r8152: support stopping/waking tx queue
The maximum packet number which a tx aggregation buffer could contain
is the tx_qlen.
tx_qlen = buffer size / (packet size + descriptor size).
If the tx buffer is empty and the queued packets are more than the
maximum value which is defined above, stop the tx queue. Wake the
tx queue if tx queue is stopped and the queued packets are less than
tx_qlen.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index 8a786b6..f92e0cf 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -365,6 +365,7 @@
struct mii_if_info mii;
int intr_interval;
u32 msg_enable;
+ u32 tx_qlen;
u16 ocp_base;
u8 *intr_buff;
u8 version;
@@ -1173,6 +1174,14 @@
remain = rx_buf_sz - (int)(tx_agg_align(tx_data) - agg->head);
}
+ netif_tx_lock(tp->netdev);
+
+ if (netif_queue_stopped(tp->netdev) &&
+ skb_queue_len(&tp->tx_queue) < tp->tx_qlen)
+ netif_wake_queue(tp->netdev);
+
+ netif_tx_unlock(tp->netdev);
+
usb_fill_bulk_urb(agg->urb, tp->udev, usb_sndbulkpipe(tp->udev, 2),
agg->head, (int)(tx_data - (u8 *)agg->head),
(usb_complete_t)write_bulk_callback, agg);
@@ -1393,6 +1402,10 @@
skb_queue_tail(&tp->tx_queue, skb);
+ if (list_empty(&tp->tx_free) &&
+ skb_queue_len(&tp->tx_queue) > tp->tx_qlen)
+ netif_stop_queue(netdev);
+
if (!list_empty(&tp->tx_free))
tasklet_schedule(&tp->tl);
@@ -1423,6 +1436,14 @@
}
}
+static void set_tx_qlen(struct r8152 *tp)
+{
+ struct net_device *netdev = tp->netdev;
+
+ tp->tx_qlen = rx_buf_sz / (netdev->mtu + VLAN_ETH_HLEN + VLAN_HLEN +
+ sizeof(struct tx_desc));
+}
+
static inline u8 rtl8152_get_speed(struct r8152 *tp)
{
return ocp_read_byte(tp, MCU_TYPE_PLA, PLA_PHYSTATUS);
@@ -1434,6 +1455,7 @@
int i, ret;
u8 speed;
+ set_tx_qlen(tp);
speed = rtl8152_get_speed(tp);
if (speed & _10bps) {
ocp_data = ocp_read_word(tp, MCU_TYPE_PLA, PLA_EEEP_CR);