From mboxrd@z Thu Jan  1 00:00:00 1970
From: Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
Subject: Re: [PATCH 1/2] [RFC] Add file f_flags to cgroup write_string ops
Date: Wed, 28 Oct 2009 15:29:27 +0800
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To: Matt Helsley <matthltc-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
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>>>> I think maybe it's better to store struct file *file to struct cftype,
>>>> so we don't need to change write_string(), write(), write_u64()
>>>> and write_s64().
>>> We can't do that - multiple open files could be using the same cftype
>>> at the same time. I'd be inclined if necessary to just pass the struct
>>> file* in, rather than risk needing to change it to pass more
>>> parameters later.
>> And I imagine that the number of handlers that actually make use of
>> the cftype* is rather small. If we pass the file* to the handler
>> instead of passing the cftype*, and provide an inline function to get
>> from the file* to the cftype*, then we can avoid adding an extra
>> parameter to the handlers.
> 
> OK, I've done this for write_string(). I named the inline function
> cgroup_file_cftype(). It seems that, if we do this for one, then 
> we should do it for all of the cgroup file io ops. Agreed?
> 

I think so, to make interfaces consistent.