diff options
| -rw-r--r-- | cloudinit/sources/DataSourceSmartOS.py | 2 | ||||
| -rw-r--r-- | tests/unittests/test_datasource/test_smartos.py | 67 |
2 files changed, 67 insertions, 2 deletions
diff --git a/cloudinit/sources/DataSourceSmartOS.py b/cloudinit/sources/DataSourceSmartOS.py index 0ef10035..4ea00eb1 100644 --- a/cloudinit/sources/DataSourceSmartOS.py +++ b/cloudinit/sources/DataSourceSmartOS.py @@ -23,6 +23,7 @@ import base64 import binascii import errno +import fcntl import json import os import random @@ -526,6 +527,7 @@ class JoyentMetadataSerialClient(JoyentMetadataClient): if not ser.isOpen(): raise SystemError("Unable to open %s" % self.device) self.fp = ser + fcntl.lockf(ser, fcntl.LOCK_EX) self._flush() self._negotiate() diff --git a/tests/unittests/test_datasource/test_smartos.py b/tests/unittests/test_datasource/test_smartos.py index b926263f..706e8eb8 100644 --- a/tests/unittests/test_datasource/test_smartos.py +++ b/tests/unittests/test_datasource/test_smartos.py @@ -16,23 +16,27 @@ from __future__ import print_function from binascii import crc32 import json +import multiprocessing import os import os.path import re import shutil +import signal import stat import tempfile +import unittest2 import uuid from cloudinit import serial from cloudinit.sources import DataSourceSmartOS from cloudinit.sources.DataSourceSmartOS import ( - convert_smartos_network_data as convert_net) + convert_smartos_network_data as convert_net, + SMARTOS_ENV_KVM, SERIAL_DEVICE, get_smartos_environ) import six from cloudinit import helpers as c_helpers -from cloudinit.util import b64e +from cloudinit.util import (b64e, subp) from cloudinit.tests.helpers import mock, FilesystemMockingTestCase, TestCase @@ -1023,4 +1027,63 @@ class TestNetworkConversion(TestCase): found = convert_net(SDC_NICS_SINGLE_GATEWAY) self.assertEqual(expected, found) + +@unittest2.skipUnless(get_smartos_environ() == SMARTOS_ENV_KVM, + "Only supported on KVM and bhyve guests under SmartOS") +@unittest2.skipUnless(os.access(SERIAL_DEVICE, os.W_OK), + "Requires write access to " + SERIAL_DEVICE) +class TestSerialConcurrency(TestCase): + """ + This class tests locking on an actual serial port, and as such can only + be run in a kvm or bhyve guest running on a SmartOS host. A test run on + a metadata socket will not be valid because a metadata socket ensures + there is only one session over a connection. In contrast, in the + absence of proper locking multiple processes opening the same serial + port can corrupt each others' exchanges with the metadata server. + """ + def setUp(self): + self.mdata_proc = multiprocessing.Process(target=self.start_mdata_loop) + self.mdata_proc.start() + super(TestSerialConcurrency, self).setUp() + + def tearDown(self): + # os.kill() rather than mdata_proc.terminate() to avoid console spam. + os.kill(self.mdata_proc.pid, signal.SIGKILL) + self.mdata_proc.join() + super(TestSerialConcurrency, self).tearDown() + + def start_mdata_loop(self): + """ + The mdata-get command is repeatedly run in a separate process so + that it may try to race with metadata operations performed in the + main test process. Use of mdata-get is better than two processes + using the protocol implementation in DataSourceSmartOS because we + are testing to be sure that cloud-init and mdata-get respect each + others locks. + """ + rcs = list(range(0, 256)) + while True: + subp(['mdata-get', 'sdc:routes'], rcs=rcs) + + def test_all_keys(self): + self.assertIsNotNone(self.mdata_proc.pid) + ds = DataSourceSmartOS + keys = [tup[0] for tup in ds.SMARTOS_ATTRIB_MAP.values()] + keys.extend(ds.SMARTOS_ATTRIB_JSON.values()) + + client = ds.jmc_client_factory() + self.assertIsNotNone(client) + + # The behavior that we are testing for was observed mdata-get running + # 10 times at roughly the same time as cloud-init fetched each key + # once. cloud-init would regularly see failures before making it + # through all keys once. + for _ in range(0, 3): + for key in keys: + # We don't care about the return value, just that it doesn't + # thrown any exceptions. + client.get(key) + + self.assertIsNone(self.mdata_proc.exitcode) + # vi: ts=4 expandtab |