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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 86081C2BB48 for ; Tue, 15 Dec 2020 22:21:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 520BD22D0B for ; Tue, 15 Dec 2020 22:21:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727384AbgLOWVO (ORCPT ); Tue, 15 Dec 2020 17:21:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:44854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728387AbgLOWVL (ORCPT ); Tue, 15 Dec 2020 17:21:11 -0500 Date: Tue, 15 Dec 2020 14:20:29 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1608070830; bh=yVxFEvuUVn3jmENrHzY0uWR+ELpuL33DI8lqyXbACNI=; h=From:To:Subject:In-Reply-To:From; b=XjOnFjm8+p2j6VOU1qJ6GrWhqu/LB36bxRxSbdene1EaecS11Xj1utHM14g/pCjd0 /A+K81UMEvO/VQWvrqTjsR8Wq/fjadwq9+PDeuqVSJLeT2X/ZFDRW/UDuoSJLjN8Lz 8ezoORUZrY8XbYxlAB33EZ5beBiJrx9IIZVdhMtM= From: Andrew Morton To: aarcange@redhat.com, akpm@linux-foundation.org, alex.shi@linux.alibaba.com, alexander.duyck@gmail.com, aryabinin@virtuozzo.com, daniel.m.jordan@oracle.com, hannes@cmpxchg.org, hughd@google.com, iamjoonsoo.kim@lge.com, jannh@google.com, khlebnikov@yandex-team.ru, kirill.shutemov@linux.intel.com, kirill@shutemov.name, linux-mm@kvack.org, mgorman@techsingularity.net, mhocko@kernel.org, mhocko@suse.com, mika.penttila@nextfour.com, minchan@kernel.org, mm-commits@vger.kernel.org, richard.weiyang@gmail.com, rong.a.chen@intel.com, shakeelb@google.com, tglx@linutronix.de, tj@kernel.org, torvalds@linux-foundation.org, vbabka@suse.cz, vdavydov.dev@gmail.com, willy@infradead.org, yang.shi@linux.alibaba.com, ying.huang@intel.com Subject: [patch 05/19] mm/vmscan: remove unnecessary lruvec adding Message-ID: <20201215222029.OaXVyHWeX%akpm@linux-foundation.org> In-Reply-To: <20201215123253.954eca9a5ef4c0d52fd381fa@linux-foundation.org> User-Agent: s-nail v14.8.16 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org =46rom: Alex Shi Subject: mm/vmscan: remove unnecessary lruvec adding We don't have to add a freeable page into lru and then remove from it.=20 This change saves a couple of actions and makes the moving more clear. The SetPageLRU needs to be kept before put_page_testzero for list integrity, otherwise: #0 move_pages_to_lru #1 release_pages if !put_page_testzero if (put_page_testzero()) !PageLRU //skip lru_lock SetPageLRU() list_add(&page->lru,) list_add(&page->lru,) [akpm@linux-foundation.org: coding style fixes] Link: https://lkml.kernel.org/r/1604566549-62481-6-git-send-email-alex.shi@= linux.alibaba.com Signed-off-by: Alex Shi Acked-by: Hugh Dickins Acked-by: Johannes Weiner Acked-by: Vlastimil Babka Cc: Tejun Heo Cc: Matthew Wilcox Cc: Alexander Duyck Cc: Andrea Arcangeli Cc: Andrey Ryabinin Cc: "Chen, Rong A" Cc: Daniel Jordan Cc: "Huang, Ying" Cc: Jann Horn Cc: Joonsoo Kim Cc: Kirill A. Shutemov Cc: Kirill A. Shutemov Cc: Konstantin Khlebnikov Cc: Mel Gorman Cc: Michal Hocko Cc: Michal Hocko Cc: Mika Penttil=C3=A4 Cc: Minchan Kim Cc: Shakeel Butt Cc: Thomas Gleixner Cc: Vladimir Davydov Cc: Wei Yang Cc: Yang Shi Signed-off-by: Andrew Morton --- mm/vmscan.c | 38 +++++++++++++++++++++++++------------- 1 file changed, 25 insertions(+), 13 deletions(-) --- a/mm/vmscan.c~mm-vmscan-remove-unnecessary-lruvec-adding +++ a/mm/vmscan.c @@ -1851,26 +1851,30 @@ static unsigned noinline_for_stack move_ while (!list_empty(list)) { page =3D lru_to_page(list); VM_BUG_ON_PAGE(PageLRU(page), page); + list_del(&page->lru); if (unlikely(!page_evictable(page))) { - list_del(&page->lru); spin_unlock_irq(&pgdat->lru_lock); putback_lru_page(page); spin_lock_irq(&pgdat->lru_lock); continue; } - lruvec =3D mem_cgroup_page_lruvec(page, pgdat); =20 + /* + * The SetPageLRU needs to be kept here for list integrity. + * Otherwise: + * #0 move_pages_to_lru #1 release_pages + * if !put_page_testzero + * if (put_page_testzero()) + * !PageLRU //skip lru_lock + * SetPageLRU() + * list_add(&page->lru,) + * list_add(&page->lru,) + */ SetPageLRU(page); - lru =3D page_lru(page); =20 - nr_pages =3D thp_nr_pages(page); - update_lru_size(lruvec, lru, page_zonenum(page), nr_pages); - list_move(&page->lru, &lruvec->lists[lru]); - - if (put_page_testzero(page)) { + if (unlikely(put_page_testzero(page))) { __ClearPageLRU(page); __ClearPageActive(page); - del_page_from_lru_list(page, lruvec, lru); =20 if (unlikely(PageCompound(page))) { spin_unlock_irq(&pgdat->lru_lock); @@ -1878,11 +1882,19 @@ static unsigned noinline_for_stack move_ spin_lock_irq(&pgdat->lru_lock); } else list_add(&page->lru, &pages_to_free); - } else { - nr_moved +=3D nr_pages; - if (PageActive(page)) - workingset_age_nonresident(lruvec, nr_pages); + + continue; } + + lruvec =3D mem_cgroup_page_lruvec(page, pgdat); + lru =3D page_lru(page); + nr_pages =3D thp_nr_pages(page); + + update_lru_size(lruvec, lru, page_zonenum(page), nr_pages); + list_add(&page->lru, &lruvec->lists[lru]); + nr_moved +=3D nr_pages; + if (PageActive(page)) + workingset_age_nonresident(lruvec, nr_pages); } =20 /* _