@@ -6571,9 +6571,6 @@ static inline void ieee80211_txq_schedule_end(struct ieee80211_hw *hw, u8 ac)
{
}
-void __ieee80211_schedule_txq(struct ieee80211_hw *hw,
- struct ieee80211_txq *txq, bool force);
-
/**
* ieee80211_schedule_txq - schedule a TXQ for transmission
*
@@ -6586,11 +6583,7 @@ void __ieee80211_schedule_txq(struct ieee80211_hw *hw,
* The driver may call this function if it has buffered packets for
* this TXQ internally.
*/
-static inline void
-ieee80211_schedule_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq)
-{
- __ieee80211_schedule_txq(hw, txq, true);
-}
+void ieee80211_schedule_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq);
/**
* ieee80211_return_txq - return a TXQ previously acquired by ieee80211_next_txq()
@@ -6602,12 +6595,8 @@ ieee80211_schedule_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq)
* The driver may set force=true if it has buffered packets for this TXQ
* internally.
*/
-static inline void
-ieee80211_return_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq,
- bool force)
-{
- __ieee80211_schedule_txq(hw, txq, force);
-}
+void ieee80211_return_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq,
+ bool force);
/**
* ieee80211_txq_may_transmit - check whether TXQ is allowed to transmit
@@ -1449,7 +1449,8 @@ static int sta_apply_parameters(struct ieee80211_local *local,
int ret = 0;
struct ieee80211_supported_band *sband;
struct ieee80211_sub_if_data *sdata = sta->sdata;
- u32 mask, set;
+ u32 mask, set, tid, ac;
+ struct txq_info *txqi;
sband = ieee80211_get_sband(sdata);
if (!sband)
@@ -1628,8 +1629,29 @@ static int sta_apply_parameters(struct ieee80211_local *local,
if (ieee80211_vif_is_mesh(&sdata->vif))
sta_apply_mesh_params(local, sta, params);
- if (params->airtime_weight)
- sta->airtime_weight = params->airtime_weight;
+ if (params->airtime_weight) {
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ struct airtime_sched_info *air_sched = &local->airtime[ac];
+ struct airtime_info *air_info = &sta->airtime[ac];
+
+ spin_lock_bh(&air_sched->lock);
+ for (tid = 0; tid < IEEE80211_NUM_TIDS + 1; tid++) {
+ if (air_info->weight == params->airtime_weight ||
+ !sta->sta.txq[tid] ||
+ ac != ieee80211_ac_from_tid(tid))
+ continue;
+
+ airtime_weight_set(air_info, params->airtime_weight);
+
+ txqi = to_txq_info(sta->sta.txq[tid]);
+ if (RB_EMPTY_NODE(&txqi->schedule_order))
+ continue;
+
+ ieee80211_update_airtime_weight(local, air_sched, 0, true);
+ }
+ spin_unlock_bh(&air_sched->lock);
+ }
+ }
/* set the STA state after all sta info from usermode has been set */
if (test_sta_flag(sta, WLAN_STA_TDLS_PEER) ||
@@ -216,14 +216,14 @@ static ssize_t aql_txq_limit_read(struct file *file,
"VI %u %u\n"
"BE %u %u\n"
"BK %u %u\n",
- local->aql_txq_limit_low[IEEE80211_AC_VO],
- local->aql_txq_limit_high[IEEE80211_AC_VO],
- local->aql_txq_limit_low[IEEE80211_AC_VI],
- local->aql_txq_limit_high[IEEE80211_AC_VI],
- local->aql_txq_limit_low[IEEE80211_AC_BE],
- local->aql_txq_limit_high[IEEE80211_AC_BE],
- local->aql_txq_limit_low[IEEE80211_AC_BK],
- local->aql_txq_limit_high[IEEE80211_AC_BK]);
+ local->airtime[IEEE80211_AC_VO].aql_txq_limit_low,
+ local->airtime[IEEE80211_AC_VO].aql_txq_limit_high,
+ local->airtime[IEEE80211_AC_VI].aql_txq_limit_low,
+ local->airtime[IEEE80211_AC_VI].aql_txq_limit_high,
+ local->airtime[IEEE80211_AC_BE].aql_txq_limit_low,
+ local->airtime[IEEE80211_AC_BE].aql_txq_limit_high,
+ local->airtime[IEEE80211_AC_BK].aql_txq_limit_low,
+ local->airtime[IEEE80211_AC_BK].aql_txq_limit_high);
return simple_read_from_buffer(user_buf, count, ppos,
buf, len);
}
@@ -255,11 +255,11 @@ static ssize_t aql_txq_limit_write(struct file *file,
if (ac >= IEEE80211_NUM_ACS)
return -EINVAL;
- q_limit_low_old = local->aql_txq_limit_low[ac];
- q_limit_high_old = local->aql_txq_limit_high[ac];
+ q_limit_low_old = local->airtime[ac].aql_txq_limit_low;
+ q_limit_high_old = local->airtime[ac].aql_txq_limit_high;
- local->aql_txq_limit_low[ac] = q_limit_low;
- local->aql_txq_limit_high[ac] = q_limit_high;
+ local->airtime[ac].aql_txq_limit_low = q_limit_low;
+ local->airtime[ac].aql_txq_limit_high = q_limit_high;
mutex_lock(&local->sta_mtx);
list_for_each_entry(sta, &local->sta_list, list) {
@@ -382,6 +382,46 @@ static const struct file_operations force_tx_status_ops = {
.llseek = default_llseek,
};
+static ssize_t airtime_read(struct file *file,
