ath9k: Add airtime fairness scheduler

This adds a patch that introduces airtime fairness scheduling to ath9k,
which can significantly improve network efficiency in mixed-rate
environments.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

9 files changed, 728 insertions, 15 deletions

diff --git a/package/kernel/mac80211/patches/344-ath9k-Introduce-airtime-fairness-scheduling-between-.patch b/package/kernel/mac80211/patches/344-ath9k-Introduce-airtime-fairness-scheduling-between-.patch
new file mode 100644
index 0000000..10c6573
--- /dev/null
+++ b/package/kernel/mac80211/patches/344-ath9k-Introduce-airtime-fairness-scheduling-between-.patch
@@ -0,0 +1,651 @@
+From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
+Date: Mon, 5 Dec 2016 13:27:37 +0200
+Subject: [PATCH] ath9k: Introduce airtime fairness scheduling between stations
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This reworks the ath9k driver to schedule transmissions to connected
+stations in a way that enforces airtime fairness between them. It
+accomplishes this by measuring the time spent transmitting to or
+receiving from a station at TX and RX completion, and accounting this to
+a per-station, per-QoS level airtime deficit. Then, an FQ-CoDel based
+deficit scheduler is employed at packet dequeue time, to control which
+station gets the next transmission opportunity.
+
+Airtime fairness can significantly improve the efficiency of the network
+when station rates vary. The following throughput values are from a
+simple three-station test scenario, where two stations operate at the
+highest HT20 rate, and one station at the lowest, and the scheduler is
+employed at the access point:
+
+                  Before   /   After
+Fast station 1:    19.17   /   25.09 Mbps
+Fast station 2:    19.83   /   25.21 Mbps
+Slow station:       2.58   /    1.77 Mbps
+Total:             41.58   /   52.07 Mbps
+
+The benefit of airtime fairness goes up the more stations are present.
+In a 30-station test with one station artificially limited to 1 Mbps,
+we have seen aggregate throughput go from 2.14 to 17.76 Mbps.
+
+Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
+Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
+---
+
+--- a/drivers/net/wireless/ath/ath9k/ath9k.h
++++ b/drivers/net/wireless/ath/ath9k/ath9k.h
+@@ -112,6 +112,8 @@ int ath_descdma_setup(struct ath_softc *
+ #define ATH_TXFIFO_DEPTH           8
+ #define ATH_TX_ERROR               0x01
+ 
++#define ATH_AIRTIME_QUANTUM        300 /* usec */
++
+ /* Stop tx traffic 1ms before the GO goes away */
+ #define ATH_P2P_PS_STOP_TIME       1000
+ 
+@@ -247,6 +249,9 @@ struct ath_atx_tid {
+ 	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 */
+@@ -258,9 +263,12 @@ struct ath_node {
+ 
+ 	bool sleeping;
+ 	bool no_ps_filter;
++	s64 airtime_deficit[IEEE80211_NUM_ACS];
++	u32 airtime_rx_start;
+ 
+ #ifdef CPTCFG_ATH9K_STATION_STATISTICS
+ 	struct ath_rx_rate_stats rx_rate_stats;
++	struct ath_airtime_stats airtime_stats;
+ #endif
+ 	u8 key_idx[4];
+ 
+@@ -317,10 +325,16 @@ struct ath_rx {
+ /* Channel Context */
+ /*******************/
+ 
++struct ath_acq {
++	struct list_head acq_new;
++	struct list_head acq_old;
++	spinlock_t lock;
++};
++
+ struct ath_chanctx {
+ 	struct cfg80211_chan_def chandef;
+ 	struct list_head vifs;
+-	struct list_head acq[IEEE80211_NUM_ACS];
++	struct ath_acq acq[IEEE80211_NUM_ACS];
+ 	int hw_queue_base;
+ 
+ 	/* do not dereference, use for comparison only */
