code: public ServiceFuture<OperationStatusResponseInner> beginStartOSUpgradeAsync(String resourceGroupName, String vmScaleSetName, final ServiceCallback<OperationStatusResponseInner> serviceCallback) {
          return ServiceFuture.fromResponse(beginStartOSUpgradeWithServiceResponseAsync(resourceGroupName, vmScaleSetName), serviceCallback);
      }
docs: Starts a rolling upgrade to move all virtual machine scale set instances to the latest available Platform Image OS version. Instances which are already running the latest available OS version are not affected.
  
  @param resourceGroupName The name of the resource group.
  @param vmScaleSetName The name of the VM scale set.
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object