Merge branch 'selftests-drv-net-convert-so_txtime-to-drv-net'

Willem de Bruijn says:

====================
selftests: drv-net: convert so_txtime to drv-net

In preparation for extending to pacing hardware offload, convert the
so_txtime.sh test to a drv-net test that can be run against netdevsim
and real hardware.

Two preparatory patches
1. support negative tests, where tests are expected to fail
2. add a tc helper

See individual patches for details and detailed changelog
====================

Link: https://patch.msgid.link/20260504174056.565319-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

11 files changed, 166 insertions, 133 deletions

diff --git a/tools/testing/selftests/drivers/net/.gitignore b/tools/testing/selftests/drivers/net/.gitignore
index 585ecb4d5dc4..e5314ce4bb2d 100644
--- a/tools/testing/selftests/drivers/net/.gitignore
+++ b/tools/testing/selftests/drivers/net/.gitignore
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 napi_id_helper
 psp_responder
+so_txtime
diff --git a/tools/testing/selftests/drivers/net/Makefile b/tools/testing/selftests/drivers/net/Makefile
index b72080c6d06b..d5bf4cb638a8 100644
--- a/tools/testing/selftests/drivers/net/Makefile
+++ b/tools/testing/selftests/drivers/net/Makefile
@@ -7,6 +7,7 @@ TEST_INCLUDES := $(wildcard lib/py/*.py) \
 
 TEST_GEN_FILES := \
 	napi_id_helper \
+	so_txtime \
 # end of TEST_GEN_FILES
 
 TEST_PROGS := \
@@ -21,6 +22,7 @@ TEST_PROGS := \
 	queues.py \
 	ring_reconfig.py \
 	shaper.py \
+	so_txtime.py \
 	stats.py \
 	xdp.py \
 # end of TEST_PROGS
diff --git a/tools/testing/selftests/drivers/net/config b/tools/testing/selftests/drivers/net/config
index fd16994366f4..2309109a94ec 100644
--- a/tools/testing/selftests/drivers/net/config
+++ b/tools/testing/selftests/drivers/net/config
@@ -8,5 +8,7 @@ CONFIG_NETCONSOLE=m
 CONFIG_NETCONSOLE_DYNAMIC=y
 CONFIG_NETCONSOLE_EXTENDED_LOG=y
 CONFIG_NETDEVSIM=m
+CONFIG_NET_SCH_ETF=m
+CONFIG_NET_SCH_FQ=m
 CONFIG_VLAN_8021Q=m
 CONFIG_XDP_SOCKETS=y
diff --git a/tools/testing/selftests/drivers/net/lib/py/__init__.py b/tools/testing/selftests/drivers/net/lib/py/__init__.py
index 2b5ec0505672..09aac4ce67bc 100644
--- a/tools/testing/selftests/drivers/net/lib/py/__init__.py
+++ b/tools/testing/selftests/drivers/net/lib/py/__init__.py
@@ -23,7 +23,8 @@ try:
         NlError, RtnlFamily, DevlinkFamily, PSPFamily, Netlink
     from net.lib.py import CmdExitFailure
     from net.lib.py import bkg, cmd, bpftool, bpftrace, defer, ethtool, \
-        fd_read_timeout, ip, rand_port, rand_ports, wait_port_listen, wait_file
+        fd_read_timeout, ip, rand_port, rand_ports, tc, wait_port_listen, \
+        wait_file
     from net.lib.py import bpf_map_set, bpf_map_dump, bpf_prog_map_ids
     from net.lib.py import KsftSkipEx, KsftFailEx, KsftXfailEx
     from net.lib.py import ksft_disruptive, ksft_exit, ksft_pr, ksft_run, \
@@ -36,7 +37,7 @@ try:
                "NlError", "RtnlFamily", "DevlinkFamily", "PSPFamily", "Netlink",
                "CmdExitFailure",
                "bkg", "cmd", "bpftool", "bpftrace", "defer", "ethtool",
-               "fd_read_timeout", "ip", "rand_port", "rand_ports",
+               "fd_read_timeout", "ip", "rand_port", "rand_ports", "tc",
                "wait_port_listen", "wait_file",
                "bpf_map_set", "bpf_map_dump", "bpf_prog_map_ids",
                "KsftSkipEx", "KsftFailEx", "KsftXfailEx",
diff --git a/tools/testing/selftests/net/so_txtime.c b/tools/testing/selftests/drivers/net/so_txtime.c
index b76df1efc2ef..b6930883569b 100644
--- a/tools/testing/selftests/net/so_txtime.c
+++ b/tools/testing/selftests/drivers/net/so_txtime.c
@@ -33,6 +33,8 @@
 #include <unistd.h>
 #include <poll.h>
 
