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330-mac80211-switch-airtime-fairness-back-to-deficit-rou.patch
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330-mac80211-switch-airtime-fairness-back-to-deficit-rou.patch
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From: Felix Fietkau <nbd@nbd.name>
Date: Sun, 19 Jun 2022 23:13:05 +0200
Subject: [PATCH] mac80211: switch airtime fairness back to deficit round-robin
scheduling
This reverts commits 6a789ba679d652587532cec2a0e0274fda172f3b and
2433647bc8d983a543e7d31b41ca2de1c7e2c198.
The virtual time scheduler code has a number of issues:
- queues slowed down by hardware/firmware powersave handling were not properly
handled.
- on ath10k in push-pull mode, tx queues that the driver tries to pull from
were starved, causing excessive latency
- delay between tx enqueue and reported airtime use were causing excessively
bursty tx behavior
The bursty behavior may also be present on the round-robin scheduler, but there
it is much easier to fix without introducing additional regressions
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -6666,6 +6666,9 @@ static inline void ieee80211_txq_schedul
{
}
+void __ieee80211_schedule_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq, bool force);
+
/**
* ieee80211_schedule_txq - schedule a TXQ for transmission
*
@@ -6678,7 +6681,11 @@ static inline void ieee80211_txq_schedul
* The driver may call this function if it has buffered packets for
* this TXQ internally.
*/
-void ieee80211_schedule_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq);
+static inline void
+ieee80211_schedule_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq)
+{
+ __ieee80211_schedule_txq(hw, txq, true);
+}
/**
* ieee80211_return_txq - return a TXQ previously acquired by ieee80211_next_txq()
@@ -6690,8 +6697,12 @@ void ieee80211_schedule_txq(struct ieee8
* The driver may set force=true if it has buffered packets for this TXQ
* internally.
*/
-void ieee80211_return_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq,
- bool force);
+static inline void
+ieee80211_return_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq,
+ bool force)
+{
+ __ieee80211_schedule_txq(hw, txq, force);
+}
/**
* ieee80211_txq_may_transmit - check whether TXQ is allowed to transmit
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1554,38 +1554,6 @@ static void sta_apply_mesh_params(struct
#endif
}
-static void sta_apply_airtime_params(struct ieee80211_local *local,
- struct sta_info *sta,
- struct station_parameters *params)
-{
- u8 ac;
-
- 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];
- struct txq_info *txqi;
- u8 tid;
-
- 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);
- }
-}
-
static int sta_apply_parameters(struct ieee80211_local *local,
struct sta_info *sta,
struct station_parameters *params)
@@ -1773,8 +1741,7 @@ static int sta_apply_parameters(struct i
sta_apply_mesh_params(local, sta, params);
if (params->airtime_weight)
- sta_apply_airtime_params(local, sta, params);
-
+ sta->airtime_weight = params->airtime_weight;
/* set the STA state after all sta info from usermode has been set */
if (test_sta_flag(sta, WLAN_STA_TDLS_PEER) ||
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -216,14 +216,14 @@ static ssize_t aql_txq_limit_read(struct
"VI %u %u\n"
"BE %u %u\n"
"BK %u %u\n",
- 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);
+ 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]);
return simple_read_from_buffer(user_buf, count, ppos,
buf, len);
}
@@ -255,11 +255,11 @@ static ssize_t aql_txq_limit_write(struc
if (ac >= IEEE80211_NUM_ACS)
return -EINVAL;
- q_limit_low_old = local->airtime[ac].aql_txq_limit_low;
- q_limit_high_old = local->airtime[ac].aql_txq_limit_high;
+ q_limit_low_old = local->aql_txq_limit_low[ac];
+ q_limit_high_old = local->aql_txq_limit_high[ac];
- local->airtime[ac].aql_txq_limit_low = q_limit_low;
- local->airtime[ac].aql_txq_limit_high = q_limit_high;
+ local->aql_txq_limit_low[ac] = q_limit_low;
+ local->aql_txq_limit_high[ac] = q_limit_high;
mutex_lock(&local->sta_mtx);
list_for_each_entry(sta, &local->sta_list, list) {
@@ -382,46 +382,6 @@ static const struct file_operations forc
.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)
@@ -672,11 +632,7 @@ void debugfs_hw_add(struct ieee80211_loc
if (local->ops->wake_tx_queue)
DEBUGFS_ADD_MODE(aqm, 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_MODE(airtime_flags, 0600);
DEBUGFS_ADD(aql_txq_limit);
debugfs_create_u32("aql_threshold", 0600,
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -512,34 +512,6 @@ 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 */
