intermediate precision (which was lost in a later stage anyway).
The new shift value limits the maximum weight to 4096, which should be more
-than enough. Any values bigger than that will be rejected.
+than enough. Any values bigger than that will be clamped to the upper limit.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
---- a/net/mac80211/cfg.c
-+++ b/net/mac80211/cfg.c
-@@ -1602,6 +1602,9 @@ static int sta_apply_parameters(struct i
- mask = params->sta_flags_mask;
- set = params->sta_flags_set;
-
-+ if (params->airtime_weight > BIT(IEEE80211_RECIPROCAL_SHIFT_STA))
-+ return -EINVAL;
-+
- if (ieee80211_vif_is_mesh(&sdata->vif)) {
- /*
- * In mesh mode, ASSOCIATED isn't part of the nl80211
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
-@@ -1666,50 +1666,33 @@ static inline struct airtime_info *to_ai
+@@ -1666,50 +1666,34 @@ static inline struct airtime_info *to_ai
/* 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.
-static inline void airtime_weight_set(struct airtime_info *air_info, u16 weight)
+static inline void airtime_weight_set(struct airtime_info *air_info, u32 weight)
{
++ weight = min_t(u32, weight, BIT(IEEE80211_RECIPROCAL_SHIFT_STA));
if (air_info->weight == weight)
return;
+++ /dev/null
-From: Felix Fietkau <nbd@nbd.name>
-Date: Sat, 11 Jun 2022 16:34:32 +0200
-Subject: [PATCH] mac80211: improve AQL tx time estimation
-
-If airtime cannot be calculated because of missing or unsupported rate info,
-use the smallest possible non-zero value for estimated tx time.
-This improves handling of these cases by preventing queueing of as many packets
-as the driver/hardware queue can hold for these stations.
-Also slightly improve limiting queueing by explicitly rounding up small values.
-
-Signed-off-by: Felix Fietkau <nbd@nbd.name>
----
-
---- a/include/net/mac80211.h
-+++ b/include/net/mac80211.h
-@@ -1107,20 +1107,24 @@ struct ieee80211_tx_info {
- };
- };
-
-+#define IEEE80211_TX_TIME_EST_UNIT 4
-+
-+static inline u16
-+ieee80211_info_get_tx_time_est(struct ieee80211_tx_info *info)
-+{
-+ return info->tx_time_est * IEEE80211_TX_TIME_EST_UNIT;
-+}
-+
- static inline u16
- ieee80211_info_set_tx_time_est(struct ieee80211_tx_info *info, u16 tx_time_est)
- {
- /* We only have 10 bits in tx_time_est, so store airtime
- * in increments of 4us and clamp the maximum to 2**12-1
- */
-- info->tx_time_est = min_t(u16, tx_time_est, 4095) >> 2;
-- return info->tx_time_est << 2;
--}
-+ tx_time_est = DIV_ROUND_UP(tx_time_est, IEEE80211_TX_TIME_EST_UNIT);
-+ info->tx_time_est = min_t(u16, tx_time_est, BIT(10) - 1);
-
--static inline u16
--ieee80211_info_get_tx_time_est(struct ieee80211_tx_info *info)
--{
-- return info->tx_time_est << 2;
-+ return ieee80211_info_get_tx_time_est(info);
- }
-
- /**
---- a/net/mac80211/status.c
-+++ b/net/mac80211/status.c
-@@ -999,6 +999,8 @@ static void __ieee80211_tx_status(struct
- NULL,
- skb->len,
- false);
-+ if (!airtime)
-+ airtime = IEEE80211_TX_TIME_EST_UNIT;
-
- ieee80211_register_airtime(txq, airtime, 0);
- }
---- a/net/mac80211/tx.c
-+++ b/net/mac80211/tx.c
-@@ -3798,13 +3798,12 @@ encap_out:
-
- airtime = ieee80211_calc_expected_tx_airtime(hw, vif, txq->sta,
- skb->len, ampdu);
-- if (airtime) {
-- airtime = ieee80211_info_set_tx_time_est(info, airtime);
-- ieee80211_sta_update_pending_airtime(local, tx.sta,
-- txq->ac,
-- airtime,
-- false);
-- }
-+ if (!airtime)
-+ airtime = IEEE80211_TX_TIME_EST_UNIT;
-+
-+ airtime = ieee80211_info_set_tx_time_est(info, airtime);
-+ ieee80211_sta_update_pending_airtime(local, tx.sta, txq->ac,
-+ airtime, false);
- }
-
- return skb;
/* 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.
