[PATCH net-next v14 13/13] selftests: add ncdevmem, netcat for devmem TCP

[Mina Almasry]

On Thu, Jun 27, 2024 at 12:55 PM Mina Almasry <almasrymina at google.com> wrote:
>
> On Wed, Jun 26, 2024 at 5:46 PM Jakub Kicinski <kuba at kernel.org> wrote:
> >
> > On Wed, 26 Jun 2024 15:08:22 -0700 Jakub Kicinski wrote:
> > > On Tue, 25 Jun 2024 19:54:01 +0000 Mina Almasry wrote:
> > > > +CFLAGS += -I../../../net/ynl/generated/
> > > > +CFLAGS += -I../../../net/ynl/lib/
> > > > +
> > > > +LDLIBS += ../../../net/ynl/lib/ynl.a ../../../net/ynl/generated/protos.a
> > >
> > > Not as easy as this.. Please add this commit to your series:
> > > https://github.com/kuba-moo/linux/commit/c130e8cc7208be544ec4f6f3627f1d36875d8c47
> > >
> > > And here's an example of how you then use ynl.mk to code gen and build
> > > for desired families (note the ordering of variables vs includes,
> > > I remember that part was quite inflexible..):
> > > https://github.com/kuba-moo/linux/commit/5d357f97ccd0248ca6136c5e11ca3eadf5091bb3
> >
> > Investigating this further my patches will not work for O=xyz builds
> > either. Please squash this into the relevant changes:
> >
>
> Thanks! I cherry-picked commit 15dbefa97fb98 ("tools: net: package
> libynl for use in selftests"), and then applied the diff below to the
> series [1].
>
> Now:
>
> `git clean -fdx && make  headers_install && make -C
> ./tools/testing/selftests/net` works
>
> `git clean -fdx && make  headers_install && make -C
> ./tools/testing/selftests/net ncdevmem` doesn't work with this error:
>
> make: Entering directory
> '/usr/local/google/home/almasrymina/cos-kernel/tools/testing/selftests/net'
> gcc -Wall -Wl,--no-as-needed -O2 -g -I../../../../usr/include/
> -isystem /usr/local/google/home/almasrymina/cos-kernel/tools/testing/selftests/../../../usr/include
> -I../     ncdevmem.c  -lmnl -o ncdevmem
> ncdevmem.c:34:10: fatal error: netdev-user.h: No such file or directory
>    34 | #include "netdev-user.h"
>       |          ^~~~~~~~~~~~~~~
> compilation terminated.
> make: *** [<builtin>: ncdevmem] Error 1
>
> It seems specifying the target doesn't trigger the libynl.a to be
> built. Isn't this a bug, or is that expected?

Nevermind, from a closer look at the docs, it looks like the proper
way to build one test is:

`make -C ./tools/testing/selftests/net TARGETS=ncdevmem`, which works.

`make -C ./tools/testing/selftests/net ncdevmem` was just a weird way
I was building the tests that worked for me, but it doesn't actually
show up in the docs. I'm guessing I can ignore the failure.

-- 
Thanks,
Mina