--- /dev/null
+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;
projects / openwrt / staging / ynezz.git / commitdiff