-@@ -1749,6 +1763,7 @@ static inline void init_airtime_info(str
+@@ -1750,6 +1764,7 @@ static inline void init_airtime_info(str
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);
WARN_ON_ONCE(softirq_count() == 0);
-@@ -3791,20 +3801,35 @@ begin:
+@@ -3791,21 +3801,26 @@ begin:
encap_out:
IEEE80211_SKB_CB(skb)->control.vif = vif;
-
- airtime = ieee80211_calc_expected_tx_airtime(hw, vif, txq->sta,
- skb->len, ampdu);
-- if (!airtime)
-- airtime = IEEE80211_TX_TIME_EST_UNIT;
--
-- airtime = ieee80211_info_set_tx_time_est(info, airtime);
-- ieee80211_sta_update_pending_airtime(local, tx.sta, txq->ac,
-- airtime, false);
+- if (airtime) {
+- airtime = ieee80211_info_set_tx_time_est(info, airtime);
+- ieee80211_sta_update_pending_airtime(local, tx.sta,
+- txq->ac,
+- airtime,
+- false);
+- }
- }
+ if (!vif)
+ return skb;
+ airtime = ieee80211_calc_expected_tx_airtime(hw, vif, txq->sta,
+ skb->len, ampdu);
+ if (!airtime)
-+ airtime = IEEE80211_TX_TIME_EST_UNIT;
++ return skb;
+
-+ /*
-+ * Tx queue scheduling always happens in airtime order and queues are
-+ * sorted by virtual time + pending AQL budget.
-+ * If AQL is not supported, pending AQL budget is always zero.
-+ * If airtime fairness is not supported, virtual time won't be directly
-+ * increased by driver tx completion.
-+ * Because of that, we register estimated tx time as airtime if either
-+ * AQL or ATF support is missing.
-+ */
+ if (!wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL) ||
+ !wiphy_ext_feature_isset(local->hw.wiphy,
+ NL80211_EXT_FEATURE_AIRTIME_FAIRNESS))
return skb;
-@@ -3815,85 +3840,92 @@ out:
+@@ -3816,85 +3831,95 @@ out:
}
EXPORT_SYMBOL(ieee80211_tx_dequeue);
-+static struct ieee80211_txq *
++static void
+airtime_info_next_txq_idx(struct airtime_info *air_info)
+{
+ air_info->txq_idx++;
+ if (air_info->txq_idx >= ARRAY_SIZE(air_info->txq) ||
+ !air_info->txq[air_info->txq_idx])
+ air_info->txq_idx = 0;
-+ return air_info->txq[air_info->txq_idx];
+}
+
struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw, u8 ac)
-
- if (!ieee80211_txq_airtime_check(hw, &txqi->txq)) {
- first = false;
-+ txq = airtime_info_next_txq_idx(air_info);
++ airtime_info_next_txq_idx(air_info);
+ txq_idx = air_info->txq_idx;
-+ if (!ieee80211_txq_airtime_check(hw, txq))
++ txq = air_info->txq[txq_idx];
++ if (!txq || !ieee80211_txq_airtime_check(hw, txq))
goto begin;
+
+ while (1) {
+ if (txq_has_queue(txq))
+ break;
+
-+ txq = airtime_info_next_txq_idx(air_info);
++ airtime_info_next_txq_idx(air_info);
++ txq = air_info->txq[air_info->txq_idx];
+ if (txq_idx == air_info->txq_idx)
+ goto begin;
++ }
++
++ if (air_info->v_t_cur > air_sched->v_t) {
++ if (node == airtime_sched_peek(&air_sched->active_txqs))
++ airtime_catchup_v_t(air_sched, air_info->v_t_cur, now);
}
-+ if (air_info->v_t_cur > air_sched->v_t)
-+ airtime_catchup_v_t(air_sched, air_info->v_t_cur, now);
-+
air_sched->schedule_pos = node;
air_sched->last_schedule_activity = now;
- ret = &txqi->txq;
struct ieee80211_local *local = hw_to_local(hw);
