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      1 # Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
      2 # Use of this source code is governed by a BSD-style license that can be
      3 # found in the LICENSE file.
      4 
      5 import datetime
      6 import logging
      7 import time
      8 import warnings
      9 
     10 import common
     11 
     12 from autotest_lib.client.common_lib import base_job
     13 from autotest_lib.client.common_lib import error
     14 from autotest_lib.client.common_lib import priorities
     15 from autotest_lib.client.common_lib import time_utils
     16 from autotest_lib.client.common_lib import utils
     17 from autotest_lib.client.common_lib.cros import dev_server
     18 from autotest_lib.server.cros import provision
     19 from autotest_lib.server.cros.dynamic_suite import constants
     20 from autotest_lib.server.cros.dynamic_suite import frontend_wrappers
     21 from autotest_lib.server.cros.dynamic_suite.suite import ProvisionSuite
     22 from autotest_lib.server.cros.dynamic_suite.suite import Suite
     23 from autotest_lib.tko import utils as tko_utils
     24 
     25 
     26 """CrOS dynamic test suite generation and execution module.
     27 
     28 This module implements runtime-generated test suites for CrOS.
     29 Design doc: http://goto.google.com/suitesv2
     30 
     31 Individual tests can declare themselves as a part of one or more
     32 suites, and the code here enables control files to be written
     33 that can refer to these "dynamic suites" by name.  We also provide
     34 support for reimaging devices with a given build and running a
     35 dynamic suite across all reimaged devices.
     36 
     37 The public API for defining a suite includes one method: reimage_and_run().
     38 A suite control file can be written by importing this module and making
     39 an appropriate call to this single method.  In normal usage, this control
     40 file will be run in a 'hostless' server-side autotest job, scheduling
     41 sub-jobs to do the needed reimaging and test running.
     42 
     43 Example control file:
     44 
     45 import common
     46 from autotest_lib.server.cros import provision
     47 from autotest_lib.server.cros.dynamic_suite import dynamic_suite
     48 
     49 dynamic_suite.reimage_and_run(
     50     builds={provision.CROS_VERSION_PREFIX: build}, board=board, name='bvt',
     51     job=job, pool=pool, check_hosts=check_hosts, add_experimental=True,
     52     devserver_url=devserver_url)
     53 
     54 This will -- at runtime -- find all control files that contain "bvt" in their
     55 "SUITE=" clause, schedule jobs to reimage devices in the
     56 specified pool of the specified board with the specified build and, upon
     57 completion of those jobs, schedule and wait for jobs that run all the tests it
     58 discovered.
     59 
     60 Suites can be run by using the atest command-line tool:
     61   atest suite create -b <board> -i <build/name> <suite>
     62 e.g.
     63   atest suite create -b x86-mario -i x86-mario/R20-2203.0.0 bvt
     64 
     65 -------------------------------------------------------------------------
     66 Implementation details
     67 
     68 A Suite instance represents a single test suite, defined by some predicate
     69 run over all known control files.  The simplest example is creating a Suite
     70 by 'name'.
     71 
     72 create_suite_job() takes the parameters needed to define a suite run (board,
     73 build to test, machine pool, and which suite to run), ensures important
     74 preconditions are met, finds the appropraite suite control file, and then
     75 schedules the hostless job that will do the rest of the work.
     76 
     77 Note that we have more than one Dev server in our test lab architecture.
     78 We currently load balance per-build being tested, so one and only one dev
     79 server is used by any given run through the reimaging/testing flow.
     80 
     81 - create_suite_job()
     82 The primary role of create_suite_job() is to ensure that the required
     83 artifacts for the build to be tested are staged on the dev server.  This
     84 includes payloads required to autoupdate machines to the desired build, as
     85 well as the autotest control files appropriate for that build.  Then, the
     86 RPC pulls the control file for the suite to be run from the dev server and
     87 uses it to create the suite job with the autotest frontend.
     88 
     89      +----------------+
     90      | Google Storage |                                Client
     91      +----------------+                                   |
     92                | ^                                        | create_suite_job()
     93  payloads/     | |                                        |
     94  control files | | request                                |
     95                V |                                        V
     96        +-------------+   download request    +--------------------------+
     97        |             |<----------------------|                          |
     98        | Dev Server  |                       | Autotest Frontend (AFE)  |
     99        |             |---------------------->|                          |
    100        +-------------+  suite control file   +--------------------------+
    101                                                           |
    102                                                           V
    103                                                       Suite Job (hostless)
    104 
    105 - Reimage and Run
    106 The overall process is to schedule all the tests, and then wait for the tests
    107 to complete.
