From patchwork Sat Jul 11 00:58:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Shi X-Patchwork-Id: 11657623 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 C355013B1 for ; Sat, 11 Jul 2020 00:59:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9A0952076A for ; Sat, 11 Jul 2020 00:59:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A0952076A 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 05C218D000F; Fri, 10 Jul 2020 20:59:16 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id F07498D0010; Fri, 10 Jul 2020 20:59:15 -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 CBCE38D0013; Fri, 10 Jul 2020 20:59:15 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0227.hostedemail.com [216.40.44.227]) by kanga.kvack.org (Postfix) with ESMTP id 8E16F8D0010 for ; Fri, 10 Jul 2020 20:59:15 -0400 (EDT) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 56548180AD801 for ; Sat, 11 Jul 2020 00:59:15 +0000 (UTC) X-FDA: 77023986270.12.owner87_1b1758526ed2 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin12.hostedemail.com (Postfix) with ESMTP id 299BD1800A67B for ; Sat, 11 Jul 2020 00:59:15 +0000 (UTC) X-Spam-Summary: 1,0,0,37486f1c1d331d6a,d41d8cd98f00b204,alex.shi@linux.alibaba.com,,RULES_HIT:2:41:69:355:379:541:560:800:960:968:973:988:989:1260:1261:1345:1359:1381:1431:1437:1535:1605:1606:1730:1747:1777:1792:2198:2199:2393:2559:2562:2693:2898:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3872:3874:4117:4250:4321:5007:6261:6737:8957:9592:11026:11473:11658:11914:12043:12048:12291:12296:12297:12438:12555:12683:12895:12986:13846:14394:14915:21060:21080:21451:21627:21987:21990:30054:30064:30070:30079,0,RBL:115.124.30.131:@linux.alibaba.com:.lbl8.mailshell.net-64.201.201.201 62.20.2.100;04y8jdk9u4ficsbpn8enmodegyreyoc1jjcjsjao7synparn387rars13fdfbjn.7fxo3cj67q1srek7o7eoqdtdiu9c5d34m6nh9w3r19hugek1tt8m9x6qgr5q9ox.c-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:2:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: owner87_1b1758526ed2 X-Filterd-Recvd-Size: 6938 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) by imf18.hostedemail.com (Postfix) with ESMTP for ; Sat, 11 Jul 2020 00:59:13 +0000 (UTC) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R451e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01422;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=17;SR=0;TI=SMTPD_---0U2KGAZr_1594429139; Received: from alexshi-test.localdomain(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U2KGAZr_1594429139) by smtp.aliyun-inc.com(127.0.0.1); Sat, 11 Jul 2020 08:59:06 +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, yang.shi@linux.alibaba.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 Subject: [PATCH v16 16/22] mm/mlock: reorder isolation sequence during munlock Date: Sat, 11 Jul 2020 08:58:50 +0800 Message-Id: <1594429136-20002-17-git-send-email-alex.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1594429136-20002-1-git-send-email-alex.shi@linux.alibaba.com> References: <1594429136-20002-1-git-send-email-alex.shi@linux.alibaba.com> X-Rspamd-Queue-Id: 299BD1800A67B X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: This patch reorder the isolation steps during munlock, move the lru lock to guard each pages, unfold __munlock_isolate_lru_page func, to do the preparation for lru lock change. __split_huge_page_refcount doesn't exist, but we still have to guard PageMlocked and PageLRU for tail page in __split_huge_page_tail. [lkp@intel.com: found a sleeping function bug ... at mm/rmap.c] Signed-off-by: Alex Shi Cc: Kirill A. Shutemov Cc: Andrew Morton Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Hugh Dickins Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- mm/mlock.c | 93 ++++++++++++++++++++++++++++++++++---------------------------- 1 file changed, 51 insertions(+), 42 deletions(-) diff --git a/mm/mlock.c b/mm/mlock.c index 228ba5a8e0a5..0bdde88b4438 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -103,25 +103,6 @@ void mlock_vma_page(struct page *page) } /* - * Isolate a page from LRU with optional get_page() pin. - * Assumes lru_lock already held and page already pinned. - */ -static bool __munlock_isolate_lru_page(struct page *page, bool getpage) -{ - if (TestClearPageLRU(page)) { - struct lruvec *lruvec; - - lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - if (getpage) - get_page(page); - del_page_from_lru_list(page, lruvec, page_lru(page)); - return true; - } - - return false; -} - -/* * Finish munlock after successful page isolation * * Page must be locked. This is a wrapper for try_to_munlock() @@ -181,6 +162,7 @@ static void __munlock_isolation_failed(struct page *page) unsigned int munlock_vma_page(struct page *page) { int nr_pages; + bool clearlru = false; pg_data_t *pgdat = page_pgdat(page); /* For try_to_munlock() and to serialize with page migration */ @@ -189,32 +171,42 @@ unsigned int munlock_vma_page(struct page *page) VM_BUG_ON_PAGE(PageTail(page), page); /* - * Serialize with any parallel __split_huge_page_refcount() which + * 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 hpage_nr_pages(). */ + get_page(page); + clearlru = TestClearPageLRU(page); spin_lock_irq(&pgdat->lru_lock); if (!TestClearPageMlocked(page)) { - /* Potentially, PTE-mapped THP: do not skip the rest PTEs */ - nr_pages = 1; - goto unlock_out; + if (clearlru) + SetPageLRU(page); + /* + * Potentially, PTE-mapped THP: do not skip the rest PTEs + * Reuse lock as memory barrier for release_pages racing. + */ + spin_unlock_irq(&pgdat->lru_lock); + put_page(page); + return 0; } nr_pages = hpage_nr_pages(page); __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages); - if (__munlock_isolate_lru_page(page, true)) { + if (clearlru) { + struct lruvec *lruvec; + + lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); + del_page_from_lru_list(page, lruvec, page_lru(page)); spin_unlock_irq(&pgdat->lru_lock); __munlock_isolated_page(page); - goto out; + } else { + spin_unlock_irq(&pgdat->lru_lock); + put_page(page); + __munlock_isolation_failed(page); } - __munlock_isolation_failed(page); - -unlock_out: - spin_unlock_irq(&pgdat->lru_lock); -out: return nr_pages - 1; } @@ -297,34 +289,51 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) pagevec_init(&pvec_putback); /* Phase 1: page isolation */ - spin_lock_irq(&zone->zone_pgdat->lru_lock); for (i = 0; i < nr; i++) { struct page *page = pvec->pages[i]; + struct lruvec *lruvec; + bool clearlru; - if (TestClearPageMlocked(page)) { - /* - * We already have pin from follow_page_mask() - * so we can spare the get_page() here. - */ - if (__munlock_isolate_lru_page(page, false)) - continue; - else - __munlock_isolation_failed(page); - } else { + clearlru = TestClearPageLRU(page); + spin_lock_irq(&zone->zone_pgdat->lru_lock); + + if (!TestClearPageMlocked(page)) { delta_munlocked++; + if (clearlru) + SetPageLRU(page); + goto putback; + } + + if (!clearlru) { + __munlock_isolation_failed(page); + goto putback; } /* + * Isolate this page. + * We already have pin from follow_page_mask() + * so we can spare the get_page() here. + */ + lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); + del_page_from_lru_list(page, lruvec, page_lru(page)); + spin_unlock_irq(&zone->zone_pgdat->lru_lock); + continue; + + /* * We won't be munlocking this page in the next phase * but we still need to release the follow_page_mask() * pin. We cannot do it under lru_lock however. If it's * the last pin, __page_cache_release() would deadlock. */ +putback: + spin_unlock_irq(&zone->zone_pgdat->lru_lock); pagevec_add(&pvec_putback, pvec->pages[i]); pvec->pages[i] = NULL; } + /* tempary disable irq, will remove later */ + local_irq_disable(); __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked); - spin_unlock_irq(&zone->zone_pgdat->lru_lock); + local_irq_enable(); /* Now we can release pins of pages that we are not munlocking */ pagevec_release(&pvec_putback);