from ganeti import utils
from ganeti import errors
from ganeti import hypervisor
+from ganeti import locking
from ganeti import config
from ganeti import constants
from ganeti import objects
"""Logical Unit base class.
Subclasses must follow these rules:
- - implement CheckPrereq which also fills in the opcode instance
- with all the fields (even if as None)
+ - implement ExpandNames
+ - implement CheckPrereq
- implement Exec
- implement BuildHooksEnv
- redefine HPATH and HTYPE
self.cfg = context.cfg
self.sstore = sstore
self.context = context
+ self.needed_locks = None
self.__ssh = None
for attr_name in self._OP_REQP:
ssh = property(fget=__GetSSH)
+ def ExpandNames(self):
+ """Expand names for this LU.
+
+ This method is called before starting to execute the opcode, and it should
+ update all the parameters of the opcode to their canonical form (e.g. a
+ short node name must be fully expanded after this method has successfully
+ completed). This way locking, hooks, logging, ecc. can work correctly.
+
+ LUs which implement this method must also populate the self.needed_locks
+ member, as a dict with lock levels as keys, and a list of needed lock names
+ as values. Rules:
+ - Use an empty dict if you don't need any lock
+ - If you don't need any lock at a particular level omit that level
+ - Don't put anything for the BGL level
+ - If you want all locks at a level use None as a value
+ (this reflects what LockSet does, and will be replaced before
+ CheckPrereq with the full list of nodes that have been locked)
+
+ Examples:
+ # Acquire all nodes and one instance
+ self.needed_locks = {
+ locking.LEVEL_NODE: None,
+ locking.LEVEL_INSTANCES: ['instance1.example.tld'],
+ }
+ # Acquire just two nodes
+ self.needed_locks = {
+ locking.LEVEL_NODE: ['node1.example.tld', 'node2.example.tld'],
+ }
+ # Acquire no locks
+ self.needed_locks = {} # No, you can't leave it to the default value None
+
+ """
+ # The implementation of this method is mandatory only if the new LU is
+ # concurrent, so that old LUs don't need to be changed all at the same
+ # time.
+ if self.REQ_BGL:
+ self.needed_locks = {} # Exclusive LUs don't need locks.
+ else:
+ raise NotImplementedError
+
def CheckPrereq(self):
"""Check prerequisites for this LU.
not fulfilled. Its return value is ignored.
This method should also update all the parameters of the opcode to
- their canonical form; e.g. a short node name must be fully
- expanded after this method has successfully completed (so that
- hooks, logging, etc. work correctly).
+ their canonical form if it hasn't been done by ExpandNames before.
"""
raise NotImplementedError
"""
return lu_result
+ def _ExpandAndLockInstance(self):
+ """Helper function to expand and lock an instance.
+
+ Many LUs that work on an instance take its name in self.op.instance_name
+ and need to expand it and then declare the expanded name for locking. This
+ function does it, and then updates self.op.instance_name to the expanded
+ name. It also initializes needed_locks as a dict, if this hasn't been done
+ before.
+
+ """
+ if self.needed_locks is None:
+ self.needed_locks = {}
+ else:
+ assert locking.LEVEL_INSTANCE not in self.needed_locks, \
+ "_ExpandAndLockInstance called with instance-level locks set"
+ expanded_name = self.cfg.ExpandInstanceName(self.op.instance_name)
+ if expanded_name is None:
+ raise errors.OpPrereqError("Instance '%s' not known" %
+ self.op.instance_name)
+ self.needed_locks[locking.LEVEL_INSTANCE] = expanded_name
+ self.op.instance_name = expanded_name
+
class NoHooksLU(LogicalUnit):
"""Simple LU which runs no hooks.
if done or oneshot:
break
- if unlock:
- #utils.Unlock('cmd')
- pass
- try:
- time.sleep(min(60, max_time))
- finally:
- if unlock:
- #utils.Lock('cmd')
- pass
+ time.sleep(min(60, max_time))
if done:
proc.LogInfo("Instance %s's disks are in sync." % instance.name)
"""
_OP_REQP = []
REQ_MASTER = False
+ REQ_BGL = False
+
+ def ExpandNames(self):
+ self.needed_locks = {}
def CheckPrereq(self):
"""No prerequsites needed for this LU.