    108 
    109 - The Reimaging Process
    110 
    111 As an artifact of an old implementation, the number of machines to use
    112 is called the 'sharding_factor', and the default is defined in the [CROS]
    113 section of global_config.ini.
    114 
    115 There used to be a 'num' parameter to control the maximum number of
    116 machines, but it does not do anything any more.
    117 
    118 A test control file can specify a list of DEPENDENCIES, which are really just
    119 the set of labels a host needs to have in order for that test to be scheduled
    120 on it.  In the case of a dynamic_suite, many tests in the suite may have
    121 DEPENDENCIES specified.  All tests are scheduled with the DEPENDENCIES that
    122 they specify, along with any suite dependencies that were specified, and the
    123 scheduler will find and provision a host capable of running the test.
    124 
    125 - Scheduling Suites
    126 A Suite instance uses the labels specified in the suite dependencies to
    127 schedule tests across all the hosts in the pool.  It then waits for all these
    128 jobs.  As an optimization, the Dev server stages the payloads necessary to
    129 run a suite in the background _after_ it has completed all the things
    130 necessary for reimaging.  Before running a suite, reimage_and_run() calls out
    131 to the Dev server and blocks until it's completed staging all build artifacts
    132 needed to run test suites.
    133 
    134 Step by step:
    135 0) At instantiation time, find all appropriate control files for this suite
    136    that were included in the build to be tested.  To do this, we consult the
    137    Dev Server, where all these control files are staged.
    138 
    139           +------------+    control files?     +--------------------------+
    140           |            |<----------------------|                          |
    141           | Dev Server |                       | Autotest Frontend (AFE)  |
    142           |            |---------------------->|       [Suite Job]        |
    143           +------------+    control files!     +--------------------------+
    144 
    145 1) Now that the Suite instance exists, it schedules jobs for every control
    146    file it deemed appropriate, to be run on the hosts that were labeled
    147    by the provisioning.  We stuff keyvals into these jobs, indicating what
    148    build they were testing and which suite they were for.
    149 
    150    +--------------------------+ Job for VersLabel       +--------+
    151    |                          |------------------------>| Host 1 | VersLabel
    152    | Autotest Frontend (AFE)  |            +--------+   +--------+
    153    |       [Suite Job]        |----------->| Host 2 |
    154    +--------------------------+ Job for    +--------+
    155        |                ^       VersLabel        VersLabel
    156        |                |
    157        +----------------+
    158         One job per test
    159         {'build': build/name,
    160          'suite': suite_name}
    161 
    162 2) Now that all jobs are scheduled, they'll be doled out as labeled hosts
    163    finish their assigned work and become available again.
    164 
    165 - Waiting on Suites
    166 0) As we clean up each test job, we check to see if any crashes occurred.  If
    167    they did, we look at the 'build' keyval in the job to see which build's debug
    168    symbols we'll need to symbolicate the crash dump we just found.
    169 
    170 1) Using this info, we tell a special Crash Server to stage the required debug
    171    symbols. Once that's done, we ask the Crash Server to use those symbols to
    172    symbolicate the crash dump in question.
    173 
    174      +----------------+
    175      | Google Storage |
    176      +----------------+
    177           |     ^
    178  symbols! |     | symbols?
    179           V     |
    180       +------------+  stage symbols for build  +--------------------------+
    181       |            |<--------------------------|                          |
    182       |   Crash    |                           |                          |
    183       |   Server   |   dump to symbolicate     | Autotest Frontend (AFE)  |
    184       |            |<--------------------------|       [Suite Job]        |
    185       |            |-------------------------->|                          |
    186       +------------+    symbolicated dump      +--------------------------+
    187 
    188 2) As jobs finish, we record their success or failure in the status of the suite
    189    job.  We also record a 'job keyval' in the suite job for each test, noting
    190    the job ID and job owner.  This can be used to refer to test logs later.
    191 3) Once all jobs are complete, status is recorded for the suite job, and the
    192    job_repo_url host attribute is removed from all hosts used by the suite.
    193 
    194 """
    195 
    196 
    197 # Relevant CrosDynamicSuiteExceptions are defined in client/common_lib/error.py.
    198 
    199 class _SuiteSpec(object):
    200     """This class contains the info that defines a suite run."""