+ char __user *user_buf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct ieee80211_local *local = file->private_data;
+ char buf[200];
+ u64 v_t[IEEE80211_NUM_ACS];
+ u64 wt[IEEE80211_NUM_ACS];
+ int len = 0, ac;
+
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ spin_lock_bh(&local->airtime[ac].lock);
+ v_t[ac] = local->airtime[ac].v_t;
+ wt[ac] = local->airtime[ac].weight_sum;
+ spin_unlock_bh(&local->airtime[ac].lock);
+ }
+ len = scnprintf(buf, sizeof(buf),
+ "\tVO VI BE BK\n"
+ "Virt-t\t%-10llu %-10llu %-10llu %-10llu\n"
+ "Weight\t%-10llu %-10llu %-10llu %-10llu\n",
+ v_t[0],
+ v_t[1],
+ v_t[2],
+ v_t[3],
+ wt[0],
+ wt[1],
+ wt[2],
+ wt[3]);
+
+ return simple_read_from_buffer(user_buf, count, ppos,
+ buf, len);
+}
+
+static const struct file_operations airtime_ops = {
+ .read = airtime_read,
+ .open = simple_open,
+ .llseek = default_llseek,
+};
+
#ifdef CONFIG_PM
static ssize_t reset_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
@@ -625,7 +665,11 @@ void debugfs_hw_add(struct ieee80211_local *local)
if (local->ops->wake_tx_queue)
DEBUGFS_ADD_MODE(aqm, 0600);
- DEBUGFS_ADD_MODE(airtime_flags, 0600);
+ if (wiphy_ext_feature_isset(local->hw.wiphy,
+ NL80211_EXT_FEATURE_AIRTIME_FAIRNESS)) {
+ DEBUGFS_ADD_MODE(airtime, 0600);
+ DEBUGFS_ADD_MODE(airtime_flags, 0600);
+ }
DEBUGFS_ADD(aql_txq_limit);
debugfs_create_u32("aql_threshold", 0600,
@@ -513,6 +513,34 @@ static ssize_t ieee80211_if_fmt_aqm(
}
IEEE80211_IF_FILE_R(aqm);
+static ssize_t ieee80211_if_fmt_airtime(
+ const struct ieee80211_sub_if_data *sdata, char *buf, int buflen)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_txq *txq = sdata->vif.txq;
+ struct airtime_info *air_info;
+ int len;
+
+ if (!txq)
+ return 0;
+
+ spin_lock_bh(&local->airtime[txq->ac].lock);
+ air_info = to_airtime_info(txq);
+ len = scnprintf(buf,
+ buflen,
+ "RX: %llu us\nTX: %llu us\nWeight: %u\n"
+ "Virt-T: %lld us\n",
+ air_info->rx_airtime,
+ air_info->tx_airtime,
+ air_info->weight,
+ air_info->v_t);
+ spin_unlock_bh(&local->airtime[txq->ac].lock);
+
+ return len;
+}
+
+IEEE80211_IF_FILE_R(airtime);
+
IEEE80211_IF_FILE(multicast_to_unicast, u.ap.multicast_to_unicast, HEX);
/* IBSS attributes */
@@ -658,8 +686,10 @@ static void add_common_files(struct ieee80211_sub_if_data *sdata)
if (sdata->local->ops->wake_tx_queue &&
sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
- sdata->vif.type != NL80211_IFTYPE_NAN)
+ sdata->vif.type != NL80211_IFTYPE_NAN) {
DEBUGFS_ADD(aqm);
+ DEBUGFS_ADD(airtime);
+ }
}
static void add_sta_files(struct ieee80211_sub_if_data *sdata)
@@ -202,7 +202,7 @@ static ssize_t sta_airtime_read(struct file *file, char __user *userbuf,
size_t bufsz = 400;
char *buf = kzalloc(bufsz, GFP_KERNEL), *p = buf;
u64 rx_airtime = 0, tx_airtime = 0;
- s64 deficit[IEEE80211_NUM_ACS];
+ u64 v_t[IEEE80211_NUM_ACS];
ssize_t rv;
int ac;
@@ -210,18 +210,18 @@ static ssize_t sta_airtime_read(struct file *file, char __user *userbuf,
return -ENOMEM;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
- spin_lock_bh(&local->active_txq_lock[ac]);
+ spin_lock_bh(&local->airtime[ac].lock);
rx_airtime += sta->airtime[ac].rx_airtime;
tx_airtime += sta->airtime[ac].tx_airtime;
- deficit[ac] = sta->airtime[ac].deficit;
- spin_unlock_bh(&local->active_txq_lock[ac]);
+ v_t[ac] = sta->airtime[ac].v_t;
+ spin_unlock_bh(&local->airtime[ac].lock);
}
p += scnprintf(p, bufsz + buf - p,
"RX: %llu us\nTX: %llu us\nWeight: %u\n"
- "Deficit: VO: %lld us VI: %lld us BE: %lld us BK: %lld us\n",
- rx_airtime, tx_airtime, sta->airtime_weight,
- deficit[0], deficit[1], deficit[2], deficit[3]);
+ "Virt-T: VO: %lld us VI: %lld us BE: %lld us BK: %lld us\n",
+ rx_airtime, tx_airtime, sta->airtime[0].weight,
+ v_t[0], v_t[1], v_t[2], v_t[3]);
rv = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
kfree(buf);
@@ -236,11 +236,11 @@ static ssize_t sta_airtime_write(struct file *file, const char __user *userbuf,
int ac;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
- spin_lock_bh(&local->active_txq_lock[ac]);
+ spin_lock_bh(&local->airtime[ac].lock);
sta->airtime[ac].rx_airtime = 0;
sta->airtime[ac].tx_airtime = 0;
- sta->airtime[ac].deficit = sta->airtime_weight;
- spin_unlock_bh(&local->active_txq_lock[ac]);
+ sta->airtime[ac].v_t = 0;
+ spin_unlock_bh(&local->airtime[ac].lock);
}
return count;
@@ -263,10 +263,10 @@ static ssize_t sta_aql_read(struct file *file, char __user *userbuf,
return -ENOMEM;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
- spin_lock_bh(&local->active_txq_lock[ac]);
+ spin_lock_bh(&local->airtime[ac].lock);
q_limit_l[ac] = sta->airtime[ac].aql_limit_low;
q_limit_h[ac] = sta->airtime[ac].aql_limit_high;
- spin_unlock_bh(&local->active_txq_lock[ac]);
+ spin_unlock_bh(&local->airtime[ac].lock);
q_depth[ac] = atomic_read(&sta->airtime[ac].aql_tx_pending);
}
@@ -851,8 +851,7 @@ struct txq_info {
struct codel_vars def_cvars;
struct codel_stats cstats;
struct sk_buff_head frags;
- struct list_head schedule_order;
- u16 schedule_round;
+ struct rb_node schedule_order;
unsigned long flags;
/* keep last! */
@@ -931,6 +930,8 @@ struct ieee80211_sub_if_data {
struct ieee80211_tx_queue_params tx_conf[IEEE80211_NUM_ACS];
struct mac80211_qos_map __rcu *qos_map;
+ struct airtime_info airtime[IEEE80211_NUM_ACS];
+
struct work_struct csa_finalize_work;
bool csa_block_tx; /* write-protected by sdata_lock and local->mtx */
struct cfg80211_chan_def csa_chandef;
@@ -1143,6 +1144,38 @@ enum mac80211_scan_state {
SCAN_ABORT,
};
+/**
+ * struct airtime_sched_info - state used for airtime scheduling and AQL
+ *
+ * @lock: spinlock that protects all the fields in this struct
+ * @active_txqs: rbtree of currently backlogged queues, sorted by virtual time
+ * @schedule_pos: the current position maintained while a driver walks the tree
+ * with ieee80211_next_txq()
+ * @active_list: list of struct airtime_info structs that were active within
+ * the last AIRTIME_ACTIVE_DURATION (100 ms), used to compute weight_sum
+ * @last_weight_update: used for rate limiting walking active_list
+ * @last_schedule_time: tracks the last time a transmission was scheduled; used
+ * for catching up v_t if no stations are eligible for transmission.
+ * @v_t: global virtual time; queues with v_t < this are eligible for transmission
+ * @weight_sum: total sum of all active stations used for dividing airtime
+ * @weight_sum_reciprocal: reciprocal of weight_sum (to avoid divisions in fast
+ * path - see comment above IEEE80211_RECIPROCAL_DIVISOR_64)
+ * @aql_txq_limit_low: AQL limit when total outstanding airtime is < IEEE80211_AQL_THRESHOLD
+ * @aql_txq_limit_high: AQL limit when total outstanding airtime is > IEEE80211_AQL_THRESHOLD
+ */
+struct airtime_sched_info {
+ spinlock_t lock;
+ struct rb_root_cached active_txqs;
+ struct rb_node *schedule_pos;
+ struct list_head active_list;
+ u64 last_weight_update;
+ u64 last_schedule_activity;
+ u64 v_t;
+ u64 weight_sum;
+ u64 weight_sum_reciprocal;
+ u32 aql_txq_limit_low;
+ u32 aql_txq_limit_high;
+};
DECLARE_STATIC_KEY_FALSE(aql_disable);
struct ieee80211_local {
@@ -1156,13 +1189,8 @@ struct ieee80211_local {
struct codel_params cparams;
/* protects active_txqs and txqi->schedule_order */
- spinlock_t active_txq_lock[IEEE80211_NUM_ACS];
- struct list_head active_txqs[IEEE80211_NUM_ACS];
- u16 schedule_round[IEEE80211_NUM_ACS];
-
+ struct airtime_sched_info airtime[IEEE80211_NUM_ACS];
u16 airtime_flags;
- u32 aql_txq_limit_low[IEEE80211_NUM_ACS];
- u32 aql_txq_limit_high[IEEE80211_NUM_ACS];
u32 aql_threshold;
atomic_t aql_total_pending_airtime;
@@ -1580,6 +1608,125 @@ static inline bool txq_has_queue(struct ieee80211_txq *txq)
return !(skb_queue_empty(&txqi->frags) && !txqi->tin.backlog_packets);
}
+static inline struct airtime_info *to_airtime_info(struct ieee80211_txq *txq)
+{
+ struct ieee80211_sub_if_data *sdata;
+ struct sta_info *sta;
+
+ if (txq->sta) {
+ sta = container_of(txq->sta, struct sta_info, sta);
+ return &sta->airtime[txq->ac];
+ }
+
+ sdata = vif_to_sdata(txq->vif);
+ return &sdata->airtime[txq->ac];
+}
+
+/* To avoid divisions in the fast path, we keep pre-computed reciprocals for
+ * airtime weight calculations. There are two different weights to keep track
+ * of: The per-station weight and the sum of weights per phy.
+ *
+ * For the per-station weights (kept in airtime_info below), we use 32-bit
+ * reciprocals with a devisor of 2^19. This lets us keep the multiplications and
+ * divisions for the station weights as 32-bit operations at the cost of a bit
+ * of rounding error for high weights; but the choice of divisor keeps rounding
+ * errors <10% for weights <2^15, assuming no more than 8ms of airtime is
+ * reported at a time.
+ *
+ * For the per-phy sum of weights the values can get higher, so we use 64-bit
+ * operations for those with a 32-bit divisor, which should avoid any
+ * significant rounding errors.
