1 This file describes how to run the tcp_*_kern.o tcp_bpf (or socket_ops)
2 programs. These programs attach to a cgroupv2. The following commands create
3 a cgroupv2 and attach a bash shell to the group.
6 mount -t cgroup2 none /tmp/cgroupv2
7 mkdir -p /tmp/cgroupv2/foo
9 echo $$ >> /tmp/cgroupv2/foo/cgroup.procs
11 Anything that runs under this shell belongs to the foo cgroupv2. To load
12 (attach) one of the tcp_*_kern.o programs:
14 bpftool prog load tcp_basertt_kern.o /sys/fs/bpf/tcp_prog
15 bpftool cgroup attach /tmp/cgroupv2/foo sock_ops pinned /sys/fs/bpf/tcp_prog
18 "bpftool prog tracelog" will continue to run printing the BPF log buffer.
19 The tcp_*_kern.o programs use special print functions to print logging
20 information (if enabled by the ifdef).
22 If using netperf/netserver to create traffic, you need to run them under the
23 cgroupv2 to which the BPF programs are attached (i.e. under bash shell
24 attached to the cgroupv2).
26 To remove (unattach) a socket_ops BPF program from a cgroupv2:
28 bpftool cgroup detach /tmp/cgroupv2/foo sock_ops pinned /sys/fs/bpf/tcp_prog