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Subject: Re: [PATCH 02/19] mm/gup: factor out duplicate code from four routines
To: Ira Weiny <ira.weiny@intel.com>
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From: John Hubbard <jhubbard@nvidia.com>
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Date: Thu, 31 Oct 2019 15:01:07 -0700
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On 10/31/19 2:09 PM, Ira Weiny wrote:
> On Thu, Oct 31, 2019 at 11:43:37AM -0700, John Hubbard wrote:
>> On 10/31/19 11:35 AM, Ira Weiny wrote:
>>> On Wed, Oct 30, 2019 at 03:49:13PM -0700, John Hubbard wrote:
>> ...
>>>> +
>>>> +static int __huge_pt_done(struct page *head, int nr_recorded_pages, int *nr)
>>>> +{
>>>> +	*nr += nr_recorded_pages;
>>>> +	SetPageReferenced(head);
>>>> +	return 1;
>>>
>>> When will this return anything but 1?
>>>
>>
>> Never, but it saves a line at all four call sites, by having it return like that.
>>
>> I could see how maybe people would prefer to just have it be a void function,
>> and return 1 directly at the call sites. Since this was a lower line count I
>> thought maybe it would be slightly better, but it's hard to say really.
> 
> It is a NIT perhaps but I feel like the signature of a function should stand on
> it's own.  What this does is mix the meaning of this function with those
> calling it.  Which IMO is not good style.
> 
> We can see what others say.
> 

Sure. I'll plan on changing it to a void return type, then, unless someone else
pipes up.


thanks,

John Hubbard
NVIDIA