On Mon, Aug 21, 2023 at 10:06 PM Dave Marchevsky <davemarchevsky@xxxxxx> wrote:
>
> Commit 6018e1f407cc ("bpf: implement numbers iterator") added the
> BTF_TYPE_EMIT line that this patch is modifying. The struct btf_iter_num
> doesn't exist, so only a forward declaration is emitted in BTF:
>
> FWD 'btf_iter_num' fwd_kind=struct
>
> That commit was probably hoping to ensure that struct bpf_iter_num is
> emitted in vmlinux BTF. A previous version of this patch changed the
> line to emit the correct type, but Yonghong confirmed that it would
> definitely be emitted regardless in [0], so this patch simply removes
> the line.
>
> This isn't marked "Fixes" because the extraneous btf_iter_num FWD wasn't
> causing any issues that I noticed, aside from mild confusion when I
> looked through the code.
>
> [0]: https://lore.kernel.org/bpf/25d08207-43e6-36a8-5e0f-47a913d4cda5@xxxxxxxxx/
>
> Signed-off-by: Dave Marchevsky <davemarchevsky@xxxxxx>
> Acked-by: Yonghong Song <yonghong.song@xxxxxxxxx>
> ---
> kernel/bpf/bpf_iter.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
> index 96856f130cbf..833faa04461b 100644
> --- a/kernel/bpf/bpf_iter.c
> +++ b/kernel/bpf/bpf_iter.c
> @@ -793,8 +793,6 @@ __bpf_kfunc int bpf_iter_num_new(struct bpf_iter_num *it, int start, int end)
> BUILD_BUG_ON(sizeof(struct bpf_iter_num_kern) != sizeof(struct bpf_iter_num));
> BUILD_BUG_ON(__alignof__(struct bpf_iter_num_kern) != __alignof__(struct bpf_iter_num));
>
> - BTF_TYPE_EMIT(struct btf_iter_num);
> -
heh, hard to notice this typo... I think I needed it for the version
of patch set before the switch to kfunc, so yeah, we don't need it
anymore, thanks!
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
> /* start == end is legit, it's an empty range and we'll just get NULL
> * on first (and any subsequent) bpf_iter_num_next() call
> */
> --
> 2.34.1
>
