ath10k: move mgmt descriptor limit handle under mgmt_tx

Frames that are transmitted via MGMT_TX are using reserved descriptor
slots in firmware. This limitation is for the htt_mgmt_tx path itself,
not for mgmt frames per se. In 16 MBSSID scenario, these reserved slots
will be easy exhausted due to frequent probe responses. So for 10.4
based solutions, probe responses are limited by a threshold (24).

management tx path is separate for all except tlv based solutions. Since
tlv solutions (qca6174 & qca9377) do not support 16 AP interfaces, it is
safe to move management descriptor limitation check under mgmt_tx
function. Though CPU improvement is negligible, unlikely conditions or
never hit conditions in hot path can be avoided on data transmission.

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/htt.h

@@ -1776,11 +1776,11 @@ void ath10k_htt_tx_txq_update(struct ieee80211_hw *hw,
 void ath10k_htt_tx_txq_recalc(struct ieee80211_hw *hw,
 			      struct ieee80211_txq *txq);
 void ath10k_htt_tx_txq_sync(struct ath10k *ar);
-void ath10k_htt_tx_dec_pending(struct ath10k_htt *htt,
-			       bool is_mgmt);
-int ath10k_htt_tx_inc_pending(struct ath10k_htt *htt,
-			      bool is_mgmt,
-			      bool is_presp);
+void ath10k_htt_tx_dec_pending(struct ath10k_htt *htt);
+int ath10k_htt_tx_inc_pending(struct ath10k_htt *htt);
+void ath10k_htt_tx_mgmt_dec_pending(struct ath10k_htt *htt);
+int ath10k_htt_tx_mgmt_inc_pending(struct ath10k_htt *htt, bool is_mgmt,
+				   bool is_presp);
 
 int ath10k_htt_tx_alloc_msdu_id(struct ath10k_htt *htt, struct sk_buff *skb);
 void ath10k_htt_tx_free_msdu_id(struct ath10k_htt *htt, u16 msdu_id);

drivers/net/wireless/ath/ath10k/htt_rx.c

@@ -2354,7 +2354,12 @@ void ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb)
 			break;
 		}
 
-		ath10k_txrx_tx_unref(htt, &tx_done);
+		status = ath10k_txrx_tx_unref(htt, &tx_done);
+		if (!status) {
+			spin_lock_bh(&htt->tx_lock);
+			ath10k_htt_tx_mgmt_dec_pending(htt);
+			spin_unlock_bh(&htt->tx_lock);
+		}
 		ath10k_mac_tx_push_pending(ar);
 		break;
 	}

drivers/net/wireless/ath/ath10k/htt_tx.c

@@ -149,39 +149,22 @@ void ath10k_htt_tx_txq_update(struct ieee80211_hw *hw,
 	spin_unlock_bh(&ar->htt.tx_lock);
 }
 
-void ath10k_htt_tx_dec_pending(struct ath10k_htt *htt,
-			       bool is_mgmt)
+void ath10k_htt_tx_dec_pending(struct ath10k_htt *htt)
 {
 	lockdep_assert_held(&htt->tx_lock);
 
-	if (is_mgmt)
-		htt->num_pending_mgmt_tx--;
-
 	htt->num_pending_tx--;
 	if (htt->num_pending_tx == htt->max_num_pending_tx - 1)
 		ath10k_mac_tx_unlock(htt->ar, ATH10K_TX_PAUSE_Q_FULL);
 }
 
-int ath10k_htt_tx_inc_pending(struct ath10k_htt *htt,
-			      bool is_mgmt,
-			      bool is_presp)
+int ath10k_htt_tx_inc_pending(struct ath10k_htt *htt)
 {
-	struct ath10k *ar = htt->ar;
-
 	lockdep_assert_held(&htt->tx_lock);
 
 	if (htt->num_pending_tx >= htt->max_num_pending_tx)
 		return -EBUSY;
 
-	if (is_mgmt &&
-	    is_presp &&
-	    ar->hw_params.max_probe_resp_desc_thres &&
-	    ar->hw_params.max_probe_resp_desc_thres < htt->num_pending_mgmt_tx)
-		return -EBUSY;
-
-	if (is_mgmt)
-		htt->num_pending_mgmt_tx++;
-
 	htt->num_pending_tx++;
 	if (htt->num_pending_tx == htt->max_num_pending_tx)
 		ath10k_mac_tx_lock(htt->ar, ATH10K_TX_PAUSE_Q_FULL);
@@ -189,6 +172,35 @@ int ath10k_htt_tx_inc_pending(struct ath10k_htt *htt,
 	return 0;
 }
 
