openstack
/
neutron
Code Issues Proposed changes

Remove nested transaction from ipam driver 

Using nested transaction in reference ipam driver causes rewriting
original exception due failure to restore to safepoint in case of
DeadLock.

DBDeadlock exception gets replaced with DBAPIError. It prevents db_retry
wrapper from working correctly.

This patch removed nested transaction block from reference ipam driver.

Change-Id: Ib710e87b0132aae3cd3afd12c5448961f1a3b25c
Partial-Bug: #1571666
This commit is contained in:
Pavel Bondar 2016-04-18 17:56:08 +03:00
parent acca136721
commit ad2d7d3a8f
1 changed files with 22 additions and 26 deletions
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48
neutron/ipam/drivers/neutrondb_ipam/driver.py
View File

@ -21,7 +21,6 @@ from oslo_utils import uuidutils
from neutron._i18n import _, _LE
from neutron.common import ipv6_utils
from neutron.db import api as db_api
from neutron.ipam import driver as ipam_base
from neutron.ipam.drivers.neutrondb_ipam import db_api as ipam_db_api
from neutron.ipam import exceptions as ipam_exc
@ -326,34 +325,31 @@ class NeutronDbSubnet(ipam_base.Subnet):
return ip_address, ip_range['allocation_pool_id']
def allocate(self, address_request):
# NOTE(salv-orlando): Creating a new db session might be a rather
# dangerous thing to do, if executed from within another database
# transaction. Therefore the IPAM driver should never be
# called from within a database transaction, which is also good
# practice since in the general case these drivers may interact
# with remote backends
# NOTE(pbondar): Ipam driver is always called in context of already
# running transaction, which is started on create_port or upper level.
# To be able to do rollback/retry actions correctly ipam driver
# should not create new nested transaction blocks.
session = self._context.session
all_pool_id = None
auto_generated = False
with db_api.autonested_transaction(session):
# NOTE(salv-orlando): It would probably better to have a simpler
# model for address requests and just check whether there is a
# specific IP address specified in address_request
if isinstance(address_request, ipam_req.SpecificAddressRequest):
# This handles both specific and automatic address requests
# Check availability of requested IP
ip_address = str(address_request.address)
self._verify_ip(session, ip_address)
else:
ip_address, all_pool_id = self._generate_ip(session)
auto_generated = True
self._allocate_specific_ip(session, ip_address, all_pool_id,
auto_generated)
# Create IP allocation request object
# The only defined status at this stage is 'ALLOCATED'.
# More states will be available in the future - e.g.: RECYCLABLE
self.subnet_manager.create_allocation(session, ip_address)
return ip_address
# NOTE(salv-orlando): It would probably better to have a simpler
# model for address requests and just check whether there is a
# specific IP address specified in address_request
if isinstance(address_request, ipam_req.SpecificAddressRequest):
# This handles both specific and automatic address requests
# Check availability of requested IP
ip_address = str(address_request.address)
self._verify_ip(session, ip_address)
else:
ip_address, all_pool_id = self._generate_ip(session)
auto_generated = True
self._allocate_specific_ip(session, ip_address, all_pool_id,
auto_generated)
# Create IP allocation request object
# The only defined status at this stage is 'ALLOCATED'.
# More states will be available in the future - e.g.: RECYCLABLE
self.subnet_manager.create_allocation(session, ip_address)
return ip_address
def deallocate(self, address):
# This is almost a no-op because the Neutron DB IPAM driver does not