On 06/22/2016 11:17 PM, Martin KaFai Lau wrote:
test_cgrp2_array_pin.c: A userland program that creates a bpf_map (BPF_MAP_TYPE_GROUP_ARRAY), pouplates/updates it with a cgroup2's backed fd and pins it to a bpf-fs's file. The pinned file can be loaded by tc and then used by the bpf prog later. This program can also update an existing pinned array and it could be useful for debugging/testing purpose.test_cgrp2_tc_kern.c: A bpf prog which should be loaded by tc. It is to demonstrate the usage of bpf_skb_in_cgroup. test_cgrp2_tc.sh: A script that glues the test_cgrp2_array_pin.c and test_cgrp2_tc_kern.c together. The idea is like: 1. Use test_cgrp2_array_pin.c to populate a BPF_MAP_TYPE_CGROUP_ARRAY with a cgroup fd 2. Load the test_cgrp2_tc_kern.o by tc 3. Do a 'ping -6 ff02::1%ve' to ensure the packet has been dropped because of a match on the cgroup Most of the lines in test_cgrp2_tc.sh is the boilerplate to setup the cgroup/bpf-fs/net-devices/netns...etc. It is not bulletproof on errors but should work well enough and give enough debug info if things did not go well. Signed-off-by: Martin KaFai Lau <ka...@fb.com> Cc: Alexei Starovoitov <a...@fb.com> Cc: Daniel Borkmann <dan...@iogearbox.net> Cc: Tejun Heo <t...@kernel.org> Acked-by: Alexei Starovoitov <a...@kernel.org>
Btw, when no bpf fs is mounted, tc will already auto-mount it. I noticed in your script, you do mount the fs manually. I guess it's okay to leave it like this, but I hope users won't wrongly copy it assuming they /have/ to mount it themselves.
