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: Alexander Wetzel <alexander@wetzel-home.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Alexander Wetzel 2022-10-09 18:30:38 +02:00 committed by Johannes Berg
parent 0ff57171d6
commit c850e31f79
2 changed files with 78 additions and 19 deletions

View File

@ -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
*

View File

@ -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;