@@ -108,9 +108,15 @@
* The driver is expected to initialize its private per-queue data for stations
* and interfaces in the .add_interface and .sta_add ops.
*
- * The driver can't access the queue directly. To dequeue a frame, it calls
- * ieee80211_tx_dequeue(). Whenever mac80211 adds a new frame to a queue, it
- * calls the .wake_tx_queue driver op.
+ * The driver can't access the queue directly. To dequeue a frame from a
+ * txq, it calls ieee80211_tx_dequeue(). Whenever mac80211 adds a new frame to a
+ * queue, it calls the .wake_tx_queue driver op.
+ *
+ * Drivers can optionally delegate responsibility for scheduling queues to
+ * mac80211, to take advantage of airtime fairness accounting. In this case, to
+ * obtain the next queue to pull frames from, the driver calls
+ * ieee80211_next_txq(). The driver is then expected to return the txq using
+ * ieee80211_return_txq().
*
* For AP powersave TIM handling, the driver only needs to indicate if it has
* buffered packets in the driver specific data structures by calling
@@ -6088,7 +6094,8 @@ void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
* ieee80211_tx_dequeue - dequeue a packet from a software tx queue
*
* @hw: pointer as obtained from ieee80211_alloc_hw()
- * @txq: pointer obtained from station or virtual interface
+ * @txq: pointer obtained from station or virtual interface, or from
+ * ieee80211_next_txq()
*
* Returns the skb if successful, %NULL if no frame was available.
*/
@@ -6096,6 +6103,53 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
struct ieee80211_txq *txq);
/**
+ * ieee80211_next_txq - get next tx queue to pull packets from
+ *
+ * @hw: pointer as obtained from ieee80211_alloc_hw()
+ * @ac: AC number to return packets from.
+ *
+ * Should only be called between calls to ieee80211_txq_schedule_start()
+ * and ieee80211_txq_schedule_end().
+ * Returns the next txq if successful, %NULL if no queue is eligible. If a txq
+ * is returned, it should be returned with ieee80211_return_txq() after the
+ * driver has finished scheduling it.
+ */
+struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw, u8 ac);
+
+/**
+ * ieee80211_return_txq - return a TXQ previously acquired by
+ * ieee80211_next_txq()
+ *
+ * @hw: pointer as obtained from ieee80211_alloc_hw()
+ * @txq: pointer obtained from station or virtual interface
+ *
+ * Should only be called between calls to ieee80211_txq_schedule_start()
+ * and ieee80211_txq_schedule_end().
+ */
+void ieee80211_return_txq(struct ieee80211_hw *hw, struct ieee80211_txq *txq);
+
+/**
+ * ieee80211_txq_schedule_start - acquire locks for safe scheduling of an AC
+ *
+ * @hw: pointer as obtained from ieee80211_alloc_hw()
+ * @ac: AC number to acquire locks for
+ *
+ * Acquire locks needed to schedule TXQs from the given AC. Should be called
+ * before ieee80211_next_txq() or ieee80211_return_txq().
+ */
+void ieee80211_txq_schedule_start(struct ieee80211_hw *hw, u8 ac);
+
+/**
+ * ieee80211_txq_schedule_end - release locks for safe scheduling of an AC
+ *
+ * @hw: pointer as obtained from ieee80211_alloc_hw()
+ * @ac: AC number to acquire locks for
+ *
+ * Release locks previously acquired by ieee80211_txq_schedule_end().
+ */
+void ieee80211_txq_schedule_end(struct ieee80211_hw *hw, u8 ac);
+
+/**
* ieee80211_txq_get_depth - get pending frame/byte count of given txq
*
* The values are not guaranteed to be coherent with regard to each other, i.e.
