[PATCH 1/3] mm/swapfile.c: remove __has_usable_swap()

[Baoquan He <bhe@redhat.com>]

Global total_swap_pages can indicate if usable swap deivice is present,
use it instead of __has_usable_swap().

Signed-off-by: Baoquan He <bhe@redhat.com>
---
 mm/swapfile.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 2bd8bd76ea28..5d71c748a2fe 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -3836,11 +3836,6 @@ static void free_swap_count_continuations(struct swap_info_struct *si)
 }
 
 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
-static bool __has_usable_swap(void)
-{
-	return !plist_head_empty(&swap_active_head);
-}
-
 void __folio_throttle_swaprate(struct folio *folio, gfp_t gfp)
 {
 	struct swap_info_struct *si, *next;
@@ -3848,7 +3843,7 @@ void __folio_throttle_swaprate(struct folio *folio, gfp_t gfp)
 	if (!(gfp & __GFP_IO))
 		return;
 
-	if (!__has_usable_swap())
+	if (!total_swap_pages)
 		return;
 
 	if (!blk_cgroup_congested())
-- 
2.41.0