Re: [PATCH] hugetlb: document the new location of page subpool pointer

[Oscar Salvador]

On Tue, Feb 23, 2021 at 08:04:39PM -0800, Mike Kravetz wrote:
> Expand comments, no functional change.
> 
> Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>

Reviewed-by: Oscar Salvador <osalvador@xxxxxxx>

Thanks

> ---
>  include/linux/hugetlb.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index cccd1aab69dd..c0467a7a1fe0 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -476,6 +476,9 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
>   * huegtlb page specific state flags.  These flags are located in page.private
>   * of the hugetlb head page.  Functions created via the below macros should be
>   * used to manipulate these flags.
> + * Note: The hugetlb page subpool pointer previously located at page.private
> + * was moved to page[1].private to make room for flags in the head page.  See
> + * hugetlb_page_subpool().
>   *
>   * HPG_restore_reserve - Set when a hugetlb page consumes a reservation at
>   *	allocation time.  Cleared when page is fully instantiated.  Free
> -- 
> 2.29.2
> 
> 

-- 
Oscar Salvador
SUSE L3