@@ -229,7 +229,7 @@ static void __releases(agg_queue)
clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
local_bh_disable();
rcu_read_lock();
- drv_wake_tx_queue(sta->sdata->local, txqi);
+ schedule_and_wake_txq(sta->sdata->local, txqi);
rcu_read_unlock();
local_bh_enable();
}
@@ -1173,6 +1173,15 @@ static inline void drv_wake_tx_queue(struct ieee80211_local *local,
local->ops->wake_tx_queue(&local->hw, &txq->txq);
}
+static inline void schedule_and_wake_txq(struct ieee80211_local *local,
+ struct txq_info *txqi)
+{
+ spin_lock_bh(&local->active_txq_lock[txqi->txq.ac]);
+ ieee80211_return_txq(&local->hw, &txqi->txq);
+ spin_unlock_bh(&local->active_txq_lock[txqi->txq.ac]);
+ drv_wake_tx_queue(local, txqi);
+}
+
static inline int drv_can_aggregate_in_amsdu(struct ieee80211_local *local,
struct sk_buff *head,
struct sk_buff *skb)
@@ -830,6 +830,8 @@ enum txq_info_flags {
* a fq_flow which is already owned by a different tin
* @def_cvars: codel vars for @def_flow
* @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;
@@ -837,6 +839,8 @@ 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;
unsigned long flags;
/* keep last! */
@@ -1128,6 +1132,11 @@ struct ieee80211_local {
struct codel_vars *cvars;
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];
+
const struct ieee80211_ops *ops;
/*
@@ -663,6 +663,11 @@ struct ieee80211_hw *ieee80211_alloc_hw_nm(size_t priv_data_len,
spin_lock_init(&local->rx_path_lock);
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]);
+ }
+
INIT_LIST_HEAD(&local->chanctx_list);
mutex_init(&local->chanctx_mtx);
@@ -1249,7 +1249,7 @@ void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
if (!sta->sta.txq[i] || !txq_has_queue(sta->sta.txq[i]))
continue;
- drv_wake_tx_queue(local, to_txq_info(sta->sta.txq[i]));
+ schedule_and_wake_txq(local, to_txq_info(sta->sta.txq[i]));
}
skb_queue_head_init(&pending);
@@ -1449,6 +1449,7 @@ 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);
txqi->txq.vif = &sdata->vif;
@@ -1489,6 +1490,9 @@ void ieee80211_txq_purge(struct ieee80211_local *local,
fq_tin_reset(fq, tin, fq_skb_free_func);
ieee80211_purge_tx_queue(&local->hw, &txqi->frags);
+ 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)
@@ -1605,7 +1609,7 @@ static bool ieee80211_queue_skb(struct ieee80211_local *local,
ieee80211_txq_enqueue(local, txqi, skb);
spin_unlock_bh(&fq->lock);
- drv_wake_tx_queue(local, txqi);
+ schedule_and_wake_txq(local, txqi);
return true;
}
@@ -3627,6 +3631,58 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
}
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 txq_info *txqi = NULL;
+
+ lockdep_assert_held(&local->active_txq_lock[ac]);
+
+ txqi = list_first_entry_or_null(&local->active_txqs[ac],
+ struct txq_info,
+ schedule_order);
+
+ if (!txqi || txqi->schedule_round == local->schedule_round[ac])
+ return NULL;
+
+ list_del_init(&txqi->schedule_order);
+ txqi->schedule_round = local->schedule_round[ac];
+ return &txqi->txq;
+}
+EXPORT_SYMBOL(ieee80211_next_txq);
+
+void ieee80211_return_txq(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct txq_info *txqi = to_txq_info(txq);
+
+ lockdep_assert_held(&local->active_txq_lock[txq->ac]);
+
+ if (list_empty(&txqi->schedule_order) &&
+ (!skb_queue_empty(&txqi->frags) || txqi->tin.backlog_packets))
+ list_add_tail(&txqi->schedule_order,
+ &local->active_txqs[txq->ac]);
+}
+EXPORT_SYMBOL(ieee80211_return_txq);
+
+void ieee80211_txq_schedule_start(struct ieee80211_hw *hw, u8 ac)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ spin_lock_bh(&local->active_txq_lock[ac]);
+ local->schedule_round[ac]++;
+}
+EXPORT_SYMBOL(ieee80211_txq_schedule_start);
+
+void ieee80211_txq_schedule_end(struct ieee80211_hw *hw, u8 ac)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ spin_unlock_bh(&local->active_txq_lock[ac]);
+}
+EXPORT_SYMBOL(ieee80211_txq_schedule_end);
+
void __ieee80211_subif_start_xmit(struct sk_buff *skb,
struct net_device *dev,
u32 info_flags)