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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C3335C2BA19 for ; Wed, 15 Apr 2020 20:33:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9EB5820774 for ; Wed, 15 Apr 2020 20:33:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S371274AbgDOUdS (ORCPT ); Wed, 15 Apr 2020 16:33:18 -0400 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:54640 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S371258AbgDOUdI (ORCPT ); Wed, 15 Apr 2020 16:33:08 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01419;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=9;SR=0;TI=SMTPD_---0TvdsLqm_1586982783; Received: from US-143344MP.local(mailfrom:yang.shi@linux.alibaba.com fp:SMTPD_---0TvdsLqm_1586982783) by smtp.aliyun-inc.com(127.0.0.1); Thu, 16 Apr 2020 04:33:05 +0800 Subject: Re: [PATCHv3, RESEND 4/8] khugepaged: Drain LRU add pagevec after swapin To: "Kirill A. Shutemov" , akpm@linux-foundation.org, Andrea Arcangeli Cc: Zi Yan , Ralph Campbell , John Hubbard , William Kucharski , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20200413125220.663-1-kirill.shutemov@linux.intel.com> <20200413125220.663-5-kirill.shutemov@linux.intel.com> From: Yang Shi Message-ID: <602d9624-1a41-611f-bba9-f38806be9c33@linux.alibaba.com> Date: Wed, 15 Apr 2020 13:32:59 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20200413125220.663-5-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/13/20 5:52 AM, Kirill A. Shutemov wrote: > __collapse_huge_page_isolate() may fail due to extra pin in the LRU add > pagevec. It's pretty common for swapin case: we swap in pages just to > fail due to the extra pin. > > Drain LRU add pagevec on successful swapin. > > Signed-off-by: Kirill A. Shutemov > --- > mm/khugepaged.c | 5 +++++ > 1 file changed, 5 insertions(+) Acked-by: Yang Shi > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index ee66c140c2d6..e3e41c2768d8 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -934,6 +934,11 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, > } > vmf.pte--; > pte_unmap(vmf.pte); > + > + /* Drain LRU add pagevec to remove extra pin on the swapped in pages */ > + if (swapped_in) > + lru_add_drain(); > + > trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 1); > return true; > }