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, 49 insertions, 0 deletions

diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 8330bc0bcb7e..d7ba447db17c 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -19,6 +19,7 @@
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/slab.h>
+#include <net/netdev_queues.h>
 #include <net/netlink.h>
 #include <net/pkt_cls.h>
 #include <net/rtnetlink.h>
@@ -330,6 +331,53 @@ static const struct net_device_ops nsim_vf_netdev_ops = {
 	.ndo_set_features	= nsim_set_features,
 };
 
+/* We don't have true per-queue stats, yet, so do some random fakery here.
+ * Only report stuff for queue 0.
+ */
+static void nsim_get_queue_stats_rx(struct net_device *dev, int idx,
+				    struct netdev_queue_stats_rx *stats)
+{
+	struct rtnl_link_stats64 rtstats = {};
+
+	if (!idx)
+		nsim_get_stats64(dev, &rtstats);
+
+	stats->packets = rtstats.rx_packets - !!rtstats.rx_packets;
+	stats->bytes = rtstats.rx_bytes;
+}
+
+static void nsim_get_queue_stats_tx(struct net_device *dev, int idx,
+				    struct netdev_queue_stats_tx *stats)
+{
+	struct rtnl_link_stats64 rtstats = {};
+
+	if (!idx)
+		nsim_get_stats64(dev, &rtstats);
+
+	stats->packets = rtstats.tx_packets - !!rtstats.tx_packets;
+	stats->bytes = rtstats.tx_bytes;
+}
+
+static void nsim_get_base_stats(struct net_device *dev,
+				struct netdev_queue_stats_rx *rx,
+				struct netdev_queue_stats_tx *tx)
+{
+	struct rtnl_link_stats64 rtstats = {};
+
+	nsim_get_stats64(dev, &rtstats);
+
+	rx->packets = !!rtstats.rx_packets;
+	rx->bytes = 0;
+	tx->packets = !!rtstats.tx_packets;
+	tx->bytes = 0;
+}
+
+static const struct netdev_stat_ops nsim_stat_ops = {
+	.get_queue_stats_tx	= nsim_get_queue_stats_tx,
+	.get_queue_stats_rx	= nsim_get_queue_stats_rx,
+	.get_base_stats		= nsim_get_base_stats,
+};
+
 static void nsim_setup(struct net_device *dev)
 {
 	ether_setup(dev);
@@ -360,6 +408,7 @@ static int nsim_init_netdevsim(struct netdevsim *ns)
 
 	ns->phc = phc;
 	ns->netdev->netdev_ops = &nsim_netdev_ops;
+	ns->netdev->stat_ops = &nsim_stat_ops;
 
 	err = nsim_udp_tunnels_info_create(ns->nsim_dev, ns->netdev);
 	if (err)