+ */
+#define IEEE80211_RECIPROCAL_DIVISOR_64 0x100000000ULL
+#define IEEE80211_RECIPROCAL_SHIFT_64 32
+#define IEEE80211_RECIPROCAL_DIVISOR_32 0x80000U
+#define IEEE80211_RECIPROCAL_SHIFT_32 19
+
+static inline void airtime_weight_set(struct airtime_info *air_info, u16 weight)
+{
+ if (air_info->weight == weight)
+ return;
+
+ air_info->weight = weight;
+ if (weight) {
+ air_info->weight_reciprocal =
+ IEEE80211_RECIPROCAL_DIVISOR_32 / weight;
+ } else {
+ air_info->weight_reciprocal = 0;
+ }
+}
+
+static inline void airtime_weight_sum_set(struct airtime_sched_info *air_sched,
+ int weight_sum)
+{
+ if (air_sched->weight_sum == weight_sum)
+ return;
+
+ air_sched->weight_sum = weight_sum;
+ if (air_sched->weight_sum) {
+ air_sched->weight_sum_reciprocal = IEEE80211_RECIPROCAL_DIVISOR_64;
+ do_div(air_sched->weight_sum_reciprocal, air_sched->weight_sum);
+ } else {
+ air_sched->weight_sum_reciprocal = 0;
+ }
+}
+
+/* A problem when trying to enforce airtime fairness is that we want to divide
+ * the airtime between the currently *active* stations. However, basing this on
+ * the instantaneous queue state of stations doesn't work, as queues tend to
+ * oscillate very quickly between empty and occupied, leading to the scheduler
+ * thinking only a single station is active when deciding whether to allow
+ * transmission (and thus not throttling correctly).
+ *
+ * To fix this we use a timer-based notion of activity: a station is considered
+ * active if it has been scheduled within the last 100 ms; we keep a separate
+ * list of all the stations considered active in this manner, and lazily update
+ * the total weight of active stations from this list (filtering the stations in
+ * the list by their 'last active' time).
+ *
+ * We add one additional safeguard to guard against stations that manage to get
+ * scheduled every 100 ms but don't transmit a lot of data, and thus don't use
+ * up any airtime. Such stations would be able to get priority for an extended
+ * period of time if they do start transmitting at full capacity again, and so
+ * we add an explicit maximum for how far behind a station is allowed to fall in
+ * the virtual airtime domain. This limit is set to a relatively high value of
+ * 20 ms because the main mechanism for catching up idle stations is the active
+ * state as described above; i.e., the hard limit should only be hit in
+ * pathological cases.
+ */
+#define AIRTIME_ACTIVE_DURATION (100 * NSEC_PER_MSEC)
+#define AIRTIME_MAX_BEHIND 20000 /* 20 ms */
+
+static inline bool airtime_is_active(struct airtime_info *air_info, u64 now)
+{
+ return air_info->last_scheduled >= now - AIRTIME_ACTIVE_DURATION;
+}
+
+static inline void airtime_set_active(struct airtime_sched_info *air_sched,
+ struct airtime_info *air_info, u64 now)
+{
+ air_info->last_scheduled = now;
+ air_sched->last_schedule_activity = now;
+ list_move_tail(&air_info->list, &air_sched->active_list);
+}
+
+static inline bool airtime_catchup_v_t(struct airtime_sched_info *air_sched,
+ u64 v_t, u64 now)
+{
+ air_sched->v_t = v_t;
+ return true;
+}
+
+static inline void init_airtime_info(struct airtime_info *air_info,
+ struct airtime_sched_info *air_sched)
+{
+ atomic_set(&air_info->aql_tx_pending, 0);
+ air_info->aql_limit_low = air_sched->aql_txq_limit_low;
+ air_info->aql_limit_high = air_sched->aql_txq_limit_high;
+ airtime_weight_set(air_info, IEEE80211_DEFAULT_AIRTIME_WEIGHT);
+ INIT_LIST_HEAD(&air_info->list);
+}
+
static inline int ieee80211_bssid_match(const u8 *raddr, const u8 *addr)
{
return ether_addr_equal(raddr, addr) ||
@@ -1822,6 +1969,14 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
u64 *cookie);
int ieee80211_probe_mesh_link(struct wiphy *wiphy, struct net_device *dev,
const u8 *buf, size_t len);
+void ieee80211_resort_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq);
+void ieee80211_unschedule_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq,
+ bool purge);
+void ieee80211_update_airtime_weight(struct ieee80211_local *local,
+ struct airtime_sched_info *air_sched,
+ u64 now, bool force);
/* HT */
void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
@@ -1963,6 +1963,9 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
}
}
+ for (i = 0; i < IEEE80211_NUM_ACS; i++)
+ init_airtime_info(&sdata->airtime[i], &local->airtime[i]);
+
ieee80211_set_default_queues(sdata);
sdata->ap_power_level = IEEE80211_UNSET_POWER_LEVEL;
@@ -701,10 +701,13 @@ struct ieee80211_hw *ieee80211_alloc_hw_nm(size_t priv_data_len,
spin_lock_init(&local->queue_stop_reason_lock);
for (i = 0; i < IEEE80211_NUM_ACS; i++) {
- INIT_LIST_HEAD(&local->active_txqs[i]);
- spin_lock_init(&local->active_txq_lock[i]);
- local->aql_txq_limit_low[i] = IEEE80211_DEFAULT_AQL_TXQ_LIMIT_L;
- local->aql_txq_limit_high[i] =
+ struct airtime_sched_info *air_sched = &local->airtime[i];
+
+ air_sched->active_txqs = RB_ROOT_CACHED;
+ INIT_LIST_HEAD(&air_sched->active_list);
+ spin_lock_init(&air_sched->lock);
+ air_sched->aql_txq_limit_low = IEEE80211_DEFAULT_AQL_TXQ_LIMIT_L;
+ air_sched->aql_txq_limit_high =
