[mirror_ubuntu-bionic-kernel.git] / samples / bpf / tcp_bpf.readme

This file describes how to run the tcp_*_kern.o tcp_bpf (or socket_ops)
programs. These programs attach to a cgroupv2. The following commands create
a cgroupv2 and attach a bash shell to the group.

  mkdir -p /tmp/cgroupv2
  mount -t cgroup2 none /tmp/cgroupv2
  mkdir -p /tmp/cgroupv2/foo
  bash
  echo $$ >> /tmp/cgroupv2/foo/cgroup.procs

Anything that runs under this shell belongs to the foo cgroupv2 To load
(attach) one of the tcp_*_kern.o programs:

  ./load_sock_ops -l /tmp/cgroupv2/foo tcp_basertt_kern.o

If the "-l" flag is used, the load_sock_ops program will continue to run
printing the BPF log buffer. The tcp_*_kern.o programs use special print
functions to print logging information (if enabled by the ifdef).

If using netperf/netserver to create traffic, you need to run them under the
cgroupv2 to which the BPF programs are attached (i.e. under bash shell
attached to the cgroupv2).

To remove (unattach) a socket_ops BPF program from a cgroupv2:

  ./load_sock_ops -r /tmp/cgroupv2/foo
Commit	Line	Data
bfdf7569 LB	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.
	4
	5	mkdir -p /tmp/cgroupv2
	6	mount -t cgroup2 none /tmp/cgroupv2
	7	mkdir -p /tmp/cgroupv2/foo
	8	bash
	9	echo $$ >> /tmp/cgroupv2/foo/cgroup.procs
	10
	11	Anything that runs under this shell belongs to the foo cgroupv2 To load
	12	(attach) one of the tcp_*_kern.o programs:
	13
	14	./load_sock_ops -l /tmp/cgroupv2/foo tcp_basertt_kern.o
	15
	16	If the "-l" flag is used, the load_sock_ops program will continue to run
	17	printing the BPF log buffer. The tcp_*_kern.o programs use special print
	18	functions to print logging information (if enabled by the ifdef).
	19
	20	If using netperf/netserver to create traffic, you need to run them under the
	21	cgroupv2 to which the BPF programs are attached (i.e. under bash shell
	22	attached to the cgroupv2).
	23
	24	To remove (unattach) a socket_ops BPF program from a cgroupv2:
	25
	26	./load_sock_ops -r /tmp/cgroupv2/foo