Re: [PATCH bpf-next v4 6/9] selftests/bpf: Invoke attach_reuseport out of make_server

[Eduard Zingerman]

On Mon, 2024-06-24 at 12:33 +0800, Geliang Tang wrote:
> From: Geliang Tang <tanggeli...@kylinos.cn>
> 
> In order to facilitate subsequent commits to drop make_server(), this patch
> invokes attach_reuseport() out of make_server(), right after invoking
> make_server() if the passed "reuseport_prog" argument is not NULL.
> 
> Signed-off-by: Geliang Tang <tanggeli...@kylinos.cn>
> ---
>  .../selftests/bpf/prog_tests/sk_lookup.c      | 21 +++++++++----------
>  1 file changed, 10 insertions(+), 11 deletions(-)
> 
> diff --git a/tools/testing/selftests/bpf/prog_tests/sk_lookup.c 
> b/tools/testing/selftests/bpf/prog_tests/sk_lookup.c
> index de2466547efe..d87dfcf5db07 100644

Tbh, I don't like this refactoring for sk_lookup, it does not seem to
make the code clearer or shorter (e.g. 1414 LOC vs 1409).
If anything, it looks like reuseport_prog, callbacks setup and
start_server_str could be hidden insider make_server().

> --- a/tools/testing/selftests/bpf/prog_tests/sk_lookup.c
> +++ b/tools/testing/selftests/bpf/prog_tests/sk_lookup.c
> @@ -204,15 +204,6 @@ static int make_server(int sotype, const char *ip, int 
> port,
>               }
>       }
>  
> -     /* Late attach reuseport prog so we can have one init path */
> -     if (reuseport_prog) {
> -             err = attach_reuseport(fd, reuseport_prog);
> -             if (CHECK(err, "attach_reuseport", "failed\n")) {
> -                     log_err("failed to attach reuseport prog");
> -                     goto fail;
> -             }
> -     }
> -
>       return fd;
>  fail:
>       close(fd);
> @@ -610,7 +601,8 @@ static void run_lookup_prog(const struct test *t)
>               server_fds[i] = make_server(t->sotype, t->listen_at.ip,
>                                           t->listen_at.port,
>                                           t->reuseport_prog);
> -             if (server_fds[i] < 0)
> +             if (server_fds[i] < 0 ||
> +                 attach_reuseport(server_fds[i], t->reuseport_prog))
>                       goto close;
>  
>               err = update_lookup_map(t->sock_map, i, server_fds[i]);
> @@ -636,7 +628,8 @@ static void run_lookup_prog(const struct test *t)
>               reuse_conn_fd = make_server(t->sotype, t->listen_at.ip,
>                                           t->listen_at.port,
>                                           t->reuseport_prog);
> -             if (reuse_conn_fd < 0)
> +             if (reuse_conn_fd < 0 ||
> +                 attach_reuseport(reuse_conn_fd, t->reuseport_prog))
>                       goto close;
>  
>               /* Connect the extra socket to itself */
> @@ -878,6 +871,9 @@ static void drop_on_lookup(const struct test *t)
>       if (server_fd < 0)
>               goto detach;
>  
> +     if (attach_reuseport(server_fd, t->reuseport_prog))
> +             goto close_srv;
> +
>       client_fd = make_socket(t->sotype, t->connect_to.ip,
>                               t->connect_to.port, &dst);
>       if (client_fd < 0)
> @@ -992,6 +988,9 @@ static void drop_on_reuseport(const struct test *t)
>       if (server1 < 0)
>               goto detach;
>  
> +     if (attach_reuseport(server1, t->reuseport_prog))
> +             goto close_srv1;
> +
>       err = update_lookup_map(t->sock_map, SERVER_A, server1);
>       if (err)
>               goto close_srv1;