diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2016-02-26 10:45:41 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-03-01 15:54:31 -0500 |
| commit | 163e529200af7b7521fbde5dbcc653cf3ce597df (patch) | |
| tree | 2530b68faffa4a6cb301fb71c64cab0ee69f3747 /drivers/net/veth.c | |
| parent | eaea34b23c46bf17b4a5638be69ab3561854f34b (diff) | |
veth: implement ndo_set_rx_headroom
The rx headroom for veth dev is the peer device needed_headroom.
Avoid ping-pong updates setting the private flag IFF_PHONY_HEADROOM.
This avoids skb head reallocation when forwarding from a veth dev
towards a device adding some kind of encapsulation.
When transmitting frames below the MTU size towards a vxlan device,
this gives about 10% performance speed-up when OVS is used to connect
the veth and the vxlan device and a little more when using a
plain Linux bridge.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/veth.c')
| -rw-r--r-- | drivers/net/veth.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/net/veth.c b/drivers/net/veth.c index ba21d072be31..4f30a6ae50d0 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -35,6 +35,7 @@ struct pcpu_vstats { struct veth_priv { struct net_device __rcu *peer; atomic64_t dropped; + unsigned requested_headroom; }; /* @@ -271,6 +272,29 @@ static int veth_get_iflink(const struct net_device *dev) return iflink; } +static void veth_set_rx_headroom(struct net_device *dev, int new_hr) +{ + struct veth_priv *peer_priv, *priv = netdev_priv(dev); + struct net_device *peer; + + if (new_hr < 0) + new_hr = 0; + + rcu_read_lock(); + peer = rcu_dereference(priv->peer); + if (unlikely(!peer)) + goto out; + + peer_priv = netdev_priv(peer); + priv->requested_headroom = new_hr; + new_hr = max(priv->requested_headroom, peer_priv->requested_headroom); + dev->needed_headroom = new_hr; + peer->needed_headroom = new_hr; + +out: + rcu_read_unlock(); +} + static const struct net_device_ops veth_netdev_ops = { .ndo_init = veth_dev_init, .ndo_open = veth_open, @@ -285,6 +309,7 @@ static const struct net_device_ops veth_netdev_ops = { #endif .ndo_get_iflink = veth_get_iflink, .ndo_features_check = passthru_features_check, + .ndo_set_rx_headroom = veth_set_rx_headroom, }; #define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \ @@ -301,6 +326,7 @@ static void veth_setup(struct net_device *dev) dev->priv_flags &= ~IFF_TX_SKB_SHARING; dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; dev->priv_flags |= IFF_NO_QUEUE; + dev->priv_flags |= IFF_PHONY_HEADROOM; dev->netdev_ops = &veth_netdev_ops; dev->ethtool_ops = &veth_ethtool_ops; |