Re: [RESEND PATCH] fs/super.c set_anon_super calling optimization

From: Abhijit Pawar
Date: Fri Nov 30 2012 - 00:40:20 EST


On 11/30/2012 09:35 AM, Al Viro wrote:
> On Fri, Oct 26, 2012 at 11:14:41AM -0200, Carlos Maiolino wrote:
>> Hi,
>>
>> On Thu, Oct 25, 2012 at 05:08:19PM +0530, Abhijit Pawar wrote:
>>> Hi,
>>> set_anon_super is called by many filesystems. Some call directly and
>>> some call through the wrapper. Many of them in the wrapper's call to
>>> this function are passing the second argument to this function which
>>> is not used anywhere.
>>>
>>> This patch replaces the second variable with NULL.
>>>
>>
>> If the variable isn't used anymore, why don't just get rid of it, instead of
>> call the function passing a NULL pointer on it?
>
> Because we want it to be a valid sget() callback. I doubt that this
> optimization is worth doing, though - might even micro-pessimize the things
> on architectures where all arguments are passed in registers.
>
Al,
Yes. it will be helpful in registers case.

--
-
Abhijit
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