    201 
    202     _REQUIRED_KEYWORDS = {
    203             'board': str,
    204             'builds': dict,
    205             'name': str,
    206             'job': base_job.base_job,
    207             'devserver_url': str,
    208     }
    209 
    210     _VERSION_PREFIXES = frozenset((
    211             provision.CROS_VERSION_PREFIX,
    212             provision.CROS_ANDROID_VERSION_PREFIX,
    213     ))
    214 
    215     def __init__(
    216             self,
    217             builds=None,
    218             board=None,
    219             name=None,
    220             job=None,
    221             devserver_url=None,
    222             pool=None,
    223             check_hosts=True,
    224             add_experimental=True,
    225             file_bugs=False,
    226             max_runtime_mins=24*60,
    227             timeout_mins=24*60,
    228             suite_dependencies=None,
    229             bug_template=None,
    230             priority=priorities.Priority.DEFAULT,
    231             predicate=None,
    232             wait_for_results=True,
    233             job_retry=False,
    234             max_retries=None,
    235             offload_failures_only=False,
    236             test_source_build=None,
    237             run_prod_code=False,
    238             delay_minutes=0,
    239             job_keyvals=None,
    240             test_args=None,
    241             child_dependencies=(),
    242             **dargs):
    243         """
    244         Vets arguments for reimage_and_run() and populates self with supplied
    245         values.
    246 
    247         Currently required args:
    248         @param builds: the builds to install e.g.
    249                        {'cros-version:': 'x86-alex-release/R18-1655.0.0',
    250                         'fwrw-version:': 'x86-alex-firmware/R36-5771.50.0'}
    251         @param board: which kind of devices to reimage.
    252         @param name: a value of the SUITE control file variable to search for.
    253         @param job: an instance of client.common_lib.base_job representing the
    254                     currently running suite job.
    255         @param devserver_url: url to the selected devserver.
    256 
    257         Currently supported optional args:
    258         @param pool: the pool of machines to use for scheduling purposes.
    259         @param check_hosts: require appropriate hosts to be available now.
    260         @param add_experimental: schedule experimental tests as well, or not.
    261         @param file_bugs: File bugs when tests in this suite fail.
    262         @param max_runtime_mins: Max runtime in mins for each of the sub-jobs
    263                                  this suite will run.
    264         @param timeout_mins: Max lifetime in minutes for each of the sub-jobs
    265                              that this suite runs.
    266         @param suite_dependencies: A list of strings of suite level
    267                                    dependencies, which act just like test
    268                                    dependencies and are appended to each test's
    269                                    set of dependencies at job creation time.
    270                                    A string of comma seperated labels is
    271                                    accepted for backwards compatibility.
    272         @param bug_template: A template dictionary specifying the default bug
    273                              filing options for failures in this suite.
    274         @param priority: Integer priority level.  Higher is more important.
    275         @param predicate: Optional argument. If present, should be a function
    276                           mapping ControlData objects to True if they should be
    277                           included in suite. If argument is absent, suite
    278                           behavior will default to creating a suite of based
    279                           on the SUITE field of control files.
    280         @param wait_for_results: Set to False to run the suite job without
    281                                  waiting for test jobs to finish.
    282         @param job_retry: Set to True to enable job-level retry.
    283         @param max_retries: Maximum retry limit at suite level if not None.
    284                             Regardless how many times each individual test
    285                             has been retried, the total number of retries
    286                             happening in the suite can't exceed max_retries.
    287         @param offload_failures_only: Only enable gs_offloading for failed
    288                                       jobs.
    289         @param test_source_build: Build that contains the server-side test code,
    290                 e.g., it can be the value of builds['cros-version:'] or
    291                 builds['fw-version:']. None uses the server-side test code from
    292                 builds['cros-version:'].
    293         @param run_prod_code: If true, the suite will run the test code that
    294                               lives in prod aka the test code currently on the
    295                               lab servers.
    296         @param delay_minutes: Delay the creation of test jobs for a given number
    297                               of minutes.
    298         @param job_keyvals: General job keyvals to be inserted into keyval file
    299         @param test_args: A dict of args passed all the way to each individual
    300                           test that will be actually ran.
    301         @param child_dependencies: (optional) list of dependency strings
    302                 to be added as dependencies to child jobs.
    303         @param **dargs: these arguments will be ignored.  This allows us to
    304                         deprecate and remove arguments in ToT while not
    305                         breaking branch builds.
