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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 B7450C432C0 for ; Sun, 1 Dec 2019 01:57:18 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7866E205ED for ; Sun, 1 Dec 2019 01:57:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="O6MRrFdF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7866E205ED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 1FD276B036E; Sat, 30 Nov 2019 20:57:18 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1D5BC6B0370; Sat, 30 Nov 2019 20:57:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 09D5B6B0371; Sat, 30 Nov 2019 20:57:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0054.hostedemail.com [216.40.44.54]) by kanga.kvack.org (Postfix) with ESMTP id E46706B036E for ; Sat, 30 Nov 2019 20:57:17 -0500 (EST) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id 998EA180AD817 for ; Sun, 1 Dec 2019 01:57:17 +0000 (UTC) X-FDA: 76214910114.25.time65_3fa6390f1731b X-HE-Tag: time65_3fa6390f1731b X-Filterd-Recvd-Size: 3029 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Sun, 1 Dec 2019 01:57:17 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E5FEA20873; Sun, 1 Dec 2019 01:57:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575165436; bh=GkZ0k2Q12lDqrJYbxGBpJ394Oqy+QeZOEOYWxn8aoMo=; h=Date:From:To:Subject:From; b=O6MRrFdF6R+06GtgZ+oD2pIVxgpPNHTUXQoEw4xzeNa3WejHcboGZEtomHEHic9RU qiUxDZXaEgx+GHkVoOxQcJNWp4K4ZJ5JI9XgFXlypgslPpgX9KxDq2rEMb8f/VSG1X JOYo+ZV3W50wX1WTQPyuJQfAiN4fH5uP1wlS/WCU= Date: Sat, 30 Nov 2019 17:57:15 -0800 From: akpm@linux-foundation.org To: akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, kirill@shutemov.name, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, yang.shi@linux.alibaba.com Subject: [patch 135/158] mm, thp: do not queue fully unmapped pages for deferred split Message-ID: <20191201015715.7Go-jCWUJ%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "Kirill A. Shutemov" Subject: mm, thp: do not queue fully unmapped pages for deferred split Adding fully unmapped pages into deferred split queue is not productive: these pages are about to be freed or they are pinned and cannot be split anyway. Link: http://lkml.kernel.org/r/20190913091849.11151-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Reviewed-by: Yang Shi Cc: Michal Hocko Signed-off-by: Andrew Morton --- mm/rmap.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/mm/rmap.c~mm-thp-do-not-queue-fully-unmapped-pages-for-deferred-split +++ a/mm/rmap.c @@ -1292,12 +1292,20 @@ static void page_remove_anon_compound_rm if (TestClearPageDoubleMap(page)) { /* * Subpages can be mapped with PTEs too. Check how many of - * themi are still mapped. + * them are still mapped. */ for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { if (atomic_add_negative(-1, &page[i]._mapcount)) nr++; } + + /* + * Queue the page for deferred split if at least one small + * page of the compound page is unmapped, but at least one + * small page is still mapped. + */ + if (nr && nr < HPAGE_PMD_NR) + deferred_split_huge_page(page); } else { nr = HPAGE_PMD_NR; } @@ -1305,10 +1313,8 @@ static void page_remove_anon_compound_rm if (unlikely(PageMlocked(page))) clear_page_mlock(page); - if (nr) { + if (nr) __mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, -nr); - deferred_split_huge_page(page); - } } /** _