+#include "kselftest.h"
+
 static int	cfg_clockid	= CLOCK_TAI;
 static uint16_t	cfg_port	= 8000;
 static int	cfg_variance_us	= 4000;
@@ -43,6 +45,8 @@ static bool	cfg_rx;
 static uint64_t glob_tstart;
 static uint64_t tdeliver_max;
 
+static int errors;
+
 /* encode one timed transmission (of a 1B payload) */
 struct timed_send {
 	char	data;
@@ -131,13 +135,15 @@ static void do_recv_one(int fdr, struct timed_send *ts)
 	fprintf(stderr, "payload:%c delay:%lld expected:%lld (us)\n",
 			rbuf[0], (long long)tstop, (long long)texpect);
 
-	if (rbuf[0] != ts->data)
-		error(1, 0, "payload mismatch. expected %c", ts->data);
+	if (rbuf[0] != ts->data) {
+		fprintf(stderr, "payload mismatch. expected %c\n", ts->data);
+		errors++;
+	}
 
 	if (llabs(tstop - texpect) > cfg_variance_us) {
 		fprintf(stderr, "exceeds variance (%d us)\n", cfg_variance_us);
 		if (!getenv("KSFT_MACHINE_SLOW"))
-			exit(1);
+			errors++;
 	}
 }
 
@@ -255,8 +261,12 @@ static void start_time_wait(void)
 		return;
 
 	now = gettime_ns(CLOCK_REALTIME);
-	if (cfg_start_time_ns < now)
+	if (cfg_start_time_ns < now) {
+		fprintf(stderr, "FAIL: start time already passed\n");
+		if (!getenv("KSFT_MACHINE_SLOW"))
+			errors++;
 		return;
+	}
 
 	err = usleep((cfg_start_time_ns - now) / 1000);
 	if (err)
@@ -513,5 +523,10 @@ int main(int argc, char **argv)
 	else
 		do_test_tx((void *)&cfg_src_addr, cfg_alen);
 
