Commit d2692eee authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: typhoon: implement ndo_features_check method 



Instead of disabling TSO at compile time if MAX_SKB_FRAGS > 32,
implement ndo_features_check() method for this driver for
a more dynamic handling.

If skb has more than 32 frags and is a GSO packet, force
software segmentation.

Most locally generated packets will use a small number
of fragments anyway.

For forwarding workloads, we can limit gro_max_size at ingress,
we might also implement gro_max_segs if needed.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5f215513

drivers/net/ethernet/3com/typhoon.c

+16 −5
Original line number Diff line number Diff line
@@ -138,11 +138,6 @@ MODULE_PARM_DESC(use_mmio, "Use MMIO (1) or PIO(0) to access the NIC. " 
module_param(rx_copybreak, int, 0);

module_param(use_mmio, int, 0);



#if defined(NETIF_F_TSO) && MAX_SKB_FRAGS > 32

#warning Typhoon only supports 32 entries in its SG list for TSO, disabling TSO

#undef NETIF_F_TSO

#endif



#if TXLO_ENTRIES <= (2 * MAX_SKB_FRAGS)

#error TX ring too small!

#endif
@@ -2261,9 +2256,25 @@ typhoon_test_mmio(struct pci_dev *pdev) 
	return mode;

}



#if MAX_SKB_FRAGS > 32

static netdev_features_t typhoon_features_check(struct sk_buff *skb,

						struct net_device *dev,

						netdev_features_t features)

{

	if (skb_shinfo(skb)->nr_frags > 32 && skb_is_gso(skb))

		features &= ~NETIF_F_GSO_MASK;



	features = vlan_features_check(skb, features);

	return vxlan_features_check(skb, features);

}

#endif



static const struct net_device_ops typhoon_netdev_ops = {

	.ndo_open		= typhoon_open,

	.ndo_stop		= typhoon_close,

#if MAX_SKB_FRAGS > 32

	.ndo_features_check	= typhoon_features_check,

#endif

	.ndo_start_xmit		= typhoon_start_tx,

	.ndo_set_rx_mode	= typhoon_set_rx_mode,

	.ndo_tx_timeout		= typhoon_tx_timeout,