Re: [RFC linux-next PATCH] mm: khugepaged: remove error message when checking external pins

[Yang Shi]

On 5/21/20 7:56 AM, Qian Cai wrote:
> On Wed, May 13, 2020 at 05:03:03AM +0800, Yang Shi wrote:
> []
> >   mm/khugepaged.c | 24 +++++++++++++++++-------
> >   1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> > index 1fdd677..048f5d4 100644
> > --- a/mm/khugepaged.c
> > +++ b/mm/khugepaged.c
> > @@ -602,12 +602,6 @@ static bool is_refcount_suitable(struct page *page)
> >   	if (PageSwapCache(page))
> >   		expected_refcount += compound_nr(page);
> >   
> > -	if (IS_ENABLED(CONFIG_DEBUG_VM) && expected_refcount > refcount) {
> > -		pr_err("expected_refcount (%d) > refcount (%d)\n",
> > -				expected_refcount, refcount);
> > -		dump_page(page, "Unexpected refcount");
> > -	}
> > -
> >   	return page_count(page) == expected_refcount;
> >   }
> mm/khugepaged.c: In function 'is_refcount_suitable':
> mm/khugepaged.c:575:25: warning: variable 'refcount set but not used [-Wunused-but-set-variable]
>    int expected_refcount, refcount;
>                           ^~~~~~~~
>
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -572,9 +572,8 @@ static void release_pte_pages(pte_t *pte, pte_t *_pte,
>   
>   static bool is_refcount_suitable(struct page *page)
>   {
> -	int expected_refcount, refcount;
> +	int expected_refcount;
>   
> -	refcount = page_count(page);
>   	expected_refcount = total_mapcount(page);
>   	if (PageSwapCache(page))
>   		expected_refcount += compound_nr(page);

Thanks for catching this.