diff options
Diffstat (limited to 'package/kernel/mac80211/patches/subsys/320-mac80211-Add-TXQ-scheduling-API.patch')
| -rw-r--r-- | package/kernel/mac80211/patches/subsys/320-mac80211-Add-TXQ-scheduling-API.patch | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/package/kernel/mac80211/patches/subsys/320-mac80211-Add-TXQ-scheduling-API.patch b/package/kernel/mac80211/patches/subsys/320-mac80211-Add-TXQ-scheduling-API.patch new file mode 100644 index 0000000000..0f7d9e1506 --- /dev/null +++ b/package/kernel/mac80211/patches/subsys/320-mac80211-Add-TXQ-scheduling-API.patch @@ -0,0 +1,292 @@ +From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk> +Date: Tue, 18 Dec 2018 17:02:06 -0800 +Subject: [PATCH] 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 <toke@toke.dk> +[minor kernel-doc fix, propagate sparse locking checks out] +Signed-off-by: Johannes Berg <johannes.berg@intel.com> +--- + +--- a/include/net/mac80211.h ++++ b/include/net/mac80211.h +@@ -107,9 +107,15 @@ + * 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 +@@ -5979,7 +5985,8 @@ void ieee80211_unreserve_tid(struct ieee + * 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. + */ +@@ -5987,6 +5994,54 @@ struct sk_buff *ieee80211_tx_dequeue(str + 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) ++ __acquires(txq_lock); ++ ++/** ++ * 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) ++ __releases(txq_lock); ++ ++/** + * 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. +--- a/net/mac80211/agg-tx.c ++++ b/net/mac80211/agg-tx.c +@@ -229,7 +229,7 @@ ieee80211_agg_start_txq(struct sta_info + 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(); + } +--- a/net/mac80211/driver-ops.h ++++ b/net/mac80211/driver-ops.h +@@ -1176,6 +1176,15 @@ static inline void drv_wake_tx_queue(str + 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_start_nan(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + struct cfg80211_nan_conf *conf) +--- a/net/mac80211/ieee80211_i.h ++++ b/net/mac80211/ieee80211_i.h +@@ -829,6 +829,8 @@ 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; +@@ -836,6 +838,8 @@ 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! */ +@@ -1127,6 +1131,11 @@ 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; + + /* +--- a/net/mac80211/main.c ++++ b/net/mac80211/main.c +@@ -652,6 +652,11 @@ struct ieee80211_hw *ieee80211_alloc_hw_ + 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); + +--- a/net/mac80211/sta_info.c ++++ b/net/mac80211/sta_info.c +@@ -1244,7 +1244,7 @@ void ieee80211_sta_ps_deliver_wakeup(str + if (!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])); + } + } + +--- a/net/mac80211/tx.c ++++ b/net/mac80211/tx.c +@@ -1441,6 +1441,7 @@ void ieee80211_txq_init(struct ieee80211 + 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; + +@@ -1464,6 +1465,9 @@ void ieee80211_txq_purge(struct ieee8021 + + 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) +@@ -1580,7 +1584,7 @@ static bool ieee80211_queue_skb(struct i + 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; + } +@@ -3602,6 +3606,60 @@ 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) |