+@@ -575,6 +589,8 @@ void ath_txq_schedule_all(struct ath_sof
+ 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);
++u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
++		     int width, int half_gi, bool shortPreamble);
+ void ath_update_max_aggr_framelen(struct ath_softc *sc, int queue, int txop);
+ void ath_assign_seq(struct ath_common *common, struct sk_buff *skb);
+ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
+@@ -963,6 +979,11 @@ void ath_ant_comb_scan(struct ath_softc
+ 
+ #define ATH9K_NUM_CHANCTX  2 /* supports 2 operating channels */
+ 
++#define AIRTIME_USE_TX		BIT(0)
++#define AIRTIME_USE_RX		BIT(1)
++#define AIRTIME_USE_NEW_QUEUES	BIT(2)
++#define AIRTIME_ACTIVE(flags) (!!(flags & (AIRTIME_USE_TX|AIRTIME_USE_RX)))
++
+ struct ath_softc {
+ 	struct ieee80211_hw *hw;
+ 	struct device *dev;
+@@ -1005,6 +1026,8 @@ struct ath_softc {
+ 	short nbcnvifs;
+ 	unsigned long ps_usecount;
+ 
++	u16 airtime_flags; /* AIRTIME_* */
++
+ 	struct ath_rx rx;
+ 	struct ath_tx tx;
+ 	struct ath_beacon beacon;
+--- a/drivers/net/wireless/ath/ath9k/channel.c
++++ b/drivers/net/wireless/ath/ath9k/channel.c
+@@ -118,8 +118,11 @@ void ath_chanctx_init(struct ath_softc *
+ 		INIT_LIST_HEAD(&ctx->vifs);
+ 		ctx->txpower = ATH_TXPOWER_MAX;
+ 		ctx->flush_timeout = HZ / 5; /* 200ms */
+-		for (j = 0; j < ARRAY_SIZE(ctx->acq); j++)
+-			INIT_LIST_HEAD(&ctx->acq[j]);
++		for (j = 0; j < ARRAY_SIZE(ctx->acq); j++) {
++			INIT_LIST_HEAD(&ctx->acq[j].acq_new);
++			INIT_LIST_HEAD(&ctx->acq[j].acq_old);
++			spin_lock_init(&ctx->acq[j].lock);
++		}
+ 	}
+ }
+ 
+@@ -1345,8 +1348,11 @@ void ath9k_offchannel_init(struct ath_so
+ 	ctx->txpower = ATH_TXPOWER_MAX;
+ 	cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
+ 
+-	for (i = 0; i < ARRAY_SIZE(ctx->acq); i++)
+-		INIT_LIST_HEAD(&ctx->acq[i]);
++	for (i = 0; i < ARRAY_SIZE(ctx->acq); i++) {
++		INIT_LIST_HEAD(&ctx->acq[i].acq_new);
++		INIT_LIST_HEAD(&ctx->acq[i].acq_old);
++		spin_lock_init(&ctx->acq[i].lock);
++	}
+ 
+ 	sc->offchannel.chan.offchannel = true;
+ }
+--- a/drivers/net/wireless/ath/ath9k/debug.c
++++ b/drivers/net/wireless/ath/ath9k/debug.c
+@@ -1399,5 +1399,8 @@ int ath9k_init_debug(struct ath_hw *ah)
+ 	debugfs_create_file("tpc", S_IRUSR | S_IWUSR,
+ 			    sc->debug.debugfs_phy, sc, &fops_tpc);
+ 
++	debugfs_create_u16("airtime_flags", S_IRUSR | S_IWUSR,
++			   sc->debug.debugfs_phy, &sc->airtime_flags);
++
+ 	return 0;
+ }
+--- a/drivers/net/wireless/ath/ath9k/debug.h
++++ b/drivers/net/wireless/ath/ath9k/debug.h
+@@ -221,6 +221,11 @@ struct ath_rx_rate_stats {
+ 	} cck_stats[4];
+ };
+ 
++struct ath_airtime_stats {
++	u32 rx_airtime;
++	u32 tx_airtime;
++};
++
+ #define ANT_MAIN 0
+ #define ANT_ALT  1
+ 
+@@ -314,12 +319,20 @@ ath9k_debug_sync_cause(struct ath_softc
+ void ath_debug_rate_stats(struct ath_softc *sc,
+ 			  struct ath_rx_status *rs,
+ 			  struct sk_buff *skb);
++void ath_debug_airtime(struct ath_softc *sc,
++		       struct ath_node *an,
++		       u32 rx, u32 tx);
+ #else
+ static inline void ath_debug_rate_stats(struct ath_softc *sc,
+ 					struct ath_rx_status *rs,
+ 					struct sk_buff *skb)
+ {
+ }
++static inline void ath_debug_airtime(struct ath_softc *sc,
++			      struct ath_node *an,
++			      u32 rx, u32 tx)
++{
++}
+ #endif /* CPTCFG_ATH9K_STATION_STATISTICS */
+ 
+ #endif /* DEBUG_H */
+--- a/drivers/net/wireless/ath/ath9k/debug_sta.c
++++ b/drivers/net/wireless/ath/ath9k/debug_sta.c
+@@ -242,6 +242,59 @@ static const struct file_operations fops
