Merge branch 'selftests: xsk: add busy-poll testing plus various fixes'

Merge branch 'selftests: xsk: add busy-poll testing plus various fixes'

Magnus Karlsson says:

====================

This patch set adds busy-poll testing to the xsk selftests. It runs
exactly the same tests as with regular softirq processing, but with
busy-poll enabled. I have also included a number of fixes to the
selftests that have been bugging me for a while or was discovered
while implementing the busy-poll support. In summary these are:

* Fix the error reporting of failed tests. Each failed test used to be
  reported as both failed and passed, messing up things.

* Added a summary test printout at the end of the test suite so that
  users do not have to scroll up and look at the result of both the
  softirq run and the busy_poll run.

* Added a timeout to the tests, so that if a test locks up, we report
  a fail and still get to run all the other tests.

* Made the stats test just look and feel like all the other
  tests. Makes the code simpler and the test reporting more
  consistent. These are the 3 last commits.

* Replaced zero length packets with packets of 64 byte length. This so
  that some of the tests will pass after commit 726e2c5929de84 ("veth:
  Ensure eth header is in skb's linear part").

* Added clean-up of the veth pair when terminating the test run.

* Some smaller clean-ups of unused stuff.

Note, to pass the busy-poll tests commit 8de8b71b787f ("xsk: Fix
l2fwd for copy mode + busy poll combo") need to be present. It is
present in bpf but not yet in bpf-next.

Thanks: Magnus
====================

Acked-by: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>