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

[Davide Caratti <dcaratti@redhat.com>]

the data path of 'police' action can be faster if we avoid using spinlocks:
 - patch 1 converts act_police to use per-cpu counters
 - patch 2 lets act_police use RCU to access its configuration data.

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 police \
 > rate 2gbit burst 100k conform-exceed pass/pass index 100
 # 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 |      3518448 |      3591240 |  irrelevant
   2 |      3070065 |      3383393 |         10%
   4 |      1540969 |      3238385 |        110%


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

 net/sched/act_police.c | 186 +++++++++++++++++++++++------------------
 1 file changed, 106 insertions(+), 80 deletions(-)

-- 
2.17.1