IEEE80211_DEFAULT_AQL_TXQ_LIMIT_H;
}
@@ -1562,12 +1562,8 @@ static void sta_ps_start(struct sta_info *sta)
for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
struct ieee80211_txq *txq = sta->sta.txq[tid];
- struct txq_info *txqi = to_txq_info(txq);
- spin_lock(&local->active_txq_lock[txq->ac]);
- if (!list_empty(&txqi->schedule_order))
- list_del_init(&txqi->schedule_order);
- spin_unlock(&local->active_txq_lock[txq->ac]);
+ ieee80211_unschedule_txq(&local->hw, txq, false);
if (txq_has_queue(txq))
set_bit(tid, &sta->txq_buffered_tids);
@@ -423,15 +423,11 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
if (sta_prepare_rate_control(local, sta, gfp))
goto free_txq;
- sta->airtime_weight = IEEE80211_DEFAULT_AIRTIME_WEIGHT;
for (i = 0; i < IEEE80211_NUM_ACS; i++) {
skb_queue_head_init(&sta->ps_tx_buf[i]);
skb_queue_head_init(&sta->tx_filtered[i]);
- sta->airtime[i].deficit = sta->airtime_weight;
- atomic_set(&sta->airtime[i].aql_tx_pending, 0);
- sta->airtime[i].aql_limit_low = local->aql_txq_limit_low[i];
- sta->airtime[i].aql_limit_high = local->aql_txq_limit_high[i];
+ init_airtime_info(&sta->airtime[i], &local->airtime[i]);
}
for (i = 0; i < IEEE80211_NUM_TIDS; i++)
@@ -1893,24 +1889,59 @@ void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
}
EXPORT_SYMBOL(ieee80211_sta_set_buffered);
-void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
- u32 tx_airtime, u32 rx_airtime)
+void ieee80211_register_airtime(struct ieee80211_txq *txq,
+ u32 tx_airtime, u32 rx_airtime)
{
- struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
- struct ieee80211_local *local = sta->sdata->local;
- u8 ac = ieee80211_ac_from_tid(tid);
+ struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);
+ struct ieee80211_local *local = sdata->local;
+ u64 weight_sum, weight_sum_reciprocal;
+ struct airtime_sched_info *air_sched;
+ struct airtime_info *air_info;
u32 airtime = 0;
- if (sta->local->airtime_flags & AIRTIME_USE_TX)
+ air_sched = &local->airtime[txq->ac];
+ air_info = to_airtime_info(txq);
+
+ if (local->airtime_flags & AIRTIME_USE_TX)
airtime += tx_airtime;
- if (sta->local->airtime_flags & AIRTIME_USE_RX)
+ if (local->airtime_flags & AIRTIME_USE_RX)
airtime += rx_airtime;
- spin_lock_bh(&local->active_txq_lock[ac]);
- sta->airtime[ac].tx_airtime += tx_airtime;
- sta->airtime[ac].rx_airtime += rx_airtime;
- sta->airtime[ac].deficit -= airtime;
- spin_unlock_bh(&local->active_txq_lock[ac]);
+ /* Weights scale so the unit weight is 256 */
+ airtime <<= 8;
+
+ spin_lock_bh(&air_sched->lock);
+
+ air_info->tx_airtime += tx_airtime;
+ air_info->rx_airtime += rx_airtime;
+
+ if (air_sched->weight_sum) {
+ weight_sum = air_sched->weight_sum;
+ weight_sum_reciprocal = air_sched->weight_sum_reciprocal;
+ } else {
+ weight_sum = air_info->weight;
+ weight_sum_reciprocal = air_info->weight_reciprocal;
+ }
+
+ /* Round the calculation of global vt */
+ air_sched->v_t += (u64)((airtime + (weight_sum >> 1)) *
+ weight_sum_reciprocal) >> IEEE80211_RECIPROCAL_SHIFT_64;
+ air_info->v_t += (u32)((airtime + (air_info->weight >> 1)) *
+ air_info->weight_reciprocal) >> IEEE80211_RECIPROCAL_SHIFT_32;
+ ieee80211_resort_txq(&local->hw, txq);
+
+ spin_unlock_bh(&air_sched->lock);
+}
+
+void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
+ u32 tx_airtime, u32 rx_airtime)
+{
+ struct ieee80211_txq *txq = pubsta->txq[tid];
+
+ if (!txq)
+ return;
+
+ ieee80211_register_airtime(txq, tx_airtime, rx_airtime);
}
EXPORT_SYMBOL(ieee80211_sta_register_airtime);
@@ -2359,7 +2390,7 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
}
if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT))) {
- sinfo->airtime_weight = sta->airtime_weight;
+ sinfo->airtime_weight = sta->airtime[0].weight;
sinfo->filled |= BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT);
}
@@ -135,18 +135,25 @@ enum ieee80211_agg_stop_reason {
#define AIRTIME_USE_TX BIT(0)
#define AIRTIME_USE_RX BIT(1)
+
struct airtime_info {
u64 rx_airtime;
u64 tx_airtime;
- s64 deficit;
+ u64 v_t;
+ u64 last_scheduled;
+ struct list_head list;
atomic_t aql_tx_pending; /* Estimated airtime for frames pending */
u32 aql_limit_low;
u32 aql_limit_high;
+ u32 weight_reciprocal;
+ u16 weight;
};
void ieee80211_sta_update_pending_airtime(struct ieee80211_local *local,
struct sta_info *sta, u8 ac,
u16 tx_airtime, bool tx_completed);
+void ieee80211_register_airtime(struct ieee80211_txq *txq,
+ u32 tx_airtime, u32 rx_airtime);
struct sta_info;
@@ -487,7 +494,6 @@ struct ieee80211_sta_rx_stats {
* @tid_seq: per-TID sequence numbers for sending to this STA
* @airtime: per-AC struct airtime_info describing airtime statistics for this
* station
- * @airtime_weight: station weight for airtime fairness calculation purposes
* @ampdu_mlme: A-MPDU state machine state
* @mesh: mesh STA information
* @debugfs_dir: debug filesystem directory dentry
@@ -617,7 +623,6 @@ struct sta_info {
u16 tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1];
struct airtime_info airtime[IEEE80211_NUM_ACS];
- u16 airtime_weight;
/*
* Aggregation information, locked with lock.
