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=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 26B09C43331 for ; Fri, 3 Apr 2020 13:12:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C07AF2077D for ; Fri, 3 Apr 2020 13:12:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="OXm404pl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C07AF2077D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 43BD78E0009; Fri, 3 Apr 2020 09:12:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 411FD8E0007; Fri, 3 Apr 2020 09:12:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 300C28E0009; Fri, 3 Apr 2020 09:12:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0115.hostedemail.com [216.40.44.115]) by kanga.kvack.org (Postfix) with ESMTP id 1489E8E0007 for ; Fri, 3 Apr 2020 09:12:23 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id BEF2E82499B9 for ; Fri, 3 Apr 2020 13:12:22 +0000 (UTC) X-FDA: 76666582524.02.fowl99_4ee949966fb5d X-HE-Tag: fowl99_4ee949966fb5d X-Filterd-Recvd-Size: 5588 Received: from aserp2120.oracle.com (aserp2120.oracle.com [141.146.126.78]) by imf38.hostedemail.com (Postfix) with ESMTP for ; Fri, 3 Apr 2020 13:12:22 +0000 (UTC) Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 033D9eT7168136; Fri, 3 Apr 2020 13:12:19 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=7n+MDhRrbq9TiAJJ1tQrkO6V5YiXNpNCJQJK7RlWz+4=; b=OXm404plt1hUNxb6VAOgMemfBQLkiHpewCmA07AQG9r2c5wETvbE6GSRniCm+pB5g4HN rlzKelYJqyb5HC1ZuM4DHeLMKxfnZ/V5bgNAYup/oSljC0YAwg/9gSm1lGwOuE5XA9F1 3490cS9YME+H2TycIHdniYzYjA9juevwFWbKfgz6FfDeqGgjD97K8XW750U2JeAFEKc/ UfDVJMV7ZK3mK63vev/KbzVEYfDmZ51ODm825M5Vke17D24p+Add2brQresrRe1xljeK gyBjxISmw8oihWnpJw12rIXhBFXXKYtkmG9Kajzl7F31S9CyarW8UMDhcg7HiYu9ZyZF Ow== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 303yunkhve-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 03 Apr 2020 13:12:19 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 033DCETM026091; Fri, 3 Apr 2020 13:12:18 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3020.oracle.com with ESMTP id 302ga4pmav-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 03 Apr 2020 13:12:16 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 033DC141027756; Fri, 3 Apr 2020 13:12:01 GMT Received: from ca-dmjordan1.us.oracle.com (/10.211.9.48) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 03 Apr 2020 06:12:00 -0700 Date: Fri, 3 Apr 2020 09:12:20 -0400 From: Daniel Jordan To: Yang Shi Cc: Daniel Jordan , kirill.shutemov@linux.intel.com, hughd@google.com, aarcange@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: thp: don't need drain lru cache when splitting and mlocking THP Message-ID: <20200403131220.za3wfj6k33whobp7@ca-dmjordan1.us.oracle.com> References: <1585337380-97368-1-git-send-email-yang.shi@linux.alibaba.com> <20200402230411.7ckwkmd6wwtqfkm2@ca-dmjordan1.us.oracle.com> <20200402231731.32imzorzucpj4s6w@ca-dmjordan1.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9579 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 mlxlogscore=639 bulkscore=0 mlxscore=0 spamscore=0 adultscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004030116 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9579 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 lowpriorityscore=0 malwarescore=0 adultscore=0 priorityscore=1501 mlxlogscore=692 bulkscore=0 suspectscore=0 mlxscore=0 spamscore=0 impostorscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004030115 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: On Thu, Apr 02, 2020 at 04:37:06PM -0700, Yang Shi wrote: > > > On 4/2/20 4:17 PM, Daniel Jordan wrote: > > On Thu, Apr 02, 2020 at 07:04:11PM -0400, Daniel Jordan wrote: > > > On Sat, Mar 28, 2020 at 03:29:40AM +0800, Yang Shi wrote: > > > > Since the commit 8f182270dfec ("mm/swap.c: flush lru pvecs on compound > > > > page arrival") THP would not stay in pagevec anymore. So the > > > > optimization made by commit d965432234db ("thp: increase > > > > split_huge_page() success rate") doesn't make sense anymore, which tries > > > > to unpin munlocked THPs from pagevec by draining pagevec. > > > > > > > > And draining lru cache before isolating THP in mlock path is unnecessary > > > > either. > > > Can we get some of that nice history in this part too? > > > > > > Draining lru cache before isolating THP in mlock path is also unnecessary. > > > b676b293fb48 ("mm, thp: fix mapped pages avoiding unevictable list on mlock") > > > added it and 9a73f61bdb8a ("thp, mlock: do not mlock PTE-mapped file huge > > > pages") accidentally carried it over after the above optimization went in. > > > > > > > Cc: Kirill A. Shutemov > > > > Cc: Hugh Dickins > > > > Cc: Andrea Arcangeli > > > > Signed-off-by: Yang Shi > > > Since we don't mlock pte-mapped THP, it seems these huge pages wouldn't ever be > > > in the pagevecs if I'm understanding it all. > > Actually pte-mapped THP doesn't matter for this, both paths always drain when > > they're working with pmd-mapped THP. > > Actually either pte-mapped or pmd-mapped doesn't matter, as long as it is > compound page the lru cache would be flushed immediately upon the arrival of > the compound page. Ah, that's right! The checks in swap.c are for PageCompound.