Introduce BPF_F_TEST_STATE_FREQ flag to stress test parentage chain and state pruning. Change-Id: I89a8f21d4436a181045b56779a2213bd8b5d071b Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>