@@ -970,6 +970,24 @@ static void __ieee80211_tx_status(struct ieee80211_hw *hw,
if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
ieee80211_frame_acked(sta, skb);
+ } else if (wiphy_ext_feature_isset(local->hw.wiphy,
+ NL80211_EXT_FEATURE_AIRTIME_FAIRNESS)) {
+ struct ieee80211_sub_if_data *sdata;
+ struct ieee80211_txq *txq;
+ u32 airtime;
+
+ /* Account airtime to multicast queue */
+ sdata = ieee80211_sdata_from_skb(local, skb);
+
+ if (sdata && (txq = sdata->vif.txq)) {
+ airtime = info->status.tx_time ?:
+ ieee80211_calc_expected_tx_airtime(hw,
+ &sdata->vif,
+ NULL,
+ skb->len, false);
+
+ ieee80211_register_airtime(txq, airtime, 0);
+ }
}
/* SNMP counters
@@ -18,6 +18,7 @@
#include <linux/bitmap.h>
#include <linux/rcupdate.h>
#include <linux/export.h>
+#include <linux/timekeeping.h>
#include <net/net_namespace.h>
#include <net/ieee80211_radiotap.h>
#include <net/cfg80211.h>
@@ -1447,7 +1448,7 @@ 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);
+ RB_CLEAR_NODE(&txqi->schedule_order);
txqi->txq.vif = &sdata->vif;
@@ -1491,9 +1492,7 @@ void ieee80211_txq_purge(struct ieee80211_local *local,
ieee80211_purge_tx_queue(&local->hw, &txqi->frags);
spin_unlock_bh(&fq->lock);
- spin_lock_bh(&local->active_txq_lock[txqi->txq.ac]);
- list_del_init(&txqi->schedule_order);
- spin_unlock_bh(&local->active_txq_lock[txqi->txq.ac]);
+ ieee80211_unschedule_txq(&local->hw, &txqi->txq, true);
}
void ieee80211_txq_set_params(struct ieee80211_local *local)
@@ -3744,102 +3743,254 @@ EXPORT_SYMBOL(ieee80211_tx_dequeue);
struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw, u8 ac)
{
struct ieee80211_local *local = hw_to_local(hw);
+ struct airtime_sched_info *air_sched;
+ u64 now = ktime_get_boottime_ns();
struct ieee80211_txq *ret = NULL;
- struct txq_info *txqi = NULL, *head = NULL;
- bool found_eligible_txq = false;
+ struct airtime_info *air_info;
+ struct txq_info *txqi = NULL;
+ struct rb_node *node;
+ bool first = false;
- spin_lock_bh(&local->active_txq_lock[ac]);
+ air_sched = &local->airtime[ac];
+ spin_lock_bh(&air_sched->lock);
- begin:
- txqi = list_first_entry_or_null(&local->active_txqs[ac],
- struct txq_info,
- schedule_order);
- if (!txqi)
+ node = air_sched->schedule_pos;
+
+begin:
+ if (!node) {
+ node = rb_first_cached(&air_sched->active_txqs);
+ first = true;
+ } else {
+ node = rb_next(node);
+ }
+
+ if (!node)
goto out;
- if (txqi == head) {
- if (!found_eligible_txq)
- goto out;
- else
- found_eligible_txq = false;
+ txqi = container_of(node, struct txq_info, schedule_order);
+ air_info = to_airtime_info(&txqi->txq);
+
+ if (air_info->v_t > air_sched->v_t &&
+ (!first || !airtime_catchup_v_t(air_sched, air_info->v_t, now)))
+ goto out;
+
+ if (!ieee80211_txq_airtime_check(hw, &txqi->txq)) {
+ first = false;
+ goto begin;
}
- if (!head)
- head = txqi;
+ air_sched->schedule_pos = node;
+ air_sched->last_schedule_activity = now;
+ ret = &txqi->txq;
+out:
+ spin_unlock_bh(&air_sched->lock);
+ return ret;
+}
+EXPORT_SYMBOL(ieee80211_next_txq);
- if (txqi->txq.sta) {
- struct sta_info *sta = container_of(txqi->txq.sta,
- struct sta_info, sta);
- bool aql_check = ieee80211_txq_airtime_check(hw, &txqi->txq);
- s64 deficit = sta->airtime[txqi->txq.ac].deficit;
+static void __ieee80211_insert_txq(struct rb_root_cached *root,
+ struct txq_info *txqi)
+{
+ struct rb_node **new = &root->rb_root.rb_node;
+ struct airtime_info *old_air, *new_air;
+ struct rb_node *parent = NULL;
+ struct txq_info *__txqi;
+ bool leftmost = true;
+
+ while (*new) {
+ parent = *new;
+ __txqi = rb_entry(parent, struct txq_info, schedule_order);
+ old_air = to_airtime_info(&__txqi->txq);
+ new_air = to_airtime_info(&txqi->txq);
+
+ if (new_air->v_t <= old_air->v_t) {
+ new = &parent->rb_left;
+ } else {
+ new = &parent->rb_right;
+ leftmost = false;
+ }
+ }
- if (aql_check)
- found_eligible_txq = true;
+ rb_link_node(&txqi->schedule_order, parent, new);
+ rb_insert_color_cached(&txqi->schedule_order, root, leftmost);
+}
- if (deficit < 0)
- sta->airtime[txqi->txq.ac].deficit +=
- sta->airtime_weight;
+void ieee80211_resort_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq)
+{
+ struct airtime_info *air_info = to_airtime_info(txq);
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct txq_info *txqi = to_txq_info(txq);
+ struct airtime_sched_info *air_sched;
- if (deficit < 0 || !aql_check) {
- list_move_tail(&txqi->schedule_order,
- &local->active_txqs[txqi->txq.ac]);
- goto begin;
+ air_sched = &local->airtime[txq->ac];
+
+ lockdep_assert_held(&air_sched->lock);
+
+ if (!RB_EMPTY_NODE(&txqi->schedule_order)) {
+ struct airtime_info *a_prev = NULL, *a_next = NULL;
+ struct txq_info *t_prev, *t_next;
+ struct rb_node *n_prev, *n_next;
+
+ /* Erasing a node can cause an expensive rebalancing operation,
+ * so we check the previous and next nodes first and only remove
+ * and re-insert if the current node is not already in the
+ * correct position.
