linux/tools/testing/selftests/net/devlink_port_split.py
Po-Hsu Lin 24994513ad selftests: net: devlink_port_split.py: skip test if no suitable device available
The `devlink -j port show` command output may not contain the "flavour"
key, an example from Ubuntu 22.10 s390x LPAR(5.19.0-37-generic), with
mlx4 driver and iproute2-5.15.0:
  {"port":{"pci/0001:00:00.0/1":{"type":"eth","netdev":"ens301"},
           "pci/0001:00:00.0/2":{"type":"eth","netdev":"ens301d1"},
           "pci/0002:00:00.0/1":{"type":"eth","netdev":"ens317"},
           "pci/0002:00:00.0/2":{"type":"eth","netdev":"ens317d1"}}}

This will cause a KeyError exception.

Create a validate_devlink_output() to check for this "flavour" from
devlink command output to avoid this KeyError exception. Also let
it handle the check for `devlink -j dev show` output in main().

Apart from this, if the test was not started because the max lanes of
the designated device is 0. The script will still return 0 and thus
causing a false-negative test result.

Use a found_max_lanes flag to determine if these tests were skipped
due to this reason and return KSFT_SKIP to make it more clear.

Link: https://bugs.launchpad.net/bugs/1937133
Fixes: f3348a82e7 ("selftests: net: Add port split test")
Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Link: https://lore.kernel.org/r/20230315165353.229590-1-po-hsu.lin@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-16 17:38:05 -07:00

