On 2018-09-09 11:48 a.m., Al Viro wrote:


BTW, shouldn't we issue u32_clear_hw_hnode() every time
we destroy an hnode?  It's done on u32_delete(), it's
done (for root ht) on u32_destroy(), but it's not done
for any other hnodes when you remove the entire (not shared)
filter.  Looks fishy...


What you are saying makes sense, but that doesnt seem
like a new thing.
All hardware offload examples I have seen use root tables
only[1]. So I am not sure if they use any other tables
although the intel hardware at least seems very capable.
Look at ixgbe_main.c for example. Theres an explicit assumption
that root is always 0x800 but oresence of

+Cc some of the NIC vendor folks..



cheers,
jamal

[1]
Here's a script posted by someone at Intel(Sridhar?) a while back
that adds 2 filters, one with skip-sw and the other with skip-hw
flag.

---
   # add ingress qdisc
   tc qdisc add dev p4p1 ingress

   # enable hw tc offload.
   ethtool -K p4p1 hw-tc-offload on

   # add u32 filter with skip-sw flag.
   tc filter add dev p4p1 parent ffff: protocol ip prio 99 \
      handle 800:0:1 u32 ht 800: flowid 800:1 \
      skip-sw \
      match ip src 192.168.1.0/24 \
      action drop

   # add u32 filter with skip-hw flag.
   tc filter add dev p4p1 parent ffff: protocol ip prio 99 \
      handle 800:0:2 u32 ht 800: flowid 800:2 \
      skip-hw \
      match ip src 192.168.2.0/24 \
      action drop
----

Reply via email to