-	return 0;
+	if (errors) {
+		fprintf(stderr, "FAIL: %d errors\n", errors);
+		return KSFT_FAIL;
+	}
+
+	return KSFT_PASS;
 }
diff --git a/tools/testing/selftests/drivers/net/so_txtime.py b/tools/testing/selftests/drivers/net/so_txtime.py
new file mode 100755
index 000000000000..5b54ce76dff4
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/so_txtime.py
@@ -0,0 +1,96 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+"""Regression tests for the SO_TXTIME interface.
+
+Test delivery time in FQ and ETF qdiscs.
+"""
+
+import time
+
+from lib.py import ksft_exit, ksft_run, ksft_variants
+from lib.py import KsftNamedVariant, KsftSkipEx
+from lib.py import NetDrvEpEnv, bkg, cmd, defer, tc
+
+
+def test_so_txtime(cfg, clockid, ipver, args_tx, args_rx, expect_success):
+    """Main function. Run so_txtime as sender and receiver."""
+    bin_path = cfg.test_dir / "so_txtime"
+
+    tstart = time.time_ns() + 200_000_000
+
+    cmd_addr = f"-S {cfg.addr_v[ipver]} -D {cfg.remote_addr_v[ipver]}"
+    cmd_base = f"{bin_path} -{ipver} -c {clockid} -t {tstart} {cmd_addr}"
+    cmd_rx = f"{cmd_base} {args_rx} -r"
+    cmd_tx = f"{cmd_base} {args_tx}"
+
+    with bkg(cmd_rx, host=cfg.remote, fail=expect_success,
+             expect_fail=(not expect_success), exit_wait=True):
+        cmd(cmd_tx)
+
+
+def _qdisc_setup(ifname, qdisc, optargs=""):
+    """Replace root qdisc. Restore the original after the test.
+
+    If the original is mq, children will be of type default_qdisc.
+    """
+    orig = tc(f"qdisc show dev {ifname} root", json=True)[0].get("kind", None)
+    defer(tc, f"qdisc replace dev {ifname} root {orig}")
+    tc(f"qdisc replace dev {ifname} root {qdisc} {optargs}")
+
+
+def _test_variants_mono():
+    for ipver in ["4", "6"]:
+        for testcase in [
+            ["no_delay", "a,-1", "a,-1"],
+            ["zero_delay", "a,0", "a,0"],
+            ["one_pkt", "a,10", "a,10"],
+            ["in_order", "a,10,b,20", "a,10,b,20"],
+            ["reverse_order", "a,20,b,10", "b,20,a,20"],
+        ]:
+            name = f"v{ipver}_{testcase[0]}"
+            yield KsftNamedVariant(name, ipver, testcase[1], testcase[2])
+
+
+@ksft_variants(_test_variants_mono())
+def test_so_txtime_mono(cfg, ipver, args_tx, args_rx):
+    """Run all variants of monotonic (fq) tests."""
+    _qdisc_setup(cfg.ifname, "fq")
+    test_so_txtime(cfg, "mono", ipver, args_tx, args_rx, True)
+
+
+def _test_variants_etf():
+    for ipver in ["4", "6"]:
+        for testcase in [
+            ["no_delay", "a,-1", "a,-1", False],
+            ["zero_delay", "a,0", "a,0", False],
+            ["one_pkt", "a,10", "a,10", True],
+            ["in_order", "a,10,b,20", "a,10,b,20", True],
+            ["reverse_order", "a,20,b,10", "b,10,a,20", True],
+        ]:
+            name = f"v{ipver}_{testcase[0]}"
+            yield KsftNamedVariant(
+                name, ipver, testcase[1], testcase[2], testcase[3]
+            )
+
+
+@ksft_variants(_test_variants_etf())
+def test_so_txtime_etf(cfg, ipver, args_tx, args_rx, expect_fail):
+    """Run all variants of etf tests."""
+    try:
+        _qdisc_setup(cfg.ifname, "etf", "clockid CLOCK_TAI delta 400000")
+    except Exception as e:
+        raise KsftSkipEx("tc does not support qdisc etf. skipping") from e
+
+    test_so_txtime(cfg, "tai", ipver, args_tx, args_rx, expect_fail)
+
+
+def main() -> None:
+    """Boilerplate ksft main."""
+    with NetDrvEpEnv(__file__) as cfg:
+        ksft_run([test_so_txtime_mono, test_so_txtime_etf], args=(cfg,))
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore
index 97ad4d551d44..02ad4c99a2b4 100644
--- a/tools/testing/selftests/net/.gitignore
+++ b/tools/testing/selftests/net/.gitignore
@@ -40,7 +40,6 @@ skf_net_off
 socket
 so_incoming_cpu
 so_netns_cookie
-so_txtime
 so_rcv_listener
 stress_reuseport_listen
 tap
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index baa30287cf22..88c7573a8295 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -83,7 +83,6 @@ TEST_PROGS := \
 	rxtimestamp.sh \
 	sctp_vrf.sh \
 	skf_net_off.sh \
-	so_txtime.sh \
 	srv6_end_dt46_l3vpn_test.sh \
 	srv6_end_dt4_l3vpn_test.sh \
 	srv6_end_dt6_l3vpn_test.sh \
@@ -157,7 +156,6 @@ TEST_GEN_FILES := \
 	skf_net_off \
 	so_netns_cookie \
 	so_rcv_listener \
-	so_txtime \
 	socket \
 	stress_reuseport_listen \
 	tcp_fastopen_backup_key \
diff --git a/tools/testing/selftests/net/lib/py/__init__.py b/tools/testing/selftests/net/lib/py/__init__.py
index 7c81d86a7e97..64a8c1ed4950 100644
--- a/tools/testing/selftests/net/lib/py/__init__.py
+++ b/tools/testing/selftests/net/lib/py/__init__.py
@@ -14,7 +14,7 @@ from .netns import NetNS, NetNSEnter
 from .nsim import NetdevSim, NetdevSimDev
 from .utils import CmdExitFailure, fd_read_timeout, cmd, bkg, defer, \
     bpftool, ip, ethtool, bpftrace, rand_port, rand_ports, wait_port_listen, \
-    wait_file, tool
+    wait_file, tool, tc
 from .bpf import bpf_map_set, bpf_map_dump, bpf_prog_map_ids
 from .ynl import NlError, NlctrlFamily, YnlFamily, \
     EthtoolFamily, NetdevFamily, RtnlFamily, RtnlAddrFamily
@@ -29,7 +29,7 @@ __all__ = ["KSRC",
            "NetNS", "NetNSEnter",
            "CmdExitFailure", "fd_read_timeout", "cmd", "bkg", "defer",
            "bpftool", "ip", "ethtool", "bpftrace", "rand_port", "rand_ports",
-           "wait_port_listen", "wait_file", "tool",
+           "wait_port_listen", "wait_file", "tool", "tc",
            "bpf_map_set", "bpf_map_dump", "bpf_prog_map_ids",
            "NetdevSim", "NetdevSimDev",
            "NetshaperFamily", "DevlinkFamily", "PSPFamily", "NlError",
diff --git a/tools/testing/selftests/net/lib/py/utils.py b/tools/testing/selftests/net/lib/py/utils.py
index 6c44a3d2bbf7..be9408a77168 100644
--- a/tools/testing/selftests/net/lib/py/utils.py
+++ b/tools/testing/selftests/net/lib/py/utils.py
@@ -23,6 +23,10 @@ class CmdExitFailure(Exception):
         self.cmd = cmd_obj
 
