From 1866760096bf40bcf6977a9076b3026598bc12ee Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Tue, 18 Dec 2018 17:02:06 -0800 Subject: mac80211: Add TXQ scheduling API MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds an API to mac80211 to handle scheduling of TXQs. The interface between driver and mac80211 for TXQ handling is changed by adding two new functions: ieee80211_next_txq(), which will return the next TXQ to schedule in the current round-robin rotation, and ieee80211_return_txq(), which the driver uses to indicate that it has finished scheduling a TXQ (which will then be put back in the scheduling rotation if it isn't empty). The driver must call ieee80211_txq_schedule_start() at the start of each scheduling session, and ieee80211_txq_schedule_end() at the end. The API then guarantees that the same TXQ is not returned twice in the same session (so a driver can loop on ieee80211_next_txq() without worrying about breaking the loop. Usage of the new API is optional, so drivers can be ported one at a time. In this patch, the actual scheduling performed by mac80211 is simple round-robin, but a subsequent commit adds airtime fairness awareness to the scheduler. Signed-off-by: Toke Høiland-Jørgensen [minor kernel-doc fix, propagate sparse locking checks out] Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 59 insertions(+), 1 deletion(-) (limited to 'net/mac80211/tx.c') diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index f170d6c6629a..544da6411620 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -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; } @@ -3630,6 +3634,60 @@ out: } 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) + __acquires(txq_lock) +{ + 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) + __releases(txq_lock) +{ + 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) -- cgit v1.2.3-70-g09d2