Re: [PATCH dwarves v4 0/6] btf_encoder: emit type tags for bpf_arena pointers

Ihor Solodrai
2025-03-20T16:32:08Z

On 2/28/25 11:46 AM, Ihor Solodrai wrote:
> This patch series implements emitting appropriate BTF type tags for
> argument and return types of kfuncs marked with KF_ARENA_* flags.
>
> For additional context see the description of BPF patch
> "bpf: define KF_ARENA_* flags for bpf_arena kfuncs" [1].
>
> The feature depends on recent changes in libbpf [2].
>
> [1] https://lore.kernel.org/bpf/20250206003148.2308659-1-ihor.solodrai@linux.dev/
> [2] https://lore.kernel.org/bpf/20250130201239.1429648-1-ihor.solodrai@linux.dev/
>
> v3->v4:
> * Add a patch (#2) replacing compile-time libbpf version checks with
> runtime checks for symbol availablility
> * Add a patch (#3) bumping libbpf submodule commit to latest master
> * Modify "btf_encoder: emit type tags for bpf_arena pointers"
> (#2->#4) to not use compile time libbpf version checks
>
> v2->v3:
> * Nits in patch #1
>
> v1->v2:
> * Rewrite patch #1 refactoring btf_encoder__tag_kfuncs(): now the
> post-processing step is removed entirely, and kfuncs are tagged in
> btf_encoder__add_func().
> * Nits and renames in patch #2
> * Add patch #4 editing man pages
>
> v2: https://lore.kernel.org/dwarves/20250212201552.1431219-1-ihor.solodrai@linux.dev/
> v1: https://lore.kernel.org/dwarves/20250207021442.155703-1-ihor.solodrai@linux.dev/
>
> Ihor Solodrai (6):
> btf_encoder: refactor btf_encoder__tag_kfuncs()
> btf_encoder: use __weak declarations of version-dependent libbpf API
> pahole: sync with libbpf mainline
> btf_encoder: emit type tags for bpf_arena pointers
> pahole: introduce --btf_feature=attributes
> man-pages: describe attributes and remove reproducible_build

Hi Alan, Arnaldo.

This series hasn't received any comments in a while.
Do you plan to review/land this?

Thanks.

>
> btf_encoder.c | 328 ++++++++++++++++++++++-----------------------
> dwarves.h | 13 +-
> lib/bpf | 2 +-
> man-pages/pahole.1 | 7 +-
> pahole.c | 11 +-
> 5 files changed, 188 insertions(+), 173 deletions(-)
>