From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BADC5C433E2 for ; Fri, 4 Sep 2020 10:50:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8F81D20770 for ; Fri, 4 Sep 2020 10:50:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729883AbgIDKuF (ORCPT ); Fri, 4 Sep 2020 06:50:05 -0400 Received: from mx2.suse.de ([195.135.220.15]:35900 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726811AbgIDKuD (ORCPT ); Fri, 4 Sep 2020 06:50:03 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 7B96EAED8; Fri, 4 Sep 2020 10:50:03 +0000 (UTC) Date: Fri, 4 Sep 2020 12:50:01 +0200 From: Michal Hocko To: Yu Zhao Cc: Andrew Morton , Alex Shi , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/2] mm: use add_page_to_lru_list()/page_lru()/page_off_lru() Message-ID: <20200904105001.GH15277@dhcp22.suse.cz> References: <20200831175042.3527153-1-yuzhao@google.com> <20200903082832.GR4617@dhcp22.suse.cz> <20200904032400.GA4102421@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200904032400.GA4102421@google.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 03-09-20 21:24:00, Yu Zhao wrote: > On Thu, Sep 03, 2020 at 10:28:32AM +0200, Michal Hocko wrote: > > On Mon 31-08-20 11:50:41, Yu Zhao wrote: > > [...] > > > @@ -1860,16 +1859,11 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, > > > lruvec = mem_cgroup_page_lruvec(page, pgdat); > > > > > > SetPageLRU(page); > > > - lru = page_lru(page); > > > - > > > - nr_pages = thp_nr_pages(page); > > > - update_lru_size(lruvec, lru, page_zonenum(page), nr_pages); > > > - list_move(&page->lru, &lruvec->lists[lru]); > > > + add_page_to_lru_list(page, lruvec, page_lru(page)); > > > > > > if (put_page_testzero(page)) { > > > __ClearPageLRU(page); > > > - __ClearPageActive(page); > > > > This should go into its own patch. The rest is a mechanical and clear. > > Thanks for reviewing. > > I assume you are worrying about PG_unevictable being set on the page > because page_off_lru() checks it first. No, I was referring to __ClearPageActive. You are right that this is cleared in page_off_lru but that is hidden in a release path and e.g. compound pages are released via their destructor which for some might not involve releasing the page - e.g. hugetlb pages. This should be fine because hugetlb pages are not on LRU so as I've said this is fine but it belongs to its own patch because it is not a pure mechanical change like the rest of the patch. -- Michal Hocko SUSE Labs