Re: [PATCH] mm/swap_state.c: use the same way to count page in [add_to|delete_from]_swap_cache

From: Wei Yang
Date: Sat Mar 14 2020 - 21:29:46 EST


On Sat, Mar 14, 2020 at 05:21:01PM -0700, Matthew Wilcox wrote:
>On Sat, Mar 14, 2020 at 09:59:12PM +0000, Wei Yang wrote:
>> Function add_to_swap_cache() and delete_from_swap_cache() are counter
>> parts, while currently they use different way to count page.
>>
>> It doesn't break any thing because we only have two size for PageAnon,
>> but this is confusing and not a good practice.
>>
>> This patch corrects it by both using compound_nr().
>
>You're converting in the wrong direction. hpage_nr_pages() is optimised
>away when CONFIG_TRANSPARENT_HUGEPAGE is undefined, whereas compound_nr()
>is not.

Ok, I didn't think about the optimisation.

Will use hpage_nr_pages() in v2.

>
>I also have this patch pending:
>http://git.infradead.org/users/willy/linux-dax.git/commitdiff/192b635b428ae74f680574cdcc3d5e9d213fcb64

--
Wei Yang
Help you, Help me