Subject: [PATCH net-next 0/4] TC: refactor act_mirred packets re-injection

From: Paolo Abeni <[email-masked]>
Date: Thu, 19 Jul 2018 15:02:25 +0200

This series is aimed at improving the act_mirred redirect performances.
Such action is used by OVS to represent TC S/W flows, and it's current largest
bottle-neck is the need for a skb_clone() for each packet.

The first 2 patches introduce some cleanup and safeguards to allow extending 
tca_result: we will use it to store RCU protected redirect information.
Then a new tca_action value is introduced: TC_ACT_MIRRED, similar to
TC_ACT_REDIRECT, but preserving the mirred semantic. The last patch exploits
the introduced infrastructure in the act_mirred action, to avoid a skb_clone,
when possible.

Overall this the above gives a ~10% performance improvement in forwarding tput,
when using the TC S/W datapath.

v1 -> v2:
 - preserve the rcu lock in act_bpf
 - add and use a new action value to reinject the packets, preserving the mirred
   semantic

Paolo Abeni (4):
  tc/act: user space can't use TC_ACT_REDIRECT directly
  tc/act: remove unneeded RCU lock in action callback
  net/tc: introduce TC_ACT_MIRRED.
  act_mirred: use ACT_MIRRED when possible

 include/net/act_api.h        |  2 +-
 include/net/sch_generic.h    | 21 +++++++++++++++++++++
 include/uapi/linux/pkt_cls.h |  2 ++
 net/core/dev.c               |  4 ++++
 net/sched/act_api.c          |  7 +++++++
 net/sched/act_csum.c         | 12 +++---------
 net/sched/act_ife.c          |  5 +----
 net/sched/act_mirred.c       | 35 +++++++++++++++++++++++------------
 net/sched/act_sample.c       |  4 +---
 net/sched/act_skbedit.c      | 10 +++-------
 net/sched/act_skbmod.c       | 21 +++++++++------------
 net/sched/act_tunnel_key.c   |  6 +-----
 net/sched/act_vlan.c         | 19 +++++++------------
 13 files changed, 83 insertions(+), 65 deletions(-)

-- 
2.17.1