From patchwork Thu Sep 24 03:28:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Shi X-Patchwork-Id: 11796013 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 10F5292C for ; Thu, 24 Sep 2020 03:29:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C113823600 for ; Thu, 24 Sep 2020 03:29:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C113823600 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 5DC97900011; Wed, 23 Sep 2020 23:28:59 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 5173C90000A; Wed, 23 Sep 2020 23:28:59 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3BD2B900011; Wed, 23 Sep 2020 23:28:59 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0087.hostedemail.com [216.40.44.87]) by kanga.kvack.org (Postfix) with ESMTP id 2260D90000A for ; Wed, 23 Sep 2020 23:28:59 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id D7D271E08 for ; Thu, 24 Sep 2020 03:28:58 +0000 (UTC) X-FDA: 77296523556.07.jeans98_4a12d392715b Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin07.hostedemail.com (Postfix) with ESMTP id BE0C81803FF14 for ; Thu, 24 Sep 2020 03:28:58 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,alex.shi@linux.alibaba.com,,RULES_HIT:30054:30070,0,RBL:47.88.44.36:@linux.alibaba.com:.lbl8.mailshell.net-64.10.201.10 62.18.0.100;04yg34ri5da9kfx9ma4qgzujx3q3qoccrzb5e146pqnasz544dsuegsjo6m6trb.p7nb8w3m9iwrfn6rjnmzyzbexfeuoykanhxde156d8oxx4g6dmquu6ry7d934fy.y-lbl8.mailshell.net-223.238.255.100;47.88.44.36-irl.urbl.hostedemail.com-127.0.0.175,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: jeans98_4a12d392715b X-Filterd-Recvd-Size: 6300 Received: from out4436.biz.mail.alibaba.com (out4436.biz.mail.alibaba.com [47.88.44.36]) by imf29.hostedemail.com (Postfix) with ESMTP for ; Thu, 24 Sep 2020 03:28:57 +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=e01e04395;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=22;SR=0;TI=SMTPD_---0U9w0Ss1_1600918116; Received: from aliy80.localdomain(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U9w0Ss1_1600918116) by smtp.aliyun-inc.com(127.0.0.1); Thu, 24 Sep 2020 11:28:44 +0800 From: Alex Shi To: akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, willy@infradead.org, hannes@cmpxchg.org, lkp@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, shakeelb@google.com, iamjoonsoo.kim@lge.com, richard.weiyang@gmail.com, kirill@shutemov.name, alexander.duyck@gmail.com, rong.a.chen@intel.com, mhocko@suse.com, vdavydov.dev@gmail.com, shy828301@gmail.com, aaron.lwe@gmail.com Subject: [PATCH v19 17/20] mm/swap.c: serialize memcg changes in pagevec_lru_move_fn Date: Thu, 24 Sep 2020 11:28:32 +0800 Message-Id: <1600918115-22007-18-git-send-email-alex.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1600918115-22007-1-git-send-email-alex.shi@linux.alibaba.com> References: <1600918115-22007-1-git-send-email-alex.shi@linux.alibaba.com> 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: Hugh Dickins' found a memcg change bug on original version: If we want to change the pgdat->lru_lock to memcg's lruvec lock, we have to serialize mem_cgroup_move_account during pagevec_lru_move_fn. The possible bad scenario would like: cpu 0 cpu 1 lruvec = mem_cgroup_page_lruvec() if (!isolate_lru_page()) mem_cgroup_move_account spin_lock_irqsave(&lruvec->lru_lock <== wrong lock. So we need TestClearPageLRU to block isolate_lru_page(), that serializes the memcg change. and then removing the PageLRU check in move_fn callee as the consequence. __pagevec_lru_add_fn() is different from the others, because the pages it deals with are, by definition, not yet on the lru. TestClearPageLRU is not needed and would not work, so __pagevec_lru_add() goes its own way. Reported-by: Hugh Dickins Signed-off-by: Alex Shi Acked-by: Hugh Dickins Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- mm/swap.c | 44 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 35 insertions(+), 9 deletions(-) diff --git a/mm/swap.c b/mm/swap.c index 6a4b00267384..50418dcc5e24 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -222,8 +222,14 @@ static void pagevec_lru_move_fn(struct pagevec *pvec, spin_lock_irqsave(&pgdat->lru_lock, flags); } + /* block memcg migration during page moving between lru */ + if (!TestClearPageLRU(page)) + continue; + lruvec = mem_cgroup_page_lruvec(page, pgdat); (*move_fn)(page, lruvec); + + SetPageLRU(page); } if (pgdat) spin_unlock_irqrestore(&pgdat->lru_lock, flags); @@ -233,7 +239,7 @@ static void pagevec_lru_move_fn(struct pagevec *pvec, static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec) { - if (PageLRU(page) && !PageUnevictable(page)) { + if (!PageUnevictable(page)) { del_page_from_lru_list(page, lruvec, page_lru(page)); ClearPageActive(page); add_page_to_lru_list_tail(page, lruvec, page_lru(page)); @@ -306,7 +312,7 @@ void lru_note_cost_page(struct page *page) static void __activate_page(struct page *page, struct lruvec *lruvec) { - if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) { + if (!PageActive(page) && !PageUnevictable(page)) { int lru = page_lru_base_type(page); int nr_pages = thp_nr_pages(page); @@ -362,7 +368,8 @@ void activate_page(struct page *page) page = compound_head(page); spin_lock_irq(&pgdat->lru_lock); - __activate_page(page, mem_cgroup_page_lruvec(page, pgdat)); + if (PageLRU(page)) + __activate_page(page, mem_cgroup_page_lruvec(page, pgdat)); spin_unlock_irq(&pgdat->lru_lock); } #endif @@ -521,9 +528,6 @@ static void lru_deactivate_file_fn(struct page *page, struct lruvec *lruvec) bool active; int nr_pages = thp_nr_pages(page); - if (!PageLRU(page)) - return; - if (PageUnevictable(page)) return; @@ -564,7 +568,7 @@ static void lru_deactivate_file_fn(struct page *page, struct lruvec *lruvec) static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec) { - if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) { + if (PageActive(page) && !PageUnevictable(page)) { int lru = page_lru_base_type(page); int nr_pages = thp_nr_pages(page); @@ -581,7 +585,7 @@ static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec) static void lru_lazyfree_fn(struct page *page, struct lruvec *lruvec) { - if (PageLRU(page) && PageAnon(page) && PageSwapBacked(page) && + if (PageAnon(page) && PageSwapBacked(page) && !PageSwapCache(page) && !PageUnevictable(page)) { bool active = PageActive(page); int nr_pages = thp_nr_pages(page); @@ -979,7 +983,29 @@ 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); + int i; + struct pglist_data *pgdat = NULL; + struct lruvec *lruvec; + unsigned long flags = 0; + + for (i = 0; i < pagevec_count(pvec); i++) { + struct page *page = pvec->pages[i]; + struct pglist_data *pagepgdat = page_pgdat(page); + + if (pagepgdat != pgdat) { + if (pgdat) + spin_unlock_irqrestore(&pgdat->lru_lock, flags); + pgdat = pagepgdat; + spin_lock_irqsave(&pgdat->lru_lock, flags); + } + + lruvec = mem_cgroup_page_lruvec(page, pgdat); + __pagevec_lru_add_fn(page, lruvec); + } + if (pgdat) + spin_unlock_irqrestore(&pgdat->lru_lock, flags); + release_pages(pvec->pages, pvec->nr); + pagevec_reinit(pvec); } /**