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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Wed, 27 Nov 2019 16:31:41 -0800
Message-ID: <CAADnVQJCMpke49NNzy33EKdwpW+SY1orTm+0f0b-JuW8+uA7Yw@mail.gmail.com>
Subject: Re: [PATCH] libbpf: Fix up generation of bpf_helper_defs.h
To:     Arnaldo Carvalho de Melo <acme@kernel.org>
Cc:     Jakub Kicinski <jakub.kicinski@netronome.com>,
        Stanislav Fomichev <sdf@fomichev.me>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>,
        Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>,
        =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= <toke@redhat.com>,
        Andrii Nakryiko <andriin@fb.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Jiri Olsa <jolsa@kernel.org>, Martin KaFai Lau <kafai@fb.com>,
        Namhyung Kim <namhyung@kernel.org>, bpf <bpf@vger.kernel.org>,
        Networking <netdev@vger.kernel.org>,
        linux-perf-users@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Quentin Monnet <quentin.monnet@netronome.com>
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On Tue, Nov 26, 2019 at 5:39 PM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Tue, Nov 26, 2019 at 03:52:28PM -0800, Jakub Kicinski escreveu:
> > On Tue, 26 Nov 2019 15:10:30 -0800, Stanislav Fomichev wrote:
> > > We are using this script with python2.7, works just fine :-)
> > > So maybe doing s/python3/python/ is the way to go, whatever
> > > default python is installed, it should work with that.
>
> > That increases the risk someone will make a python2-only change
> > and break Python 3.
>
> > Python 2 is dead, I'm honestly surprised this needs to be said :)
>
> It shouldn't have to be said, and probably it is old school to try and
> keep things portable when there is no need to use new stuff for simple
> tasks like this.
>
> Anyway, it seems its just a matter of adding the python3 package to the
> old container images and then most of them will work with what is in
> that script, what doesn't work is really old and then NO_LIBBPF=1 is the
> way to go.
>
> In the end, kinda nothing to see here, go back to adding cool new stuff,
> lets not hold eBPF from progressing ;-P

Absolutely. I think if some distro is still using 32-bit userland it's likely
so much behind anything modern that its kernel is equally old too
and appeal of new features (bpf or anything else) is probably low.
So if I were you I would keep 32-bit builds of perf supported, but with
minimal effort.

Re: patch itself.
I can take it as-is into bpf tree and it will be in Linus's tree in few days.
Or I can take only tools/lib/bpf/Makefile hunk and you can take
tools/perf/MANIFEST via perf tree?
Whichever way is fine.