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

[Qian Cai <cai@lca.pw>]

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);