diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2017-11-30 15:35:33 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-12-02 21:14:59 -0500 |
| commit | 183dea5818315c0a172d21ecbcd2554894bf01e3 (patch) | |
| tree | ef7a0a843aea2434716659d40fb141630022baf4 | |
| parent | c5f66a85899705835f61d687a38f62d5a1ec4eb9 (diff) | |
| download | linux-183dea5818315c0a172d21ecbcd2554894bf01e3.tar.bz2 | |
openvswitch: do not propagate headroom updates to internal port
After commit 3a927bc7cf9d ("ovs: propagate per dp max headroom to
all vports") the need_headroom for the internal vport is updated
accordingly to the max needed headroom in its datapath.
That avoids the pskb_expand_head() costs when sending/forwarding
packets towards tunnel devices, at least for some scenarios.
We still require such copy when using the ovs-preferred configuration
for vxlan tunnels:
br_int
/ \
tap vxlan
(remote_ip:X)
br_phy
\
NIC
where the route towards the IP 'X' is via 'br_phy'.
When forwarding traffic from the tap towards the vxlan device, we
will call pskb_expand_head() in vxlan_build_skb() because
br-phy->needed_headroom is equal to tun->needed_headroom.
With this change we avoid updating the internal vport needed_headroom,
so that in the above scenario no head copy is needed, giving 5%
performance improvement in UDP throughput test.
As a trade-off, packets sent from the internal port towards a tunnel
device will now experience the head copy overhead. The rationale is
that the latter use-case is less relevant performance-wise.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/openvswitch/vport-internal_dev.c | 9 |
1 files changed, 1 insertions, 8 deletions
diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c index 04a3128adcf0..3e7747549f90 100644 --- a/net/openvswitch/vport-internal_dev.c +++ b/net/openvswitch/vport-internal_dev.c @@ -126,18 +126,12 @@ internal_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats) } } -static void internal_set_rx_headroom(struct net_device *dev, int new_hr) -{ - dev->needed_headroom = new_hr < 0 ? 0 : new_hr; -} - static const struct net_device_ops internal_dev_netdev_ops = { .ndo_open = internal_dev_open, .ndo_stop = internal_dev_stop, .ndo_start_xmit = internal_dev_xmit, .ndo_set_mac_address = eth_mac_addr, .ndo_get_stats64 = internal_get_stats, - .ndo_set_rx_headroom = internal_set_rx_headroom, }; static struct rtnl_link_ops internal_dev_link_ops __read_mostly = { @@ -154,7 +148,7 @@ static void do_setup(struct net_device *netdev) netdev->priv_flags &= ~IFF_TX_SKB_SHARING; netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH | - IFF_PHONY_HEADROOM | IFF_NO_QUEUE; + IFF_NO_QUEUE; netdev->needs_free_netdev = true; netdev->priv_destructor = internal_dev_destructor; netdev->ethtool_ops = &internal_dev_ethtool_ops; @@ -195,7 +189,6 @@ static struct vport *internal_dev_create(const struct vport_parms *parms) err = -ENOMEM; goto error_free_netdev; } - vport->dev->needed_headroom = vport->dp->max_headroom; dev_net_set(vport->dev, ovs_dp_get_net(vport->dp)); internal_dev = internal_dev_priv(vport->dev); |