Re: [PATCH] mm: Fix buddy list helpers

[Michal Hocko]

On Sat 16-02-19 09:07:02, Dan Williams wrote:
> Tetsuo reports that free page statistics are not reporting correctly,
> and Vlastimil noticed that "mm: Move buddy list manipulations into
> helpers" botched one of its conversions of add_to_free_area(). Fix the
> double-increment of ->nr_free.
> 
> Reported-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> Reported-by: Vlastimil Babka <vbabka@xxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Tested-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>

Thanks for catching that. I have really missed it during review.
Sorry about that.

Acked-by: Michal Hocko <mhocko@xxxxxxxx>

> ---
> Hi Andrew,
> 
> Please fold this into
> mm-move-buddy-list-manipulations-into-helpers.patch.
> 
>  mm/page_alloc.c |    1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 2a0969e3b0eb..da537fc39c54 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -1851,7 +1851,6 @@ static inline void expand(struct zone *zone, struct page *page,
>  			continue;
>  
>  		add_to_free_area(&page[size], area, migratetype);
> -		area->nr_free++;
>  		set_page_order(&page[size], high);
>  	}
>  }
> 

-- 
Michal Hocko
SUSE Labs