Commit 9020845f authored by Heiner Kallweit's avatar Heiner Kallweit Committed by David S. Miller
Browse files

r8169: improve rtl8169_start_xmit 



Only call rtl8169_xmit_frags() if the skb is actually fragmented.
This avoid a small overhead for non-fragmented skb's, and it allows
to simplify rtl8169_xmit_frags() a little.

Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8e3a5735

drivers/net/ethernet/realtek/r8169_main.c

+10 −13
Original line number Diff line number Diff line
@@ -4087,12 +4087,10 @@ static int rtl8169_xmit_frags(struct rtl8169_private *tp, struct sk_buff *skb, 
		tp->tx_skb[entry].len = len;

	}



	if (cur_frag) {

	tp->tx_skb[entry].skb = skb;

	txd->opts1 |= cpu_to_le32(LastFrag);

	}



	return cur_frag;

	return 0;



err_out:

	rtl8169_tx_clear_range(tp, tp->cur_tx + 1, cur_frag);
@@ -4217,6 +4215,7 @@ static void rtl8169_doorbell(struct rtl8169_private *tp) 
static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,

				      struct net_device *dev)

{

	unsigned int frags = skb_shinfo(skb)->nr_frags;

	struct rtl8169_private *tp = netdev_priv(dev);

	unsigned int entry = tp->cur_tx % NUM_TX_DESC;

	struct TxDesc *txd = tp->TxDescArray + entry;
@@ -4225,9 +4224,8 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, 
	u32 opts[2], len;

	bool stop_queue;

	bool door_bell;

	int frags;



	if (unlikely(!rtl_tx_slots_avail(tp, skb_shinfo(skb)->nr_frags))) {

	if (unlikely(!rtl_tx_slots_avail(tp, frags))) {

		netif_err(tp, drv, dev, "BUG! Tx Ring full when queue awake!\n");

		goto err_stop_0;

	}
@@ -4256,14 +4254,13 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, 
	tp->tx_skb[entry].len = len;

	txd->addr = cpu_to_le64(mapping);



	frags = rtl8169_xmit_frags(tp, skb, opts);

	if (frags < 0)

		goto err_dma_1;

	else if (frags)

		opts[0] |= FirstFrag;

	else {

	if (!frags) {

		opts[0] |= FirstFrag | LastFrag;

		tp->tx_skb[entry].skb = skb;

	} else {

		if (rtl8169_xmit_frags(tp, skb, opts))

			goto err_dma_1;

		opts[0] |= FirstFrag;

	}



	txd->opts2 = cpu_to_le32(opts[1]);

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