From: Zhongyue Luo <zhongyue.nah@intel.com>
Date: Tue, 14 May 2013 09:30:00 +0000 (+0800)
Subject: Hide lock_prefix argument using synchronized_with_prefix()
X-Git-Url: https://review.fuel-infra.org/gitweb?a=commitdiff_plain;h=197fbf154aafaf70363f5f1377a9495d0559436b;p=openstack-build%2Fcinder-build.git

Hide lock_prefix argument using synchronized_with_prefix()

The lockfile module has a new convenience API which sets the lockfile prefix
Using this API, the prefix is not required everytime synchronized is used.

Change-Id: I033fa1d2ed071651609ac2be0a5a16eb3fda6c33
---

diff --git a/cinder/openstack/common/lockutils.py b/cinder/openstack/common/lockutils.py
index 0c6b26c41..f21f0d918 100644
--- a/cinder/openstack/common/lockutils.py
+++ b/cinder/openstack/common/lockutils.py
@@ -49,6 +49,10 @@ CONF = cfg.CONF
 CONF.register_opts(util_opts)
 
 
+def set_defaults(lock_path):
+    cfg.set_defaults(util_opts, lock_path=lock_path)
+
+
 class _InterProcessLock(object):
     """Lock implementation which allows multiple locks, working around
     issues like bugs.debian.org/cgi-bin/bugreport.cgi?bug=632857 and does
@@ -82,7 +86,7 @@ class _InterProcessLock(object):
                 # to have a laughable 10 attempts "blocking" mechanism.
                 self.trylock()
                 return self
-            except IOError, e:
+            except IOError as e:
                 if e.errno in (errno.EACCES, errno.EAGAIN):
                     # external locks synchronise things like iptables
                     # updates - give it some time to prevent busy spinning
@@ -247,3 +251,28 @@ def synchronized(name, lock_file_prefix, external=False, lock_path=None):
             return retval
         return inner
     return wrap
+
+
+def synchronized_with_prefix(lock_file_prefix):
+    """Partial object generator for the synchronization decorator.
+
+    Redefine @synchronized in each project like so::
+
+        (in nova/utils.py)
+        from nova.openstack.common import lockutils
+
+        synchronized = lockutils.synchronized_with_prefix('nova-')
+
+
+        (in nova/foo.py)
+        from nova import utils
+
+        @utils.synchronized('mylock')
+        def bar(self, *args):
+           ...
+
+    The lock_file_prefix argument is used to provide lock files on disk with a
+    meaningful prefix. The prefix should end with a hyphen ('-') if specified.
+    """
+
+    return functools.partial(synchronized, lock_file_prefix=lock_file_prefix)
diff --git a/cinder/utils.py b/cinder/utils.py
index 65128be4a..dc4e47e90 100644
--- a/cinder/utils.py
+++ b/cinder/utils.py
@@ -56,6 +56,7 @@ from cinder import exception
 from cinder import flags
 from cinder.openstack.common import excutils
 from cinder.openstack.common import importutils
+from cinder.openstack.common import lockutils
 from cinder.openstack.common import log as logging
 from cinder.openstack.common import timeutils
 
@@ -65,6 +66,8 @@ ISO_TIME_FORMAT = "%Y-%m-%dT%H:%M:%S"
 PERFECT_TIME_FORMAT = "%Y-%m-%dT%H:%M:%S.%f"
 FLAGS = flags.FLAGS
 
+synchronized = lockutils.synchronized_with_prefix('cinder-')
+
 
 def find_config(config_path):
     """Find a configuration file using the given hint.
diff --git a/cinder/volume/drivers/netapp/iscsi.py b/cinder/volume/drivers/netapp/iscsi.py
index 32cefd366..d67a2b578 100644
--- a/cinder/volume/drivers/netapp/iscsi.py
+++ b/cinder/volume/drivers/netapp/iscsi.py
@@ -32,8 +32,8 @@ from suds import client
 from suds.sax import text
 
 from cinder import exception
-from cinder.openstack.common import lockutils
 from cinder.openstack.common import log as logging
+from cinder import utils
 from cinder.volume import driver
 from cinder.volume.drivers.netapp.api import NaApiError
 from cinder.volume.drivers.netapp.api import NaElement
@@ -388,7 +388,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         self.discovered_datasets.append(ds)
         return ds
 
-    @lockutils.synchronized('netapp_dfm', 'cinder-', True)
+    @utils.synchronized('netapp_dfm', external=True)
     def _provision(self, name, description, project, ss_type, size):
         """Provision a LUN through provisioning manager.
 