+ */
+ if ((n_prev = rb_prev(&txqi->schedule_order)) != NULL) {
+ t_prev = container_of(n_prev, struct txq_info, schedule_order);
+ a_prev = to_airtime_info(&t_prev->txq);
}
+
+ if ((n_next = rb_next(&txqi->schedule_order)) != NULL) {
+ t_next = container_of(n_next, struct txq_info, schedule_order);
+ a_next = to_airtime_info(&t_next->txq);
+ }
+
+ if ((!a_prev || a_prev->v_t <= air_info->v_t) &&
+ (!a_next || a_next->v_t > air_info->v_t))
+ return;
+
+ if (air_sched->schedule_pos == &txqi->schedule_order)
+ air_sched->schedule_pos = n_prev;
+
+ rb_erase_cached(&txqi->schedule_order,
+ &air_sched->active_txqs);
+ RB_CLEAR_NODE(&txqi->schedule_order);
+ __ieee80211_insert_txq(&air_sched->active_txqs, txqi);
}
+}
+void ieee80211_update_airtime_weight(struct ieee80211_local *local,
+ struct airtime_sched_info *air_sched,
+ u64 now, bool force)
+{
+ struct airtime_info *air_info, *tmp;
+ u64 weight_sum = 0;
+
+ if (unlikely(!now))
+ now = ktime_get_boottime_ns();
- if (txqi->schedule_round == local->schedule_round[ac])
+ lockdep_assert_held(&air_sched->lock);
+
+ if (!force && air_sched->last_weight_update < now - AIRTIME_ACTIVE_DURATION)
+ return;
+
+ list_for_each_entry_safe(air_info, tmp, &air_sched->active_list, list) {
+ if (airtime_is_active(air_info, now))
+ weight_sum += air_info->weight;
+ else
+ list_del_init(&air_info->list);
+ }
+ airtime_weight_sum_set(air_sched, weight_sum);
+ air_sched->last_weight_update = now;
+}
+
+void ieee80211_schedule_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq)
+ __acquires(txq_lock) __releases(txq_lock)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct txq_info *txqi = to_txq_info(txq);
+ struct airtime_sched_info *air_sched;
+ u64 now = ktime_get_boottime_ns();
+ struct airtime_info *air_info;
+ u8 ac = txq->ac;
+ bool was_active;
+
+ air_sched = &local->airtime[ac];
+ air_info = to_airtime_info(txq);
+
+ spin_lock_bh(&air_sched->lock);
+ was_active = airtime_is_active(air_info, now);
+ airtime_set_active(air_sched, air_info, now);
+
+ if (!RB_EMPTY_NODE(&txqi->schedule_order))
goto out;
- list_del_init(&txqi->schedule_order);
- txqi->schedule_round = local->schedule_round[ac];
- ret = &txqi->txq;
+ /* If the station has been inactive for a while, catch up its v_t so it
+ * doesn't get indefinite priority; see comment above the definition of
+ * AIRTIME_MAX_BEHIND.
+ */
+ if ((!was_active && air_info->v_t < air_sched->v_t) ||
+ air_info->v_t < air_sched->v_t - AIRTIME_MAX_BEHIND)
+ air_info->v_t = air_sched->v_t;
+
+ ieee80211_update_airtime_weight(local, air_sched, now, !was_active);
+ __ieee80211_insert_txq(&air_sched->active_txqs, txqi);
out:
- spin_unlock_bh(&local->active_txq_lock[ac]);
- return ret;
+ spin_unlock_bh(&air_sched->lock);
}
-EXPORT_SYMBOL(ieee80211_next_txq);
+EXPORT_SYMBOL(ieee80211_schedule_txq);
-void __ieee80211_schedule_txq(struct ieee80211_hw *hw,
- struct ieee80211_txq *txq,
- bool force)
+static void __ieee80211_unschedule_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq,
+ bool purge)
{
struct ieee80211_local *local = hw_to_local(hw);
struct txq_info *txqi = to_txq_info(txq);
+ struct airtime_sched_info *air_sched;
+ struct airtime_info *air_info;
- spin_lock_bh(&local->active_txq_lock[txq->ac]);
-
- if (list_empty(&txqi->schedule_order) &&
- (force || !skb_queue_empty(&txqi->frags) ||
- txqi->tin.backlog_packets)) {
- /* If airtime accounting is active, always enqueue STAs at the
- * head of the list to ensure that they only get moved to the
- * back by the airtime DRR scheduler once they have a negative
- * deficit. A station that already has a negative deficit will
- * get immediately moved to the back of the list on the next
- * call to ieee80211_next_txq().
