Re: [PATCH 7/7] cgroups: Update documentation for bindable subsystems

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

Li Zefan wrote:
> KAMEZAWA Hiroyuki wrote:
>> On Fri, 22 Oct 2010 16:12:25 +0800
>> Li Zefan <lizf@cn.fujitsu.com> wrote:
>>
>>> Provide a usage example, and update the bind() callback API.
>>>
>>> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
>>> ---
>>>  Documentation/cgroups/cgroups.txt |   26 +++++++++++++++++---------
>>>  1 files changed, 17 insertions(+), 9 deletions(-)
>>>
>>> diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt
>>> index 190018b..5b5382a 100644
>>> --- a/Documentation/cgroups/cgroups.txt
>>> +++ b/Documentation/cgroups/cgroups.txt
>>> @@ -363,17 +363,23 @@ Note this will add ns to the hierarchy but won't remove memory or
>>>  cpuset, because the new options are appended to the old ones:
>>>  # mount -o remount,ns /dev/cgroup
>>>  
>>> +For some subsystems you can bind them to a mounted hierarchy or
>>> +remove them from it, even if there're sub-cgroups in it:
>>> +# mount -t cgroup -o freezer hier1 /dev/cgroup
>>> +# echo $$ > /dev/cgroup/my_cgroup
>>> +# mount -o freezer,cpuset hier1 /dev/cgroup
>>> +(failed)
>>> +# mount -o freezer,cpuacct hier1 /dev/cgroup
>>> +# mount -o cpuacct hier1 /dev/cgroup
>>> +
>>> +Note cpuacct should be sit in the default hierarchy before remount.
>>> +
>> Can this operation be used with noop cgroup ?
>> (IOW, perf cgroup can be attached to noop cgroup ?)
>>
> 
> Yes, you can. I've tested it.

But, wait. It stuck when I moved a task from a sub-cgroup to the root.
Need to dig more..