw);
-	struct txq_info *txqi = NULL;
-
-	spin_lock_bh(&local->active_txq_lock);
-
-	if (list_empty(&local->active_txqs))
-		goto out;
-
-	txqi = list_first_entry(&local->active_txqs,
-				struct txq_info, schedule_order);
-	list_del_init(&txqi->schedule_order);
-
-out:
-	spin_unlock_bh(&local->active_txq_lock);
-
-	if (!txqi)
-		return NULL;
-
-	return &txqi->txq;
-}
-EXPORT_SYMBOL(ieee80211_next_txq);
-
 void __ieee80211_subif_start_xmit(struct sk_buff *skb,
 				  struct net_device *dev,
 				  u32 info_flags)