[ovs-git] [openvswitch/ovs] 73858f: netdev-linux: Prepend the std packet in the TSO pa...

[Flavio Leitner]

  Branch: refs/heads/master
  Home:   https://github.com/openvswitch/ovs
  Commit: 73858f9dbe83daf8cc8d4b604acc23eb62cc3f52
      https://github.com/openvswitch/ovs/commit/73858f9dbe83daf8cc8d4b604acc23eb62cc3f52
  Author: Flavio Leitner <fbl at sysclose.org>
  Date:   2020-02-06 (Thu, 06 Feb 2020)

  Changed paths:
    M lib/dp-packet.c
    M lib/dp-packet.h
    M lib/netdev-linux-private.h
    M lib/netdev-linux.c

  Log Message:
  -----------
  netdev-linux: Prepend the std packet in the TSO packet

Usually TSO packets are close to 50k, 60k bytes long, so to
to copy less bytes when receiving a packet from the kernel
change the approach. Instead of extending the MTU sized
packet received and append with remaining TSO data from
the TSO buffer, allocate a TSO packet with enough headroom
to prepend the std packet data.

Fixes: 29cf9c1b3b9c ("userspace: Add TCP Segmentation Offload support")
Suggested-by: Ben Pfaff <blp at ovn.org>
Signed-off-by: Flavio Leitner <fbl at sysclose.org>
Signed-off-by: Ben Pfaff <blp at ovn.org>