Thu, Nov 16, 2017 at 12:12:47AM CET, xiyou.wangc...@gmail.com wrote: >On Sun, Nov 12, 2017 at 7:55 AM, Jiri Pirko <j...@resnulli.us> wrote: >> 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: > >Should not block 0 by used by default if not specified by user? >Why a new one?
That would mean you would share block 0 among all newly created qdiscs. That is not right. By default, there should be no sharing. > > >> >> $ 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: >> >> $ tc qdisc >> qdisc ingress ffff: dev ens7 parent ffff:fff1 block 22 >> qdisc ingress ffff: dev ens8 parent ffff:fff1 block 22 >> >> Now we can add filter to any of qdiscs sharing the same block: >> >> $ tc filter add dev ens7 ingress protocol ip pref 25 flower dst_ip >> 192.168.0.0/16 action drop >> > >So you don't need to specify block 22 for this filter? >Because there is only one block??? eth7 was ingress qdisc was assigned block 22 during the creation. There is always 1 block assigned to one qdisc. However there might be multiple qdiscs sharing one block. I will try to make this more clear in the cover letter. > > >> >> We will see the same output if we list filters for ens7 and ens8, including >> stats: >> >> $ tc -s filter show dev ens7 ingress >> filter protocol ip pref 25 flower chain 0 >> filter protocol ip pref 25 flower chain 0 handle 0x1 >> eth_type ipv4 >> dst_ip 192.168.0.0/16 >> not_in_hw >> action order 1: gact action drop >> random type none pass val 0 >> index 1 ref 1 bind 1 installed 39 sec used 2 sec >> Action statistics: >> Sent 3108 bytes 37 pkt (dropped 37, overlimits 0 requeues 0) >> backlog 0b 0p requeues 0 > > >Don't see which block it belongs to here.
