Commit c850e31f authored by Alexander Wetzel's avatar Alexander Wetzel Committed by Johannes Berg
Browse files

wifi: mac80211: add internal handler for wake_tx_queue 



Start to align the TX handling to only use internal TX queues (iTXQs):

Provide a handler for drivers not having a custom wake_tx_queue
callback and update the documentation.

Signed-off-by: default avatarAlexander Wetzel <alexander@wetzel-home.de>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 0ff57171

include/net/mac80211.h

+32 −19
Original line number Diff line number Diff line
@@ -89,15 +89,13 @@ 
/**

 * DOC: mac80211 software tx queueing

 *

 * mac80211 provides an optional intermediate queueing implementation designed

 * to allow the driver to keep hardware queues short and provide some fairness

 * between different stations/interfaces.

 * In this model, the driver pulls data frames from the mac80211 queue instead

 * of letting mac80211 push them via drv_tx().

 * Other frames (e.g. control or management) are still pushed using drv_tx().

 * mac80211 uses an intermediate queueing implementation, designed to allow the

 * driver to keep hardware queues short and to provide some fairness between

 * different stations/interfaces.

 *

 * Drivers indicate that they use this model by implementing the .wake_tx_queue

 * driver operation.

 * Drivers must provide the .wake_tx_queue driver operation by either

 * linking it to ieee80211_handle_wake_tx_queue() or implementing a custom

 * handler.

 *

 * Intermediate queues (struct ieee80211_txq) are kept per-sta per-tid, with

 * another per-sta for non-data/non-mgmt and bufferable management frames, and
@@ -106,9 +104,12 @@ 
 * 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 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.

 * The driver can't access the internal TX queues (iTXQs) directly.

 * Whenever mac80211 adds a new frame to a queue, it calls the .wake_tx_queue

 * driver op.

 * Drivers implementing a custom .wake_tx_queue op can get them by calling

 * ieee80211_tx_dequeue(). Drivers using ieee80211_handle_wake_tx_queue() will

 * simply get the individual frames pushed via the .tx driver operation.

 *

 * Drivers can optionally delegate responsibility for scheduling queues to

 * mac80211, to take advantage of airtime fairness accounting. In this case, to
@@ -1826,7 +1827,7 @@ struct ieee80211_vif_cfg { 
 *	for this interface.

 * @drv_priv: data area for driver use, will always be aligned to

 *	sizeof(void \*).

 * @txq: the multicast data TX queue (if driver uses the TXQ abstraction)

 * @txq: the multicast data TX queue

 * @txqs_stopped: per AC flag to indicate that intermediate TXQs are stopped,

 *	protected by fq->lock.

 * @offload_flags: 802.3 -> 802.11 enapsulation offload flags, see
@@ -2259,8 +2260,8 @@ struct ieee80211_link_sta { 
 *	For non MLO STA it will point to the deflink data. For MLO STA

 *	ieee80211_sta_recalc_aggregates() must be called to update it.

 * @support_p2p_ps: indicates whether the STA supports P2P PS mechanism or not.

 * @txq: per-TID data TX queues (if driver uses the TXQ abstraction); note that

 *	the last entry (%IEEE80211_NUM_TIDS) is used for non-data frames

 * @txq: per-TID data TX queues; note that the last entry (%IEEE80211_NUM_TIDS)

 *	is used for non-data frames

 * @deflink: This holds the default link STA information, for non MLO STA all link

 *	specific STA information is accessed through @deflink or through

 *	link[0] which points to address of @deflink. For MLO Link STA
@@ -5713,7 +5714,7 @@ void ieee80211_key_replay(struct ieee80211_key_conf *keyconf); 
 * @hw: pointer as obtained from ieee80211_alloc_hw().

 * @queue: queue number (counted from zero).

 *

 * Drivers should use this function instead of netif_wake_queue.

 * Drivers must use this function instead of netif_wake_queue.

 */

void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue);
@@ -5722,7 +5723,7 @@ void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue); 
 * @hw: pointer as obtained from ieee80211_alloc_hw().

