[PATCH net-next 0/2] net/sched: act_skbedit: lockless data path

[Davide Caratti <dcaratti@redhat.com>]

the data path of act_skbedit can be faster if we avoid using spinlocks:
 - patch 1 converts act_skbedit statistics to use per-cpu counters
 - patch 2 lets act_skbedit use RCU to read/update its configuration 

test procedure (using pktgen from https://github.com/netoptimizer):

 # ip link add name eth1 type dummy
 # ip link set dev eth1 up
 # tc qdisc add dev eth1 clsact
 # tc filter add dev eth1 egress matchall action skbedit priority c1a0:c1a0
 # for c in 1 2 4 ; do
 > ./pktgen_bench_xmit_mode_queue_xmit.sh -v -s 64 -t $c -n 5000000 -i eth1
 > done

test results (avg. pps/thread)

  $c | before patch |  after patch | improvement
 ----+--------------+--------------+------------
   1 | 3917464 ± 3% | 4000458 ± 3% |  irrelevant
   2 | 3455367 ± 4% | 3953076 ± 1% |        +14%
   4 | 2496594 ± 2% | 3801123 ± 3% |        +52%


Davide Caratti (2):
  net/sched: skbedit: use per-cpu counters
  net/sched: act_skbedit: don't use spinlock in the data path

 include/net/tc_act/tc_skbedit.h |  37 ++++++++---
 net/sched/act_skbedit.c         | 113 ++++++++++++++++++++------------
 2 files changed, 98 insertions(+), 52 deletions(-)

-- 
2.17.1