From mboxrd@z Thu Jan  1 00:00:00 1970
From: Martin KaFai Lau <kafai@fb.com>
Subject: Re: [PATCH bpf-next v5 00/10] BTF: BPF Type Format
Date: Thu, 7 Jun 2018 12:05:10 -0700
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Cc: <netdev@vger.kernel.org>, Alexei Starovoitov <ast@fb.com>,
        Daniel Borkmann <daniel@iogearbox.net>, <kernel-team@fb.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
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On Thu, Jun 07, 2018 at 11:03:37AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Thu, Jun 07, 2018 at 10:54:01AM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Tue, Jun 05, 2018 at 02:25:48PM -0700, Martin KaFai Lau escreveu:
> > > [ btw, the latest commit (1 commit) should be 94a11b59e592 ].
> 
> So, the commit log message for the pahole patch is non-existent:
> 
> https://github.com/iamkafai/pahole/commit/94a11b59e5920908085bfc8d24c92f95c8ffceaf
> 
> we should do better in describing what is done and how, I'm staring
> with a message you sent to the kernel part:
> 
> --
> This patch introduces BPF Type Format (BTF).
> 
> BTF (BPF Type Format) is the meta data format which describes
> the data types of BPF program/map.  Hence, it basically focus
> on the C programming language which the modern BPF is primary
> using.  The first use case is to provide a generic pretty print
> capability for a BPF map.
> --
I will add details in the next github respin/push.

> 
> Now I'm going to do the step-by-step guide on testing the feature just
> introduced, and will try to convert from dwarf to BTF and back, compare
> the pahole output for types encoded in DWARF and BTF, etc.
> 
> If you have something ressembling this already, please share.
The pahole only has the encoder part.  I tested with the verbose output
from the "pahole -V -J".  Loading the btf to the kernel is also tested.