+int ath10k_htt_tx_mgmt_inc_pending(struct ath10k_htt *htt, bool is_mgmt,
+				   bool is_presp)
+{
+	struct ath10k *ar = htt->ar;
+
+	lockdep_assert_held(&htt->tx_lock);
+
+	if (!is_mgmt || !ar->hw_params.max_probe_resp_desc_thres)
+		return 0;
+
+	if (is_presp &&
+	    ar->hw_params.max_probe_resp_desc_thres < htt->num_pending_mgmt_tx)
+		return -EBUSY;
+
+	htt->num_pending_mgmt_tx++;
+
+	return 0;
+}
+
+void ath10k_htt_tx_mgmt_dec_pending(struct ath10k_htt *htt)
+{
+	lockdep_assert_held(&htt->tx_lock);
+
+	if (!htt->ar->hw_params.max_probe_resp_desc_thres)
+		return;
+
+	htt->num_pending_mgmt_tx--;
+}
+
 int ath10k_htt_tx_alloc_msdu_id(struct ath10k_htt *htt, struct sk_buff *skb)
 {
 	struct ath10k *ar = htt->ar;

drivers/net/wireless/ath/ath10k/mac.c

@@ -3699,8 +3699,6 @@ static bool ath10k_mac_tx_can_push(struct ieee80211_hw *hw,
 int ath10k_mac_tx_push_txq(struct ieee80211_hw *hw,
 			   struct ieee80211_txq *txq)
 {
-	const bool is_mgmt = false;
-	const bool is_presp = false;
 	struct ath10k *ar = hw->priv;
 	struct ath10k_htt *htt = &ar->htt;
 	struct ath10k_txq *artxq = (void *)txq->drv_priv;
@@ -3713,7 +3711,7 @@ int ath10k_mac_tx_push_txq(struct ieee80211_hw *hw,
 	int ret;
 
 	spin_lock_bh(&ar->htt.tx_lock);
-	ret = ath10k_htt_tx_inc_pending(htt, is_mgmt, is_presp);
+	ret = ath10k_htt_tx_inc_pending(htt);
 	spin_unlock_bh(&ar->htt.tx_lock);
 
 	if (ret)
@@ -3722,7 +3720,7 @@ int ath10k_mac_tx_push_txq(struct ieee80211_hw *hw,
 	skb = ieee80211_tx_dequeue(hw, txq);
 	if (!skb) {
 		spin_lock_bh(&ar->htt.tx_lock);
-		ath10k_htt_tx_dec_pending(htt, is_mgmt);
+		ath10k_htt_tx_dec_pending(htt);
 		spin_unlock_bh(&ar->htt.tx_lock);
 
 		return -ENOENT;
@@ -3739,7 +3737,7 @@ int ath10k_mac_tx_push_txq(struct ieee80211_hw *hw,
 		ath10k_warn(ar, "failed to push frame: %d\n", ret);
 
 		spin_lock_bh(&ar->htt.tx_lock);
-		ath10k_htt_tx_dec_pending(htt, is_mgmt);
+		ath10k_htt_tx_dec_pending(htt);
 		spin_unlock_bh(&ar->htt.tx_lock);
 
 		return ret;
@@ -3978,14 +3976,13 @@ static void ath10k_mac_op_tx(struct ieee80211_hw *hw,
 	txpath = ath10k_mac_tx_h_get_txpath(ar, skb, txmode);
 	is_htt = (txpath == ATH10K_MAC_TX_HTT ||
 		  txpath == ATH10K_MAC_TX_HTT_MGMT);
+	is_mgmt = (txpath == ATH10K_MAC_TX_HTT_MGMT);
 
 	if (is_htt) {
 		spin_lock_bh(&ar->htt.tx_lock);
-
-		is_mgmt = ieee80211_is_mgmt(hdr->frame_control);
 		is_presp = ieee80211_is_probe_resp(hdr->frame_control);
 
-		ret = ath10k_htt_tx_inc_pending(htt, is_mgmt, is_presp);
+		ret = ath10k_htt_tx_inc_pending(htt);
 		if (ret) {
 			ath10k_warn(ar, "failed to increase tx pending count: %d, dropping\n",
 				    ret);
@@ -3994,6 +3991,15 @@ static void ath10k_mac_op_tx(struct ieee80211_hw *hw,
 			return;
 		}
 