struct txq_info *txqi = to_txq_info(txq);
struct airtime_sched_info *air_sched;
-@@ -3901,41 +3933,7 @@ void ieee80211_resort_txq(struct ieee802
+@@ -3902,41 +3927,7 @@ void ieee80211_resort_txq(struct ieee802
air_sched = &local->airtime[txq->ac];
lockdep_assert_held(&air_sched->lock);
}
void ieee80211_update_airtime_weight(struct ieee80211_local *local,
-@@ -3984,7 +3982,7 @@ void ieee80211_schedule_txq(struct ieee8
+@@ -3985,7 +3976,7 @@ void ieee80211_schedule_txq(struct ieee8
was_active = airtime_is_active(air_info, now);
airtime_set_active(air_sched, air_info, now);
goto out;
/* If the station has been inactive for a while, catch up its v_t so it
-@@ -3996,7 +3994,7 @@ void ieee80211_schedule_txq(struct ieee8
+@@ -3997,7 +3988,7 @@ void ieee80211_schedule_txq(struct ieee8
air_info->v_t = air_sched->v_t;
ieee80211_update_airtime_weight(local, air_sched, now, !was_active);
out:
spin_unlock_bh(&air_sched->lock);
-@@ -4017,24 +4015,14 @@ static void __ieee80211_unschedule_txq(s
-
- lockdep_assert_held(&air_sched->lock);
-
-+ airtime_sched_delete(&air_sched->active_txqs, &air_info->schedule_order);
- if (purge) {
- list_del_init(&air_info->list);
+@@ -4023,19 +4014,10 @@ static void __ieee80211_unschedule_txq(s
ieee80211_update_airtime_weight(local, air_sched, 0, true);
-- }
--
+ }
+
- 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)
-+ } else {
++ airtime_sched_delete(&air_sched->active_txqs, &air_info->schedule_order);
+ if (!purge)
airtime_set_active(air_sched, air_info,
ktime_get_coarse_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,
-@@ -4054,14 +4042,22 @@ void ieee80211_return_txq(struct ieee802
+@@ -4055,14 +4037,24 @@ void ieee80211_return_txq(struct ieee802
{
struct ieee80211_local *local = hw_to_local(hw);
struct txq_info *txqi = to_txq_info(txq);
- spin_unlock_bh(&local->airtime[txq->ac].lock);
+ spin_lock_bh(&air_sched->lock);
-+ if (force || (txq_has_queue(txq) &&
-+ ieee80211_txq_airtime_check(hw, &txqi->txq)))
++ if (!ieee80211_txq_airtime_check(hw, &txqi->txq))
++ airtime_sched_delete(&air_sched->active_txqs,
++ &air_info->schedule_order);
++ else if (txq_has_queue(txq) || force)
+ __ieee80211_insert_txq(local, air_sched, txqi);
+ else
+ __ieee80211_unschedule_txq(hw, txq, false);
}
EXPORT_SYMBOL(ieee80211_return_txq);
-@@ -4113,9 +4109,6 @@ bool ieee80211_txq_may_transmit(struct i
+@@ -4101,46 +4093,48 @@ EXPORT_SYMBOL(ieee80211_txq_airtime_chec
+ 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 txq_info *txqi = to_txq_info(txq);
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct airtime_sched_info *air_sched;
++ struct airtime_sched_node *node = NULL;
+ struct airtime_info *air_info;
+- struct rb_node *node = NULL;
+ bool ret = false;
++ u32 aql_slack;
+ u64 now;
+
+-
+ if (!ieee80211_txq_airtime_check(hw, txq))
+ return false;
+
air_sched = &local->airtime[txq->ac];
spin_lock_bh(&air_sched->lock);
-
now = ktime_get_coarse_boottime_ns();
+ /* 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);
