Re: [PATCH v2 net-next 05/14] selftests: xsk: move the AF_XDP test suite to selftests/net

[Maciej Fijalkowski <maciej.fijalkowski@intel.com>]

On Fri, Oct 09, 2026 at 01:18:10PM +0200, Björn Töpel wrote:
> Maciej Fijalkowski <maciej.fijalkowski@intel.com> writes:
> 
> > Move the xskxceiver engine, the AF_XDP userspace library, the test
> > definitions and the XDP program to net/lib/xsk, and the veth launcher
> > test_xsk.sh with its prerequisites script to selftests/net. A later
> > patch drives the same engine against real NICs from drivers/net/hw, and
> > net/lib is where both suites already take shared helpers from, so the
> > binary does not need a second copy.
> >
> > net/lib builds xskxceiver together with its XDP program and skeleton,
> > using the bpftool in PATH, and skips it with a warning when bpftool is
> > missing or does not run, so the rest of net/lib still builds.
> > selftests/net installs test_xsk.sh, which runs lib/xskxceiver.
> >
> > Like the rest of net/lib, xskxceiver builds against the installed uapi
> > headers rather than the tools/include/uapi copies that the bpf selftests
> > use. xskxceiver.c got min_t() only because the tools copy of
> > linux/netlink.h includes linux/kernel.h, so include linux/kernel.h
> > directly.
> >
> > Move the two ethtool ring helpers from network_helpers into xsk.c so the
> > engine no longer depends on network_helpers, and point the kselftest.h
> > include of test_xsk.h at the net/lib include path. The XDP program moves
> > unchanged. Its Ethernet header bound check compares pointers of distinct
> > types, so net/lib builds it with -Wno-compare-distinct-pointer-types, as
> > the bpf selftests do.
> >
> > xdp_hw_metadata and the test_progs xdp_metadata test keep using xsk.c
> > and xsk.h from their new location.
> >
> > Point the AF_XDP entry in MAINTAINERS at the new paths.
> >
> > Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
> > ---
> >  Documentation/networking/af_xdp.rst           |  6 +--
> >  MAINTAINERS                                   |  3 +-
> >  tools/testing/selftests/bpf/.gitignore        |  1 -
> >  tools/testing/selftests/bpf/Makefile          | 29 +++++------
> >  tools/testing/selftests/bpf/network_helpers.c | 48 ------------------
> >  tools/testing/selftests/bpf/network_helpers.h |  2 -
> >  tools/testing/selftests/net/Makefile          |  2 +
> >  tools/testing/selftests/net/config            |  1 +
> >  tools/testing/selftests/net/lib/.gitignore    |  2 +
> >  tools/testing/selftests/net/lib/Makefile      | 34 +++++++++++++
> >  .../prog_tests => net/lib/xsk}/test_xsk.c     |  2 +-
> >  .../prog_tests => net/lib/xsk}/test_xsk.h     |  2 +-
> >  .../selftests/{bpf => net/lib/xsk}/xsk.c      | 49 ++++++++++++++++++-
> >  .../selftests/{bpf => net/lib/xsk}/xsk.h      |  4 ++
> >  .../{bpf => net/lib/xsk}/xsk_xdp_common.h     |  0
> >  .../lib/xsk/xsk_xdp_progs.bpf.c}              |  0
> >  .../{bpf => net/lib/xsk}/xskxceiver.c         |  7 +--
> >  .../{bpf => net/lib/xsk}/xskxceiver.h         |  0
> >  .../selftests/{bpf => net}/test_xsk.sh        |  0
> 
> I would not carry the test_xsk.sh over. Just do a Python variant, like
> the drivers/net/hw/xsk.py, but for net instead. Look at the the
> nk_lease.py pair for inspiration.
> 
> It's just a cogitive load switch between Python and bash. We're starting
> out fresh(ish) here.
> 
> The Python ksft world gives us a lot for free.

Plan was to move fast as you wanted + watch the code churn not to blow
off. I assume now it's better to take some time and do things right from
the start.

> 
> 
> Björn