Fix the mapping of module_name to Locks

This was reinitialized every time we forked before so we weren't sharing
the same Locks.  It also was not accounting for modules which were
directly invoked by an action plugin instead of going through the
strategy plguins.
This commit is contained in:
Toshio Kuratomi 2016-04-29 20:47:51 -07:00
parent 1d6608e84f
commit 98feafb411
2 changed files with 55 additions and 15 deletions

View file

@ -34,7 +34,10 @@ from ansible.release import __version__, __author__
from ansible import constants as C
from ansible.errors import AnsibleError
from ansible.utils.unicode import to_bytes, to_unicode
from ansible.plugins.strategy import action_write_locks
# Must import strategy and use write_locks from there
# If we import write_locks directly then we end up binding a
# variable to the object and then it never gets updated.
from ansible.plugins import strategy
try:
from __main__ import display
@ -552,14 +555,29 @@ def _find_snippet_imports(module_name, module_data, module_path, module_args, ta
zipdata = None
# Optimization -- don't lock if the module has already been cached
if os.path.exists(cached_module_filename):
display.debug('ZIPLOADER: using cached module: %s' % cached_module_filename)
zipdata = open(cached_module_filename, 'rb').read()
# Fool the check later... I think we should just remove the check
py_module_names.add(('basic',))
else:
with action_write_locks[module_name]:
if module_name in strategy.action_write_locks:
display.debug('ZIPLOADER: Using lock for %s' % module_name)
lock = strategy.action_write_locks[module_name]
else:
# If the action plugin directly invokes the module (instead of
# going through a strategy) then we don't have a cross-process
# Lock specifically for this module. Use the "unexpected
# module" lock instead
display.debug('ZIPLOADER: Using generic lock for %s' % module_name)
lock = strategy.action_write_locks[None]
display.debug('ZIPLOADER: Acquiring lock')
with lock:
display.debug('ZIPLOADER: Lock acquired: %s' % id(lock))
# Check that no other process has created this while we were
# waiting for the lock
if not os.path.exists(cached_module_filename):
display.debug('ZIPLOADER: Creating module')
# Create the module zip data
zipoutput = BytesIO()
zf = zipfile.ZipFile(zipoutput, mode='w', compression=compression_method)
@ -580,15 +598,19 @@ def _find_snippet_imports(module_name, module_data, module_path, module_args, ta
# Note -- if we have a global function to setup, that would
# be a better place to run this
os.mkdir(lookup_path)
display.debug('ZIPLOADER: Writing module')
with open(cached_module_filename + '-part', 'w') as f:
f.write(zipdata)
# Rename the file into its final position in the cache so
# future users of this module can read it off the
# filesystem instead of constructing from scratch.
display.debug('ZIPLOADER: Renaming module')
os.rename(cached_module_filename + '-part', cached_module_filename)
display.debug('ZIPLOADER: Done creating module')
if zipdata is None:
display.debug('ZIPLOADER: Reading module after lock')
# Another process wrote the file while we were waiting for
# the write lock. Go ahead and read the data from disk
# instead of re-creating it.

View file

@ -36,6 +36,7 @@ from ansible.executor.process.worker import WorkerProcess
from ansible.executor.task_result import TaskResult
from ansible.inventory.host import Host
from ansible.inventory.group import Group
from ansible.module_utils.facts import Facts
from ansible.playbook.helpers import load_list_of_blocks
from ansible.playbook.included_file import IncludedFile
from ansible.plugins import action_loader, connection_loader, filter_loader, lookup_loader, module_loader, test_loader
@ -52,8 +53,24 @@ except ImportError:
__all__ = ['StrategyBase']
action_write_locks = defaultdict(Lock)
if 'action_write_locks' not in globals():
# Do not initialize this more than once because it seems to bash
# the existing one. multiprocessing must be reloading the module
# when it forks?
action_write_locks = dict()
# Below is a Lock for use when we weren't expecting a named module.
# It gets used when an action plugin directly invokes a module instead
# of going through the strategies. Slightly less efficient as all
# processes with unexpected module names will wait on this lock
action_write_locks[None] = Lock()
# These plugins are called directly by action plugins (not going through
# a strategy). We precreate them here as an optimization
mods = set(p['name'] for p in Facts.PKG_MGRS)
mods.update(('copy', 'file', 'setup', 'slurp', 'stat'))
for mod_name in mods:
action_write_locks[mod_name] = Lock()
# TODO: this should probably be in the plugins/__init__.py, with
# a smarter mechanism to set all of the attributes based on
@ -144,18 +161,19 @@ class StrategyBase:
display.debug("entering _queue_task() for %s/%s" % (host, task))
# Add a write lock for tasks.
# Maybe this should be added somewhere further up the call stack but
# this is the earliest in the code where we have task (1) extracted
# into its own variable and (2) there's only a single code path
# leading to the module being run. This is called by three
# functions: __init__.py::_do_handler_run(), linear.py::run(), and
# free.py::run() so we'd have to add to all three to do it there.
# The next common higher level is __init__.py::run() and that has
# tasks inside of play_iterator so we'd have to extract them to do it
# there.
if not action_write_locks[task.action]:
display.warning('Python defaultdict did not create the Lock for us. Creating manually')
# Add a write lock for tasks.
# Maybe this should be added somewhere further up the call stack but
# this is the earliest in the code where we have task (1) extracted
# into its own variable and (2) there's only a single code path
# leading to the module being run. This is called by three
# functions: __init__.py::_do_handler_run(), linear.py::run(), and
# free.py::run() so we'd have to add to all three to do it there.
# The next common higher level is __init__.py::run() and that has
# tasks inside of play_iterator so we'd have to extract them to do it
# there.
global action_write_locks
if task.action not in action_write_locks:
display.debug('Creating lock for %s' % task.action)
action_write_locks[task.action] = Lock()
# and then queue the new task