[YARN-6799] Remove the duplicated code in CGroupsHandlerImp.java

• Type: Improvement
• Status: Resolved
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 3.0.0-alpha3
• Fix Version/s: 2.9.0, 3.0.0-beta1
• Component/s: nodemanager
• Assignee: weiyuan
• Reporter: Yufei Gu
• Created: 10/Jul/17 21:03
• Updated: 15/Sep/17 16:56
• Resolved: 11/Sep/17 06:25

Description

The else clause in initializeCGroupController is not necessary.

  public void initializeCGroupController(CGroupController controller) throws
      ResourceHandlerException {
    if (enableCGroupMount) {
      // We have a controller that needs to be mounted
      mountCGroupController(controller);
    } else {
      String controllerPath = getControllerPath(controller);

      if (controllerPath == null) {
        throw new ResourceHandlerException(
            String.format("Controller %s not mounted."
                + " You either need to mount it with %s"
                + " or mount cgroups before launching Yarn",
                controller.getName(), YarnConfiguration.
                NM_LINUX_CONTAINER_CGROUPS_MOUNT));
      }
    }

    // We are working with a pre-mounted contoller
    // Make sure that Yarn cgroup hierarchy path exists
    initializePreMountedCGroupController(controller);
  }

  private void initializePreMountedCGroupController(CGroupController controller)
      throws ResourceHandlerException {
    // Check permissions to cgroup hierarchy and
    // create YARN cgroup if it does not exist, yet
    String controllerPath = getControllerPath(controller);

    if (controllerPath == null) {
      throw new ResourceHandlerException(
          String.format("Controller %s not mounted."
                  + " You either need to mount it with %s"
                  + " or mount cgroups before launching Yarn",
              controller.getName(), YarnConfiguration.
                  NM_LINUX_CONTAINER_CGROUPS_MOUNT));
    }