+ 	.llseek = default_llseek,
+ };
+ 
++void ath_debug_airtime(struct ath_softc *sc,
++		struct ath_node *an,
++		u32 rx,
++		u32 tx)
++{
++	struct ath_airtime_stats *astats = &an->airtime_stats;
++
++	astats->rx_airtime += rx;
++	astats->tx_airtime += tx;
++}
++
++static ssize_t read_airtime(struct file *file, char __user *user_buf,
++			size_t count, loff_t *ppos)
++{
++	struct ath_node *an = file->private_data;
++	struct ath_airtime_stats *astats;
++	static const char *qname[4] = {
++		"VO", "VI", "BE", "BK"
++	};
++	u32 len = 0, size = 256;
++	char *buf;
++	size_t retval;
++	int i;
++
++	buf = kzalloc(size, GFP_KERNEL);
++	if (buf == NULL)
++		return -ENOMEM;
++
++	astats = &an->airtime_stats;
++
++	len += scnprintf(buf + len, size - len, "RX: %u us\n", astats->rx_airtime);
++	len += scnprintf(buf + len, size - len, "TX: %u us\n", astats->tx_airtime);
++	len += scnprintf(buf + len, size - len, "Deficit: ");
++	for (i = 0; i < 4; i++)
++		len += scnprintf(buf+len, size - len, "%s: %lld us ", qname[i], an->airtime_deficit[i]);
++	if (len < size)
++		buf[len++] = '\n';
++
++	retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
++	kfree(buf);
++
++	return retval;
++}
++
++
++static const struct file_operations fops_airtime = {
++	.read = read_airtime,
++	.open = simple_open,
++	.owner = THIS_MODULE,
++	.llseek = default_llseek,
++};
++
++
+ void ath9k_sta_add_debugfs(struct ieee80211_hw *hw,
+ 			   struct ieee80211_vif *vif,
+ 			   struct ieee80211_sta *sta,
+@@ -251,4 +304,5 @@ void ath9k_sta_add_debugfs(struct ieee80
+ 
+ 	debugfs_create_file("node_aggr", S_IRUGO, dir, an, &fops_node_aggr);
+ 	debugfs_create_file("node_recv", S_IRUGO, dir, an, &fops_node_recv);
++	debugfs_create_file("airtime", S_IRUGO, dir, an, &fops_airtime);
+ }
+--- a/drivers/net/wireless/ath/ath9k/init.c
++++ b/drivers/net/wireless/ath/ath9k/init.c
+@@ -620,6 +620,8 @@ static int ath9k_init_softc(u16 devid, s
+ 
+ 	/* Will be cleared in ath9k_start() */
+ 	set_bit(ATH_OP_INVALID, &common->op_flags);
++	sc->airtime_flags = (AIRTIME_USE_TX | AIRTIME_USE_RX |
++			     AIRTIME_USE_NEW_QUEUES);
+ 
+ 	sc->sc_ah = ah;
+ 	sc->dfs_detector = dfs_pattern_detector_init(common, NL80211_DFS_UNSET);
+--- a/drivers/net/wireless/ath/ath9k/main.c
++++ b/drivers/net/wireless/ath/ath9k/main.c
+@@ -70,10 +70,10 @@ static bool ath9k_has_pending_frames(str
+ 		goto out;
+ 
+ 	if (txq->mac80211_qnum >= 0) {
+-		struct list_head *list;
++		struct ath_acq *acq;
+ 
+-		list = &sc->cur_chan->acq[txq->mac80211_qnum];
+-		if (!list_empty(list))
++		acq = &sc->cur_chan->acq[txq->mac80211_qnum];
++		if (!list_empty(&acq->acq_new) || !list_empty(&acq->acq_old))
+ 			pending = true;
+ 	}
+ out:
+--- a/drivers/net/wireless/ath/ath9k/recv.c
++++ b/drivers/net/wireless/ath/ath9k/recv.c
+@@ -991,6 +991,70 @@ static void ath9k_apply_ampdu_details(st
+ 	}
+ }
+ 
++static void ath_rx_count_airtime(struct ath_softc *sc,
++				 struct ath_rx_status *rs,
++				 struct sk_buff *skb)
++{
++	struct ath_node *an;
++	struct ath_acq *acq;
++	struct ath_vif *avp;
++	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
++	struct ath_hw *ah = sc->sc_ah;
++	struct ath_common *common = ath9k_hw_common(ah);
++	struct ieee80211_sta *sta;
++	struct ieee80211_rx_status *rxs;
++	const struct ieee80211_rate *rate;
++	bool is_sgi, is_40, is_sp;
++	int phy;
++	u16 len = rs->rs_datalen;
++	u32 airtime = 0;
++	u8 tidno, acno;
++
++	if (!ieee80211_is_data(hdr->frame_control))
++		return;
++
