Re: [PATCH bpf-next 2/2] selftests/bpf: Add selftest for sleepable bpf_task_under_cgroup()

[Stanislav Fomichev <sdf@google.com>]

On 10/05, Yafang Shao wrote:
> The result as follows,
> 
>   $ tools/testing/selftests/bpf/test_progs --name=task_under_cgroup
>   #237     task_under_cgroup:OK
>   Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
> 
> And no error messages in dmesg.
> 
> Without the prev patch, there will be RCU warnings in dmesg.
> 
> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> ---
>  .../selftests/bpf/prog_tests/task_under_cgroup.c   |  8 +++++--
>  .../selftests/bpf/progs/test_task_under_cgroup.c   | 28 +++++++++++++++++++++-
>  2 files changed, 33 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c
> index 4224727..d1a5a5c 100644
> --- a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c
> +++ b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c
> @@ -30,8 +30,12 @@ void test_task_under_cgroup(void)
>  	if (!ASSERT_OK(ret, "test_task_under_cgroup__load"))
>  		goto cleanup;
>  
> -	ret = test_task_under_cgroup__attach(skel);
> -	if (!ASSERT_OK(ret, "test_task_under_cgroup__attach"))
> +	skel->links.lsm_run = bpf_program__attach_lsm(skel->progs.lsm_run);
> +	if (!ASSERT_OK_PTR(skel->links.lsm_run, "attach_lsm"))
> +		goto cleanup;
> +

So we rely on the second attach here to trigger the program above?
Maybe add a comment? Otherwise we might risk loosing this dependency
after some refactoring...

Other than that, both patches look good to me, feel free to use for both
if/when you resend:

Acked-by: Stanislav Fomichev <sdf@google.com>