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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 A8CA1C433DF for ; Sat, 4 Jul 2020 11:35:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 529562084C for ; Sat, 4 Jul 2020 11:35:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 529562084C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 77B2B8D0005; Sat, 4 Jul 2020 07:35:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 72A598D0001; Sat, 4 Jul 2020 07:35:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 63FDD8D0005; Sat, 4 Jul 2020 07:35:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0199.hostedemail.com [216.40.44.199]) by kanga.kvack.org (Postfix) with ESMTP id 4E4BC8D0001 for ; Sat, 4 Jul 2020 07:35:41 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 0D1A3181AC9B6 for ; Sat, 4 Jul 2020 11:35:41 +0000 (UTC) X-FDA: 77000188482.22.beef97_44038c626e9a Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin22.hostedemail.com (Postfix) with ESMTP id D815F18038E60 for ; Sat, 4 Jul 2020 11:35:40 +0000 (UTC) X-HE-Tag: beef97_44038c626e9a X-Filterd-Recvd-Size: 3747 Received: from out4436.biz.mail.alibaba.com (out4436.biz.mail.alibaba.com [47.88.44.36]) by imf01.hostedemail.com (Postfix) with ESMTP for ; Sat, 4 Jul 2020 11:35:39 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=17;SR=0;TI=SMTPD_---0U1eyb8d_1593862524; Received: from IT-FVFX43SYHV2H.lan(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U1eyb8d_1593862524) by smtp.aliyun-inc.com(127.0.0.1); Sat, 04 Jul 2020 19:35:24 +0800 Subject: Re: [PATCH v14 15/20] mm/swap: serialize memcg changes during pagevec_lru_move_fn To: Konstantin Khlebnikov Cc: Andrew Morton , Mel Gorman , Tejun Heo , Hugh Dickins , =?UTF-8?B?0JrQvtC90YHRgtCw0L3RgtC40L0g0KXQu9C10LHQvdC40LrQvtCy?= , daniel.m.jordan@oracle.com, yang.shi@linux.alibaba.com, Matthew Wilcox , Johannes Weiner , lkp@intel.com, linux-mm@kvack.org, Linux Kernel Mailing List , Cgroups , shakeelb@google.com, Joonsoo Kim , richard.weiyang@gmail.com References: <1593752873-4493-1-git-send-email-alex.shi@linux.alibaba.com> <1593752873-4493-16-git-send-email-alex.shi@linux.alibaba.com> From: Alex Shi Message-ID: <56e395c6-81e7-7163-0d4f-42b91573289f@linux.alibaba.com> Date: Sat, 4 Jul 2020 19:34:59 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 X-Rspamd-Queue-Id: D815F18038E60 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 Content-Transfer-Encoding: quoted-printable 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: =E5=9C=A8 2020/7/3 =E4=B8=8B=E5=8D=885:13, Konstantin Khlebnikov =E5=86=99= =E9=81=93: >> @@ -976,7 +983,7 @@ static void __pagevec_lru_add_fn(struct page *page= , struct lruvec *lruvec) >> */ >> void __pagevec_lru_add(struct pagevec *pvec) >> { >> - pagevec_lru_move_fn(pvec, __pagevec_lru_add_fn); >> + pagevec_lru_move_fn(pvec, __pagevec_lru_add_fn, true); >> } > It seems better to open code version in lru_add than adding a bool > argument which is true just for one user. Right, I will rewrite this part as your suggestion. Thanks! >=20 > Also with this new lru protection logic lru_add could be optimized: > It could prepare a list of pages and under lru_lock do only list > splice and bumping counter. > Since PageLRU isn't set yet nobody could touch these pages in lru. > After that lru_add could iterate pages from first to last without > lru_lock to set PageLRU and drop reference. >=20 > So, lru_add will do O(1) operations under lru_lock regardless of the > count of pages it added. >=20 > Actually per-cpu vector for adding could be replaced with per-cpu > lists and\or per-lruvec atomic slist. > Thus incommig pages will be already in list structure rather than page = vector. > This allows to accumulate more pages and offload adding to kswapd or > direct reclaim. >=20 That's a great idea! Guess what the new struct we need would be like this= ? I like to try this. :) diff --git a/include/linux/pagevec.h b/include/linux/pagevec.h index 081d934eda64..d62778c8c184 100644 --- a/include/linux/pagevec.h +++ b/include/linux/pagevec.h @@ -20,7 +20,7 @@ struct pagevec { unsigned char nr; bool percpu_pvec_drained; - struct page *pages[PAGEVEC_SIZE]; + struct list_head veclist; };