@@ -685,10 +657,8 @@ static void add_common_files(struct ieee
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)
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -202,7 +202,7 @@ static ssize_t sta_airtime_read(struct f
size_t bufsz = 400;
char *buf = kzalloc(bufsz, GFP_KERNEL), *p = buf;
u64 rx_airtime = 0, tx_airtime = 0;
- u64 v_t[IEEE80211_NUM_ACS];
+ s64 deficit[IEEE80211_NUM_ACS];
ssize_t rv;
int ac;
@@ -210,18 +210,18 @@ static ssize_t sta_airtime_read(struct f
return -ENOMEM;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
- spin_lock_bh(&local->airtime[ac].lock);
+ spin_lock_bh(&local->active_txq_lock[ac]);
rx_airtime += sta->airtime[ac].rx_airtime;
tx_airtime += sta->airtime[ac].tx_airtime;
- v_t[ac] = sta->airtime[ac].v_t;
- spin_unlock_bh(&local->airtime[ac].lock);
+ deficit[ac] = sta->airtime[ac].deficit;
+ spin_unlock_bh(&local->active_txq_lock[ac]);
}
p += scnprintf(p, bufsz + buf - p,
"RX: %llu us\nTX: %llu us\nWeight: %u\n"
- "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]);
+ "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]);
rv = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
kfree(buf);
@@ -236,11 +236,11 @@ static ssize_t sta_airtime_write(struct
int ac;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
- spin_lock_bh(&local->airtime[ac].lock);
+ spin_lock_bh(&local->active_txq_lock[ac]);
sta->airtime[ac].rx_airtime = 0;
sta->airtime[ac].tx_airtime = 0;
- sta->airtime[ac].v_t = 0;
- spin_unlock_bh(&local->airtime[ac].lock);
+ sta->airtime[ac].deficit = sta->airtime_weight;
+ spin_unlock_bh(&local->active_txq_lock[ac]);
}
return count;
@@ -263,10 +263,10 @@ static ssize_t sta_aql_read(struct file
return -ENOMEM;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
- spin_lock_bh(&local->airtime[ac].lock);
+ spin_lock_bh(&local->active_txq_lock[ac]);
q_limit_l[ac] = sta->airtime[ac].aql_limit_low;
q_limit_h[ac] = sta->airtime[ac].aql_limit_high;
- spin_unlock_bh(&local->airtime[ac].lock);
+ spin_unlock_bh(&local->active_txq_lock[ac]);
q_depth[ac] = atomic_read(&sta->airtime[ac].aql_tx_pending);
}
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -863,16 +863,20 @@ enum txq_info_flags {
* @def_flow: used as a fallback flow when a packet destined to @tin hashes to
* a fq_flow which is already owned by a different tin
* @def_cvars: codel vars for @def_flow
- * @schedule_order: used with ieee80211_local->active_txqs
* @frags: used to keep fragments created after dequeue
+ * @schedule_order: used with ieee80211_local->active_txqs
+ * @schedule_round: counter to prevent infinite loops on TXQ scheduling
*/
struct txq_info {
struct fq_tin tin;
struct codel_vars def_cvars;
struct codel_stats cstats;
- struct rb_node schedule_order;
+
+ u16 schedule_round;
+ struct list_head schedule_order;
struct sk_buff_head frags;
+
unsigned long flags;
/* keep last! */
@@ -949,8 +953,6 @@ 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;
@@ -1185,44 +1187,6 @@ 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 {
@@ -1236,8 +1200,13 @@ struct ieee80211_local {
struct codel_params cparams;
/* protects active_txqs and txqi->schedule_order */
- struct airtime_sched_info airtime[IEEE80211_NUM_ACS];
+ spinlock_t active_txq_lock[IEEE80211_NUM_ACS];
+ struct list_head active_txqs[IEEE80211_NUM_ACS];
+ u16 schedule_round[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;
@@ -1654,125 +1623,6 @@ static inline bool txq_has_queue(struct
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) ||
@@ -2018,14 +1868,6 @@ int ieee80211_tx_control_port(struct wip
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,
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -2192,9 +2192,6 @@ int ieee80211_if_add(struct ieee80211_lo
}
}
- 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;
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -707,13 +707,10 @@ struct ieee80211_hw *ieee80211_alloc_hw_
spin_lock_init(&local->queue_stop_reason_lock);
for (i = 0; i < IEEE80211_NUM_ACS; 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 =
+ 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] =
IEEE80211_DEFAULT_AQL_TXQ_LIMIT_H;
}
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1583,8 +1583,12 @@ static void sta_ps_start(struct sta_info
for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
struct ieee80211_txq *txq = sta->sta.txq[tid];
+ struct txq_info *txqi = to_txq_info(txq);
- ieee80211_unschedule_txq(&local->hw, txq, false);
+ 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]);
if (txq_has_queue(txq))
set_bit(tid, &sta->txq_buffered_tids);
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -426,11 +426,15 @@ struct sta_info *sta_info_alloc(struct i
