Re: [RFC PATCH v3 3/3] btf: Reuse libbpf code for BTF type sorting verification and binary search

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

On Mon, Oct 27, 2025 at 6:54 AM Donglin Peng <dolinux.peng@gmail.com> wrote:
>
> The previous commit implemented BTF sorting verification and binary
> search algorithm in libbpf. This patch enables this functionality in
> the kernel.
>
> Cc: Eduard Zingerman <eddyz87@gmail.com>
> Cc: Alexei Starovoitov <ast@kernel.org>
> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
> Cc: Alan Maguire <alan.maguire@oracle.com>
> Cc: Song Liu <song@kernel.org>
> Signed-off-by: pengdonglin <pengdonglin@xiaomi.com>
> Signed-off-by: Donglin Peng <dolinux.peng@gmail.com>
> ---
> v2->v3:
> - Include btf_sort.c directly in btf.c to reduce function call overhead
> ---
>  kernel/bpf/btf.c | 34 ++++++++++++++++++----------------
>  1 file changed, 18 insertions(+), 16 deletions(-)
>
> diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
> index 0de8fc8a0e0b..df258815a6ca 100644
> --- a/kernel/bpf/btf.c
> +++ b/kernel/bpf/btf.c
> @@ -33,6 +33,7 @@
>  #include <net/sock.h>
>  #include <net/xdp.h>
>  #include "../tools/lib/bpf/relo_core.h"
> +#include "../tools/lib/bpf/btf_sort.h"

I don't believe in code reuse for the sake of code reuse. This code
sharing just makes everything more entangled and complicated.
Reimplementing binary search is totally fine, IMO.

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