++	rcu_read_lock();
++
++	sta = ieee80211_find_sta_by_ifaddr(sc->hw, hdr->addr2, NULL);
++	if (!sta)
++		goto exit;
++	an = (struct ath_node *) sta->drv_priv;
++	avp = (struct ath_vif *) an->vif->drv_priv;
++	tidno = skb->priority & IEEE80211_QOS_CTL_TID_MASK;
++	acno = TID_TO_WME_AC(tidno);
++	acq = &avp->chanctx->acq[acno];
++
++	rxs = IEEE80211_SKB_RXCB(skb);
++
++	is_sgi = !!(rxs->flag & RX_FLAG_SHORT_GI);
++	is_40 = !!(rxs->flag & RX_FLAG_40MHZ);
++	is_sp = !!(rxs->flag & RX_FLAG_SHORTPRE);
++
++	if (!!(rxs->flag & RX_FLAG_HT)) {
++		/* MCS rates */
++
++		airtime += ath_pkt_duration(sc, rxs->rate_idx, len,
++					is_40, is_sgi, is_sp);
++	} else {
++
++		phy = IS_CCK_RATE(rs->rs_rate) ? WLAN_RC_PHY_CCK : WLAN_RC_PHY_OFDM;
++		rate = &common->sbands[rxs->band].bitrates[rxs->rate_idx];
++		airtime += ath9k_hw_computetxtime(ah, phy, rate->bitrate * 100,
++						len, rxs->rate_idx, is_sp);
++	}
++
++ 	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);
++exit:
++	rcu_read_unlock();
++}
++
+ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
+ {
+ 	struct ath_rxbuf *bf;
+@@ -1137,6 +1201,7 @@ int ath_rx_tasklet(struct ath_softc *sc,
+ 		ath9k_antenna_check(sc, &rs);
+ 		ath9k_apply_ampdu_details(sc, &rs, rxs);
+ 		ath_debug_rate_stats(sc, &rs, skb);
++		ath_rx_count_airtime(sc, &rs, skb);
+ 
+ 		hdr = (struct ieee80211_hdr *)skb->data;
+ 		if (ieee80211_is_ack(hdr->frame_control))
+--- a/drivers/net/wireless/ath/ath9k/xmit.c
++++ b/drivers/net/wireless/ath/ath9k/xmit.c
+@@ -125,21 +125,44 @@ void ath_txq_unlock_complete(struct ath_
+ 		ath_tx_status(hw, skb);
+ }
+ 
+-static void ath_tx_queue_tid(struct ath_softc *sc, struct ath_txq *txq,
+-			     struct ath_atx_tid *tid)
++void __ath_tx_queue_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
+ {
+-	struct list_head *list;
+ 	struct ath_vif *avp = (struct ath_vif *) tid->an->vif->drv_priv;
+ 	struct ath_chanctx *ctx = avp->chanctx;
++	struct ath_acq *acq;
++	struct list_head *tid_list;
++	u8 acno = TID_TO_WME_AC(tid->tidno);
+ 
+-	if (!ctx)
++	if (!ctx || !list_empty(&tid->list))
+ 		return;
+ 
+-	list = &ctx->acq[TID_TO_WME_AC(tid->tidno)];
+-	if (list_empty(&tid->list))
+-		list_add_tail(&tid->list, list);
++
++	acq = &ctx->acq[acno];
++	if ((sc->airtime_flags & AIRTIME_USE_NEW_QUEUES) &&
++	    tid->an->airtime_deficit[acno] > 0)
++		tid_list = &acq->acq_new;
++	else
++		tid_list = &acq->acq_old;
++
++	list_add_tail(&tid->list, tid_list);
+ }
+ 
++void ath_tx_queue_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
++{
++	struct ath_vif *avp = (struct ath_vif *) tid->an->vif->drv_priv;
++	struct ath_chanctx *ctx = avp->chanctx;
++	struct ath_acq *acq;
++
++	if (!ctx || !list_empty(&tid->list))
++		return;
++
++	acq = &ctx->acq[TID_TO_WME_AC(tid->tidno)];
++	spin_lock_bh(&acq->lock);
++	__ath_tx_queue_tid(sc, tid);
++	spin_unlock_bh(&acq->lock);
++}
++
++
+ void ath9k_wake_tx_queue(struct ieee80211_hw *hw, struct ieee80211_txq *queue)
+ {
+ 	struct ath_softc *sc = hw->priv;
+@@ -154,7 +177,7 @@ void ath9k_wake_tx_queue(struct ieee8021
+ 	ath_txq_lock(sc, txq);
+ 
+ 	tid->has_queued = true;
+-	ath_tx_queue_tid(sc, txq, tid);
++	ath_tx_queue_tid(sc, tid);
+ 	ath_txq_schedule(sc, txq);
+ 
+ 	ath_txq_unlock(sc, txq);
+@@ -684,7 +707,7 @@ static void ath_tx_complete_aggr(struct
+ 
+ 		skb_queue_splice_tail(&bf_pending, &tid->retry_q);
+ 		if (!an->sleeping) {
+-			ath_tx_queue_tid(sc, txq, tid);
++			ath_tx_queue_tid(sc, tid);
+ 
+ 			if (ts->ts_status & (ATH9K_TXERR_FILT | ATH9K_TXERR_XRETRY))
