[PATCH v1 2/2] net: selftest: add test for netdev netlink queue-get API

[David Wei <dw@davidwei.uk>]

Add a selftest for Netdev Netlink queue-get API. The ground truth is
determined by sysfs.

The test works with netdevsim by default or with a real device by
setting NETIF.

Minor changes to NetdevSimDev to accept the number of queues to create
per port and pass through NetdevSimDev args in NetDrvEnv ctor.

Signed-off-by: David Wei <dw@davidwei.uk>
---
 tools/testing/selftests/drivers/net/Makefile  |  1 +
 .../selftests/drivers/net/lib/py/env.py       | 10 ++-
 tools/testing/selftests/drivers/net/queues.py | 67 +++++++++++++++++++
 tools/testing/selftests/net/lib/py/nsim.py    |  4 +-
 4 files changed, 78 insertions(+), 4 deletions(-)
 create mode 100755 tools/testing/selftests/drivers/net/queues.py

diff --git a/tools/testing/selftests/drivers/net/Makefile b/tools/testing/selftests/drivers/net/Makefile
index 379cdb1960a7..118a73650dbc 100644
--- a/tools/testing/selftests/drivers/net/Makefile
+++ b/tools/testing/selftests/drivers/net/Makefile
@@ -3,5 +3,6 @@
 TEST_INCLUDES := $(wildcard lib/py/*.py)
 
 TEST_PROGS := stats.py
+TEST_PROGS += queues.py
 
 include ../../lib.mk
diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py
index e1abe9491daf..7187aca5c516 100644
--- a/tools/testing/selftests/drivers/net/lib/py/env.py
+++ b/tools/testing/selftests/drivers/net/lib/py/env.py
@@ -7,7 +7,7 @@ from lib.py import ip
 from lib.py import NetdevSimDev
 
 class NetDrvEnv:
-    def __init__(self, src_path):
+    def __init__(self, src_path, **kwargs):
         self._ns = None
 
         self.env = os.environ.copy()
@@ -16,7 +16,7 @@ class NetDrvEnv:
         if 'NETIF' in self.env:
             self.dev = ip("link show dev " + self.env['NETIF'], json=True)[0]
         else:
-            self._ns = NetdevSimDev()
+            self._ns = NetdevSimDev(**kwargs)
             self.dev = self._ns.nsims[0].dev
         self.ifindex = self.dev['ifindex']
 
@@ -50,3 +50,9 @@ class NetDrvEnv:
             else:
                 self.env[k] = token
                 k = None
+
+    def dev_up(self):
+        ip(f"link set dev {self.dev['ifname']} up")
+
+    def dev_down(self):
+        ip(f"link set dev {self.dev['ifname']} down")
diff --git a/tools/testing/selftests/drivers/net/queues.py b/tools/testing/selftests/drivers/net/queues.py
new file mode 100755
index 000000000000..de2820f2759a
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/queues.py
@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+from lib.py import ksft_run, ksft_in, ksft_true, ksft_eq, KsftSkipEx, KsftXfailEx
+from lib.py import NetdevFamily, NlError
+from lib.py import NetDrvEnv
+from lib.py import cmd
+import glob
+
+netnl = NetdevFamily()
+
+
+def sys_get_queues(ifname) -> int:
+    folders = glob.glob(f'/sys/class/net/{ifname}/queues/rx-*')
+    return len(folders)
+
+
+def nl_get_queues(cfg):
+    global netnl
+    queues = netnl.queue_get({'ifindex': cfg.ifindex}, dump=True)
+    if queues:
+        return len([q for q in queues if q['type'] == 'rx'])
+    return None
+
+
+def get_queues(cfg) -> None:
+    global netnl
+
+    queues = nl_get_queues(cfg)
+    if not queues:
+        raise KsftSkipEx("queue-get not supported by device")
+
+    expected = sys_get_queues(cfg.dev['ifname'])
+    ksft_eq(queues, expected)
+
+
+def addremove_queues(cfg) -> None:
+    global netnl
+
+    queues = nl_get_queues(cfg)
+    if not queues:
+        raise KsftSkipEx("queue-get not supported by device")
+
+    expected = sys_get_queues(cfg.dev['ifname'])
+    ksft_eq(queues, expected)
+
+    # reduce queue count by 1
+    expected = expected - 1
+    cmd(f"ethtool -L {cfg.dev['ifname']} combined {expected}")
+    queues = nl_get_queues(cfg)
+    ksft_eq(queues, expected)
+
+    # increase queue count by 1
+    expected = expected + 1
+    cmd(f"ethtool -L {cfg.dev['ifname']} combined {expected}")
+    queues = nl_get_queues(cfg)
+    ksft_eq(queues, expected)
+
+
+def main() -> None:
+    with NetDrvEnv(__file__, queue_count=3) as cfg:
+        cfg.dev_up()
+        ksft_run([get_queues, addremove_queues], args=(cfg, ))
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/testing/selftests/net/lib/py/nsim.py b/tools/testing/selftests/net/lib/py/nsim.py
index 06896cdf7c18..f571a8b3139b 100644
--- a/tools/testing/selftests/net/lib/py/nsim.py
+++ b/tools/testing/selftests/net/lib/py/nsim.py
@@ -49,7 +49,7 @@ class NetdevSimDev:
         with open(fullpath, "w") as f:
             f.write(val)
 
-    def __init__(self, port_count=1, ns=None):
+    def __init__(self, port_count=1, queue_count=1, ns=None):
         # nsim will spawn in init_net, we'll set to actual ns once we switch it there
         self.ns = None
 
@@ -59,7 +59,7 @@ class NetdevSimDev:
         addr = random.randrange(1 << 15)
         while True:
             try:
-                self.ctrl_write("new_device", "%u %u" % (addr, port_count))
+                self.ctrl_write("new_device", "%u %u %u" % (addr, port_count, queue_count))
             except OSError as e:
                 if e.errno == errno.ENOSPC:
                     addr = random.randrange(1 << 15)
-- 
2.43.0