Fri, Aug 25, 2017 at 01:51:30AM CEST, [email protected] wrote: >It is ugly to hide a u32-filter-specific pointer inside Qdisc, >this breaks the TC layers: > >1. Qdisc is a generic representation, should not have any specific > data of any type > >2. Qdisc layer is above filter layer, should only save filters in > the list of struct tcf_proto. > >This pointer is used as the head of the chain of u32 hash tables, >that is struct tc_u_hnode, because u32 filter is very special, >it allows to create multiple hash tables within one qdisc and >across multiple u32 filters. > >Instead of using this ugly pointer, we can just save it in a global >hash table key'ed by (dev ifindex, qdisc handle), therefore we can >still treat it as a per qdisc basis data structure conceptually. > >Of course, because of network namespaces, this key is not unique >at all, but it is fine as we already have a pointer to Qdisc in >struct tc_u_common, we can just compare the pointers when collision. > >And this only affects slow paths, has no impact to fast path, >thanks to the pointer ->tp_c. > >Cc: Jamal Hadi Salim <[email protected]> >Cc: Jiri Pirko <[email protected]> >Signed-off-by: Cong Wang <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
