txqs_lock is interfering with wake_tx_queue submitting more frames.
so queues don't get filled in and don't keep firmware/hardware busy
enough. This change helps to reduce the txqs_lock contention and
wake_tx_queue() blockage to being possible in txrx_unref().
To reduce turn around time of wake_tx_queue ops and to maintain fairness
among all txqs, the callback is updated to push first txq alone from
pending list for every wake_tx_queue call. Remaining txqs will be
processed later upon tx completion.
Below improvements are observed in push-only mode and validated on
IPQ4019 platform. With this change, in AP mode ~10Mbps increase is
observed in downlink (AP -> STA) traffic and approx. 5-10% of CPU
usage is reduced.
Major improvement is observed in 1-hop Mesh mode topology in 11ACVHT80.
Compared to Infra mode, CPU overhead is higher in Mesh mode due to path
lookup and no fast-xmit support. So reducing spin lock contention is
helping in Mesh.
TOT +change
-------- --------
TCP DL 545 Mbps 595 Mbps
TCP UL 555 Mbps 585 Mbps
Signed-off-by: Rajkumar Manoharan <rmanohar@xxxxxxxxxxxxxxxx>
---
drivers/net/wireless/ath/ath10k/mac.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index c7c7ceb9be73..93465ffec2eb 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -4106,13 +4106,29 @@ static void ath10k_mac_op_wake_tx_queue(struct ieee80211_hw *hw,
{
struct ath10k *ar = hw->priv;
struct ath10k_txq *artxq = (void *)txq->drv_priv;
+ struct ieee80211_txq *f_txq;
+ struct ath10k_txq *f_artxq;
+ int ret = 0;
+ int max = 16;
spin_lock_bh(&ar->txqs_lock);
if (list_empty(&artxq->list))
list_add_tail(&artxq->list, &ar->txqs);
+
+ f_artxq = list_first_entry(&ar->txqs, struct ath10k_txq, list);
+ f_txq = container_of((void *)f_artxq, struct ieee80211_txq, drv_priv);
+ list_del_init(&f_artxq->list);
+
+ while (ath10k_mac_tx_can_push(hw, f_txq) && max--) {
+ ret = ath10k_mac_tx_push_txq(hw, f_txq);
+ if (ret)
+ break;
+ }
+ if (ret != -ENOENT)
+ list_add_tail(&f_artxq->list, &ar->txqs);
spin_unlock_bh(&ar->txqs_lock);
- ath10k_mac_tx_push_pending(ar);
+ ath10k_htt_tx_txq_update(hw, f_txq);
ath10k_htt_tx_txq_update(hw, txq);
}
--
2.9.2