 
+class CmdExitZeroFailure(CmdExitFailure):
+    """ Command succeeded (returned zero exit code), but expected failure. """
+
+
 def fd_read_timeout(fd, timeout):
     rlist, _, _ = select.select([fd], [], [], timeout)
     if rlist:
@@ -39,8 +43,9 @@ class cmd:
 
     Use bkg() instead to run a command in the background.
     """
-    def __init__(self, comm, shell=None, fail=True, ns=None, background=False,
-                 host=None, timeout=5, ksft_ready=None, ksft_wait=None):
+    def __init__(self, comm, shell=None, fail=True, expect_fail=False, ns=None,
+                 background=False, host=None, timeout=5, ksft_ready=None,
+                 ksft_wait=None):
         if ns:
             comm = f'ip netns exec {ns} ' + comm
 
@@ -88,7 +93,8 @@ class cmd:
                     self._process_terminate(terminate=terminate, timeout=1)
                     raise CmdInitFailure("Did not receive ready message", self)
         if not background:
-            self.process(terminate=False, fail=fail, timeout=timeout)
+            self.process(terminate=False, fail=fail, expect_fail=expect_fail,
+                         timeout=timeout)
 
     def _process_terminate(self, terminate, timeout):
         if terminate:
@@ -102,7 +108,7 @@ class cmd:
 
         return stdout, stderr
 
-    def process(self, terminate=True, fail=None, timeout=5):
+    def process(self, terminate=True, fail=None, expect_fail=False, timeout=5):
         if fail is None:
             fail = not terminate
 
