Re: [PATCH v1 02/17] mm: factor out large folio handling from folio_nr_pages() into folio_large_nr_pages()

[David Hildenbrand <david@redhat.com>]

On 23.10.24 13:18, Kirill A. Shutemov wrote:
> On Thu, Aug 29, 2024 at 06:56:05PM +0200, David Hildenbrand wrote:
>> Let's factor it out into a simple helper function. This helper will
>> also come in handy when working with code where we know that our
>> folio is large.
>>
>> Make use of it in internal.h and mm.h, where applicable.
>>
>> While at it, let's consistently return a "long" value from all these
>> similar functions. Note that we cannot use "unsigned int" (even though
>> _folio_nr_pages is of that type), because it would break some callers
>> that do stuff like "-folio_nr_pages()". Both "int" or "unsigned long"
>> would work as well.
>>
>> Signed-off-by: David Hildenbrand <david@redhat.com>
>> ---
>>   include/linux/mm.h | 27 ++++++++++++++-------------
>>   mm/internal.h      |  2 +-
>>   2 files changed, 15 insertions(+), 14 deletions(-)
>>
>> diff --git a/include/linux/mm.h b/include/linux/mm.h
>> index 3c6270f87bdc3..fa8b6ce54235c 100644
>> --- a/include/linux/mm.h
>> +++ b/include/linux/mm.h
>> @@ -1076,6 +1076,15 @@ static inline unsigned int folio_large_order(const struct folio *folio)
>>   	return folio->_flags_1 & 0xff;
>>   }
>>   
>> +static inline long folio_large_nr_pages(const struct folio *folio)
>> +{
>> +#ifdef CONFIG_64BIT
>> +	return folio->_folio_nr_pages;
>> +#else
>> +	return 1L << folio_large_order(folio);
>> +#endif
>> +}
>> +
> 
> Maybe it would be cleaner to move #ifdef outside of the function?

Yes, can do that.

-- 
Cheers,

David / dhildenb