+ 				tid->clear_ps_filter = true;
+@@ -712,6 +735,53 @@ static bool bf_is_ampdu_not_probing(stru
+     return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
+ }
+ 
++static void ath_tx_count_airtime(struct ath_softc *sc, struct ath_txq *txq,
++				 struct ath_buf *bf, struct ath_tx_status *ts)
++{
++	struct ath_node *an;
++	struct ath_acq *acq = &sc->cur_chan->acq[txq->mac80211_qnum];
++	struct sk_buff *skb;
++	struct ieee80211_hdr *hdr;
++	struct ieee80211_hw *hw = sc->hw;
++	struct ieee80211_tx_rate rates[4];
++	struct ieee80211_sta *sta;
++	int i;
++	u32 airtime = 0;
++
++	skb = bf->bf_mpdu;
++	if(!skb)
++		return;
++
++	hdr = (struct ieee80211_hdr *)skb->data;
++	memcpy(rates, bf->rates, sizeof(rates));
++
++	rcu_read_lock();
++
++	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
++	if(!sta)
++		goto exit;
++
++
++	an = (struct ath_node *) sta->drv_priv;
++
++	airtime += ts->duration * (ts->ts_longretry + 1);
++
++	for(i=0; i < ts->ts_rateindex; i++)
++		airtime += ath9k_hw_get_duration(sc->sc_ah, bf->bf_desc, i) * rates[i].count;
++
++	if (!!(sc->airtime_flags & AIRTIME_USE_TX)) {
++		spin_lock_bh(&acq->lock);
++		an->airtime_deficit[txq->mac80211_qnum] -= airtime;
++		if (an->airtime_deficit[txq->mac80211_qnum] <= 0)
++			__ath_tx_queue_tid(sc, ath_get_skb_tid(sc, an, skb));
++		spin_unlock_bh(&acq->lock);
++	}
++	ath_debug_airtime(sc, an, 0, airtime);
++
++exit:
++	rcu_read_unlock();
++}
++
+ static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
+ 				  struct ath_tx_status *ts, struct ath_buf *bf,
+ 				  struct list_head *bf_head)
+@@ -733,6 +803,7 @@ static void ath_tx_process_buffer(struct
+ 
+ 	ts->duration = ath9k_hw_get_duration(sc->sc_ah, bf->bf_desc,
+ 					     ts->ts_rateindex);
++	ath_tx_count_airtime(sc, txq, bf, ts);
+ 
+ 	hdr = (struct ieee80211_hdr *) bf->bf_mpdu->data;
+ 	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
+@@ -1094,8 +1165,8 @@ finish:
+  * width  - 0 for 20 MHz, 1 for 40 MHz
+  * half_gi - to use 4us v/s 3.6 us for symbol time
+  */
+-static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
+-			    int width, int half_gi, bool shortPreamble)
++u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
++		     int width, int half_gi, bool shortPreamble)
+ {
+ 	u32 nbits, nsymbits, duration, nsymbols;
+ 	int streams;
+@@ -1493,7 +1564,7 @@ ath_tx_form_burst(struct ath_softc *sc,
+ }
+ 
+ static bool ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
+-			      struct ath_atx_tid *tid, bool *stop)
++			      struct ath_atx_tid *tid)
+ {
+ 	struct ath_buf *bf;
+ 	struct ieee80211_tx_info *tx_info;
+@@ -1515,7 +1586,6 @@ static bool ath_tx_sched_aggr(struct ath
+ 	if ((aggr && txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) ||
+ 	    (!aggr && txq->axq_depth >= ATH_NON_AGGR_MIN_QDEPTH)) {
+ 		__skb_queue_tail(&tid->retry_q, bf->bf_mpdu);
+-		*stop = true;
+ 		return false;
+ 	}
+ 
+@@ -1639,7 +1709,7 @@ void ath_tx_aggr_wakeup(struct ath_softc
+ 		ath_txq_lock(sc, txq);
+ 		tid->clear_ps_filter = true;
+ 		if (ath_tid_has_buffered(tid)) {
+-			ath_tx_queue_tid(sc, txq, tid);
++			ath_tx_queue_tid(sc, tid);
+ 			ath_txq_schedule(sc, txq);
+ 		}
+ 		ath_txq_unlock_complete(sc, txq);
+@@ -1956,9 +2026,10 @@ void ath_tx_cleanupq(struct ath_softc *s
+ void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
+ {
+ 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+-	struct ath_atx_tid *tid, *last_tid;
++	struct ath_atx_tid *tid;
