Re: [PATCH bpf-next v3 00/11] tools: Use consistent libbpf include paths everywhere

[Alexei Starovoitov]

On Thu, Jan 16, 2020 at 02:22:11PM +0100, Toke Høiland-Jørgensen wrote:
> The recent commit 6910d7d3867a ("selftests/bpf: Ensure bpf_helper_defs.h are
> taken from selftests dir") broke compilation against libbpf if it is installed
> on the system, and $INCLUDEDIR/bpf is not in the include path.
> 
> Since having the bpf/ subdir of $INCLUDEDIR in the include path has never been a
> requirement for building against libbpf before, this needs to be fixed. One
> option is to just revert the offending commit and figure out a different way to
> achieve what it aims for. 

The offending commit has been in the tree for a week. So I applied Andrii's
revert of that change. It reintroduced the build dependency issue, but we lived
with it for long time, so we can take time to fix it cleanly.
I suggest to focus on that build dependency first.

> However, this series takes a different approach:
> Changing all in-tree users of libbpf to consistently use a bpf/ prefix in
> #include directives for header files from libbpf.

I'm not sure it's a good idea. It feels nice, but think of a message we're
sending to everyone. We will get spamed with question: does bpf community
require all libbpf users to use bpf/ prefix ? What should be our answer?
Require or recommend? If require.. what for? It works as-is. If recommend then
why suddenly we're changing all files in selftests and samples?
There is no good answer here. I think we should leave the things as-is.
And fix build dep differently.

Patches 1-3 are still worth doing.