Re: [PATCH v4 bpf-next 3/3] selftests/bpf: add selftest for get_netns_id helper

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Mon, Feb 24, 2020 at 11:20 PM Forrest Chen <forrest0579@gmail.com> wrote:
>
> > It would be nice if this selftests becomes part of test_progs.
>
> You mean the whole tests of tcpbpf or only the changes I made in this test?
> If you mean the whole tests of tcpbpf, I think we could fire another thread
> to do this?

Yeah, I meant entire tcpbpf test.

>
> Andrii Nakryiko <andrii.nakryiko@gmail.com> 于2020年2月25日周二 下午2:13写道：
>>
>> On Mon, Feb 24, 2020 at 8:47 PM Lingpeng Chen <forrest0579@gmail.com> wrote:
>> >
>> > adding selftest for new bpf helper function get_netns_id
>> >
>> > Signed-off-by: Lingpeng Chen <forrest0579@gmail.com>
>> > Acked-by: Song Liu <songliubraving@fb.com>
>> > ---
>>
>> It would be nice if this selftests becomes part of test_progs. That
>> way it would be exercised regularly, both by committers, as well as by
>> automated CI in libbpf's Github repo. Using global variables and BPF
>> skeleton would also clean up both BPF and user-space code.
>>
>> It seems like this test runs Python script for server, but doesn't
>> seem like that server is doing anything complicated, so writing that
>> in C shouldn't be a problem as well. Thoughts?
>>
>> >  .../selftests/bpf/progs/test_tcpbpf_kern.c    | 11 +++++
>> >  .../testing/selftests/bpf/test_tcpbpf_user.c  | 46 ++++++++++++++++++-
>> >  2 files changed, 56 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c b/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c
>> > index 1f1966e86e9f..d7d851ddd2cc 100644
>> > --- a/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c
>> > +++ b/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c
>> > @@ -28,6 +28,13 @@ struct {
>> >         __type(value, int);
>> >  } sockopt_results SEC(".maps");
>> >
>> > +struct {
>> > +       __uint(type, BPF_MAP_TYPE_ARRAY);
>> > +       __uint(max_entries, 1);
>> > +       __type(key, __u32);
>> > +       __type(value, __u64);
>> > +} netns_number SEC(".maps");
>> > +
>> >  static inline void update_event_map(int event)
>> >  {
>> >         __u32 key = 0;
>> > @@ -61,6 +68,7 @@ int bpf_testcb(struct bpf_sock_ops *skops)
>> >         int rv = -1;
>> >         int v = 0;
>> >         int op;
>> > +       __u64 netns_id;
>> >
>> >         op = (int) skops->op;
>> >
>> > @@ -144,6 +152,9 @@ int bpf_testcb(struct bpf_sock_ops *skops)
>> >                 __u32 key = 0;
>> >
>> >                 bpf_map_update_elem(&sockopt_results, &key, &v, BPF_ANY);
>> > +
>> > +               netns_id = bpf_get_netns_id(skops);
>> > +               bpf_map_update_elem(&netns_number, &key, &netns_id, BPF_ANY);
>> >                 break;
>> >         default:
>> >                 rv = -1;
>> > diff --git a/tools/testing/selftests/bpf/test_tcpbpf_user.c b/tools/testing/selftests/bpf/test_tcpbpf_user.c
>> > index 3ae127620463..fef2f4d77ecc 100644
>> > --- a/tools/testing/selftests/bpf/test_tcpbpf_user.c
>> > +++ b/tools/testing/selftests/bpf/test_tcpbpf_user.c
>> > @@ -76,6 +76,41 @@ int verify_sockopt_result(int sock_map_fd)
>> >         return ret;
>> >  }
>> >
>> > +int verify_netns(__u64 netns_id)
>> > +{
>> > +       char buf1[40];
>> > +       char buf2[40];
>> > +       int ret = 0;
>> > +       ssize_t len = 0;
>> > +
>> > +       len = readlink("/proc/self/ns/net", buf1, 39);
>> > +       sprintf(buf2, "net:[%llu]", netns_id);
>> > +
>> > +       if (len <= 0) {
>> > +               printf("FAILED: readlink /proc/self/ns/net");
>> > +               return ret;
>> > +       }
>> > +
>> > +       if (strncmp(buf1, buf2, len)) {
>> > +               printf("FAILED: netns don't match");
>> > +               ret = 1;
>> > +       }
>> > +       return ret;
>> > +}
>> > +
>> > +int verify_netns_result(int netns_map_fd)
>> > +{
>> > +       __u32 key = 0;
>> > +       __u64 res = 0;
>> > +       int ret = 0;
>> > +       int rv;
>> > +
>> > +       rv = bpf_map_lookup_elem(netns_map_fd, &key, &res);
>> > +       EXPECT_EQ(0, rv, "d");
>> > +
>> > +       return verify_netns(res);
>> > +}
>> > +
>> >  static int bpf_find_map(const char *test, struct bpf_object *obj,
>> >                         const char *name)
>> >  {
>> > @@ -92,7 +127,7 @@ static int bpf_find_map(const char *test, struct bpf_object *obj,
>> >  int main(int argc, char **argv)
>> >  {
>> >         const char *file = "test_tcpbpf_kern.o";
>> > -       int prog_fd, map_fd, sock_map_fd;
>> > +       int prog_fd, map_fd, sock_map_fd, netns_map_fd;
>> >         struct tcpbpf_globals g = {0};
>> >         const char *cg_path = "/foo";
>> >         int error = EXIT_FAILURE;
>> > @@ -137,6 +172,10 @@ int main(int argc, char **argv)
>> >         if (sock_map_fd < 0)
>> >                 goto err;
>> >
>> > +       netns_map_fd = bpf_find_map(__func__, obj, "netns_number");
>> > +       if (netns_map_fd < 0)
>> > +               goto err;
>> > +
>> >  retry_lookup:
>> >         rv = bpf_map_lookup_elem(map_fd, &key, &g);
>> >         if (rv != 0) {
>> > @@ -161,6 +200,11 @@ int main(int argc, char **argv)
>> >                 goto err;
>> >         }
>> >
>> > +       if (verify_netns_result(netns_map_fd)) {
>> > +               printf("FAILED: Wrong netns stats\n");
>> > +               goto err;
>> > +       }
>> > +
>> >         printf("PASSED!\n");
>> >         error = 0;
>> >  err:
>> > --
>> > 2.20.1
>> >
>
>
>
> --
> Beijing University of Posts and Telecommunications
> forrest0579@gmail.com
>
>