From: Jiri Pirko <j...@mellanox.com> Currently the filters added to qdiscs are independent. So for example if you have 2 netdevices and you create ingress qdisc on both and you want to add identical filter rules both, you need to add them twice. This patchset makes this easier and mainly saves resources allowing to share all filters within a qdisc - I call it a "filter block". Also this helps to save resources when we do offload to hw for example to expensive TCAM.
So back to the example. First, we create 2 qdiscs. Both will share block number 22. "22" is just an identification. If we don't pass any block number, a new one will be generated by kernel: $ tc qdisc add dev ens7 ingress block 22 ^^^^^^^^ $ tc qdisc add dev ens8 ingress block 22 ^^^^^^^^ Now if we list the qdiscs, we will see the block index in the output: qdisc fq_codel 0: dev ens7 root refcnt 2 limit 10240p flows 1024 quantum 1514 target 5.0ms interval 100.0ms memory_limit 32Mb ecn Sent 9014 bytes 99 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0 maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0 new_flows_len 0 old_flows_len 0 qdisc ingress ffff: dev ens7 parent ffff:fff1 block 22 ^^^^^^^^ Sent 4592 bytes 58 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0 qdisc fq_codel 0: dev ens8 root refcnt 2 limit 10240p flows 1024 quantum 1514 target 5.0ms interval 100.0ms memory_limit 32Mb ecn Sent 17022 bytes 307 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0 maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0 new_flows_len 0 old_flows_len 0 qdisc ingress ffff: dev ens8 parent ffff:fff1 block 22 ^^^^^^^^ Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0 Now we can add filter to any of qdiscs sharing the same block: $ tc filter add dev ens7 parent ffff: protocol ip pref 25 flower dst_ip 192.168.0.0/16 action drop We will see the same output if we list filters for ens7 and ens8, including stats: $ tc -s filter show dev ens7 root filter parent ffff: protocol ip pref 25 flower filter parent ffff: protocol ip pref 25 flower handle 0x1 eth_type ipv4 dst_ip 192.168.1.0/24 action order 1: gact action drop random type none pass val 0 index 3 ref 1 bind 1 installed 10201 sec used 10150 sec Action statistics: Sent 4200 bytes 50 pkt (dropped 50, overlimits 0 requeues 0) backlog 0b 0p requeues 0 $ tc -s filter show dev ens8 root filter dev ens7 parent ffff: protocol ip pref 25 flower filter dev ens7 parent ffff: protocol ip pref 25 flower handle 0x1 eth_type ipv4 dst_ip 192.168.1.0/24 action order 1: gact action drop random type none pass val 0 index 3 ref 1 bind 1 installed 10202 sec used 10152 sec Action statistics: Sent 4200 bytes 50 pkt (dropped 50, overlimits 0 requeues 0) backlog 0b 0p requeues 0 Issues: - tp->q is set by the device used to add the filter. That has to be resolved. Impacts the dump (as you can see above) Jiri Pirko (4): net: sched: introduce support for multiple filter chain pointers registration net: sched: intruduce qdisc_net helper net: sched: introduce shared filter blocks infrastructure net: sched: allow ingress and clsact qdiscs to share filter blocks include/net/pkt_cls.h | 22 +++- include/net/pkt_sched.h | 7 ++ include/net/sch_generic.h | 4 +- include/uapi/linux/pkt_sched.h | 12 +++ net/sched/cls_api.c | 240 +++++++++++++++++++++++++++++++++++++---- net/sched/sch_ingress.c | 107 ++++++++++++++++-- 6 files changed, 362 insertions(+), 30 deletions(-) -- 2.9.3