Merge branch 'ynl-tests'

Jakub Kicinski says:

====================
selftests: net: groundwork for YNL-based tests

Currently the options for writing networking tests are C, bash or
some mix of the two. YAML/Netlink gives us the ability to easily
interface with Netlink in higher level laguages. In particular,
there is a Python library already available in tree, under tools/net.
Add the scaffolding which allows writing tests using this library.

The "scaffolding" is needed because the library lives under
tools/net and uses YAML files from under Documentation/.
So we need a small amount of glue code to find those things
and add them to TEST_FILES.

This series adds both a basic SW sanity test and driver
test which can be run against netdevsim or a real device.
When I develop core code I usually test with netdevsim,
then a real device, and then a backport to Meta's kernel.
Because of the lack of integration, until now I had
to throw away the (YNL-based) test script and netdevsim code.

Running tests in tree directly:

 $ ./tools/testing/selftests/net/nl_netdev.py
 KTAP version 1
 1..2
 ok 1 nl_netdev.empty_check
 ok 2 nl_netdev.lo_check
 # Totals: pass:2 fail:0 xfail:0 xpass:0 skip:0 error:0

in tree via make:

 $ make -C tools/testing/selftests/ TARGETS=net \
	TEST_PROGS=nl_netdev.py TEST_GEN_PROGS="" run_tests
  [ ... ]

and installed externally, all seem to work:

 $ make -C tools/testing/selftests/ TARGETS=net \
	install INSTALL_PATH=/tmp/ksft-net
 $ /tmp/ksft-net/run_kselftest.sh -t net:nl_netdev.py
  [ ... ]

For driver tests I followed the lead of net/forwarding and
get the device name from env and/or a config file.

v3:
 - fix up netdevsim C
 - various small nits in other patches (see changelog in patches)
v2: https://lore.kernel.org/all/20240403023426.1762996-1-kuba@kernel.org/
 - don't add to TARGETS, create a deperate variable with deps
 - support and use with
 - support and use passing arguments to tests
v1: https://lore.kernel.org/all/20240402010520.1209517-1-kuba@kernel.org/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 86 insertions, 0 deletions

diff --git a/tools/testing/selftests/drivers/net/stats.py b/tools/testing/selftests/drivers/net/stats.py
new file mode 100755
index 000000000000..5a9d4e56b28b
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/stats.py
@@ -0,0 +1,86 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+from lib.py import ksft_run, ksft_in, ksft_true, KsftSkipEx, KsftXfailEx
+from lib.py import EthtoolFamily, NetdevFamily, RtnlFamily, NlError
+from lib.py import NetDrvEnv
+
+ethnl = EthtoolFamily()
+netfam = NetdevFamily()
+rtnl = RtnlFamily()
+
+
+def check_pause(cfg) -> None:
+    global ethnl
+
+    try:
+        ethnl.pause_get({"header": {"dev-index": cfg.ifindex}})
+    except NlError as e:
+        if e.error == 95:
+            raise KsftXfailEx("pause not supported by the device")
+        raise
+
+    data = ethnl.pause_get({"header": {"dev-index": cfg.ifindex,
+                                       "flags": {'stats'}}})
+    ksft_true(data['stats'], "driver does not report stats")
+
+
+def check_fec(cfg) -> None:
+    global ethnl
+
+    try:
+        ethnl.fec_get({"header": {"dev-index": cfg.ifindex}})
+    except NlError as e:
+        if e.error == 95:
+            raise KsftXfailEx("FEC not supported by the device")
+        raise
+
+    data = ethnl.fec_get({"header": {"dev-index": cfg.ifindex,
+                                     "flags": {'stats'}}})
+    ksft_true(data['stats'], "driver does not report stats")
+
+
+def pkt_byte_sum(cfg) -> None:
+    global netfam, rtnl
+
+    def get_qstat(test):
+        global netfam
+        stats = netfam.qstats_get({}, dump=True)
+        if stats:
+            for qs in stats:
+                if qs["ifindex"]== test.ifindex:
+                    return qs
+
+    qstat = get_qstat(cfg)
+    if qstat is None:
+        raise KsftSkipEx("qstats not supported by the device")
+
+    for key in ['tx-packets', 'tx-bytes', 'rx-packets', 'rx-bytes']:
+        ksft_in(key, qstat, "Drivers should always report basic keys")
+
+    # Compare stats, rtnl stats and qstats must match,
+    # but the interface may be up, so do a series of dumps
+    # each time the more "recent" stats must be higher or same.
+    def stat_cmp(rstat, qstat):
+        for key in ['tx-packets', 'tx-bytes', 'rx-packets', 'rx-bytes']:
+            if rstat[key] != qstat[key]:
+                return rstat[key] - qstat[key]
+        return 0
+
+    for _ in range(10):
+        rtstat = rtnl.getlink({"ifi-index": cfg.ifindex})['stats']
+        if stat_cmp(rtstat, qstat) < 0:
+            raise Exception("RTNL stats are lower, fetched later")
+        qstat = get_qstat(cfg)
+        if stat_cmp(rtstat, qstat) > 0:
+            raise Exception("Qstats are lower, fetched later")
+
+
+def main() -> None:
+    with NetDrvEnv(__file__) as cfg:
+        ksft_run([check_pause, check_fec, pkt_byte_sum],
+                 args=(cfg, ))
+
+
+if __name__ == "__main__":
+    main()