On Mon, Jan 13, 2020 at 08:44:57AM +0800, Wei Yang wrote: > >> It is possible two page in the same pgdate or memcg grab page lock > >> respectively and then access the same defer queue concurrently. > > If my understanding is correct, you agree with my statement? Which one? If the one above then no. list_empty only accesses list_head for the struct page, not the queue. -- Kirill A. Shutemov