1. 01 Apr, 2012 4 commits
    • Tejun Heo's avatar
      cgroup: implement cgroup_add_cftypes() and friends · 8e3f6541
      Tejun Heo authored
      
      
      Currently, cgroup directories are populated by subsys->populate()
      callback explicitly creating files on each cgroup creation.  This
      level of flexibility isn't needed or desirable.  It provides largely
      unused flexibility which call for abuses while severely limiting what
      the core layer can do through the lack of structure and conventions.
      
      Per each cgroup file type, the only distinction that cgroup users is
      making is whether a cgroup is root or not, which can easily be
      expressed with flags.
      
      This patch introduces cgroup_add_cftypes().  These deal with cftypes
      instead of individual files - controllers indicate that certain types
      of files exist for certain subsystem.  Newly added CFTYPE_*_ON_ROOT
      flags indicate whether a cftype should be excluded or created only on
      the root cgroup.
      
      cgroup_add_cftypes() can be called any time whether the target
      subsystem is currently attached or not.  cgroup core will create files
      on the existing cgroups as necessary.
      
      Also, cgroup_subsys->base_cftypes is added to ease registration of the
      base files for the subsystem.  If non-NULL on subsys init, the cftypes
      pointed to by ->base_cftypes are automatically registered on subsys
      init / load.
      
      Further patches will convert the existing users and remove the file
      based interface.  Note that this interface allows dynamic addition of
      files to an active controller.  This will be used for sub-controller
      modularity and unified hierarchy in the longer term.
      
      This patch implements the new mechanism but doesn't apply it to any
      user.
      
      v2: replaced DECLARE_CGROUP_CFTYPES[_COND]() with
          cgroup_subsys->base_cftypes, which works better for cgroup_subsys
          which is loaded as module.
      
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      8e3f6541
    • Tejun Heo's avatar
      cgroup: build list of all cgroups under a given cgroupfs_root · b0ca5a84
      Tejun Heo authored
      
      
      Build a list of all cgroups anchored at cgroupfs_root->allcg_list and
      going through cgroup->allcg_node.  The list is protected by
      cgroup_mutex and will be used to improve cgroup file handling.
      
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      b0ca5a84
    • Tejun Heo's avatar
      cgroup: move cgroup_clear_directory() call out of cgroup_populate_dir() · ff4c8d50
      Tejun Heo authored
      
      
      cgroup_populate_dir() currently clears all files and then repopulate
      the directory; however, the clearing part is only useful when it's
      called from cgroup_remount().  Relocate the invocation to
      cgroup_remount().
      
      This is to prepare for further cgroup file handling updates.
      
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      ff4c8d50
    • Tejun Heo's avatar
      cgroup: deprecate remount option changes · 8b5a5a9d
      Tejun Heo authored
      
      
      This patch marks the following features for deprecation.
      
      * Rebinding subsys by remount: Never reached useful state - only works
        on empty hierarchies.
      
      * release_agent update by remount: release_agent itself will be
        replaced with conventional fsnotify notification.
      
      v2: Lennart pointed out that "name=" is necessary for mounts w/o any
          controller attached.  Drop "name=" deprecation.
      
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      Cc: Lennart Poettering <mzxreary@0pointer.de>
      8b5a5a9d
  2. 31 Mar, 2012 36 commits