Subject: Re: [PATCH net-next 0/2] refactor the ringtest testing for ptr_ring

From: Andy Shevchenko <[email-masked]>
Date: Mon, 5 Jul 2021 21:36:26 +0300

On Mon, Jul 05, 2021 at 02:26:32PM -0400, Michael S. Tsirkin wrote:
> On Mon, Jul 05, 2021 at 08:06:50PM +0800, Yunsheng Lin wrote:
> > On 2021/7/5 17:56, Andy Shevchenko wrote:
> > > On Mon, Jul 05, 2021 at 11:57:33AM +0800, Yunsheng Lin wrote:
> > >> tools/include/* have a lot of abstract layer for building
> > >> kernel code from userspace, so reuse or add the abstract
> > >> layer in tools/include/ to build the ptr_ring for ringtest
> > >> testing.
> > > 
> > > ...
> > > 
> > >>  create mode 100644 tools/include/asm/cache.h
> > >>  create mode 100644 tools/include/asm/processor.h
> > >>  create mode 100644 tools/include/generated/autoconf.h
> > >>  create mode 100644 tools/include/linux/align.h
> > >>  create mode 100644 tools/include/linux/cache.h
> > >>  create mode 100644 tools/include/linux/slab.h
> > > 
> > > Maybe somebody can change this to be able to include in-tree headers directly?
> > 
> > If the above works, maybe the files in tools/include/* is not
> > necessary any more, just use the in-tree headers to compile
> > the user space app?
> > 
> > Or I missed something here?
> 
> why would it work? kernel headers outside of uapi are not
> intended to be consumed by userspace.

The problem here, that we are almost getting two copies of the headers, and
tools are not in a good maintenance, so it's often desynchronized from the
actual Linux headers. This will become more and more diverse if we keep same
way of operation. So, I would rather NAK any new copies of the headers from
include/ to tools/include.

> > > Besides above, had you tested this with `make O=...`?
> > 
> > You are right, the generated/autoconf.h is in another directory
> > with `make O=...`.
> > 
> > Any nice idea to fix the above problem?

-- 
With Best Regards,
Andy Shevchenko