On 16-11-10 11:35 AM, John Fastabend wrote: > On 16-11-10 03:23 AM, Jiri Pirko wrote: >> From: Yotam Gigi <yot...@mellanox.com> >> >> This action allow the user to sample traffic matched by tc classifier. >> The sampling consists of choosing packets randomly, truncating them, >> adding some informative metadata regarding the interface and the original >> packet size and mark them with specific mark, to allow further tc rules to >> match and process. The marked sample packets are then injected into the >> device ingress qdisc using netif_receive_skb. >> >> The packets metadata is packed using the ife encapsulation protocol, and >> the outer packet's ethernet dest, source and eth_type, along with the >> rate, mark and the optional truncation size can be configured from >> userspace. >> >> Example: >> To sample ingress traffic from interface eth1, and redirect the sampled >> the sampled packets to interface dummy0, one may use the commands: >> >> tc qdisc add dev eth1 handle ffff: ingress >> >> tc filter add dev eth1 parent ffff: \ >> matchall action sample rate 12 mark 17 >> >> tc filter add parent ffff: dev eth1 protocol all \ >> u32 match mark 17 0xff \ >> action mirred egress redirect dev dummy0 >> >> Where the first command adds an ingress qdisc and the second starts >> sampling every 12'th packet on dev eth1 and marks the sampled packets with >> 17. The third command catches the sampled packets, which are marked with >> 17, and redirects them to dev dummy0. > > The sampling algorithm was not randomized based on the above commit > log? It really needs to be for all the reasons Roopa mentioned earlier. > Did I miss some email on why it didn't get implemented? > > Also there was an indication the already is actually implemented > correctly so don't we need the hw/sw to behave the same. The whole > argument about sw/hw parity, etc.
sorry bit of a typo there corrected 2nd paragraph here... Also there was an indication the hardware is already implemented \ correctly so don't we need the hw/sw to behave the same. The argument about sw/hw parity, etc. > >> >> Signed-off-by: Yotam Gigi <yot...@mellanox.com> >> Signed-off-by: Jiri Pirko <j...@mellanox.com> >> --- >