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]);
- init_airtime_info(&sta->airtime[i], &local->airtime[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];
}
for (i = 0; i < IEEE80211_NUM_TIDS; i++)
@@ -1889,59 +1893,24 @@ void ieee80211_sta_set_buffered(struct i
}
EXPORT_SYMBOL(ieee80211_sta_set_buffered);
-void ieee80211_register_airtime(struct ieee80211_txq *txq,
- u32 tx_airtime, u32 rx_airtime)
+void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
+ u32 tx_airtime, u32 rx_airtime)
{
- 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;
+ 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);
u32 airtime = 0;
- air_sched = &local->airtime[txq->ac];
- air_info = to_airtime_info(txq);
-
- if (local->airtime_flags & AIRTIME_USE_TX)
+ if (sta->local->airtime_flags & AIRTIME_USE_TX)
airtime += tx_airtime;
- if (local->airtime_flags & AIRTIME_USE_RX)
+ if (sta->local->airtime_flags & AIRTIME_USE_RX)
airtime += rx_airtime;
- /* 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);
+ 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]);
}
EXPORT_SYMBOL(ieee80211_sta_register_airtime);
@@ -2385,7 +2354,7 @@ void sta_set_sinfo(struct sta_info *sta,
}
if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT))) {
- sinfo->airtime_weight = sta->airtime[0].weight;
+ sinfo->airtime_weight = sta->airtime_weight;
sinfo->filled |= BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT);
}
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -135,25 +135,18 @@ 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;
- u64 v_t;
- u64 last_scheduled;
- struct list_head list;
+ s64 deficit;
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;
@@ -523,6 +516,7 @@ struct ieee80211_fragment_cache {
* @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
@@ -653,6 +647,7 @@ 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.
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -983,25 +983,6 @@ static void __ieee80211_tx_status(struct
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
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -18,7 +18,6 @@
#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>
@@ -1480,7 +1479,7 @@ void ieee80211_txq_init(struct ieee80211
codel_vars_init(&txqi->def_cvars);
codel_stats_init(&txqi->cstats);
__skb_queue_head_init(&txqi->frags);
- RB_CLEAR_NODE(&txqi->schedule_order);
+ INIT_LIST_HEAD(&txqi->schedule_order);
txqi->txq.vif = &sdata->vif;
@@ -1524,7 +1523,9 @@ void ieee80211_txq_purge(struct ieee8021
ieee80211_purge_tx_queue(&local->hw, &txqi->frags);
spin_unlock_bh(&fq->lock);
- ieee80211_unschedule_txq(&local->hw, &txqi->txq, true);
+ 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]);
}
void ieee80211_txq_set_params(struct ieee80211_local *local)
@@ -3819,259 +3820,102 @@ 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_coarse_boottime_ns();
struct ieee80211_txq *ret = NULL;
- struct airtime_info *air_info;
- struct txq_info *txqi = NULL;
- struct rb_node *node;
- bool first = false;
+ struct txq_info *txqi = NULL, *head = NULL;
+ bool found_eligible_txq = false;
- air_sched = &local->airtime[ac];
- spin_lock_bh(&air_sched->lock);
+ spin_lock_bh(&local->active_txq_lock[ac]);
- 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;
-
- 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)))
+ begin:
+ txqi = list_first_entry_or_null(&local->active_txqs[ac],
+ struct txq_info,
+ schedule_order);
+ if (!txqi)
goto out;
- if (!ieee80211_txq_airtime_check(hw, &txqi->txq)) {
- first = false;
- goto begin;
- }
-
- 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);
-
-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 (txqi == head) {
+ if (!found_eligible_txq)
+ goto out;
+ else
+ found_eligible_txq = false;
}
- rb_link_node(&txqi->schedule_order, parent, new);
- rb_insert_color_cached(&txqi->schedule_order, root, leftmost);
-}
-
-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;
-
- air_sched = &local->airtime[txq->ac];
+ if (!head)
+ head = txqi;
- 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;
+ 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;
- /* 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 (aql_check)
+ found_eligible_txq = true;
- 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 (deficit < 0)
+ sta->airtime[txqi->txq.ac].deficit +=
+ sta->airtime_weight;
+
+ if (deficit < 0 || !aql_check) {
+ list_move_tail(&txqi->schedule_order,
+ &local->active_txqs[txqi->txq.ac]);
+ goto begin;
}
-
- 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_coarse_boottime_ns();
-
- 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);