@@ -111,10 +117,19 @@ class cmd:
 
         stdout, stderr = self._process_terminate(terminate=terminate,
                                                  timeout=timeout)
-        if self.proc.returncode != 0 and fail:
+
+        # Fail on unexpected test failure if fail.
+        # Fail on unexpected test success if expect_fail.
+        # Fail on negative returncode if either:
+        # Set by subprocess on crash or signal, this is never expected failure.
+        if (self.proc.returncode != 0 and fail or
+            (self.proc.returncode < 0 and expect_fail)):
             if len(stderr) > 0 and stderr[-1] == "\n":
                 stderr = stderr[:-1]
             raise CmdExitFailure("Command failed", self)
+        elif self.proc.returncode == 0 and expect_fail:
+            raise CmdExitZeroFailure("Command succeeded (expected fail)", self)
+
 
     def __repr__(self):
         def str_fmt(name, s):
@@ -157,14 +172,17 @@ class bkg(cmd):
 
         with bkg("my_binary", ksft_wait=5):
     """
-    def __init__(self, comm, shell=None, fail=None, ns=None, host=None,
-                 exit_wait=False, ksft_ready=None, ksft_wait=None):
+    def __init__(self, comm, shell=None, fail=None, expect_fail=None,
+                 ns=None, host=None, exit_wait=False, ksft_ready=None,
+                 ksft_wait=None):
         super().__init__(comm, background=True,
-                         shell=shell, fail=fail, ns=ns, host=host,
-                         ksft_ready=ksft_ready, ksft_wait=ksft_wait)
+                         shell=shell, fail=fail, expect_fail=expect_fail,
+                         ns=ns, host=host, ksft_ready=ksft_ready,
+                         ksft_wait=ksft_wait)
         self.terminate = not exit_wait and not ksft_wait
         self._exit_wait = exit_wait
         self.check_fail = fail
+        self.expect_fail = expect_fail
 
         if shell and self.terminate:
             print("# Warning: combining shell and terminate is risky!")
@@ -179,7 +197,8 @@ class bkg(cmd):
         # since forcing termination silences failures with fail=None
         if self.proc.poll() is None:
             terminate = terminate or (self._exit_wait and ex_type is not None)
-        return self.process(terminate=terminate, fail=self.check_fail)
+        return self.process(terminate=terminate, fail=self.check_fail,
+                            expect_fail=self.expect_fail)
 
 
 GLOBAL_DEFER_QUEUE = []
@@ -220,7 +239,10 @@ class defer:
 def tool(name, args, json=None, ns=None, host=None):
     cmd_str = name + ' '
     if json:
-        cmd_str += '--json '
+        if name == 'tc':
+            cmd_str += '-json '
+        else:
+            cmd_str += '--json '
     cmd_str += args
     cmd_obj = cmd(cmd_str, ns=ns, host=host)
     if json:
@@ -238,6 +260,13 @@ def ip(args, json=None, ns=None, host=None):
     return tool('ip', args, json=json, host=host)
 
 
+def tc(args, json=None, ns=None, host=None):
+    """ Helper to call tc with standard set of optional args. """
+    if ns:
+        args = f'-netns {ns} ' + args
+    return tool('tc', args, json=json, host=host)
+
+
 def ethtool(args, json=None, ns=None, host=None):
     return tool('ethtool', args, json=json, ns=ns, host=host)
 