    306         """
    307         self._check_init_params(
    308                 board=board,
    309                 builds=builds,
    310                 name=name,
    311                 job=job,
    312                 devserver_url=devserver_url)
    313 
    314         self.board = 'board:%s' % board
    315         self.builds = builds
    316         self.name = name
    317         self.job = job
    318         self.pool = ('pool:%s' % pool) if pool else pool
    319         self.check_hosts = check_hosts
    320         self.add_experimental = add_experimental
    321         self.file_bugs = file_bugs
    322         self.dependencies = {'': []}
    323         self.max_runtime_mins = max_runtime_mins
    324         self.timeout_mins = timeout_mins
    325         self.bug_template = {} if bug_template is None else bug_template
    326         self.priority = priority
    327         self.wait_for_results = wait_for_results
    328         self.job_retry = job_retry
    329         self.max_retries = max_retries
    330         self.offload_failures_only = offload_failures_only
    331         self.run_prod_code = run_prod_code
    332         self.delay_minutes = delay_minutes
    333         self.job_keyvals = job_keyvals
    334         self.test_args = test_args
    335         self.child_dependencies = child_dependencies
    336 
    337         self._init_predicate(predicate)
    338         self._init_suite_dependencies(suite_dependencies)
    339         self._init_devserver(devserver_url)
    340         self._init_test_source_build(test_source_build)
    341         self._translate_builds()
    342         self._add_builds_to_suite_deps()
    343 
    344         for key, value in dargs.iteritems():
    345             warnings.warn('Ignored key %r was passed to suite with value %r'
    346                           % (key, value))
    347 
    348     def _check_init_params(self, **kwargs):
    349         for key, expected_type in self._REQUIRED_KEYWORDS.iteritems():
    350             value = kwargs.get(key)
    351             # TODO(ayatane): `not value` includes both the cases where value is
    352             # None and where value is the correct type, but empty (e.g., empty
    353             # dict).  It looks like this is NOT the intended behavior, but I'm
    354             # hesitant to remove it in case something is actually relying on
    355             # this behavior.
    356             if not value or not isinstance(value, expected_type):
    357                 raise error.SuiteArgumentException(
    358                         'reimage_and_run() needs %s=<%r>'
    359                         % (key, expected_type))
    360 
    361     def _init_predicate(self, predicate):
    362         """Initialize predicate attribute."""
    363         if predicate is None:
    364             self.predicate = Suite.name_in_tag_predicate(self.name)
    365         else:
    366             self.predicate = predicate
    367 
    368 
    369     def _init_suite_dependencies(self, suite_dependencies):
    370         """Initialize suite dependencies attribute."""
    371         if suite_dependencies is None:
    372             self.suite_dependencies = []
    373         elif isinstance(suite_dependencies, str):
    374             self.suite_dependencies = [dep.strip(' ') for dep
    375                                        in suite_dependencies.split(',')]
    376         else:
    377             self.suite_dependencies = suite_dependencies
    378 
    379     def _init_devserver(self, devserver_url):
    380         """Initialize devserver attribute."""
    381         self.devserver = dev_server.ImageServer(devserver_url)
    382 
    383     def _init_test_source_build(self, test_source_build):
    384         """Initialize test_source_build attribute."""
    385         if test_source_build:
    386             test_source_build = self.devserver.translate(test_source_build)
    387 
    388         self.test_source_build = Suite.get_test_source_build(
    389                 self.builds, test_source_build=test_source_build)
    390 
    391     def _translate_builds(self):
    392         """Translate build names if they are in LATEST format."""
    393         for prefix in self._VERSION_PREFIXES:
    394             if prefix in self.builds:
    395                 translated_build = self.devserver.translate(
    396                         self.builds[prefix])
    397                 self.builds[prefix] = translated_build
    398 
    399     def _add_builds_to_suite_deps(self):
    400         """Add builds to suite_dependencies.
    401 
    402         To support provision both CrOS and firmware, option builds are added to
    403         _SuiteSpec, e.g.,
    404 
    405         builds = {'cros-version:': 'x86-alex-release/R18-1655.0.0',
    406                   'fwrw-version:': 'x86-alex-firmware/R36-5771.50.0'}
    407 
    408         version_prefix+build should make it into each test as a DEPENDENCY.
