wl12xx: Change TX queue to be per AC

With the current single-queue implementation traffic priorization is not
working correctly - when using multiple BE streams and one, say VI stream,
the VI stream will share bandwidth almost equally with the BE streams.

To fix the issue, implement per AC queues, which are emptied in priority
order to the firmware. To keep it relatively simple, maintain a global
buffer count and global queue stop/wake instead of per-AC.

With these changes, priorization appears to work just fine.

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>

1 files changed, 49 insertions, 11 deletions

diff --git a/drivers/net/wireless/wl12xx/tx.c b/drivers/net/wireless/wl12xx/tx.c
index d332b3f6d0f..b44c75cd8c1 100644
--- a/drivers/net/wireless/wl12xx/tx.c
+++ b/drivers/net/wireless/wl12xx/tx.c
@@ -125,7 +125,6 @@ static void wl1271_tx_fill_hdr(struct wl1271 *wl, struct sk_buff *skb,
 	/* queue (we use same identifiers for tid's and ac's */
 	ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 	desc->tid = ac;
-
 	desc->aid = TX_HW_DEFAULT_AID;
 	desc->reserved = 0;
 
@@ -228,7 +227,7 @@ static void handle_tx_low_watermark(struct wl1271 *wl)
 	unsigned long flags;
 
 	if (test_bit(WL1271_FLAG_TX_QUEUE_STOPPED, &wl->flags) &&
-	    skb_queue_len(&wl->tx_queue) <= WL1271_TX_QUEUE_LOW_WATERMARK) {
+	    wl->tx_queue_count <= WL1271_TX_QUEUE_LOW_WATERMARK) {
 		/* firmware buffer has space, restart queues */
 		spin_lock_irqsave(&wl->wl_lock, flags);
 		ieee80211_wake_queues(wl->hw);
@@ -237,6 +236,43 @@ static void handle_tx_low_watermark(struct wl1271 *wl)
 	}
 }
 
+static struct sk_buff *wl1271_skb_dequeue(struct wl1271 *wl)
+{
+	struct sk_buff *skb = NULL;
+	unsigned long flags;
+
+	skb = skb_dequeue(&wl->tx_queue[CONF_TX_AC_VO]);
+	if (skb)
+		goto out;
+	skb = skb_dequeue(&wl->tx_queue[CONF_TX_AC_VI]);
+	if (skb)
+		goto out;
+	skb = skb_dequeue(&wl->tx_queue[CONF_TX_AC_BE]);
+	if (skb)
+		goto out;
+	skb = skb_dequeue(&wl->tx_queue[CONF_TX_AC_BK]);
+
+out:
+	if (skb) {
+		spin_lock_irqsave(&wl->wl_lock, flags);
+		wl->tx_queue_count--;
+		spin_unlock_irqrestore(&wl->wl_lock, flags);
+	}
+
+	return skb;
+}
+
+static void wl1271_skb_queue_head(struct wl1271 *wl, struct sk_buff *skb)
+{
+	unsigned long flags;
+	int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
+
+	skb_queue_head(&wl->tx_queue[q], skb);
+	spin_lock_irqsave(&wl->wl_lock, flags);
+	wl->tx_queue_count++;
+	spin_unlock_irqrestore(&wl->wl_lock, flags);
+}
+
 void wl1271_tx_work_locked(struct wl1271 *wl)
 {
 	struct sk_buff *skb;
@@ -270,7 +306,7 @@ void wl1271_tx_work_locked(struct wl1271 *wl)
 		wl1271_acx_rate_policies(wl);
 	}
 
-	while ((skb = skb_dequeue(&wl->tx_queue))) {
+	while ((skb = wl1271_skb_dequeue(wl))) {
 		if (!woken_up) {
 			ret = wl1271_ps_elp_wakeup(wl, false);
 			if (ret < 0)
@@ -284,9 +320,9 @@ void wl1271_tx_work_locked(struct wl1271 *wl)
 			 * Aggregation buffer is full.
 			 * Flush buffer and try again.
 			 */
-			skb_queue_head(&wl->tx_queue, skb);
+			wl1271_skb_queue_head(wl, skb);
 			wl1271_write(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
-				buf_offset, true);
+				     buf_offset, true);
 			sent_packets = true;
 			buf_offset = 0;
 			continue;
@@ -295,7 +331,7 @@ void wl1271_tx_work_locked(struct wl1271 *wl)
 			 * Firmware buffer is full.
 			 * Queue back last skb, and stop aggregating.
 			 */
-			skb_queue_head(&wl->tx_queue, skb);
+			wl1271_skb_queue_head(wl, skb);
 			/* No work left, avoid scheduling redundant tx work */
 			set_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags);
 			goto out_ack;
@@ -440,10 +476,13 @@ void wl1271_tx_reset(struct wl1271 *wl)
 	struct sk_buff *skb;
 
 	/* TX failure */
-	while ((skb = skb_dequeue(&wl->tx_queue))) {
-		wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
-		ieee80211_tx_status(wl->hw, skb);
+	for (i = 0; i < NUM_TX_QUEUES; i++) {
+		while ((skb = skb_dequeue(&wl->tx_queue[i]))) {
+			wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
+			ieee80211_tx_status(wl->hw, skb);
+		}
 	}
+	wl->tx_queue_count = 0;
 
 	/*
 	 * Make sure the driver is at a consistent state, in case this
@@ -472,8 +511,7 @@ void wl1271_tx_flush(struct wl1271 *wl)
 		mutex_lock(&wl->mutex);
 		wl1271_debug(DEBUG_TX, "flushing tx buffer: %d",
 			     wl->tx_frames_cnt);
-		if ((wl->tx_frames_cnt == 0) &&
-		    skb_queue_empty(&wl->tx_queue)) {
+		if ((wl->tx_frames_cnt == 0) && (wl->tx_queue_count == 0)) {
 			mutex_unlock(&wl->mutex);
 			return;
 		}