[PATCH 1/9] mt76: usb: fix use of q->head and q->tail

Felix Fietkau
2020-08-31T12:26:36Z

Their use is reversed compared to DMA. The order for DMA makes more sense,
so let's use that

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
drivers/net/wireless/mediatek/mt76/usb.c | 30 ++++++++++++------------
1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c
index dcab5993763a..36e6cc3535fa 100644
--- a/drivers/net/wireless/mediatek/mt76/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/usb.c
@@ -497,8 +497,8 @@ mt76u_get_next_rx_entry(struct mt76_queue *q)

spin_lock_irqsave(&q->lock, flags);
if (q->queued > 0) {
- urb = q->entry[q->head].urb;
- q->head = (q->head + 1) % q->ndesc;
+ urb = q->entry[q->tail].urb;
+ q->tail = (q->tail + 1) % q->ndesc;
q->queued--;
}
spin_unlock_irqrestore(&q->lock, flags);
@@ -622,10 +622,10 @@ static void mt76u_complete_rx(struct urb *urb)
}

spin_lock_irqsave(&q->lock, flags);
- if (WARN_ONCE(q->entry[q->tail].urb != urb, "rx urb mismatch"))
+ if (WARN_ONCE(q->entry[q->head].urb != urb, "rx urb mismatch"))
goto out;

- q->tail = (q->tail + 1) % q->ndesc;
+ q->head = (q->head + 1) % q->ndesc;
q->queued++;
tasklet_schedule(&dev->usb.rx_tasklet);
out:
@@ -808,17 +808,17 @@ static void mt76u_tx_tasklet(unsigned long data)
q = sq->q;

while (q->queued > n_dequeued) {
- if (!q->entry[q->head].done)
+ if (!q->entry[q->tail].done)
break;

- if (q->entry[q->head].schedule) {
- q->entry[q->head].schedule = false;
+ if (q->entry[q->tail].schedule) {
+ q->entry[q->tail].schedule = false;
n_sw_dequeued++;
}

- entry = q->entry[q->head];
- q->entry[q->head].done = false;
- q->head = (q->head + 1) % q->ndesc;
+ entry = q->entry[q->tail];
+ q->entry[q->tail].done = false;
+ q->tail = (q->tail + 1) % q->ndesc;
n_dequeued++;

dev->drv->tx_complete_skb(dev, i, &entry);
@@ -913,7 +913,7 @@ mt76u_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
struct mt76_tx_info tx_info = {
.skb = skb,
};
- u16 idx = q->tail;
+ u16 idx = q->head;
int err;

if (q->queued == q->ndesc)
@@ -932,7 +932,7 @@ mt76u_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
q->entry[idx].urb, mt76u_complete_tx,
&q->entry[idx]);

- q->tail = (q->tail + 1) % q->ndesc;
+ q->head = (q->head + 1) % q->ndesc;
q->entry[idx].skb = tx_info.skb;
q->queued++;

@@ -944,7 +944,7 @@ static void mt76u_tx_kick(struct mt76_dev *dev, struct mt76_queue *q)
struct urb *urb;
int err;

- while (q->first != q->tail) {
+ while (q->first != q->head) {
urb = q->entry[q->first].urb;

trace_submit_urb(dev, urb);
@@ -1071,8 +1071,8 @@ void mt76u_stop_tx(struct mt76_dev *dev)
/* Assure we are in sync with killed tasklet. */
spin_lock_bh(&q->lock);
while (q->queued) {
- entry = q->entry[q->head];
- q->head = (q->head + 1) % q->ndesc;
+ entry = q->entry[q->tail];
+ q->tail = (q->tail + 1) % q->ndesc;
q->queued--;

dev->drv->tx_complete_skb(dev, i, &entry);
--
2.28.0