    409         The easiest way to do this is to tack it onto the suite_dependencies.
    410         """
    411         self.suite_dependencies.extend(
    412                 provision.join(version_prefix, build)
    413                 for version_prefix, build in self.builds.iteritems()
    414         )
    415 
    416 
    417 class _ProvisionSuiteSpec(_SuiteSpec):
    418 
    419     def __init__(self, num_required, **kwargs):
    420         self.num_required = num_required
    421         super(_ProvisionSuiteSpec, self).__init__(**kwargs)
    422 
    423 
    424 def run_provision_suite(**dargs):
    425     """
    426     Run a provision suite.
    427 
    428     Will re-image a number of devices (of the specified board) with the
    429     provided builds by scheduling dummy_Pass.
    430 
    431     @param job: an instance of client.common_lib.base_job representing the
    432                 currently running suite job.
    433 
    434     @raises AsynchronousBuildFailure: if there was an issue finishing staging
    435                                       from the devserver.
    436     @raises MalformedDependenciesException: if the dependency_info file for
    437                                             the required build fails to parse.
    438     """
    439     spec = _ProvisionSuiteSpec(**dargs)
    440 
    441     afe = frontend_wrappers.RetryingAFE(timeout_min=30, delay_sec=10,
    442                                         user=spec.job.user, debug=False)
    443     tko = frontend_wrappers.RetryingTKO(timeout_min=30, delay_sec=10,
    444                                         user=spec.job.user, debug=False)
    445 
    446     try:
    447         my_job_id = int(tko_utils.get_afe_job_id(spec.job.tag))
    448         logging.debug('Determined own job id: %d', my_job_id)
    449     except (TypeError, ValueError):
    450         my_job_id = None
    451         logging.warning('Could not determine own job id.')
    452 
    453     suite = ProvisionSuite(
    454             tag=spec.name,
    455             builds=spec.builds,
    456             board=spec.board,
    457             devserver=spec.devserver,
    458             num_required=spec.num_required,
    459             afe=afe,
    460             tko=tko,
    461             pool=spec.pool,
    462             results_dir=spec.job.resultdir,
    463             max_runtime_mins=spec.max_runtime_mins,
    464             timeout_mins=spec.timeout_mins,
    465             file_bugs=spec.file_bugs,
    466             suite_job_id=my_job_id,
    467             extra_deps=spec.suite_dependencies,
    468             priority=spec.priority,
    469             wait_for_results=spec.wait_for_results,
    470             job_retry=spec.job_retry,
    471             max_retries=spec.max_retries,
    472             offload_failures_only=spec.offload_failures_only,
    473             test_source_build=spec.test_source_build,
    474             run_prod_code=spec.run_prod_code,
    475             job_keyvals=spec.job_keyvals,
    476             test_args=spec.test_args,
    477             child_dependencies=spec.child_dependencies,
    478     )
    479 
    480     _run_suite_with_spec(suite, spec)
    481 
    482     logging.debug('Returning from dynamic_suite.run_provision_suite')
    483 
    484 
    485 def reimage_and_run(**dargs):
    486     """
    487     Backward-compatible API for dynamic_suite.
    488 
    489     Will re-image a number of devices (of the specified board) with the
    490     provided builds, and then run the indicated test suite on them.
    491     Guaranteed to be compatible with any build from stable to dev.
    492 
    493     @param dargs: Dictionary containing the arguments passed to _SuiteSpec().
    494     @raises AsynchronousBuildFailure: if there was an issue finishing staging
    495                                       from the devserver.
    496     @raises MalformedDependenciesException: if the dependency_info file for
    497                                             the required build fails to parse.
    498     """
    499     suite_spec = _SuiteSpec(**dargs)
    500 
    501     afe = frontend_wrappers.RetryingAFE(timeout_min=30, delay_sec=10,
    502                                         user=suite_spec.job.user, debug=False)
    503     tko = frontend_wrappers.RetryingTKO(timeout_min=30, delay_sec=10,
    504                                         user=suite_spec.job.user, debug=False)
    505 
    506     try:
    507         my_job_id = int(tko_utils.get_afe_job_id(dargs['job'].tag))
    508         logging.debug('Determined own job id: %d', my_job_id)
    509     except (TypeError, ValueError):
    510         my_job_id = None
    511         logging.warning('Could not determine own job id.')
    512 
    513     _perform_reimage_and_run(suite_spec, afe, tko, suite_job_id=my_job_id)
    514 
    515     logging.debug('Returning from dynamic_suite.reimage_and_run.')