- */
- if (txqi->txq.sta && local->airtime_flags &&
- wiphy_ext_feature_isset(local->hw.wiphy,
- NL80211_EXT_FEATURE_AIRTIME_FAIRNESS))
- list_add(&txqi->schedule_order,
- &local->active_txqs[txq->ac]);
- else
- list_add_tail(&txqi->schedule_order,
- &local->active_txqs[txq->ac]);
+ air_sched = &local->airtime[txq->ac];
+ air_info = to_airtime_info(&txqi->txq);
+
+ lockdep_assert_held(&air_sched->lock);
+
+ if (purge) {
+ list_del_init(&air_info->list);
+ ieee80211_update_airtime_weight(local, air_sched, 0, true);
}
- spin_unlock_bh(&local->active_txq_lock[txq->ac]);
+ if (RB_EMPTY_NODE(&txqi->schedule_order))
+ return;
+
+ if (air_sched->schedule_pos == &txqi->schedule_order)
+ air_sched->schedule_pos = rb_prev(&txqi->schedule_order);
+
+ if (!purge)
+ airtime_set_active(air_sched, air_info, ktime_get_boottime_ns());
+
+ rb_erase_cached(&txqi->schedule_order,
+ &air_sched->active_txqs);
+ RB_CLEAR_NODE(&txqi->schedule_order);
+}
+
+void ieee80211_unschedule_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq,
+ bool purge)
+ __acquires(txq_lock) __releases(txq_lock)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ spin_lock_bh(&local->airtime[txq->ac].lock);
+ __ieee80211_unschedule_txq(hw, txq, purge);
+ spin_unlock_bh(&local->airtime[txq->ac].lock);
+}
+
+void ieee80211_return_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq, bool force)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct txq_info *txqi = to_txq_info(txq);
+
+ spin_lock_bh(&local->airtime[txq->ac].lock);
+
+ if (!RB_EMPTY_NODE(&txqi->schedule_order) && !force &&
+ !txq_has_queue(txq))
+ __ieee80211_unschedule_txq(hw, txq, false);
+
+ spin_unlock_bh(&local->airtime[txq->ac].lock);
}
-EXPORT_SYMBOL(__ieee80211_schedule_txq);
+EXPORT_SYMBOL(ieee80211_return_txq);
DEFINE_STATIC_KEY_FALSE(aql_disable);
bool ieee80211_txq_airtime_check(struct ieee80211_hw *hw,
struct ieee80211_txq *txq)
{
- struct sta_info *sta;
+ struct airtime_info *air_info = to_airtime_info(txq);
struct ieee80211_local *local = hw_to_local(hw);
if (!wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL))
@@ -3854,15 +4005,12 @@ bool ieee80211_txq_airtime_check(struct ieee80211_hw *hw,
if (unlikely(txq->tid == IEEE80211_NUM_TIDS))
return true;
- sta = container_of(txq->sta, struct sta_info, sta);
- if (atomic_read(&sta->airtime[txq->ac].aql_tx_pending) <
- sta->airtime[txq->ac].aql_limit_low)
+ if (atomic_read(&air_info->aql_tx_pending) < air_info->aql_limit_low)
return true;
if (atomic_read(&local->aql_total_pending_airtime) <
local->aql_threshold &&
- atomic_read(&sta->airtime[txq->ac].aql_tx_pending) <
- sta->airtime[txq->ac].aql_limit_high)
+ atomic_read(&air_info->aql_tx_pending) < air_info->aql_limit_high)
return true;
return false;
@@ -3872,60 +4020,59 @@ EXPORT_SYMBOL(ieee80211_txq_airtime_check);
bool ieee80211_txq_may_transmit(struct ieee80211_hw *hw,
struct ieee80211_txq *txq)
{
+ struct txq_info *first_txqi = NULL, *txqi = to_txq_info(txq);
struct ieee80211_local *local = hw_to_local(hw);
- struct txq_info *iter, *tmp, *txqi = to_txq_info(txq);
- struct sta_info *sta;
- u8 ac = txq->ac;
+ struct airtime_sched_info *air_sched;
+ struct airtime_info *air_info;
+ struct rb_node *node = NULL;
+ bool ret = false;
+ u64 now;
- spin_lock_bh(&local->active_txq_lock[ac]);
- if (!txqi->txq.sta)
- goto out;
+ if (!ieee80211_txq_airtime_check(hw, txq))
+ return false;
+
+ air_sched = &local->airtime[txq->ac];
+ spin_lock_bh(&air_sched->lock);
- if (list_empty(&txqi->schedule_order))
+ if (RB_EMPTY_NODE(&txqi->schedule_order))
goto out;
- list_for_each_entry_safe(iter, tmp, &local->active_txqs[ac],
- schedule_order) {
- if (iter == txqi)
- break;
+ now = ktime_get_boottime_ns();
- if (!iter->txq.sta) {
- list_move_tail(&iter->schedule_order,
- &local->active_txqs[ac]);
- continue;
- }
- sta = container_of(iter->txq.sta, struct sta_info, sta);
- if (sta->airtime[ac].deficit < 0)
- sta->airtime[ac].deficit += sta->airtime_weight;
- list_move_tail(&iter->schedule_order, &local->active_txqs[ac]);
- }
+ /* Like in ieee80211_next_txq(), make sure the first station in the
+ * scheduling order is eligible for transmission to avoid starvation.
+ */
+ node = rb_first_cached(&air_sched->active_txqs);
+ if (node) {
+ first_txqi = container_of(node, struct txq_info,
+ schedule_order);
+ air_info = to_airtime_info(&first_txqi->txq);
- sta = container_of(txqi->txq.sta, struct sta_info, sta);
- if (sta->airtime[ac].deficit >= 0)
- goto out;
+ if (air_sched->v_t < air_info->v_t)
+ airtime_catchup_v_t(air_sched, air_info->v_t, now);
+ }
- sta->airtime[ac].deficit += sta->airtime_weight;
- list_move_tail(&txqi->schedule_order, &local->active_txqs[ac]);
- spin_unlock_bh(&local->active_txq_lock[ac]);
+ air_info = to_airtime_info(&txqi->txq);
+ if (air_info->v_t <= air_sched->v_t) {
+ air_sched->last_schedule_activity = now;
+ ret = true;
+ }
- return false;
+ spin_unlock_bh(&air_sched->lock);
out:
- if (!list_empty(&txqi->schedule_order))
- list_del_init(&txqi->schedule_order);
- spin_unlock_bh(&local->active_txq_lock[ac]);
-
- return true;
+ return ret;
}
EXPORT_SYMBOL(ieee80211_txq_may_transmit);
void ieee80211_txq_schedule_start(struct ieee80211_hw *hw, u8 ac)
{
struct ieee80211_local *local = hw_to_local(hw);
+ struct airtime_sched_info *air_sched = &local->airtime[ac];
- spin_lock_bh(&local->active_txq_lock[ac]);
- local->schedule_round[ac]++;
- spin_unlock_bh(&local->active_txq_lock[ac]);
+ spin_lock_bh(&air_sched->lock);
+ air_sched->schedule_pos = NULL;
+ spin_unlock_bh(&air_sched->lock);
}
EXPORT_SYMBOL(ieee80211_txq_schedule_start);