+ 	struct list_head *tid_list;
+-	bool sent = false;
++	struct ath_acq *acq;
++	bool active = AIRTIME_ACTIVE(sc->airtime_flags);
+ 
+ 	if (txq->mac80211_qnum < 0)
+ 		return;
+@@ -1967,48 +2038,55 @@ void ath_txq_schedule(struct ath_softc *
+ 		return;
+ 
+ 	spin_lock_bh(&sc->chan_lock);
+-	tid_list = &sc->cur_chan->acq[txq->mac80211_qnum];
+-
+-	if (list_empty(tid_list)) {
+-		spin_unlock_bh(&sc->chan_lock);
+-		return;
+-	}
+-
+ 	rcu_read_lock();
++	acq = &sc->cur_chan->acq[txq->mac80211_qnum];
+ 
+-	last_tid = list_entry(tid_list->prev, struct ath_atx_tid, list);
+-	while (!list_empty(tid_list)) {
+-		bool stop = false;
+-
+-		if (sc->cur_chan->stopped)
+-			break;
+-
+-		tid = list_first_entry(tid_list, struct ath_atx_tid, list);
+-		list_del_init(&tid->list);
++	if (sc->cur_chan->stopped)
++		goto out;
+ 
+-		if (ath_tx_sched_aggr(sc, txq, tid, &stop))
+-			sent = true;
++begin:
++	tid_list = &acq->acq_new;
++	if (list_empty(tid_list)) {
++		tid_list = &acq->acq_old;
++		if (list_empty(tid_list))
++			goto out;
++	}
++	tid = list_first_entry(tid_list, struct ath_atx_tid, list);
+ 
+-		/*
+-		 * add tid to round-robin queue if more frames
+-		 * are pending for the tid
+-		 */
+-		if (ath_tid_has_buffered(tid))
+-			ath_tx_queue_tid(sc, txq, tid);
++	if (active && tid->an->airtime_deficit[txq->mac80211_qnum] <= 0) {
++		spin_lock_bh(&acq->lock);
++		tid->an->airtime_deficit[txq->mac80211_qnum] += ATH_AIRTIME_QUANTUM;
++		list_move_tail(&tid->list, &acq->acq_old);
++		spin_unlock_bh(&acq->lock);
++		goto begin;
++	}
+ 
+-		if (stop)
+-			break;
++	if (!ath_tid_has_buffered(tid)) {
++		spin_lock_bh(&acq->lock);
++		if ((tid_list == &acq->acq_new) && !list_empty(&acq->acq_old))
++			list_move_tail(&tid->list, &acq->acq_old);
++		else {
++			list_del_init(&tid->list);
++		}
++		spin_unlock_bh(&acq->lock);
++		goto begin;
++	}
+ 
+-		if (tid == last_tid) {
+-			if (!sent)
+-				break;
+ 
+-			sent = false;
+-			last_tid = list_entry(tid_list->prev,
+-					      struct ath_atx_tid, list);
++	/*
++	 * If we succeed in scheduling something, immediately restart to make
++	 * sure we keep the HW busy.
++	 */
++	if(ath_tx_sched_aggr(sc, txq, tid)) {
++		if (!active) {
++			spin_lock_bh(&acq->lock);
++			list_move_tail(&tid->list, &acq->acq_old);
++			spin_unlock_bh(&acq->lock);
+ 		}
++		goto begin;
+ 	}
+ 
++out:
+ 	rcu_read_unlock();
+ 	spin_unlock_bh(&sc->chan_lock);
+ }
+@@ -2862,6 +2940,9 @@ void ath_tx_node_init(struct ath_softc *
+ 	struct ath_atx_tid *tid;
+ 	int tidno, acno;
+ 
++	for (acno = 0; acno < IEEE80211_NUM_ACS; acno++)
++		an->airtime_deficit[acno] = ATH_AIRTIME_QUANTUM;
++
+ 	for (tidno = 0; tidno < IEEE80211_NUM_TIDS; tidno++) {
+ 		tid = ath_node_to_tid(an, tidno);
+ 		tid->an        = an;
diff --git a/package/kernel/mac80211/patches/345-ath9k-Turn-ath_txq_lock-unlock-into-static-inlines.patch b/package/kernel/mac80211/patches/345-ath9k-Turn-ath_txq_lock-unlock-into-static-inlines.patch
new file mode 100644
index 0000000..734ba22
--- /dev/null
+++ b/package/kernel/mac80211/patches/345-ath9k-Turn-ath_txq_lock-unlock-into-static-inlines.patch
@@ -0,0 +1,62 @@
+From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
+Date: Mon, 5 Dec 2016 13:27:38 +0200
+Subject: [PATCH] ath9k: Turn ath_txq_lock/unlock() into static inlines.
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+These are one-line functions that just call spin_lock/unlock_bh(); turn
+them into static inlines to avoid the function call overhead.