diff --git a/tools/testing/selftests/net/so_txtime.sh b/tools/testing/selftests/net/so_txtime.sh
deleted file mode 100755
index 5e861ad32a42..000000000000
--- a/tools/testing/selftests/net/so_txtime.sh
+++ /dev/null
@@ -1,110 +0,0 @@
-#!/bin/bash
-# SPDX-License-Identifier: GPL-2.0
-#
-# Regression tests for the SO_TXTIME interface
-
-set -e
-
-readonly ksft_skip=4
-readonly DEV="veth0"
-readonly BIN="./so_txtime"
-
-readonly RAND="$(mktemp -u XXXXXX)"
-readonly NSPREFIX="ns-${RAND}"
-readonly NS1="${NSPREFIX}1"
-readonly NS2="${NSPREFIX}2"
-
-readonly SADDR4='192.168.1.1'
-readonly DADDR4='192.168.1.2'
-readonly SADDR6='fd::1'
-readonly DADDR6='fd::2'
-
-cleanup() {
-	ip netns del "${NS2}"
-	ip netns del "${NS1}"
-}
-
-trap cleanup EXIT
-
-# Create virtual ethernet pair between network namespaces
-ip netns add "${NS1}"
-ip netns add "${NS2}"
-
-ip link add "${DEV}" netns "${NS1}" type veth \
-  peer name "${DEV}" netns "${NS2}"
-
-# Bring the devices up
-ip -netns "${NS1}" link set "${DEV}" up
-ip -netns "${NS2}" link set "${DEV}" up
-
-# Set fixed MAC addresses on the devices
-ip -netns "${NS1}" link set dev "${DEV}" address 02:02:02:02:02:02
-ip -netns "${NS2}" link set dev "${DEV}" address 06:06:06:06:06:06
-
-# Add fixed IP addresses to the devices
-ip -netns "${NS1}" addr add 192.168.1.1/24 dev "${DEV}"
-ip -netns "${NS2}" addr add 192.168.1.2/24 dev "${DEV}"
-ip -netns "${NS1}" addr add       fd::1/64 dev "${DEV}" nodad
-ip -netns "${NS2}" addr add       fd::2/64 dev "${DEV}" nodad
-
-run_test() {
-	local readonly IP="$1"
-	local readonly CLOCK="$2"
-	local readonly TXARGS="$3"
-	local readonly RXARGS="$4"
-
-	if [[ "${IP}" == "4" ]]; then
-		local readonly SADDR="${SADDR4}"
-		local readonly DADDR="${DADDR4}"
-	elif [[ "${IP}" == "6" ]]; then
-		local readonly SADDR="${SADDR6}"
-		local readonly DADDR="${DADDR6}"
-	else
-		echo "Invalid IP version ${IP}"
-		exit 1
-	fi
-
-	local readonly START="$(date +%s%N --date="+ 0.1 seconds")"
-
-	ip netns exec "${NS2}" "${BIN}" -"${IP}" -c "${CLOCK}" -t "${START}" -S "${SADDR}" -D "${DADDR}" "${RXARGS}" -r &
-	ip netns exec "${NS1}" "${BIN}" -"${IP}" -c "${CLOCK}" -t "${START}" -S "${SADDR}" -D "${DADDR}" "${TXARGS}"
-	wait "$!"
-}
-
-do_test() {
-	run_test $@
-	[ $? -ne 0 ] && ret=1
-}
-
-do_fail_test() {
-	run_test $@
-	[ $? -eq 0 ] && ret=1
-}
-
-ip netns exec "${NS1}" tc qdisc add dev "${DEV}" root fq
-set +e
-ret=0
-do_test 4 mono a,-1 a,-1
-do_test 6 mono a,0 a,0
-do_test 6 mono a,10 a,10
-do_test 4 mono a,10,b,20 a,10,b,20
-do_test 6 mono a,20,b,10 b,20,a,20
-
-if ip netns exec "${NS1}" tc qdisc replace dev "${DEV}" root etf clockid CLOCK_TAI delta 400000; then
-	do_fail_test 4 tai a,-1 a,-1
-	do_fail_test 6 tai a,0 a,0
-	do_test 6 tai a,10 a,10
-	do_test 4 tai a,10,b,20 a,10,b,20
-	do_test 6 tai a,20,b,10 b,10,a,20
-else
-	echo "tc ($(tc -V)) does not support qdisc etf. skipping"
-	[ $ret -eq 0 ] && ret=$ksft_skip
-fi
-
-if [ $ret -eq 0 ]; then
-	echo OK. All tests passed
-elif [[ $ret -ne $ksft_skip && -n "$KSFT_MACHINE_SLOW" ]]; then
-	echo "Ignoring errors due to slow environment" 1>&2
-	ret=0
-fi
-exit $ret