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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 CED00C43387 for ; Fri, 28 Dec 2018 12:14:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F4502148E for ; Fri, 28 Dec 2018 12:14:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545999282; bh=3cwsIjh3ApljIwoxs1Z8F/paLZJXh2OhOoTcBzp7XiM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MIFvh6cNGLBnN71+QS5VMkwk4eCCA6zHIuMpOWwpT6AtJJei7Nj0CL9CQLdGbQPfT dFdhNlMAmt8Zo2RZSSLlMuSmNAEYIwGsxFwj6qGL/0u3PYHwQsDWXbGd7lTqGOee/I lMEuztU6+sZ9SppS+2bbDEAD9xrsNUzpp0GPiAYg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731166AbeL1MOm (ORCPT ); Fri, 28 Dec 2018 07:14:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:33468 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731098AbeL1MOe (ORCPT ); Fri, 28 Dec 2018 07:14:34 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 83E1C20866; Fri, 28 Dec 2018 12:14:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545999274; bh=3cwsIjh3ApljIwoxs1Z8F/paLZJXh2OhOoTcBzp7XiM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YnOyPwb4Cj5m/0OZtaDhuGi5H5RU5Zg8yMhDgGC9Si2I8g8aRfAX4t9hBD6PuK35Q E1fLDv8G6uSlPMZ/jymYUI9v6t9QQJtcokXphxffnsebWAqTbhsPJIGw5y2Q+saq2X NvwQJRsJdQx193M+9XCcvCOhVak8ui2QrIoFZmpk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Kirill A. Shutemov" , Martin Schwidefsky , Sasha Levin Subject: [PATCH 4.19 31/46] mm: add mm_pxd_folded checks to pgtable_bytes accounting functions Date: Fri, 28 Dec 2018 12:52:25 +0100 Message-Id: <20181228113126.637583556@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20181228113124.971620049@linuxfoundation.org> References: <20181228113124.971620049@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 6d212db11947ae5464e4717536ed9faf61c01e86 ] The common mm code calls mm_dec_nr_pmds() and mm_dec_nr_puds() in free_pgtables() if the address range spans a full pud or pmd. If mm_dec_nr_puds/mm_dec_nr_pmds are non-empty due to configuration settings they blindly subtract the size of the pmd or pud table from pgtable_bytes even if the pud or pmd page table layer is folded. Add explicit mm_[pmd|pud]_folded checks to the four pgtable_bytes accounting functions mm_inc_nr_puds, mm_inc_nr_pmds, mm_dec_nr_puds and mm_dec_nr_pmds. As the check for folded page tables can be overwritten by the architecture, this allows to keep a correct pgtable_bytes value for platforms that use a dynamic number of page table levels. Acked-by: Kirill A. Shutemov Signed-off-by: Martin Schwidefsky Signed-off-by: Sasha Levin --- include/linux/mm.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 0416a7204be3..e899460f1bc5 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1724,11 +1724,15 @@ int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address); static inline void mm_inc_nr_puds(struct mm_struct *mm) { + if (mm_pud_folded(mm)) + return; atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes); } static inline void mm_dec_nr_puds(struct mm_struct *mm) { + if (mm_pud_folded(mm)) + return; atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes); } #endif @@ -1748,11 +1752,15 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); static inline void mm_inc_nr_pmds(struct mm_struct *mm) { + if (mm_pmd_folded(mm)) + return; atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes); } static inline void mm_dec_nr_pmds(struct mm_struct *mm) { + if (mm_pmd_folded(mm)) + return; atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes); } #endif -- 2.19.1