This modifies the logic in ath_txq_schedule to account airtime consumed by each station and uses a deficit-based scheduler derived from FQ-CoDel to try to enforce airtime fairness. A debugfs entry controls whether TX airtime, RX airtime or both is accounted to the deficit on which the scheduler makes decisions.
Uses the ts->duration + retry-chain information to account for time spent transmitting to a station. The RX airtime is measured as the duration from first to last frame in an aggregate, using the rs_tstamp fields. Signed-off-by: Toke Høiland-Jørgensen <[email protected]> --- drivers/net/wireless/ath/ath9k/ath9k.h | 18 +++- drivers/net/wireless/ath/ath9k/channel.c | 12 ++- drivers/net/wireless/ath/ath9k/debug.c | 3 + drivers/net/wireless/ath/ath9k/debug.h | 29 ++++++ drivers/net/wireless/ath/ath9k/debug_sta.c | 46 ++++++++++ drivers/net/wireless/ath/ath9k/init.c | 1 + drivers/net/wireless/ath/ath9k/main.c | 6 +- drivers/net/wireless/ath/ath9k/recv.c | 60 +++++++++++++ drivers/net/wireless/ath/ath9k/xmit.c | 136 ++++++++++++++++++++--------- 9 files changed, 261 insertions(+), 50 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h index caeae10..e5a930c 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -261,9 +261,12 @@ struct ath_node { bool sleeping; bool no_ps_filter; + s64 airtime_deficit; + u32 airtime_rx_start; #ifdef CONFIG_ATH9K_STATION_STATISTICS struct ath_rx_rate_stats rx_rate_stats; + struct ath_airtime_stats airtime_stats; #endif u8 key_idx[4]; @@ -331,10 +334,15 @@ struct ath_rx { /* Channel Context */ /*******************/ +struct ath_acq { + struct list_head acq_new; + struct list_head acq_old; +}; + 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 */ @@ -573,6 +581,8 @@ 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); +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, @@ -959,6 +969,10 @@ void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs); #define ATH9K_NUM_CHANCTX 2 /* supports 2 operating channels */ +#define AIRTIME_USE_TX BIT(0) +#define AIRTIME_USE_RX BIT(1) +#define AIRTIME_ACTIVE(flags) (!!(flags & (AIRTIME_USE_TX|AIRTIME_USE_RX))) + struct ath_softc { struct ieee80211_hw *hw; struct device *dev; @@ -1001,6 +1015,8 @@ 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; diff --git a/drivers/net/wireless/ath/ath9k/channel.c b/drivers/net/wireless/ath/ath9k/channel.c index e56bafc..2594029 100644 --- a/drivers/net/wireless/ath/ath9k/channel.c +++ b/drivers/net/wireless/ath/ath9k/channel.c @@ -118,8 +118,10 @@ void ath_chanctx_init(struct ath_softc *sc) 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); + } } } @@ -1344,8 +1346,10 @@ void ath9k_offchannel_init(struct ath_softc *sc) 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); + } sc->offchannel.chan.offchannel = true; } diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c index c56e40f..413de3c 100644 --- a/drivers/net/wireless/ath/ath9k/debug.c +++ b/drivers/net/wireless/ath/ath9k/debug.c @@ -1411,5 +1411,8 @@ 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; } diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h index cd68c5f..bf1a540 100644 --- a/drivers/net/wireless/ath/ath9k/debug.h +++ b/drivers/net/wireless/ath/ath9k/debug.h @@ -223,6 +223,11 @@ 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 @@ -316,12 +321,36 @@ ath9k_debug_sync_cause(struct ath_softc *sc, u32 sync_cause) void ath_debug_rate_stats(struct ath_softc *sc, struct ath_rx_status *rs, struct sk_buff *skb); +void ath_debug_tx_airtime(struct ath_softc *sc, + struct ath_buf *bf, + struct ath_tx_status *ts); +void ath_debug_rx_airtime(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_tx_airtime(struct ath_softc *sc, + struct ath_buf *bf, + struct ath_tx_status *ts) +{ +} +static inline void ath_debug_rx_airtime(struct ath_softc *sc, + struct ath_rx_status *rs, + struct sk_buff *skb) +{ +} +static void ath_debug_airtime(struct ath_softc *sc, + struct ath_node *an, + u32 rx, u32 tx) +{ +} #endif /* CONFIG_ATH9K_STATION_STATISTICS */ #endif /* DEBUG_H */ diff --git a/drivers/net/wireless/ath/ath9k/debug_sta.c b/drivers/net/wireless/ath/ath9k/debug_sta.c index 0e7f6b5..e7f2ef2 100644 --- a/drivers/net/wireless/ath/ath9k/debug_sta.c +++ b/drivers/net/wireless/ath/ath9k/debug_sta.c @@ -245,6 +245,51 @@ static const struct file_operations fops_node_recv = { .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; + u32 len = 0, size = 128; + char *buf; + size_t retval; + + 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: %lld us\n", an->airtime_deficit); + + 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, @@ -254,4 +299,5 @@ void ath9k_sta_add_debugfs(struct ieee80211_hw *hw, 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); } diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c index 211736c..f4e9dd3 100644 --- a/drivers/net/wireless/ath/ath9k/init.c +++ b/drivers/net/wireless/ath/ath9k/init.c @@ -560,6 +560,7 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc, /* Will be cleared in ath9k_start() */ set_bit(ATH_OP_INVALID, &common->op_flags); + sc->airtime_flags = AIRTIME_USE_TX | AIRTIME_USE_RX; sc->sc_ah = ah; sc->dfs_detector = dfs_pattern_detector_init(common, NL80211_DFS_UNSET); diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index 6ab56e5..e13068b 100644 --- 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(struct ath_softc *sc, struct