On 2018-09-10 04:13, Toke Høiland-Jørgensen wrote:

Johannes Berg [off-list ref] writes:

quoted

quoted

-			       txqi->flags & (1<<IEEE80211_TXQ_STOP) ? "STOP" : "RUN",
-			       txqi->flags & (1<<IEEE80211_TXQ_AMPDU) ? " AMPDU" : "",
-			       txqi->flags & (1<<IEEE80211_TXQ_NO_AMSDU) ? " NO-AMSDU" : 
"");
+			       txqi->flags & (1 << IEEE80211_TXQ_STOP) ? "STOP" : "RUN",
+			       txqi->flags & (1 << IEEE80211_TXQ_AMPDU) ? " AMPDU" : "",
+			       txqi->flags & (1 << IEEE80211_TXQ_NO_AMSDU) ? " NO-AMSDU" 
: "");

consider BIT() instead as a cleanup? :)

(or maybe this is just a leftover from merging some other patches?)

Yeah, this is a merging artifact; Rajkumar's patch added another flag,
that I removed again. Didn't notice that there was still a whitespace
change in this patch...

I added the flag based on our last discussion. The driver needs to check
txq status for each tx_dequeue(). One time txq check is not sufficient
as it allows the driver to dequeue all frames from txq.

drv_func() {
       while (ieee80211_airtime_may_transmit(txq) &&
               hw_has_space() &&
              (pkt = ieee80211_tx_dequeue(hw, txq)))
           push_to_hw(pkt);
}

quoted

quoted

+bool ieee80211_txq_may_transmit(struct ieee80211_hw *hw,
+				struct ieee80211_txq *txq)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+	struct txq_info *txqi = to_txq_info(txq);
+	bool may_tx = false;
+
+	spin_lock_bh(&local->active_txq_lock);
+
+	if (ieee80211_txq_check_deficit(local, txqi)) {
+		may_tx = true;
+		list_del_init(&txqi->schedule_order);

To handle above case, may_transmit should remove the node only
when it is in list.

if (list_empty(&txqi->schedule_order))
        list_del_init(&txqi->schedule_order);

So that it can be used to determine whether txq is running negative.

-Rajkumar