mac80211: expose txq queue depth and size to drivers

This will allow drivers to make more educated
decisions whether to defer transmission or not.

Relying on wake_tx_queue() call count implicitly
was not possible because it could be called
without queued frame count actually changing on
software tx aggregation start/stop code paths.

It was also not possible to know how long
byte-wise queue was without dequeueing.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Michal Kazior 2016-01-27 15:26:12 +01:00 committed by Johannes Berg
parent dfdfc2beb0
commit f2ac7e301a
6 changed files with 39 additions and 1 deletions

View File

@ -5596,4 +5596,19 @@ void ieee80211_unreserve_tid(struct ieee80211_sta *sta, u8 tid);
*/
struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
struct ieee80211_txq *txq);
/**
* 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.
* txq state can change half-way of this function and the caller may end up
* with "new" frame_cnt and "old" byte_cnt or vice-versa.
*
* @txq: pointer obtained from station or virtual interface
* @frame_cnt: pointer to store frame count
* @byte_cnt: pointer to store byte count
*/
void ieee80211_txq_get_depth(struct ieee80211_txq *txq,
unsigned long *frame_cnt,
unsigned long *byte_cnt);
#endif /* MAC80211_H */

View File

@ -804,6 +804,7 @@ enum txq_info_flags {
struct txq_info {
struct sk_buff_head queue;
unsigned long flags;
unsigned long byte_cnt;
/* keep last! */
struct ieee80211_txq txq;

View File

@ -979,6 +979,7 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
spin_lock_bh(&txqi->queue.lock);
ieee80211_purge_tx_queue(&local->hw, &txqi->queue);
txqi->byte_cnt = 0;
spin_unlock_bh(&txqi->queue.lock);
atomic_set(&sdata->txqs_len[txqi->txq.ac], 0);

View File

@ -116,6 +116,7 @@ static void __cleanup_single_sta(struct sta_info *sta)
ieee80211_purge_tx_queue(&local->hw, &txqi->queue);
atomic_sub(n, &sdata->txqs_len[txqi->txq.ac]);
txqi->byte_cnt = 0;
}
}

View File

@ -1270,7 +1270,11 @@ static void ieee80211_drv_tx(struct ieee80211_local *local,
if (atomic_read(&sdata->txqs_len[ac]) >= local->hw.txq_ac_max_pending)
netif_stop_subqueue(sdata->dev, ac);
skb_queue_tail(&txqi->queue, skb);
spin_lock_bh(&txqi->queue.lock);
txqi->byte_cnt += skb->len;
__skb_queue_tail(&txqi->queue, skb);
spin_unlock_bh(&txqi->queue.lock);
drv_wake_tx_queue(local, txqi);
return;
@ -1298,6 +1302,8 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
if (!skb)
goto out;
txqi->byte_cnt -= skb->len;
atomic_dec(&sdata->txqs_len[ac]);
if (__netif_subqueue_stopped(sdata->dev, ac))
ieee80211_propagate_queue_wake(local, sdata->vif.hw_queue[ac]);

View File

@ -3368,3 +3368,17 @@ void ieee80211_init_tx_queue(struct ieee80211_sub_if_data *sdata,
txqi->txq.ac = IEEE80211_AC_BE;
}
}
void ieee80211_txq_get_depth(struct ieee80211_txq *txq,
unsigned long *frame_cnt,
unsigned long *byte_cnt)
{
struct txq_info *txqi = to_txq_info(txq);
if (frame_cnt)
*frame_cnt = txqi->queue.qlen;
if (byte_cnt)
*byte_cnt = txqi->byte_cnt;
}
EXPORT_SYMBOL(ieee80211_txq_get_depth);