+
+Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
+Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
+---
+
+--- a/drivers/net/wireless/ath/ath9k/ath9k.h
++++ b/drivers/net/wireless/ath/ath9k/ath9k.h
+@@ -569,6 +569,15 @@ static inline void ath_chanctx_check_act
+ 
+ #endif /* CPTCFG_ATH9K_CHANNEL_CONTEXT */
+ 
++static inline void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq)
++{
++	spin_lock_bh(&txq->axq_lock);
++}
++static inline void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq)
++{
++	spin_unlock_bh(&txq->axq_lock);
++}
++
+ void ath_startrecv(struct ath_softc *sc);
+ bool ath_stoprecv(struct ath_softc *sc);
+ u32 ath_calcrxfilter(struct ath_softc *sc);
+@@ -576,8 +585,6 @@ int ath_rx_init(struct ath_softc *sc, in
+ void ath_rx_cleanup(struct ath_softc *sc);
+ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp);
+ struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype);
+-void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq);
+-void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq);
+ void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq);
+ void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq);
+ bool ath_drain_all_txq(struct ath_softc *sc);
+--- a/drivers/net/wireless/ath/ath9k/xmit.c
++++ b/drivers/net/wireless/ath/ath9k/xmit.c
+@@ -98,18 +98,6 @@ static void ath_tx_status(struct ieee802
+ 	dev_kfree_skb(skb);
+ }
+ 
+-void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq)
+-	__acquires(&txq->axq_lock)
+-{
+-	spin_lock_bh(&txq->axq_lock);
+-}
+-
+-void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq)
+-	__releases(&txq->axq_lock)
+-{
+-	spin_unlock_bh(&txq->axq_lock);
+-}
+-
+ void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq)
+ 	__releases(&txq->axq_lock)
+ {
diff --git a/package/kernel/mac80211/patches/410-ath9k_allow_adhoc_and_ap.patch b/package/kernel/mac80211/patches/410-ath9k_allow_adhoc_and_ap.patch
index 0fc30bb..f15c451 100644
--- a/package/kernel/mac80211/patches/410-ath9k_allow_adhoc_and_ap.patch
+++ b/package/kernel/mac80211/patches/410-ath9k_allow_adhoc_and_ap.patch
@@ -1,6 +1,6 @@
 --- a/drivers/net/wireless/ath/ath9k/init.c
 +++ b/drivers/net/wireless/ath/ath9k/init.c
-@@ -773,6 +773,7 @@ static const struct ieee80211_iface_limi
+@@ -775,6 +775,7 @@ static const struct ieee80211_iface_limi
  				 BIT(NL80211_IFTYPE_AP) },
  	{ .max = 1,	.types = BIT(NL80211_IFTYPE_P2P_CLIENT) |
  				 BIT(NL80211_IFTYPE_P2P_GO) },
diff --git a/package/kernel/mac80211/patches/501-ath9k_ahb_init.patch b/package/kernel/mac80211/patches/501-ath9k_ahb_init.patch
index 4f52c12..5c357cf 100644
--- a/package/kernel/mac80211/patches/501-ath9k_ahb_init.patch
+++ b/package/kernel/mac80211/patches/501-ath9k_ahb_init.patch
@@ -1,6 +1,6 @@
 --- a/drivers/net/wireless/ath/ath9k/init.c
 +++ b/drivers/net/wireless/ath/ath9k/init.c
-@@ -1076,23 +1076,23 @@ static int __init ath9k_init(void)
+@@ -1078,23 +1078,23 @@ static int __init ath9k_init(void)
  {
  	int error;
  
diff --git a/package/kernel/mac80211/patches/530-ath9k_extra_leds.patch b/package/kernel/mac80211/patches/530-ath9k_extra_leds.patch
index 3fbe316..84ace7b 100644
--- a/package/kernel/mac80211/patches/530-ath9k_extra_leds.patch
+++ b/package/kernel/mac80211/patches/530-ath9k_extra_leds.patch
@@ -1,6 +1,6 @@
 --- a/drivers/net/wireless/ath/ath9k/ath9k.h
 +++ b/drivers/net/wireless/ath/ath9k/ath9k.h
-@@ -827,6 +827,9 @@ static inline int ath9k_dump_btcoex(stru
+@@ -850,6 +850,9 @@ static inline int ath9k_dump_btcoex(stru
  #ifdef CPTCFG_MAC80211_LEDS
  void ath_init_leds(struct ath_softc *sc);
  void ath_deinit_leds(struct ath_softc *sc);
@@ -10,9 +10,9 @@
  #else
  static inline void ath_init_leds(struct ath_softc *sc)
  {
-@@ -963,6 +966,13 @@ void ath_ant_comb_scan(struct ath_softc
- 
- #define ATH9K_NUM_CHANCTX  2 /* supports 2 operating channels */
+@@ -991,6 +994,13 @@ void ath_ant_comb_scan(struct ath_softc
+ #define AIRTIME_USE_NEW_QUEUES	BIT(2)
+ #define AIRTIME_ACTIVE(flags) (!!(flags & (AIRTIME_USE_TX|AIRTIME_USE_RX)))
  
 +struct ath_led {
 +	struct list_head list;
@@ -24,7 +24,7 @@
  struct ath_softc {
