Re: [PATCH] mm/hugetlb: remove unnecessary memory fetch in PageHeadHuge()

From: Mike Kravetz
Date: Wed Mar 11 2020 - 14:20:33 EST


On 3/11/20 10:24 AM, Vlastimil Babka wrote:
> Commit f1e61557f023 ("mm: pack compound_dtor and compound_order into one word
> in struct page") changed compound_dtor from a pointer to an array index in
> order to pack it. To check if page has the hugeltbfs compound_dtor, we can
> just compare the index directly without fetching the function pointer.
> Said commit did that with PageHuge() and we can do the same with PageHeadHuge()
> to make the code a bit smaller and faster.
>
> Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
> Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

Thanks!

Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
--
Mike Kravetz