++ node = airtime_sched_peek(&air_sched->active_txqs);
+ if (node) {
+- first_txqi = container_of(node, struct txq_info,
+- schedule_order);
+- air_info = to_airtime_info(&first_txqi->txq);
++ air_info = container_of(node, struct airtime_info,
++ schedule_order);
+
+ if (air_sched->v_t < air_info->v_t)
+ airtime_catchup_v_t(air_sched, air_info->v_t, now);
+ }
+
air_info = to_airtime_info(&txqi->txq);
-@@ -4124,7 +4117,6 @@ bool ieee80211_txq_may_transmit(struct i
+- if (air_info->v_t <= air_sched->v_t) {
++ aql_slack = air_info->aql_limit_low;
++ aql_slack *= air_info->weight_reciprocal;
++ aql_slack >>= IEEE80211_RECIPROCAL_SHIFT_STA - IEEE80211_WEIGHT_SHIFT;
++ /*
++ * add extra slack of aql_limit_low in order to avoid queue
++ * starvation when bypassing normal scheduling order
++ */
++ if (air_info->v_t <= air_sched->v_t + aql_slack) {
+ air_sched->last_schedule_activity = now;
ret = true;
}
spin_unlock_bh(&air_sched->lock);
return ret;
}
-@@ -4135,9 +4127,7 @@ void ieee80211_txq_schedule_start(struct
+@@ -4151,9 +4145,7 @@ void ieee80211_txq_schedule_start(struct
struct ieee80211_local *local = hw_to_local(hw);
struct airtime_sched_info *air_sched = &local->airtime[ac];
+++ /dev/null
-From: Felix Fietkau <nbd@nbd.name>
-Date: Sat, 11 Jun 2022 17:28:02 +0200
-Subject: [PATCH] mac80211: fix ieee80211_txq_may_transmit regression
-
-After switching to the virtual time based airtime scheduler, there were reports
-that ath10k with tx queueing in push-pull mode was experiencing significant
-latency for some stations.
-The reason for it is the fact that queues from which the ath10k firmware wants
-to pull are getting starved by airtime fairness constraints.
-Theoretically the same issue should have been there before the switch to virtual
-time, however it seems that in the old round-robin implementation it was simply
-looping until the requested txq was considered eligible, which led to it pretty
-much ignoring fairness constraints anyway.
-
-In order to fix the immediate regression, let's make bypassing airtime fairness
-explicit for now.
-Also update the documentation for ieee80211_txq_may_transmit, which was still
-referring to implementation details of the old round-robin scheduler
-
-Fixes: 2433647bc8d9 ("mac80211: Switch to a virtual time-based airtime scheduler")
-Signed-off-by: Felix Fietkau <nbd@nbd.name>
----
-
---- a/include/net/mac80211.h
-+++ b/include/net/mac80211.h
-@@ -6700,22 +6700,11 @@ void ieee80211_return_txq(struct ieee802
- /**
- * ieee80211_txq_may_transmit - check whether TXQ is allowed to transmit
- *
-- * This function is used to check whether given txq is allowed to transmit by
-- * the airtime scheduler, and can be used by drivers to access the airtime
-- * fairness accounting without going using the scheduling order enfored by
-- * next_txq().
-+ * Returns %true if there is remaining AQL budget for the tx queue and %false
-+ * if it should be throttled. It will also mark the queue as active for the
-+ * airtime scheduler.
