On Wed, Jul 5, 2023 at 9:00 AM Anton Protopopov <aspsk@xxxxxxxxxxxxx> wrote:
>
> Previous commits populated the ->elem_count per-cpu pointer for hash maps.
> Check that this pointer is non-NULL in an existing map.
>
> Signed-off-by: Anton Protopopov <aspsk@xxxxxxxxxxxxx>
> ---
> tools/testing/selftests/bpf/progs/map_ptr_kern.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> index db388f593d0a..d6e234a37ccb 100644
> --- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> +++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> @@ -33,6 +33,7 @@ struct bpf_map {
> __u32 value_size;
> __u32 max_entries;
> __u32 id;
> + __s64 *elem_count;
> } __attribute__((preserve_access_index));
>
> static inline int check_bpf_map_fields(struct bpf_map *map, __u32 key_size,
> @@ -111,6 +112,8 @@ static inline int check_hash(void)
>
> VERIFY(check_default_noinline(&hash->map, map));
>
> + VERIFY(map->elem_count != NULL);
> +
imo that's worse than no test.
Just use kfunc here and get the real count?