@@ -449,7 +449,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
             return None
         return volume_type['name']
 
-    @lockutils.synchronized('netapp_dfm', 'cinder-', True)
+    @utils.synchronized('netapp_dfm', external=True)
     def _remove_destroy(self, name, project):
         """Remove the LUN from the dataset, also destroying it.
 
diff --git a/cinder/volume/drivers/san/hp/hp_3par_common.py b/cinder/volume/drivers/san/hp/hp_3par_common.py
index bed8cc39d..88be95163 100644
--- a/cinder/volume/drivers/san/hp/hp_3par_common.py
+++ b/cinder/volume/drivers/san/hp/hp_3par_common.py
@@ -50,7 +50,6 @@ from oslo.config import cfg
 
 from cinder import context
 from cinder import exception
-from cinder.openstack.common import lockutils
 from cinder.openstack.common import log as logging
 from cinder import utils
 from cinder.volume import volume_types
@@ -597,7 +596,7 @@ exit
 
         return status
 
-    @lockutils.synchronized('3parclone', 'cinder-', True)
+    @utils.synchronized('3parclone', external=True)
     def create_cloned_volume(self, volume, src_vref, client):
 
         try:
diff --git a/cinder/volume/drivers/san/hp/hp_3par_fc.py b/cinder/volume/drivers/san/hp/hp_3par_fc.py
index d5af46d3e..7af686268 100644
--- a/cinder/volume/drivers/san/hp/hp_3par_fc.py
+++ b/cinder/volume/drivers/san/hp/hp_3par_fc.py
@@ -35,8 +35,8 @@ from hp3parclient import exceptions as hpexceptions
 from oslo.config import cfg
 
 from cinder import exception
-from cinder.openstack.common import lockutils
 from cinder.openstack.common import log as logging
+from cinder import utils
 import cinder.volume.driver
 from cinder.volume.drivers.san.hp import hp_3par_common as hpcommon
 from cinder.volume.drivers.san import san
@@ -117,7 +117,7 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
         """Returns an error if prerequisites aren't met."""
         self._check_flags()
 
-    @lockutils.synchronized('3par-vol', 'cinder-', True)
+    @utils.synchronized('3par-vol', external=True)
     def create_volume(self, volume):
         metadata = self.common.create_volume(volume, self.client)
         return {'metadata': metadata}
@@ -127,11 +127,11 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
                                                    self.client)
         return {'metadata': new_vol}
 
-    @lockutils.synchronized('3par-vol', 'cinder-', True)
+    @utils.synchronized('3par-vol', external=True)
     def delete_volume(self, volume):
         self.common.delete_volume(volume, self.client)
 
-    @lockutils.synchronized('3par-vol', 'cinder-', True)
+    @utils.synchronized('3par-vol', external=True)
     def create_volume_from_snapshot(self, volume, snapshot):
         """
         Creates a volume from a snapshot.
@@ -140,15 +140,15 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
         """
         self.common.create_volume_from_snapshot(volume, snapshot, self.client)
 
-    @lockutils.synchronized('3par-snap', 'cinder-', True)
+    @utils.synchronized('3par-snap', external=True)
     def create_snapshot(self, snapshot):
         self.common.create_snapshot(snapshot, self.client)
 
-    @lockutils.synchronized('3par-snap', 'cinder-', True)
+    @utils.synchronized('3par-snap', external=True)
     def delete_snapshot(self, snapshot):
         self.common.delete_snapshot(snapshot, self.client)
 
-    @lockutils.synchronized('3par-attach', 'cinder-', True)
+    @utils.synchronized('3par-attach', external=True)
     def initialize_connection(self, volume, connector):
         """Assigns the volume to a server.
 
@@ -200,7 +200,7 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
                          'target_wwn': ports['FC']}}
         return info
 
-    @lockutils.synchronized('3par-attach', 'cinder-', True)
+    @utils.synchronized('3par-attach', external=True)
     def terminate_connection(self, volume, connector, force):
         """
         Driver entry point to unattach a volume from an instance.
@@ -246,14 +246,14 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
 
         return host
 
-    @lockutils.synchronized('3par-exp', 'cinder-', True)
+    @utils.synchronized('3par-exp', external=True)
     def create_export(self, context, volume):
         pass
 
-    @lockutils.synchronized('3par-exp', 'cinder-', True)
+    @utils.synchronized('3par-exp', external=True)
     def ensure_export(self, context, volume):
         pass
 
