2021-12-15 17:38:54

by Felix Fietkau

[permalink] [raw]
Subject: [PATCH 1/3] mt76: allow drivers to drop rx packets early

This can be used to free received events without allocating an extra skb

Signed-off-by: Felix Fietkau <[email protected]>
---
drivers/net/wireless/mediatek/mt76/dma.c | 19 ++++++++++++-------
drivers/net/wireless/mediatek/mt76/mt76.h | 2 ++
2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
index 5e1c1506a4c6..3a9af8931c35 100644
--- a/drivers/net/wireless/mediatek/mt76/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/dma.c
@@ -572,9 +572,7 @@ mt76_dma_rx_process(struct mt76_dev *dev, struct mt76_queue *q, int budget)
if (data_len < len + q->buf_offset) {
dev_kfree_skb(q->rx_head);
q->rx_head = NULL;
-
- skb_free_frag(data);
- continue;
+ goto free_frag;
}

if (q->rx_head) {
@@ -582,11 +580,14 @@ mt76_dma_rx_process(struct mt76_dev *dev, struct mt76_queue *q, int budget)
continue;
}

+ if (!more && dev->drv->rx_check &&
+ !(dev->drv->rx_check(dev, data, len)))
+ goto free_frag;
+
skb = build_skb(data, q->buf_size);
- if (!skb) {
- skb_free_frag(data);
- continue;
- }
+ if (!skb)
+ goto free_frag;
+
skb_reserve(skb, q->buf_offset);

if (q == &dev->q_rx[MT_RXQ_MCU]) {
@@ -603,6 +604,10 @@ mt76_dma_rx_process(struct mt76_dev *dev, struct mt76_queue *q, int budget)
}

dev->drv->rx_skb(dev, q - dev->q_rx, skb);
+ continue;
+
+free_frag:
+ skb_free_frag(data);
}

mt76_dma_rx_fill(dev, q);
diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index 239742112e16..8edbf42b4526 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -373,6 +373,8 @@ struct mt76_driver_ops {

bool (*tx_status_data)(struct mt76_dev *dev, u8 *update);

+ bool (*rx_check)(struct mt76_dev *dev, void *data, int len);
+
void (*rx_skb)(struct mt76_dev *dev, enum mt76_rxq_id q,
struct sk_buff *skb);

--
2.34.1