- *
-- * Returns %true if the airtime scheduler thinks the TXQ should be allowed to
-- * transmit, and %false if it should be throttled. This function can also have
-- * the side effect of rotating the TXQ in the scheduler rotation, which will
-- * eventually bring the deficit to positive and allow the station to transmit
-- * again.
-- *
-- * The API ieee80211_txq_may_transmit() also ensures that TXQ list will be
-- * aligned against driver's own round-robin scheduler list. i.e it rotates
-- * the TXQ list till it makes the requested node becomes the first entry
-- * in TXQ list. Thus both the TXQ list and driver's list are in sync. If this
-- * function returns %true, the driver is expected to schedule packets
-+ * If this function returns %true, the driver is expected to schedule packets
- * for transmission, and then return the TXQ through ieee80211_return_txq().
- *
- * @hw: pointer as obtained from ieee80211_alloc_hw()
---- a/net/mac80211/tx.c
-+++ b/net/mac80211/tx.c
-@@ -4100,15 +4100,13 @@ EXPORT_SYMBOL(ieee80211_txq_airtime_chec
- 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 *txqi = to_txq_info(txq);
- struct airtime_sched_info *air_sched;
- struct airtime_info *air_info;
-- struct rb_node *node = NULL;
- bool ret = false;
- u64 now;
-
--
- if (!ieee80211_txq_airtime_check(hw, txq))
- return false;
-
-@@ -4120,19 +4118,6 @@ bool ieee80211_txq_may_transmit(struct i
-
- now = ktime_get_coarse_boottime_ns();
-
-- /* 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);
--
-- if (air_sched->v_t < air_info->v_t)
-- airtime_catchup_v_t(air_sched, air_info->v_t, now);
-- }
--
- air_info = to_airtime_info(&txqi->txq);
- if (air_info->v_t <= air_sched->v_t) {
- air_sched->last_schedule_activity = now;
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
-@@ -2422,6 +2422,9 @@ struct ieee80211_txq {
+@@ -2418,6 +2418,9 @@ struct ieee80211_txq {
* usage and 802.11 frames with %RX_FLAG_ONLY_MONITOR set for monitor to
* the stack.
*
* @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
*/
enum ieee80211_hw_flags {
-@@ -2477,6 +2480,7 @@ enum ieee80211_hw_flags {
+@@ -2473,6 +2476,7 @@ enum ieee80211_hw_flags {
IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD,
IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD,
IEEE80211_HW_SUPPORTS_CONC_MON_RX_DECAP,
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
-@@ -1570,6 +1570,7 @@ enum ieee80211_smps_mode {
+@@ -1566,6 +1566,7 @@ enum ieee80211_smps_mode {
*
* @power_level: requested transmit power (in dBm), backward compatibility
* value only that is set to the minimum of all interfaces
*
* @chandef: the channel definition to tune to
* @radar_enabled: whether radar detection is enabled
-@@ -1590,6 +1591,7 @@ enum ieee80211_smps_mode {
+@@ -1586,6 +1587,7 @@ enum ieee80211_smps_mode {
struct ieee80211_conf {
u32 flags;
int power_level, dynamic_ps_timeout;
__NL80211_ATTR_AFTER_LAST,
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
-@@ -2843,6 +2843,19 @@ static int ieee80211_get_tx_power(struct
+@@ -2840,6 +2840,19 @@ static int ieee80211_get_tx_power(struct
return 0;
}
static void ieee80211_rfkill_poll(struct wiphy *wiphy)
{
struct ieee80211_local *local = wiphy_priv(wiphy);
-@@ -4547,6 +4560,7 @@ const struct cfg80211_ops mac80211_confi
+@@ -4544,6 +4557,7 @@ const struct cfg80211_ops mac80211_confi
.set_wiphy_params = ieee80211_set_wiphy_params,
.set_tx_power = ieee80211_set_tx_power,
.get_tx_power = ieee80211_get_tx_power,
projects / thirdparty / openwrt.git / commitdiff
