Re: [PATCH 2/2] tools build feature: Don't set feature-libcap=1 if libcap-devel isn't available

[Ian Rogers]

On Wed, Dec 11, 2024 at 2:45 PM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
>
> libcap isn't tested in the tools/build/feature/test-all.c fast path
> feature detection process, so don't set it as available if test-all
> manages to build.
>
> There are other users of this feature detection mechanism, and they
> explicitely ask for libcap to be tested, so are not affected by this
> patch, for instance, with this patch in place:
>
>   $ make -C tools/bpf/bpftool/ clean
>   <SNIP>
>   make: Leaving directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'
>   ⬢ [acme@toolbox perf-tools-next]$ make -C tools/bpf/bpftool/
>   make: Entering directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'
>
>   Auto-detecting system features:
>   ...                         clang-bpf-co-re: [ on  ]
>   ...                                    llvm: [ on  ]
>   ...                                  libcap: [ on  ]
>   ...                                  libbfd: [ on  ]
>   ...                             libelf-zstd: [ on  ]
>   <SNIP>
>     LINK    bpftool
>   make: Leaving directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'
>   $
>   $ sudo rpm -e libcap-devel
>   $ make -C tools/bpf/bpftool/
>   <SNIP>
>   make: Entering directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'
>
>   Auto-detecting system features:
>   ...                         clang-bpf-co-re: [ on  ]
>   ...                                    llvm: [ on  ]
>   ...                                  libcap: [ OFF ]
>   ...                                  libbfd: [ on  ]
>   ...                             libelf-zstd: [ on  ]
>
>   $
>
> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Cc: Ian Rogers <irogers@xxxxxxxxxx>
> Cc: James Clark <james.clark@xxxxxxxxxx>
> Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> Cc: Quentin Monnet <qmo@xxxxxxxxxx>
> Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian