selftests/bpf: Implement sample udp/udp6 bpf_iter programs
On my VM, I got identical results between /proc/net/udp[6] and
the udp{4,6} bpf iterator.
For udp6:
$ cat /sys/fs/bpf/p1
sl local_address remote_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode ref pointer drops
1405:
000080FE00000000FF7CC4D0D9EFE4FE:0222
00000000000000000000000000000000:0000 07
00000000:
00000000 00:
00000000 00000000 193 0 19183 2
0000000029eab111 0
$ cat /proc/net/udp6
sl local_address remote_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode ref pointer drops
1405:
000080FE00000000FF7CC4D0D9EFE4FE:0222
00000000000000000000000000000000:0000 07
00000000:
00000000 00:
00000000 00000000 193 0 19183 2
0000000029eab111 0
For udp4:
$ cat /sys/fs/bpf/p4
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode ref pointer drops
2007:
00000000:1F90
00000000:0000 07
00000000:
00000000 00:
00000000 00000000 0 0 72540 2
000000004ede477a 0
$ cat /proc/net/udp
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode ref pointer drops
2007:
00000000:1F90
00000000:0000 07
00000000:
00000000 00:
00000000 00000000 0 0 72540 2
000000004ede477a 0
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230822.3989299-1-yhs@fb.com