Instead of moving list elements from destroy_list to &private_destroy_list,
exchange the list heads.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
 
        for (;;) {
                spin_lock(&destroy_lock);
-               list_for_each_entry_safe(mark, next, &destroy_list, destroy_list) {
-                       list_del(&mark->destroy_list);
-                       list_add(&mark->destroy_list, &private_destroy_list);
-               }
+               /* exchange the list head */
+               list_replace_init(&destroy_list, &private_destroy_list);
                spin_unlock(&destroy_lock);
 
                synchronize_srcu(&fsnotify_mark_srcu);