Re: [PATCH bpf-next 3/3] selftests/bpf: add tests for bpf_dynptr_copy

[Eduard Zingerman <eddyz87@gmail.com>]

On Thu, 2025-02-20 at 16:52 -0800, Andrii Nakryiko wrote:
> On Tue, Feb 18, 2025 at 11:01 AM Mykyta Yatsenko
> <mykyta.yatsenko5@gmail.com> wrote:
> > 
> > From: Mykyta Yatsenko <yatsenko@meta.com>
> > 
> > Add XDP setup type for dynptr tests, enabling testing for
> > non-contiguous buffer.
> > Add 2 tests:
> >  - test_dynptr_copy - verify correctness for the fast (contiguous
> >  buffer) code path.
> >  - test_dynptr_copy_xdp - verifies code paths that handle
> >  non-contiguous buffer.
> > 
> > Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
> > ---
> >  tools/testing/selftests/bpf/bpf_kfuncs.h      |  8 ++
> >  .../testing/selftests/bpf/prog_tests/dynptr.c | 25 ++++++
> >  .../selftests/bpf/progs/dynptr_success.c      | 77 +++++++++++++++++++
> >  3 files changed, 110 insertions(+)
> > 
> > diff --git a/tools/testing/selftests/bpf/bpf_kfuncs.h b/tools/testing/selftests/bpf/bpf_kfuncs.h
> > index 8215c9b3115e..e9c193036c82 100644
> > --- a/tools/testing/selftests/bpf/bpf_kfuncs.h
> > +++ b/tools/testing/selftests/bpf/bpf_kfuncs.h
> > @@ -43,6 +43,14 @@ extern bool bpf_dynptr_is_rdonly(const struct bpf_dynptr *ptr) __ksym __weak;
> >  extern __u32 bpf_dynptr_size(const struct bpf_dynptr *ptr) __ksym __weak;
> >  extern int bpf_dynptr_clone(const struct bpf_dynptr *ptr, struct bpf_dynptr *clone__init) __ksym __weak;
> > 
> > +/* Description
> > + *  Copy data from one dynptr to another
> > + * Returns
> > + *  Error code
> > + */
> > +extern int bpf_dynptr_copy(struct bpf_dynptr *dst, __u32 dst_off,
> > +                          struct bpf_dynptr *src, __u32 src_off, __u32 size) __ksym __weak;
> > +
> 
> Do we *need* this? Doesn't all this come from vmlinux.h nowadays?

It does come from vmlinux.h, but this test does not include vmlinux.h
(and compiles a bit faster because of that).

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