Re: [PATCH 1/9] [RFC] Support named cgroups hierarchies

[Li Zefan <lizf@cn.fujitsu.com>]

>>>  /*
>>>   * A cgroupfs_root represents the root of a cgroup hierarchy,
>>>   * and may be associated with a superblock to form an active
>>> @@ -93,6 +95,9 @@ struct cgroupfs_root {
>>>
>>>       /* The path to use for release notifications. */
>>>       char release_agent_path[PATH_MAX];
>>> +
>>> +     /* The name for this hierarchy - may be empty */
>>> +     char name[MAX_CGROUP_ROOT_NAMELEN];
>>>  };
>>>
>> If you don't want to make cgroupfs_root bigger,
>>
>>        cgroupfs_root {
>>                ......
>>                /* this must be the bottom of struct */
>>                char name[0];
>>        }
>>
>> Is a choice.
> 
> I'd rather avoid something like that since I think it's less readable
> - I'd probably just make the name into a pointer in that case.
> 

Whichever choice we make, the length should be limited I think.

>> BTW, reading a patch, any kind of charactors are allowed ?
> 
> Yes, other than \000 of course. I guess maybe I should use
> seq_escape() to print the name to avoid confusion in the event that
> people put whitespace in there, or else just ban whitespace (or maybe
> all non-alphanumeric chars).
> 

I don't think we need to care about this.

mount -t cgroup -o debug xxx /mnt

"xxx" can be any chars.