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From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Wed, 26 May 2021 09:35:14 -0700
Message-ID: <CAEf4BzZpRL-n0V_JaHrkrOyPgNx+_RR9cQ2fiOfVuQ=Qew11kQ@mail.gmail.com>
Subject: Re: [PATCH bpf v2] libbpf: Move BPF_SEQ_PRINTF and BPF_SNPRINTF to bpf_helpers.h
To:     Florent Revest <revest@chromium.org>
Cc:     Daniel Borkmann <daniel@iogearbox.net>, bpf <bpf@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        KP Singh <kpsingh@kernel.org>,
        Brendan Jackman <jackmanb@google.com>,
        open list <linux-kernel@vger.kernel.org>
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On Wed, May 26, 2021 at 8:01 AM Florent Revest <revest@chromium.org> wrote:
>
> On Wed, May 26, 2021 at 8:35 AM Daniel Borkmann <daniel@iogearbox.net> wrote:
> >
> > On 5/25/21 10:18 PM, Florent Revest wrote:
> > > These macros are convenient wrappers around the bpf_seq_printf and
> > > bpf_snprintf helpers. They are currently provided by bpf_tracing.h which
> > > targets low level tracing primitives. bpf_helpers.h is a better fit.
> > >
> > > The __bpf_narg and __bpf_apply macros are needed in both files so
> > > provided twice and guarded by ifndefs.
> > >
> > > Reported-by: Andrii Nakryiko <andrii@kernel.org>
> > > Signed-off-by: Florent Revest <revest@chromium.org>
> >
> > Given v1/v2 both target bpf tree in the subject, do you really mean bpf or
> > rather bpf-next?
>
> I don't have a preference, it's up to you :)
>
> On one hand, I see no urgency in fixing this: BPF_SEQ_PRINTF has been
> in bpf_tracing.h for a while already so it can wait for another kernel
> release. Applying this to bpf-next would do.
> On the other hand, BPF_SNPRINTF hasn't made it to a kernel release yet
> so we still have a chance to do it right before users start including
> bpf_tracing.h and we'd break them in the next release. That's why I
> tagged it as bpf.
>
> The patch applies cleanly on both trees so if you prefer landing it in
> bpf-next it's fine by me.

I think it should go through bpf-next. It's not really a bug fix. And
we are not going to break anyone with this move. And libbpf 0.4 is
officially released without this change anyway. So, bpf-next.