"""
_OP_REQP = []
+ REQ_BGL = False
+
+ def ExpandNames(self):
+ self.needed_locks = {}
def CheckPrereq(self):
"""No prerequisites.
"""
_OP_REQP = ["instance_name"]
+ REQ_BGL = False
+
+ def ExpandNames(self):
+ self._ExpandAndLockInstance()
def CheckPrereq(self):
"""Check prerequisites.
This checks that the instance is in the cluster.
"""
- instance = self.cfg.GetInstanceInfo(
- self.cfg.ExpandInstanceName(self.op.instance_name))
- if instance is None:
- raise errors.OpPrereqError("Instance '%s' not known" %
- self.op.instance_name)
- self.instance = instance
+ self.instance = self.cfg.GetInstanceInfo(self.op.instance_name)
+ assert self.instance is not None, \
+ "Cannot retrieve locked instance %s" % self.op.instance_name
def Exec(self, feedback_fn):
"""Connect to the console of an instance
HPATH = "instance-modify"
HTYPE = constants.HTYPE_INSTANCE
_OP_REQP = ["instance_name"]
+ REQ_BGL = False
+
+ def ExpandNames(self):
+ self._ExpandAndLockInstance()
def BuildHooksEnv(self):
"""Build hooks env.
This only checks the instance list against the existing names.
"""
+ # FIXME: all the parameters could be checked before, in ExpandNames, or in
+ # a separate CheckArguments function, if we implement one, so the operation
+ # can be aborted without waiting for any lock, should it have an error...
self.mem = getattr(self.op, "mem", None)
self.vcpus = getattr(self.op, "vcpus", None)
self.ip = getattr(self.op, "ip", None)
" like a valid IP address" %
self.op.vnc_bind_address)
- instance = self.cfg.GetInstanceInfo(
- self.cfg.ExpandInstanceName(self.op.instance_name))
- if instance is None:
- raise errors.OpPrereqError("No such instance name '%s'" %
- self.op.instance_name)
- self.op.instance_name = instance.name
- self.instance = instance
+ self.instance = self.cfg.GetInstanceInfo(self.op.instance_name)
+ assert self.instance is not None, \
+ "Cannot retrieve locked instance %s" % self.op.instance_name
return
def Exec(self, feedback_fn):
instance.vnc_bind_address = self.vnc_bind_address
result.append(("vnc_bind_address", self.vnc_bind_address))
- self.cfg.AddInstance(instance)
+ self.cfg.Update(instance)
return result
" config file and the operation has been"
" aborted. Please retry.")
+
class LUTestDelay(NoHooksLU):
"""Sleep for a specified amount of time.
"""
_OP_REQP = ["duration", "on_master", "on_nodes"]
+ REQ_BGL = False
- def CheckPrereq(self):
- """Check prerequisites.
+ def ExpandNames(self):
+ """Expand names and set required locks.
- This checks that we have a good list of nodes and/or the duration
- is valid.
+ This expands the node list, if any.
"""
-
+ self.needed_locks = {}
if self.op.on_nodes:
+ # _GetWantedNodes can be used here, but is not always appropriate to use
+ # this way in ExpandNames. Check LogicalUnit.ExpandNames docstring for
+ # more information.
self.op.on_nodes = _GetWantedNodes(self, self.op.on_nodes)
+ self.needed_locks[locking.LEVEL_NODE] = self.op.on_nodes
+
+ def CheckPrereq(self):
+ """Check prerequisites.
+
+ """
def Exec(self, feedback_fn):
"""Do the actual sleep.
projects / ganeti-local / blobdiff