-    @lockutils.synchronized('3par-exp', 'cinder-', True)
+    @utils.synchronized('3par-exp', external=True)
     def remove_export(self, context, volume):
         pass
diff --git a/cinder/volume/drivers/san/hp/hp_3par_iscsi.py b/cinder/volume/drivers/san/hp/hp_3par_iscsi.py
index fca9c2006..f1b1b8355 100644
--- a/cinder/volume/drivers/san/hp/hp_3par_iscsi.py
+++ b/cinder/volume/drivers/san/hp/hp_3par_iscsi.py
@@ -34,8 +34,8 @@ from hp3parclient import client
 from hp3parclient import exceptions as hpexceptions
 
 from cinder import exception
-from cinder.openstack.common import lockutils
 from cinder.openstack.common import log as logging
+from cinder import utils
 import cinder.volume.driver
 from cinder.volume.drivers.san.hp import hp_3par_common as hpcommon
 from cinder.volume.drivers.san import san
@@ -119,7 +119,7 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
         """Returns an error if prerequisites aren't met."""
         self._check_flags()
 
-    @lockutils.synchronized('3par-vol', 'cinder-', True)
+    @utils.synchronized('3par-vol', external=True)
     def create_volume(self, volume):
         metadata = self.common.create_volume(volume, self.client)
 
@@ -137,11 +137,11 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
                  self.configuration.iscsi_port),
                 'metadata': new_vol}
 
-    @lockutils.synchronized('3par-vol', 'cinder-', True)
+    @utils.synchronized('3par-vol', external=True)
     def delete_volume(self, volume):
         self.common.delete_volume(volume, self.client)
 
-    @lockutils.synchronized('3par-vol', 'cinder-', True)
+    @utils.synchronized('3par-vol', external=True)
     def create_volume_from_snapshot(self, volume, snapshot):
         """
         Creates a volume from a snapshot.
@@ -150,15 +150,15 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
         """
         self.common.create_volume_from_snapshot(volume, snapshot, self.client)
 
-    @lockutils.synchronized('3par-snap', 'cinder-', True)
+    @utils.synchronized('3par-snap', external=True)
     def create_snapshot(self, snapshot):
         self.common.create_snapshot(snapshot, self.client)
 
-    @lockutils.synchronized('3par-snap', 'cinder-', True)
+    @utils.synchronized('3par-snap', external=True)
     def delete_snapshot(self, snapshot):
         self.common.delete_snapshot(snapshot, self.client)
 
-    @lockutils.synchronized('3par-attach', 'cinder-', True)
+    @utils.synchronized('3par-attach', external=True)
     def initialize_connection(self, volume, connector):
         """Assigns the volume to a server.
 
@@ -205,7 +205,7 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
                 }
         return info
 
-    @lockutils.synchronized('3par-attach', 'cinder-', True)
+    @utils.synchronized('3par-attach', external=True)
     def terminate_connection(self, volume, connector, force):
         """
         Driver entry point to unattach a volume from an instance.
@@ -266,14 +266,14 @@ must be the same" % (cpg['domain'], self.configuration.hp3par_domain)
 
         return host
 
-    @lockutils.synchronized('3par-exp', 'cinder-', True)
+    @utils.synchronized('3par-exp', external=True)
     def create_export(self, context, volume):
         pass
 
-    @lockutils.synchronized('3par-exp', 'cinder-', True)
+    @utils.synchronized('3par-exp', external=True)
     def ensure_export(self, context, volume):
         pass
 
-    @lockutils.synchronized('3par-exp', 'cinder-', True)
+    @utils.synchronized('3par-exp', external=True)
     def remove_export(self, context, volume):
         pass
diff --git a/cinder/volume/manager.py b/cinder/volume/manager.py
index 5ae2b28f1..fecbffe22 100644
--- a/cinder/volume/manager.py
+++ b/cinder/volume/manager.py
@@ -50,11 +50,11 @@ from cinder.image import glance
 from cinder import manager
 from cinder.openstack.common import excutils
 from cinder.openstack.common import importutils
-from cinder.openstack.common import lockutils
 from cinder.openstack.common import log as logging
 from cinder.openstack.common import timeutils
 from cinder.openstack.common import uuidutils
 from cinder import quota
+from cinder import utils
 from cinder.volume.configuration import Configuration
 from cinder.volume import utils as volume_utils
 from cinder.volume import volume_types
@@ -541,7 +541,7 @@ class VolumeManager(manager.SchedulerDependentManager):
     def attach_volume(self, context, volume_id, instance_uuid, mountpoint):
         """Updates db to show volume is attached"""
 
-        @lockutils.synchronized(volume_id, 'cinder-', external=True)
+        @utils.synchronized(volume_id, external=True)
         def do_attach():
             # check the volume status before attaching
             volume = self.db.volume_get(context, volume_id)