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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT 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 43CD7C433E1 for ; Mon, 24 Aug 2020 12:56:34 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0675D20706 for ; Mon, 24 Aug 2020 12:56:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0675D20706 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 5461C8D0018; Mon, 24 Aug 2020 08:55:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 361988D001C; Mon, 24 Aug 2020 08:55:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 115FB8D001A; Mon, 24 Aug 2020 08:55:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0063.hostedemail.com [216.40.44.63]) by kanga.kvack.org (Postfix) with ESMTP id D4D688D0018 for ; Mon, 24 Aug 2020 08:55:39 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 7196E3629 for ; Mon, 24 Aug 2020 12:55:39 +0000 (UTC) X-FDA: 77185458798.25.tin24_470693127053 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id CB3C71804E3A0 for ; Mon, 24 Aug 2020 12:55:38 +0000 (UTC) X-HE-Tag: tin24_470693127053 X-Filterd-Recvd-Size: 5162 Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com [115.124.30.130]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Mon, 24 Aug 2020 12:55:36 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R621e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04392;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=23;SR=0;TI=SMTPD_---0U6k9-bl_1598273712; Received: from aliy80.localdomain(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U6k9-bl_1598273712) by smtp.aliyun-inc.com(127.0.0.1); Mon, 24 Aug 2020 20:55:22 +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 Cc: "Kirill A. Shutemov" , Vlastimil Babka Subject: [PATCH v18 25/32] mm/mlock: remove lru_lock on TestClearPageMlocked in munlock_vma_page Date: Mon, 24 Aug 2020 20:54:58 +0800 Message-Id: <1598273705-69124-26-git-send-email-alex.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1598273705-69124-1-git-send-email-alex.shi@linux.alibaba.com> References: <1598273705-69124-1-git-send-email-alex.shi@linux.alibaba.com> X-Rspamd-Queue-Id: CB3C71804E3A0 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 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: In the func munlock_vma_page, the page must be PageLocked as well as pages in split_huge_page series funcs. Thus the PageLocked is enough to serialize both funcs. So we could relief the TestClearPageMlocked/hpage_nr_pages which are not necessary under lru lock. As to another munlock func __munlock_pagevec, which no PageLocked protection and should remain lru protecting. Signed-off-by: Alex Shi Cc: Kirill A. Shutemov Cc: Vlastimil Babka Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- mm/mlock.c | 41 +++++++++++++++-------------------------- 1 file changed, 15 insertions(+), 26 deletions(-) diff --git a/mm/mlock.c b/mm/mlock.c index 0448409184e3..46a05e6ec5ba 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -69,9 +69,9 @@ void clear_page_mlock(struct page *page) * * See __pagevec_lru_add_fn for more explanation. */ - if (!isolate_lru_page(page)) { + if (!isolate_lru_page(page)) putback_lru_page(page); - } else { + else { /* * We lost the race. the page already moved to evictable list. */ @@ -178,7 +178,6 @@ static void __munlock_isolation_failed(struct page *page) unsigned int munlock_vma_page(struct page *page) { int nr_pages; - struct lruvec *lruvec; /* For try_to_munlock() and to serialize with page migration */ BUG_ON(!PageLocked(page)); @@ -186,37 +185,22 @@ unsigned int munlock_vma_page(struct page *page) VM_BUG_ON_PAGE(PageTail(page), page); /* - * Serialize split tail pages in __split_huge_page_tail() which - * might otherwise copy PageMlocked to part of the tail pages before - * we clear it in the head page. It also stabilizes thp_nr_pages(). - * TestClearPageLRU can't be used here to block page isolation, since - * out of lock clear_page_mlock may interfer PageLRU/PageMlocked - * sequence, same as __pagevec_lru_add_fn, and lead the page place to - * wrong lru list here. So relay on PageLocked to stop lruvec change - * in mem_cgroup_move_account(). + * Serialize split tail pages in __split_huge_page_tail() by + * lock_page(); Do TestClearPageMlocked/PageLRU sequence like + * clear_page_mlock(). */ - lruvec = lock_page_lruvec_irq(page); - - if (!TestClearPageMlocked(page)) { + if (!TestClearPageMlocked(page)) /* Potentially, PTE-mapped THP: do not skip the rest PTEs */ - nr_pages = 1; - goto unlock_out; - } + return 0; nr_pages = thp_nr_pages(page); __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages); - if (__munlock_isolate_lru_page(page, lruvec, true)) { - unlock_page_lruvec_irq(lruvec); + if (!isolate_lru_page(page)) __munlock_isolated_page(page); - goto out; - } - __munlock_isolation_failed(page); - -unlock_out: - unlock_page_lruvec_irq(lruvec); + else + __munlock_isolation_failed(page); -out: return nr_pages - 1; } @@ -305,6 +289,11 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) /* block memcg change in mem_cgroup_move_account */ lock_page_memcg(page); + /* + * Serialize split tail pages in __split_huge_page_tail() which + * might otherwise copy PageMlocked to part of the tail pages + * before we clear it in the head page. + */ lruvec = relock_page_lruvec_irq(page, lruvec); if (TestClearPageMlocked(page)) { /* -- 1.8.3.1