 * @queue: queue number (counted from zero).

 *

 * Drivers should use this function instead of netif_stop_queue.

 * Drivers must use this function instead of netif_stop_queue.

 */

void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue);
@@ -5731,7 +5732,7 @@ void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue); 
 * @hw: pointer as obtained from ieee80211_alloc_hw().

 * @queue: queue number (counted from zero).

 *

 * Drivers should use this function instead of netif_stop_queue.

 * Drivers must use this function instead of netif_queue_stopped.

 *

 * Return: %true if the queue is stopped. %false otherwise.

 */
@@ -5742,7 +5743,7 @@ int ieee80211_queue_stopped(struct ieee80211_hw *hw, int queue); 
 * ieee80211_stop_queues - stop all queues

 * @hw: pointer as obtained from ieee80211_alloc_hw().

 *

 * Drivers should use this function instead of netif_stop_queue.

 * Drivers must use this function instead of netif_tx_stop_all_queues.

 */

void ieee80211_stop_queues(struct ieee80211_hw *hw);
@@ -5750,7 +5751,7 @@ void ieee80211_stop_queues(struct ieee80211_hw *hw); 
 * ieee80211_wake_queues - wake all queues

 * @hw: pointer as obtained from ieee80211_alloc_hw().

 *

 * Drivers should use this function instead of netif_wake_queue.

 * Drivers must use this function instead of netif_tx_wake_all_queues.

 */

void ieee80211_wake_queues(struct ieee80211_hw *hw);
@@ -6971,6 +6972,18 @@ static inline struct sk_buff *ieee80211_tx_dequeue_ni(struct ieee80211_hw *hw, 
	return skb;

}



/**

 * ieee80211_handle_wake_tx_queue - mac80211 handler for wake_tx_queue callback

 *

 * @hw: pointer as obtained from wake_tx_queue() callback().

 * @txq: pointer as obtained from wake_tx_queue() callback().

 *

 * Drivers can use this function for the mandatory mac80211 wake_tx_queue

 * callback in struct ieee80211_ops. They should not call this function.

 */

void ieee80211_handle_wake_tx_queue(struct ieee80211_hw *hw,

				    struct ieee80211_txq *txq);



/**

 * ieee80211_next_txq - get next tx queue to pull packets from

 *

net/mac80211/util.c

+46 −0
Original line number Diff line number Diff line
@@ -288,6 +288,52 @@ __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, 
}

EXPORT_SYMBOL(ieee80211_ctstoself_duration);



static void wake_tx_push_queue(struct ieee80211_local *local,

			       struct ieee80211_sub_if_data *sdata,

			       struct ieee80211_txq *queue)

{

	int q = sdata->vif.hw_queue[queue->ac];

	struct ieee80211_tx_control control = {

		.sta = queue->sta,

	};

	struct sk_buff *skb;

	unsigned long flags;

	bool q_stopped;



	while (1) {

		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);

		q_stopped = local->queue_stop_reasons[q];

		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);



		if (q_stopped)

			break;



		skb = ieee80211_tx_dequeue(&local->hw, queue);

		if (!skb)

			break;



		drv_tx(local, &control, skb);

	}

}



/* wake_tx_queue handler for driver not implementing a custom one*/

void ieee80211_handle_wake_tx_queue(struct ieee80211_hw *hw,

				    struct ieee80211_txq *txq)

{

	struct ieee80211_local *local = hw_to_local(hw);

	struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);

	struct ieee80211_txq *queue;



	/* Use ieee80211_next_txq() for airtime fairness accounting */

	ieee80211_txq_schedule_start(hw, txq->ac);

	while ((queue = ieee80211_next_txq(hw, txq->ac))) {

		wake_tx_push_queue(local, sdata, queue);

		ieee80211_return_txq(hw, queue, false);

	}

	ieee80211_txq_schedule_end(hw, txq->ac);

}

EXPORT_SYMBOL(ieee80211_handle_wake_tx_queue);



static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac)

{

	struct ieee80211_local *local = sdata->local;