Synnefo » snf-ganeti

    adding_locks = level in lu.add_locks

    acquiring_locks = level in lu.needed_locks

    elif adding_locks and acquiring_locks:

      # We could both acquire and add locks at the same level, but for now we

      # don't need this, so we'll avoid the complicated code needed.

      raise NotImplementedError(

        "Can't declare locks to acquire when adding others")

    elif adding_locks or acquiring_locks:

      if acquiring_locks:

        needed_locks = lu.needed_locks[level]

        lu.acquired_locks[level] = self.context.glm.acquire(level,

                                                            needed_locks,

                                                            shared=share)

      else: # adding_locks

        add_locks = lu.add_locks[level]

        lu.remove_locks[level] = add_locks

        try:

          self.context.glm.add(level, add_locks, acquired=1, shared=share)

        except errors.LockError:

          raise errors.OpPrereqError(

            "Coudn't add locks (%s), probably because of a race condition"

            " with another job, who added them first" % add_locks)

        try:

          if adding_locks:

            lu.acquired_locks[level] = add_locks

          result = self._LockAndExecLU(lu, level + 1)

        finally:

          if level in lu.remove_locks:

            self.context.glm.remove(level, lu.remove_locks[level])