Re: [PATCH bpf-next v5 00/11] tools: Use consistent libbpf include paths everywhere

[Alexei Starovoitov]

On Mon, Jan 20, 2020 at 2:21 PM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Mon, Jan 20, 2020 at 5:08 AM Toke HÃiland-JÃrgensen <toke@xxxxxxxxxx> wrote:
> >
> > We are currently being somewhat inconsistent with the libbpf include paths,
> > which makes it difficult to move files from the kernel into an external
> > libbpf-using project without adjusting include paths.
> >
> > Having the bpf/ subdir of $INCLUDEDIR in the include path has never been a
> > requirement for building against libbpf before, and indeed the libbpf pkg-config
> > file doesn't include it. So let's make all libbpf includes across the kernel
> > tree use the bpf/ prefix in their includes. Since bpftool skeleton generation
> > emits code with a libbpf include, this also ensures that those can be used in
> > existing external projects using the regular pkg-config include path.
> >
> > This turns out to be a somewhat invasive change in the number of files touched;
> > however, the actual changes to files are fairly trivial (most of them are simply
> > made with 'sed'). The series is split to make the change for one tool subdir at
> > a time, while trying not to break the build along the way. It is structured like
> > this:
> >
> > - Patch 1-3: Trivial fixes to Makefiles for issues I discovered while changing
> >   the include paths.
> >
> > - Patch 4-8: Change the include directives to use the bpf/ prefix, and updates
> >   Makefiles to make sure tools/lib/ is part of the include path, but without
> >   removing tools/lib/bpf
> >
> > - Patch 9-11: Remove tools/lib/bpf from include paths to make sure we don't
> >   inadvertently re-introduce includes without the bpf/ prefix.
> >
> > Changelog:
> >
> > v5:
> >   - Combine the libbpf build rules in selftests Makefile (using Andrii's
> >     suggestion for a make rule).
> >   - Re-use self-tests libbpf build for runqslower (new patch 10)
> >   - Formatting fixes
> >
> > v4:
> >   - Move runqslower error on missing BTF into make rule
> >   - Make sure we don't always force a rebuild selftests
> >   - Rebase on latest bpf-next (dropping patch 11)
> >
> > v3:
> >   - Don't add the kernel build dir to the runqslower Makefile, pass it in from
> >     selftests instead.
> >   - Use libbpf's 'make install_headers' in selftests instead of trying to
> >     generate bpf_helper_defs.h in-place (to also work on read-only filesystems).
> >   - Use a scratch builddir for both libbpf and bpftool when building in selftests.
> >   - Revert bpf_helpers.h to quoted include instead of angled include with a bpf/
> >     prefix.
> >   - Fix a few style nits from Andrii
> >
> > v2:
> >   - Do a full cleanup of libbpf includes instead of just changing the
> >     bpf_helper_defs.h include.
> >
> > ---
> >
>
> Looks good, it's a clear improvement on what we had before, thanks!
>
> It doesn't re-build bpftool when bpftool sources changes, but I think
> it was like that even before, so no need to block on that. Would be
> nice to have a follow up fixing that, though. $(wildcard
> $(BPFTOOL_DIR)/*.[ch] $(BPFTOOL_DIR)/Makefile) should do it, same as
> for libbpf.
>
> So, for the series:
>
> Acked-by: Andrii Nakryiko <andriin@xxxxxx>
> Tested-by: Andrii Nakryiko <andriin@xxxxxx>

Applied. Thanks