  	struct ieee80211_hw *hw;
  	struct device *dev;
-@@ -1015,9 +1025,8 @@ struct ath_softc {
+@@ -1045,9 +1055,8 @@ struct ath_softc {
  	spinlock_t chan_lock;
  
  #ifdef CPTCFG_MAC80211_LEDS
@@ -181,7 +181,7 @@
  
 --- a/drivers/net/wireless/ath/ath9k/init.c
 +++ b/drivers/net/wireless/ath/ath9k/init.c
-@@ -988,7 +988,7 @@ int ath9k_init_device(u16 devid, struct
+@@ -990,7 +990,7 @@ int ath9k_init_device(u16 devid, struct
  
  #ifdef CPTCFG_MAC80211_LEDS
  	/* must be initialized before ieee80211_register_hw */
diff --git a/package/kernel/mac80211/patches/543-ath9k_entropy_from_adc.patch b/package/kernel/mac80211/patches/543-ath9k_entropy_from_adc.patch
index 237c321..7782479 100644
--- a/package/kernel/mac80211/patches/543-ath9k_entropy_from_adc.patch
+++ b/package/kernel/mac80211/patches/543-ath9k_entropy_from_adc.patch
@@ -55,7 +55,7 @@
  	ops->spectral_scan_config = ar9003_hw_spectral_scan_config;
 --- a/drivers/net/wireless/ath/ath9k/init.c
 +++ b/drivers/net/wireless/ath/ath9k/init.c
-@@ -761,7 +761,8 @@ static void ath9k_init_txpower_limits(st
+@@ -763,7 +763,8 @@ static void ath9k_init_txpower_limits(st
  	if (ah->caps.hw_caps & ATH9K_HW_CAP_5GHZ)
  		ath9k_init_band_txpower(sc, NL80211_BAND_5GHZ);
  
@@ -65,7 +65,7 @@
  }
  
  static const struct ieee80211_iface_limit if_limits[] = {
-@@ -948,6 +949,18 @@ static void ath9k_set_hw_capab(struct at
+@@ -950,6 +951,18 @@ static void ath9k_set_hw_capab(struct at
  	SET_IEEE80211_PERM_ADDR(hw, common->macaddr);
  }
  
@@ -84,7 +84,7 @@
  int ath9k_init_device(u16 devid, struct ath_softc *sc,
  		    const struct ath_bus_ops *bus_ops)
  {
-@@ -993,6 +1006,8 @@ int ath9k_init_device(u16 devid, struct
+@@ -995,6 +1008,8 @@ int ath9k_init_device(u16 devid, struct
  		ARRAY_SIZE(ath9k_tpt_blink));
  #endif
  
diff --git a/package/kernel/mac80211/patches/548-ath9k_enable_gpio_chip.patch b/package/kernel/mac80211/patches/548-ath9k_enable_gpio_chip.patch
index 1330dfe..666622d 100644
--- a/package/kernel/mac80211/patches/548-ath9k_enable_gpio_chip.patch
+++ b/package/kernel/mac80211/patches/548-ath9k_enable_gpio_chip.patch
@@ -18,7 +18,7 @@ Signed-off-by: Felix Fietkau <nbd@nbd.name>
  
  #include "common.h"
  #include "debug.h"
-@@ -973,6 +974,14 @@ struct ath_led {
+@@ -1001,6 +1002,14 @@ struct ath_led {
  	struct led_classdev cdev;
  };
  
@@ -33,7 +33,7 @@ Signed-off-by: Felix Fietkau <nbd@nbd.name>
  struct ath_softc {
  	struct ieee80211_hw *hw;
  	struct device *dev;
-@@ -1027,6 +1036,9 @@ struct ath_softc {
+@@ -1057,6 +1066,9 @@ struct ath_softc {
  #ifdef CPTCFG_MAC80211_LEDS
  	const char *led_default_trigger;
  	struct list_head leds;
diff --git a/package/kernel/mac80211/patches/549-ath9k_enable_gpio_buttons.patch b/package/kernel/mac80211/patches/549-ath9k_enable_gpio_buttons.patch
index f86b015..b8dd263 100644
--- a/package/kernel/mac80211/patches/549-ath9k_enable_gpio_buttons.patch
+++ b/package/kernel/mac80211/patches/549-ath9k_enable_gpio_buttons.patch
@@ -10,7 +10,7 @@ Signed-off-by: Felix Fietkau <nbd@nbd.name>
 ---
 --- a/drivers/net/wireless/ath/ath9k/ath9k.h
 +++ b/drivers/net/wireless/ath/ath9k/ath9k.h
-@@ -1038,6 +1038,7 @@ struct ath_softc {
+@@ -1068,6 +1068,7 @@ struct ath_softc {
  	struct list_head leds;
  #ifdef CONFIG_GPIOLIB
  	struct ath9k_gpio_chip *gpiochip;
diff --git a/package/kernel/mac80211/patches/554-ath9k-consistently-use-get_eeprom_rev-ah.patch b/package/kernel/mac80211/patches/554-ath9k-consistently-use-get_eeprom_rev-ah.patch
index 64e7046..86809fd 100644
--- a/package/kernel/mac80211/patches/554-ath9k-consistently-use-get_eeprom_rev-ah.patch
+++ b/package/kernel/mac80211/patches/554-ath9k-consistently-use-get_eeprom_rev-ah.patch
@@ -329,7 +329,7 @@ Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
  					       &ratesArray[0], cfgCtl,
 --- a/drivers/net/wireless/ath/ath9k/xmit.c
 +++ b/drivers/net/wireless/ath/ath9k/xmit.c
-@@ -1177,8 +1177,9 @@ static u8 ath_get_rate_txpower(struct at
+@@ -1236,8 +1236,9 @@ static u8 ath_get_rate_txpower(struct at
  		if (is_40) {
  			u8 power_ht40delta;
  			struct ar5416_eeprom_def *eep = &ah->eeprom.def;