310 lines
8.2 KiB
Python
Executable File

#!/usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0
from subprocess import PIPE, Popen
import json
import time
import argparse
import collections
import sys
#
# Test port split configuration using devlink-port lanes attribute.
# The test is skipped in case the attribute is not available.
#
# First, check that all the ports with 1 lane fail to split.
# Second, check that all the ports with more than 1 lane can be split
# to all valid configurations (e.g., split to 2, split to 4 etc.)
#
# Kselftest framework requirement - SKIP code is 4
KSFT_SKIP=4
Port = collections.namedtuple('Port', 'bus_info name')
def run_command(cmd, should_fail=False):
"""
Run a command in subprocess.
Return: Tuple of (stdout, stderr).
"""
p = Popen(cmd, stdout=PIPE, stderr=PIPE, shell=True)
stdout, stderr = p.communicate()
stdout, stderr = stdout.decode(), stderr.decode()
if stderr != "" and not should_fail:
print("Error sending command: %s" % cmd)
print(stdout)
print(stderr)
return stdout, stderr
class devlink_ports(object):
"""
Class that holds information on the devlink ports, required to the tests;
if_names: A list of interfaces in the devlink ports.
"""
def get_if_names(dev):
"""
Get a list of physical devlink ports.
Return: Array of tuples (bus_info/port, if_name).
"""
arr = []
cmd = "devlink -j port show"
stdout, stderr = run_command(cmd)
assert stderr == ""
ports = json.loads(stdout)['port']
validate_devlink_output(ports, 'flavour')
for port in ports:
if dev in port:
if ports[port]['flavour'] == 'physical':
arr.append(Port(bus_info=port, name=ports[port]['netdev']))
return arr
def __init__(self, dev):
self.if_names = devlink_ports.get_if_names(dev)
def get_max_lanes(port):
"""
Get the $port's maximum number of lanes.
Return: number of lanes, e.g. 1, 2, 4 and 8.
"""
cmd = "devlink -j port show %s" % port
stdout, stderr = run_command(cmd)
assert stderr == ""
values = list(json.loads(stdout)['port'].values())[0]
if 'lanes' in values:
lanes = values['lanes']
else:
lanes = 0
return lanes
def get_split_ability(port):
"""
Get the $port split ability.
Return: split ability, true or false.
"""
cmd = "devlink -j port show %s" % port.name
stdout, stderr = run_command(cmd)
assert stderr == ""
values = list(json.loads(stdout)['port'].values())[0]
return values['splittable']
def split(k, port, should_fail=False):
"""
Split $port into $k ports.
If should_fail == True, the split should fail. Otherwise, should pass.
Return: Array of sub ports after splitting.
If the $port wasn't split, the array will be empty.
"""
cmd = "devlink port split %s count %s" % (port.bus_info, k)
stdout, stderr = run_command(cmd, should_fail=should_fail)
if should_fail:
if not test(stderr != "", "%s is unsplittable" % port.name):
print("split an unsplittable port %s" % port.name)
return create_split_group(port, k)
else:
if stderr == "":
return create_split_group(port, k)
print("didn't split a splittable port %s" % port.name)
return []
def unsplit(port):
"""
Unsplit $port.
"""
cmd = "devlink port unsplit %s" % port
stdout, stderr = run_command(cmd)
test(stderr == "", "Unsplit port %s" % port)
def exists(port, dev):
"""
Check if $port exists in the devlink ports.
Return: True is so, False otherwise.
"""
return any(dev_port.name == port
for dev_port in devlink_ports.get_if_names(dev))
def exists_and_lanes(ports, lanes, dev):
"""
Check if every port in the list $ports exists in the devlink ports and has
$lanes number of lanes after splitting.
Return: True if both are True, False otherwise.
"""
for port in ports:
max_lanes = get_max_lanes(port)
if not exists(port, dev):
print("port %s doesn't exist in devlink ports" % port)
return False
if max_lanes != lanes:
print("port %s has %d lanes, but %s were expected"
% (port, lanes, max_lanes))
return False
return True
def test(cond, msg):
"""
Check $cond and print a message accordingly.
Return: True is pass, False otherwise.
"""
if cond:
print("TEST: %-60s [ OK ]" % msg)
else:
print("TEST: %-60s [FAIL]" % msg)
return cond
def create_split_group(port, k):
"""
Create the split group for $port.
Return: Array with $k elements, which are the split port group.
"""
return list(port.name + "s" + str(i) for i in range(k))
def split_unsplittable_port(port, k):
"""
Test that splitting of unsplittable port fails.
"""
# split to max
new_split_group = split(k, port, should_fail=True)
if new_split_group != []:
unsplit(port.bus_info)
def split_splittable_port(port, k, lanes, dev):
"""
Test that splitting of splittable port passes correctly.
"""
new_split_group = split(k, port)
# Once the split command ends, it takes some time to the sub ifaces'
# to get their names. Use udevadm to continue only when all current udev
# events are handled.
cmd = "udevadm settle"
stdout, stderr = run_command(cmd)
assert stderr == ""
if new_split_group != []:
test(exists_and_lanes(new_split_group, lanes/k, dev),
"split port %s into %s" % (port.name, k))
unsplit(port.bus_info)
def validate_devlink_output(devlink_data, target_property=None):
"""
Determine if test should be skipped by checking:
1. devlink_data contains values
2. The target_property exist in devlink_data
"""
skip_reason = None
if any(devlink_data.values()):
if target_property:
skip_reason = "{} not found in devlink output, test skipped".format(target_property)
for key in devlink_data:
if target_property in devlink_data[key]:
skip_reason = None
else:
skip_reason = 'devlink output is empty, test skipped'
if skip_reason:
print(skip_reason)
sys.exit(KSFT_SKIP)
def make_parser():
parser = argparse.ArgumentParser(description='A test for port splitting.')
parser.add_argument('--dev',
help='The devlink handle of the device under test. ' +
'The default is the first registered devlink ' +
'handle.')
return parser
def main(cmdline=None):
parser = make_parser()
args = parser.parse_args(cmdline)
dev = args.dev
if not dev:
cmd = "devlink -j dev show"
stdout, stderr = run_command(cmd)
assert stderr == ""
validate_devlink_output(json.loads(stdout))
devs = json.loads(stdout)['dev']
dev = list(devs.keys())[0]
cmd = "devlink dev show %s" % dev
stdout, stderr = run_command(cmd)
if stderr != "":
print("devlink device %s can not be found" % dev)
sys.exit(1)
ports = devlink_ports(dev)
found_max_lanes = False
for port in ports.if_names:
max_lanes = get_max_lanes(port.name)
# If max lanes is 0, do not test port splitting at all
if max_lanes == 0:
continue
# If 1 lane, shouldn't be able to split
elif max_lanes == 1:
test(not get_split_ability(port),
"%s should not be able to split" % port.name)
split_unsplittable_port(port, max_lanes)
# Else, splitting should pass and all the split ports should exist.
else:
lane = max_lanes
test(get_split_ability(port),
"%s should be able to split" % port.name)
while lane > 1:
split_splittable_port(port, lane, max_lanes, dev)
lane //= 2
found_max_lanes = True
if not found_max_lanes:
print(f"Test not started, no port of device {dev} reports max_lanes")
sys.exit(KSFT_SKIP)
if __name__ == "__main__":
main()