[RFC PATCH v3 15/21] mm/zsmalloc: convert __free_zspage() to use zsdesc

[Hyeonggon Yoo <42.hyeyoo@gmail.com>]

Introduce zsdesc_is_locked() and convert __free_zspage() to use zsdesc.

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
---
 mm/zsmalloc.c | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 92641a3b2d98..fdcc47569644 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -317,6 +317,11 @@ static inline void unlock_zsdesc(struct zsdesc *zsdesc)
 	unlock_page(zsdesc_page(zsdesc));
 }
 
+static inline bool zsdesc_is_locked(struct zsdesc *zsdesc)
+{
+	return PageLocked(zsdesc_page(zsdesc));
+}
+
 static inline void wait_on_zsdesc_locked(struct zsdesc *zsdesc)
 {
 	wait_on_page_locked(zsdesc_page(zsdesc));
@@ -1011,7 +1016,7 @@ static int trylock_zspage(struct zspage *zspage)
 static void __free_zspage(struct zs_pool *pool, struct size_class *class,
 				struct zspage *zspage)
 {
-	struct page *page, *next;
+	struct zsdesc *zsdesc, *next;
 	int fg;
 	unsigned int class_idx;
 
@@ -1022,16 +1027,16 @@ static void __free_zspage(struct zs_pool *pool, struct size_class *class,
 	VM_BUG_ON(get_zspage_inuse(zspage));
 	VM_BUG_ON(fg != ZS_INUSE_RATIO_0);
 
-	next = page = get_first_page(zspage);
+	next = zsdesc = get_first_zsdesc(zspage);
 	do {
-		VM_BUG_ON_PAGE(!PageLocked(page), page);
-		next = get_next_page(page);
-		reset_zsdesc(page_zsdesc(page));
-		unlock_page(page);
-		dec_zone_page_state(page, NR_ZSPAGES);
-		put_page(page);
-		page = next;
-	} while (page != NULL);
+		VM_BUG_ON_PAGE(!zsdesc_is_locked(zsdesc), zsdesc_page(zsdesc));
+		next = get_next_zsdesc(zsdesc);
+		reset_zsdesc(zsdesc);
+		unlock_zsdesc(zsdesc);
+		zsdesc_dec_zone_page_state(zsdesc);
+		zsdesc_put(zsdesc);
+		zsdesc = next;
+	} while (zsdesc != NULL);
 
 	cache_free_zspage(pool, zspage);
 
-- 
2.39.3