    516 
    517 
    518 def _perform_reimage_and_run(spec, afe, tko, suite_job_id=None):
    519     """
    520     Do the work of reimaging hosts and running tests.
    521 
    522     @param spec: a populated _SuiteSpec object.
    523     @param afe: an instance of AFE as defined in server/frontend.py.
    524     @param tko: an instance of TKO as defined in server/frontend.py.
    525     @param suite_job_id: Job id that will act as parent id to all sub jobs.
    526                          Default: None
    527     """
    528     # We can't create the suite until the devserver has finished downloading
    529     # control_files and test_suites packages so that we can get the control
    530     # files to schedule.
    531     if not spec.run_prod_code:
    532         _stage_artifacts_for_build(spec.devserver, spec.test_source_build)
    533     suite = Suite.create_from_predicates(
    534             predicates=[spec.predicate],
    535             name=spec.name,
    536             builds=spec.builds,
    537             board=spec.board,
    538             devserver=spec.devserver,
    539             afe=afe,
    540             tko=tko,
    541             pool=spec.pool,
    542             results_dir=spec.job.resultdir,
    543             max_runtime_mins=spec.max_runtime_mins,
    544             timeout_mins=spec.timeout_mins,
    545             file_bugs=spec.file_bugs,
    546             suite_job_id=suite_job_id,
    547             extra_deps=spec.suite_dependencies,
    548             priority=spec.priority,
    549             wait_for_results=spec.wait_for_results,
    550             job_retry=spec.job_retry,
    551             max_retries=spec.max_retries,
    552             offload_failures_only=spec.offload_failures_only,
    553             test_source_build=spec.test_source_build,
    554             run_prod_code=spec.run_prod_code,
    555             job_keyvals=spec.job_keyvals,
    556             test_args=spec.test_args,
    557             child_dependencies=spec.child_dependencies,
    558     )
    559     _run_suite_with_spec(suite, spec)
    560 
    561 
    562 def _run_suite_with_spec(suite, spec):
    563     """
    564     Do the work of reimaging hosts and running tests.
    565 
    566     @param suite: _BaseSuite instance to run.
    567     @param spec: a populated _SuiteSpec object.
    568     """
    569     _run_suite(
    570         suite=suite,
    571         job=spec.job,
    572         delay_minutes=spec.delay_minutes,
    573         bug_template=spec.bug_template)
    574 
    575 
    576 def _run_suite(
    577         suite,
    578         job,
    579         delay_minutes,
    580         bug_template):
    581     """
    582     Run a suite.
    583 
    584     @param suite: _BaseSuite instance.
    585     @param job: an instance of client.common_lib.base_job representing the
    586                 currently running suite job.
    587     @param delay_minutes: Delay the creation of test jobs for a given number
    588                           of minutes.
    589     @param bug_template: A template dictionary specifying the default bug
    590                          filing options for failures in this suite.
    591     """
    592     timestamp = datetime.datetime.now().strftime(time_utils.TIME_FMT)
    593     utils.write_keyval(
    594         job.resultdir,
    595         {constants.ARTIFACT_FINISHED_TIME: timestamp})
    596 
    597     if delay_minutes:
    598         logging.debug('delay_minutes is set. Sleeping %d minutes before '
    599                       'creating test jobs.', delay_minutes)
    600         time.sleep(delay_minutes*60)
    601         logging.debug('Finished waiting for %d minutes before creating test '
    602                       'jobs.', delay_minutes)
    603 
    604     # Now we get to asychronously schedule tests.
    605     suite.schedule(job.record_entry)
    606 
    607     if suite.wait_for_results:
    608         logging.debug('Waiting on suite.')
    609         suite.wait(job.record_entry)
    610         logging.debug('Finished waiting on suite. '
    611                       'Returning from _perform_reimage_and_run.')
    612     else:
    613         logging.info('wait_for_results is set to False, suite job will exit '
    614                      'without waiting for test jobs to finish.')
    615 
    616 
    617 def _stage_artifacts_for_build(devserver, build):
    618     """Stage artifacts for a suite job.
    619 
    620     @param devserver: devserver to stage artifacts with.
    621     @param build: image to stage artifacts for.
    622     """
    623     try:
    624         devserver.stage_artifacts(
    625                 image=build,
    626                 artifacts=['control_files', 'test_suites'])
    627     except dev_server.DevServerException as e:
    628         # If we can't get the control files, there's nothing to run.
    629         raise error.AsynchronousBuildFailure(e)
    630