Merge lp:~camptocamp/ocb-server/7.0-registrymanager-rlock-1238560-gbr into lp:ocb-server

[Guewen Baconnier @ Camptocamp]

[FIX] missing a threading.RLock in RegistryManager.get():

if no registry exists and several calls to RegistryManager.get() are called at the same time
by several threads, several registries will be created one after the other and only the last
one will be kept in cls.registries

Fixes lp:1238560

Details on the bug report.

[Stéphane Bidoul (Acsone) (sbi)]

The lock seems mandatory to me too.

Is the get() method called frequently enough to warrant a double checked locking pattern in order to improve performance?

[Guewen Baconnier @ Camptocamp (gbaconnier-c2c)]

It has been merged in the 7.0 branch, so we don't need to merge it here.

revno: 5129 [merge]
revision-id: <email address hidden>

Unmerged revisions

5137. By Guewen Baconnier @ Camptocamp on 2013-11-04

[FIX] missing a threading.RLock in RegistryManager.get():

if no registry exists and several calls to RegistryManager.get() are called at the same time
by several threads, several registries will be created one after the other and only the last
one will be kept in cls.registries

=== modified file 'openerp/modules/registry.py'
--- openerp/modules/registry.py	2013-10-11 12:39:14 +0000
+++ openerp/modules/registry.py	2013-11-04 11:00:43 +0000
@@ -185,15 +185,16 @@
     @classmethod
     def get(cls, db_name, force_demo=False, status=None, update_module=False):
         """ Return a registry for a given database name."""
-        try:
-            return cls.registries[db_name]
-        except KeyError:
-            return cls.new(db_name, force_demo, status,
-                           update_module)
-        finally:
-            # set db tracker - cleaned up at the WSGI
-            # dispatching phase in openerp.service.wsgi_server.application
-            threading.current_thread().dbname = db_name
+        with cls.registries_lock:
+            try:
+                return cls.registries[db_name]
+            except KeyError:
+                return cls.new(db_name, force_demo, status,
+                               update_module)
+            finally:
+                # set db tracker - cleaned up at the WSGI
+                # dispatching phase in openerp.service.wsgi_server.application
+                threading.current_thread().dbname = db_name
 
     @classmethod
     def new(cls, db_name, force_demo=False, status=None,