Re: [PATCH 3/3 -mmotm-2009-12-10-17-19] Fix wrong rss counting of smap

[Minchan Kim <minchan.kim@gmail.com>]

I missed Hugn and Matt. 

Minchan Kim wrote:
> After return zero_page, vm_normal_page can return
> NULL if the page is zero page.
> 
> In such case, RSS and PSS can be mismatched.
> This patch fixes it.
> 
> Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
> ---
>  fs/proc/task_mmu.c |    5 ++---
>  1 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
> index 47c03f4..1a47be9 100644
> --- a/fs/proc/task_mmu.c
> +++ b/fs/proc/task_mmu.c
> @@ -361,12 +361,11 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
>  		if (!pte_present(ptent))
>  			continue;
>  
> -		mss->resident += PAGE_SIZE;
> -
>  		page = vm_normal_page(vma, addr, ptent);
> -		if (!page)
> +		if (!page && !is_zero_pfn(pte_pfn(ptent)))
>  			continue;
>  
> +		mss->resident += PAGE_SIZE;
>  		/* Accumulate the size in pages that have been accessed. */
>  		if (pte_young(ptent) || PageReferenced(page))
>  			mss->referenced += PAGE_SIZE;