+		ret = ath10k_htt_tx_mgmt_inc_pending(htt, is_mgmt, is_presp);
+		if (ret) {
+			ath10k_warn(ar, "failed to increase tx mgmt pending count: %d, dropping\n",
+				    ret);
+			ath10k_htt_tx_dec_pending(htt);
+			spin_unlock_bh(&ar->htt.tx_lock);
+			ieee80211_free_txskb(ar->hw, skb);
+			return;
+		}
 		spin_unlock_bh(&ar->htt.tx_lock);
 	}
 
@@ -4002,7 +4008,9 @@ static void ath10k_mac_op_tx(struct ieee80211_hw *hw,
 		ath10k_warn(ar, "failed to transmit frame: %d\n", ret);
 		if (is_htt) {
 			spin_lock_bh(&ar->htt.tx_lock);
-			ath10k_htt_tx_dec_pending(htt, is_mgmt);
+			ath10k_htt_tx_dec_pending(htt);
+			if (is_mgmt)
+				ath10k_htt_tx_mgmt_dec_pending(htt);
 			spin_unlock_bh(&ar->htt.tx_lock);
 		}
 		return;

drivers/net/wireless/ath/ath10k/txrx.c

@@ -49,8 +49,8 @@ out:
 	spin_unlock_bh(&ar->data_lock);
 }
 
-void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
-			  const struct htt_tx_done *tx_done)
+int ath10k_txrx_tx_unref(struct ath10k_htt *htt,
+			 const struct htt_tx_done *tx_done)
 {
 	struct ath10k *ar = htt->ar;
 	struct device *dev = ar->dev;
@@ -59,7 +59,6 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
 	struct ath10k_skb_cb *skb_cb;
 	struct ath10k_txq *artxq;
 	struct sk_buff *msdu;
-	bool limit_mgmt_desc = false;
 
 	ath10k_dbg(ar, ATH10K_DBG_HTT,
 		   "htt tx completion msdu_id %u discard %d no_ack %d success %d\n",
@@ -69,7 +68,7 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
 	if (tx_done->msdu_id >= htt->max_num_pending_tx) {
 		ath10k_warn(ar, "warning: msdu_id %d too big, ignoring\n",
 			    tx_done->msdu_id);
-		return;
+		return -EINVAL;
 	}
 
 	spin_lock_bh(&htt->tx_lock);
@@ -78,22 +77,18 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
 		ath10k_warn(ar, "received tx completion for invalid msdu_id: %d\n",
 			    tx_done->msdu_id);
 		spin_unlock_bh(&htt->tx_lock);
-		return;
+		return -ENOENT;
 	}
 
 	skb_cb = ATH10K_SKB_CB(msdu);
 	txq = skb_cb->txq;
 	artxq = (void *)txq->drv_priv;
 
-	if (unlikely(skb_cb->flags & ATH10K_SKB_F_MGMT) &&
-	    ar->hw_params.max_probe_resp_desc_thres)
-		limit_mgmt_desc = true;
-
 	if (txq)
 		artxq->num_fw_queued--;
 
 	ath10k_htt_tx_free_msdu_id(htt, tx_done->msdu_id);
-	ath10k_htt_tx_dec_pending(htt, limit_mgmt_desc);
+	ath10k_htt_tx_dec_pending(htt);
 	if (htt->num_pending_tx == 0)
 		wake_up(&htt->empty_tx_wq);
 	spin_unlock_bh(&htt->tx_lock);
@@ -108,7 +103,7 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
 
 	if (tx_done->discard) {
 		ieee80211_free_txskb(htt->ar->hw, msdu);
-		return;
+		return 0;
 	}
 
 	if (!(info->flags & IEEE80211_TX_CTL_NO_ACK))
@@ -122,6 +117,7 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
 
 	ieee80211_tx_status(htt->ar->hw, msdu);
 	/* we do not own the msdu anymore */
+	return 0;
 }
 
 struct ath10k_peer *ath10k_peer_find(struct ath10k *ar, int vdev_id,

drivers/net/wireless/ath/ath10k/txrx.h

@@ -19,8 +19,8 @@
 
 #include "htt.h"
 
-void ath10k_txrx_tx_unref(struct ath10k_htt *htt,
-			  const struct htt_tx_done *tx_done);
+int ath10k_txrx_tx_unref(struct ath10k_htt *htt,
+			 const struct htt_tx_done *tx_done);
 
 struct ath10k_peer *ath10k_peer_find(struct ath10k *ar, int vdev_id,
 				     const u8 *addr);