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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 6A25DC43457 for ; Fri, 16 Oct 2020 02:42:17 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id EA33820878 for ; Fri, 16 Oct 2020 02:42:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="m/roYdpT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EA33820878 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 82B3B94001F; Thu, 15 Oct 2020 22:42:16 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7B269940007; Thu, 15 Oct 2020 22:42:16 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 67AD494001F; Thu, 15 Oct 2020 22:42:16 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0250.hostedemail.com [216.40.44.250]) by kanga.kvack.org (Postfix) with ESMTP id 3AB35940007 for ; Thu, 15 Oct 2020 22:42:16 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id BDBF1180AD811 for ; Fri, 16 Oct 2020 02:42:15 +0000 (UTC) X-FDA: 77376239430.25.size23_270290927219 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id 93EC11804E3A0 for ; Fri, 16 Oct 2020 02:42:15 +0000 (UTC) X-HE-Tag: size23_270290927219 X-Filterd-Recvd-Size: 2932 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf11.hostedemail.com (Postfix) with ESMTP for ; Fri, 16 Oct 2020 02:42:15 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E09312087D; Fri, 16 Oct 2020 02:42:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816134; bh=zHASiUDz758IL+Etgbjq3oRtoew3nAEe4RdntxV5XTM=; h=Date:From:To:Subject:In-Reply-To:From; b=m/roYdpTtJszbqwKr8/8JWGW9j6tCwY9zNfLrJuRFf4Sso920sWI7TZfv9oN+ErH5 Syjihra/fP+0z5+zjYPF4tu0B/e1+EB7vUdZPqSUJ96i8xSz8Uru8JElMEooTCh0g/ RDlSTvImfcwYXZhFl+5J3k5c6FqzqzcPA58mvSXE= Date: Thu, 15 Oct 2020 19:42:13 -0700 From: Andrew Morton To: akpm@linux-foundation.org, kirill@shutemov.name, linux-mm@kvack.org, mm-commits@vger.kernel.org, sjpark@amazon.de, torvalds@linux-foundation.org, willy@infradead.org, ying.huang@intel.com Subject: [patch 022/156] mm/huge_memory: fix total_mapcount assumption of page size Message-ID: <20201016024213.uqBvLymdF%akpm@linux-foundation.org> In-Reply-To: <20201015192732.f448da14e9854c7cb7299956@linux-foundation.org> User-Agent: s-nail v14.8.16 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: From: "Kirill A. Shutemov" Subject: mm/huge_memory: fix total_mapcount assumption of page size File THPs may now be of arbitrary order. Link: https://lkml.kernel.org/r/20200908195539.25896-5-willy@infradead.org Signed-off-by: Kirill A. Shutemov Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: SeongJae Park Cc: Huang Ying Signed-off-by: Andrew Morton --- mm/huge_memory.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-fix-total_mapcount-assumption-of-page-size +++ a/mm/huge_memory.c @@ -2494,7 +2494,7 @@ static void __split_huge_page(struct pag int total_mapcount(struct page *page) { - int i, compound, ret; + int i, compound, nr, ret; VM_BUG_ON_PAGE(PageTail(page), page); @@ -2502,16 +2502,17 @@ int total_mapcount(struct page *page) return atomic_read(&page->_mapcount) + 1; compound = compound_mapcount(page); + nr = compound_nr(page); if (PageHuge(page)) return compound; ret = compound; - for (i = 0; i < HPAGE_PMD_NR; i++) + for (i = 0; i < nr; i++) ret += atomic_read(&page[i]._mapcount) + 1; /* File pages has compound_mapcount included in _mapcount */ if (!PageAnon(page)) - return ret - compound * HPAGE_PMD_NR; + return ret - compound * nr; if (PageDoubleMap(page)) - ret -= HPAGE_PMD_NR; + ret -= nr; return ret; } _