zsmalloc: remove unused pool param in obj_free

Let's remove unused pool param in obj_free
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/zsmalloc.c

@@ -1438,8 +1438,7 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size)
 }
 EXPORT_SYMBOL_GPL(zs_malloc);
 
-static void obj_free(struct zs_pool *pool, struct size_class *class,
-			unsigned long obj)
+static void obj_free(struct size_class *class, unsigned long obj)
 {
 	struct link_free *link;
 	struct page *first_page, *f_page;
@@ -1485,7 +1484,7 @@ void zs_free(struct zs_pool *pool, unsigned long handle)
 	class = pool->size_class[class_idx];
 
 	spin_lock(&class->lock);
-	obj_free(pool, class, obj);
+	obj_free(class, obj);
 	fullness = fix_fullness_group(class, first_page);
 	if (fullness == ZS_EMPTY) {
 		zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
@@ -1648,7 +1647,7 @@ static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
 		free_obj |= BIT(HANDLE_PIN_BIT);
 		record_obj(handle, free_obj);
 		unpin_tag(handle);
-		obj_free(pool, class, used_obj);
+		obj_free(class, used_obj);
 	}
 
 	/* Remember last position in this iteration */