Wed, Dec 13, 2017 at 06:18:04PM CET, dsah...@gmail.com wrote: >On 12/13/17 10:07 AM, Jiri Pirko wrote: >> Wed, Dec 13, 2017 at 05:54:35PM CET, dsah...@gmail.com wrote: >>> On 12/13/17 8:10 AM, Jiri Pirko wrote: >>>> 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: >>>> >>>> $ tc qdisc >>>> qdisc ingress ffff: dev ens7 parent ffff:fff1 block 22 >>>> qdisc ingress ffff: dev ens8 parent ffff:fff1 block 22 >>>> >>>> To make is more visual, the situation looks like this: >>>> >>>> ens7 ingress qdisc ens7 ingress qdisc >>>> | | >>>> | | >>>> +----------> block 22 <----------+ >>>> >>>> Unlimited number of qdiscs may share the same block. >>>> >>>> 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 >>> >>> I still say this is very odd user semantic - making changes to device M >>> and the changes magically affect device N. Operating on the shared block >>> as a separate object makes it is much more direct and clear. >> >> I plan to do it as a follow-up patch. But this is how things are done >> now and have to continue to work. > >Why is that? You are introducing the notion of a shared block with this >patch set. What is the legacy "how things are done now" you are >referring to?
Well, the filter add/del should just work no matter if the block behind is shared or not. > >> Also changes done on dev block X for dev A has to appear in block X >> for dev B. Block X is share between A and B. >> > >Certainly - that's the definition of a shared block and you are >referring to display and datapath. For admin, it is more direct and >apparent in terms of what is happening to require changes (filter add >and deletes) to be done by specifying the shared block as the primary >object.
