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Date:   Fri, 22 Jun 2018 11:43:12 -0700
From:   Jakub Kicinski <jakub.kicinski@netronome.com>
To:     Okash Khawaja <osk@fb.com>
Cc:     Martin KaFai Lau <kafai@fb.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Alexei Starovoitov <ast@kernel.org>,
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        "David S. Miller" <davem@davemloft.net>, <netdev@vger.kernel.org>,
        <kernel-team@fb.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH bpf-next 2/3] bpf: btf: add btf json print functionality
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On Fri, 22 Jun 2018 12:17:52 +0100, Okash Khawaja wrote:
> > > > > > > The name XYZ_struct may not be the best, perhaps you can come up with a
> > > > > > > better one?  
> > > > > > > 
> > > > > > > Does that make sense?  Am I missing what you're doing here?
> > > > > > > 
> > > > > > > One process note - please make sure you run checkpatch.pl --strict on
> > > > > > > bpftool patches before posting.
> > > > > > > 
> > > > > > > Thanks for working on this!      
> > >   
> 
> Hi,
> 
> While I agree on the point of backward compatibility, I think printing
> two overlapping pieces of information side-by-side will make the
> interface less clear. Having separate outputs for the two will keep the
> interface clear and readable.
> 
> Is there a major downside to adding a new flag for BTF output?

plain output and JSON should be more or less equivalent, just formatted
differently.  If we hide the BTF-ed JSON under some flag most users
will just run bpftool -jp map dump id X, see BTF is not there and move
on, without ever looking into the man page to discover there is a magic
switch...