ath_txq *txq, 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: diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index 32160fc..a48667f 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -991,6 +991,65 @@ static void ath9k_apply_ampdu_details(struct ath_softc *sc, } } +static void ath_rx_count_airtime(struct ath_softc *sc, + struct ath_rx_status *rs, + struct sk_buff *skb) +{ + struct ath_node *an; + 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; + u32 airtime = 0; + + 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; + + if (rs->rs_isaggr && rs->rs_firstaggr) { + an->airtime_rx_start = rs->rs_tstamp; + } else if (rs->rs_isaggr && !rs->rs_moreaggr && an->airtime_rx_start) { + airtime = rs->rs_tstamp - an->airtime_rx_start; + } else if (!rs->rs_isaggr) { + an->airtime_rx_start = 0; + + 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, rs->rs_datalen, + 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, + rs->rs_datalen, rxs->rate_idx, is_sp); + } + } + + if (!!(sc->airtime_flags & AIRTIME_USE_RX)) + an->airtime_deficit -= airtime; + 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 +1196,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp) 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)) diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index cdc8684..ef0a4a1 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -108,16 +108,19 @@ void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq) static void ath_tx_queue_tid(struct ath_softc *sc, struct ath_txq *txq, 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; if (!ctx) return; - list = &ctx->acq[TID_TO_WME_AC(tid->tidno)]; + + acq = &ctx->acq[TID_TO_WME_AC(tid->tidno)]; + tid_list = AIRTIME_ACTIVE(sc->airtime_flags) ? &acq->acq_new : &acq->acq_old; if (list_empty(&tid->list)) - list_add_tail(&tid->list, list); + list_add_tail(&tid->list, tid_list); } void ath9k_wake_tx_queue(struct ieee80211_hw *hw, struct ieee80211_txq *swq) @@ -722,6 +725,48 @@ static bool bf_is_ampdu_not_probing(struct ath_buf *bf) return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE); } +static void ath_tx_count_airtime(struct ath_softc *sc, + struct ath_buf *bf, + struct ath_tx_status *ts) +{ + struct ath_node *an; + 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)) + an->airtime_deficit -= airtime; + 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) @@ -739,6 +784,8 @@ static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq, ts->duration = ath9k_hw_get_duration(sc->sc_ah, bf->bf_desc, ts->ts_rateindex); + ath_tx_count_airtime(sc, bf, ts); + if (!bf_isampdu(bf)) { if (!flush) { info = IEEE80211_SKB_CB(bf->bf_mpdu); @@ -751,6 +798,7 @@ static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq, } else ath_tx_complete_aggr(sc, txq, bf, bf_head, ts, txok); + if (!flush) ath_txq_schedule(sc, txq); } @@ -1090,8 +1138,8 @@ ath_tx_form_aggr(struct ath_softc *sc, struct ath_txq *txq, * 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; @@ -1490,7 +1538,7 @@ ath_tx_form_burst(struct ath_softc *sc, struct ath_txq *txq, } 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; @@ -1512,7 +1560,6 @@ static bool ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq, aggr = !!(tx_info->flags & IEEE80211_TX_CTL_AMPDU); if ((aggr && txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) || (!aggr && txq->axq_depth >= ATH_NON_AGGR_MIN_QDEPTH)) { - *stop = true; return false; } @@ -1984,9 +2031,10 @@ void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq) 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; @@ -1995,48 +2043,50 @@ void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq) return; spin_lock_bh(&sc->chan_lock); - tid_list = &sc->cur_chan->acq[txq->mac80211_qnum]; + acq = &sc->cur_chan->acq[txq->mac80211_qnum]; - if (list_empty(tid_list)) { - spin_unlock_bh(&sc->chan_lock); - return; - } + if (sc->cur_chan->stopped) + goto out; rcu_read_lock(); +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); - 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 (ath_tx_sched_aggr(sc, txq, tid, &stop)) - sent = true; - - /* - * 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 <= 0) { + tid->an->airtime_deficit += 300; + list_move_tail(&tid->list, &acq->acq_old); + goto begin; + } - if (stop) - break; + if (!ath_tid_has_buffered(tid)) { + 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); + goto begin; + } - if (tid == last_tid) { - if (!sent) - break; - sent = false; - last_tid = list_entry(tid_list->prev, - struct ath_atx_tid, list); - } + /* If a station succeeds in queueing something, immediately restart the + * loop. This makes sure the queues are shuffled if the station now has + * no more packets queued, and also ensures we keep the hardware queues + * full. + * + * If we dequeued from a new queue, shuffle the queues, to prevent it + * from hogging too much airtime. */ + if(ath_tx_sched_aggr(sc, txq, tid)) { + if (!active || ((tid_list == &acq->acq_new) && !list_empty(&acq->acq_old))) + list_move_tail(&tid->list, &acq->acq_old); + goto begin; } +out: rcu_read_unlock(); spin_unlock_bh(&sc->chan_lock); } @@ -2931,6 +2981,8 @@ void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an) struct ath_atx_tid *tid; int tidno, acno; + an->airtime_deficit = 300; + for (tidno = 0; tidno < IEEE80211_NUM_TIDS; tidno++) { -- 2.8.3 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
