selftests: drv-net: wait for carrier

On fast machines the tests run in quick succession so even
when tests clean up after themselves the carrier may need
some time to come back.

Specifically in NIPA when ping.py runs right after netpoll_basic.py
the first ping command fails.

Since the context manager callbacks are now common NetDrvEpEnv
gets an ip link up call as well.

Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20250812142054.750282-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/tools/testing/selftests/drivers/net/lib/py/__init__.py b/tools/testing/selftests/drivers/net/lib/py/__init__.py
index 8711c67ad658a704c94a97a9871fc8959685115c..a07b56a75c8a6fad942628f8be82cbbe3f309f52 100644 (file)
--- a/tools/testing/selftests/drivers/net/lib/py/__init__.py
+++ b/tools/testing/selftests/drivers/net/lib/py/__init__.py
@@ -15,7 +15,7 @@ try:
         NlError, RtnlFamily, DevlinkFamily
     from net.lib.py import CmdExitFailure
     from net.lib.py import bkg, cmd, bpftool, bpftrace, defer, ethtool, \
-        fd_read_timeout, ip, rand_port, tool, wait_port_listen
+        fd_read_timeout, ip, rand_port, tool, wait_port_listen, wait_file
     from net.lib.py import fd_read_timeout
     from net.lib.py import KsftSkipEx, KsftFailEx, KsftXfailEx
     from net.lib.py import ksft_disruptive, ksft_exit, ksft_pr, ksft_run, \

diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py
index 1b8bd648048f74463da120fced579df86a5b8aa5..c1f3b608c6d8fca4c00af4872bb8d059e4f5615b 100644 (file)
--- a/tools/testing/selftests/drivers/net/lib/py/env.py
+++ b/tools/testing/selftests/drivers/net/lib/py/env.py
@@ -4,7 +4,7 @@ import os
 import time
 from pathlib import Path
 from lib.py import KsftSkipEx, KsftXfailEx
-from lib.py import ksft_setup
+from lib.py import ksft_setup, wait_file
 from lib.py import cmd, ethtool, ip, CmdExitFailure
 from lib.py import NetNS, NetdevSimDev
 from .remote import Remote
@@ -25,6 +25,9 @@ class NetDrvEnvBase:
 
         self.env = self._load_env_file()
 
+        # Following attrs must be set be inheriting classes
+        self.dev = None
+
     def _load_env_file(self):
         env = os.environ.copy()
 
@@ -48,6 +51,22 @@ class NetDrvEnvBase:
                 env[pair[0]] = pair[1]
         return ksft_setup(env)
 
+    def __del__(self):
+        pass
+
+    def __enter__(self):
+        ip(f"link set dev {self.dev['ifname']} up")
+        wait_file(f"/sys/class/net/{self.dev['ifname']}/carrier",
+                  lambda x: x.strip() == "1")
+
+        return self
+
+    def __exit__(self, ex_type, ex_value, ex_tb):
+        """
+        __exit__ gets called at the end of a "with" block.
+        """
+        self.__del__()
+
 
 class NetDrvEnv(NetDrvEnvBase):
     """
@@ -72,17 +91,6 @@ class NetDrvEnv(NetDrvEnvBase):
         self.ifname = self.dev['ifname']
         self.ifindex = self.dev['ifindex']
 
-    def __enter__(self):
-        ip(f"link set dev {self.dev['ifname']} up")
-
-        return self
-
-    def __exit__(self, ex_type, ex_value, ex_tb):
-        """
-        __exit__ gets called at the end of a "with" block.
-        """
-        self.__del__()
-
     def __del__(self):
         if self._ns:
             self._ns.remove()
@@ -219,15 +227,6 @@ class NetDrvEpEnv(NetDrvEnvBase):
             raise Exception("Can't resolve remote interface name, multiple interfaces match")
         return v6[0]["ifname"] if v6 else v4[0]["ifname"]
 
-    def __enter__(self):
-        return self
-
-    def __exit__(self, ex_type, ex_value, ex_tb):
-        """
-        __exit__ gets called at the end of a "with" block.
-        """
-        self.__del__()
-
     def __del__(self):
         if self._ns:
             self._ns.remove()

diff --git a/tools/testing/selftests/net/lib/py/utils.py b/tools/testing/selftests/net/lib/py/utils.py
index 4ac9249c85abcec1d712dc82118430a8c859397b..b188cac49738ffa0d603ddfea2ec6021d1c2fa13 100644 (file)
--- a/tools/testing/selftests/net/lib/py/utils.py
+++ b/tools/testing/selftests/net/lib/py/utils.py
@@ -252,3 +252,21 @@ def wait_port_listen(port, proto="tcp", ns=None, host=None, sleep=0.005, deadlin
         if time.monotonic() > end:
             raise Exception("Waiting for port listen timed out")
         time.sleep(sleep)
+
+
+def wait_file(fname, test_fn, sleep=0.005, deadline=5, encoding='utf-8'):
+    """
+    Wait for file contents on the local system to satisfy a condition.
+    test_fn() should take one argument (file contents) and return whether
+    condition is met.
+    """
+    end = time.monotonic() + deadline
+
+    with open(fname, "r", encoding=encoding) as fp:
+        while True:
+            if test_fn(fp.read()):
+                break
+            fp.seek(0)
+            if time.monotonic() > end:
+                raise TimeoutError("Wait for file contents failed", fname)
+            time.sleep(sleep)