Re: [PATCH v3 bpf 2/2] selftests/bpf: extend map-in-map selftest to detect memory leaks

[Song Liu <song@xxxxxxxxxx>]

On Mon, Jul 27, 2020 at 5:32 PM Andrii Nakryiko <andriin@xxxxxx> wrote:
>
> Add test validating that all inner maps are released properly after skeleton
> is destroyed. To ensure determinism, trigger kernel-side synchronize_rcu()
> before checking map existence by their IDs.
>
> Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>

Acked-by: Song Liu <songliubraving@xxxxxx>

With one last nitpick...

> ---
>  .../selftests/bpf/prog_tests/btf_map_in_map.c | 124 ++++++++++++++++--
>  1 file changed, 110 insertions(+), 14 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c b/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c
> index f7ee8fa377ad..2af1996df6f3 100644
> --- a/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c
> +++ b/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c
> @@ -5,10 +5,60 @@
>
>  #include "test_btf_map_in_map.skel.h"
>
> +static int duration;
> +
> +__u32 bpf_map_id(struct bpf_map *map)

nit: We can make this function static.