wl12xx: start/stop queues according to global per-AC counters

Split tx_queue_count to count per-AC skb's queued, instead of relying on
the skb-queue len. The skb queues used were only valid in STA-mode, as
AP-mode uses per-link queues.

This fixes a major regression in AP-mode, caused by the patch
"wl12xx: implement Tx watermarks per AC". With that patch applied, we
effectively had no regulation of Tx queues in AP-mode. Therefore a
sustained high rate of Tx could cause exhaustion of the skb memory pool.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c
index 526b1ac2dd80..e58c22d21e39 100644
--- a/drivers/net/wireless/wl12xx/main.c
+++ b/drivers/net/wireless/wl12xx/main.c
@@ -992,7 +992,7 @@ irqreturn_t wl1271_irq(int irq, void *cookie)
 			/* Check if any tx blocks were freed */
 			spin_lock_irqsave(&wl->wl_lock, flags);
 			if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags) &&
-			    wl->tx_queue_count) {
+			    wl1271_tx_total_queue_count(wl) > 0) {
 				spin_unlock_irqrestore(&wl->wl_lock, flags);
 				/*
 				 * In order to avoid starvation of the TX path,
@@ -1040,7 +1040,7 @@ out:
 	/* In case TX was not handled here, queue TX work */
 	clear_bit(WL1271_FLAG_TX_PENDING, &wl->flags);
 	if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags) &&
-	    wl->tx_queue_count)
+	    wl1271_tx_total_queue_count(wl) > 0)
 		ieee80211_queue_work(wl->hw, &wl->tx_work);
 	spin_unlock_irqrestore(&wl->wl_lock, flags);
 
@@ -1508,13 +1508,13 @@ static void wl1271_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 
 	spin_lock_irqsave(&wl->wl_lock, flags);
 
-	wl->tx_queue_count++;
+	wl->tx_queue_count[q]++;
 
 	/*
 	 * The workqueue is slow to process the tx_queue and we need stop
 	 * the queue here, otherwise the queue will get too long.
 	 */
-	if (skb_queue_len(&wl->tx_queue[q]) >= WL1271_TX_QUEUE_HIGH_WATERMARK) {
+	if (wl->tx_queue_count[q] >= WL1271_TX_QUEUE_HIGH_WATERMARK) {
 		wl1271_debug(DEBUG_TX, "op_tx: stopping queues for q %d", q);
 		ieee80211_stop_queue(wl->hw, mapping);
 		set_bit(q, &wl->stopped_queues_map);
@@ -1543,10 +1543,11 @@ static void wl1271_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 int wl1271_tx_dummy_packet(struct wl1271 *wl)
 {
 	unsigned long flags;
+	int q = wl1271_tx_get_queue(skb_get_queue_mapping(wl->dummy_packet));
 
 	spin_lock_irqsave(&wl->wl_lock, flags);
 	set_bit(WL1271_FLAG_DUMMY_PACKET_PENDING, &wl->flags);
-	wl->tx_queue_count++;
+	wl->tx_queue_count[q]++;
 	spin_unlock_irqrestore(&wl->wl_lock, flags);
 
 	/* The FW is low on RX memory blocks, so send the dummy packet asap */
@@ -3752,7 +3753,7 @@ static bool wl1271_tx_frames_pending(struct ieee80211_hw *hw)
 		goto out;
 
 	/* packets are considered pending if in the TX queue or the FW */
-	ret = (wl->tx_queue_count > 0) || (wl->tx_frames_cnt > 0);
+	ret = (wl1271_tx_total_queue_count(wl) > 0) || (wl->tx_frames_cnt > 0);
 
 	/* the above is appropriate for STA mode for PS purposes */
 	WARN_ON(wl->bss_type != BSS_TYPE_STA_BSS);