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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 951FCC4742C for ; Fri, 13 Nov 2020 11:03:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40FAB2224C for ; Fri, 13 Nov 2020 11:03:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bytedance-com.20150623.gappssmtp.com header.i=@bytedance-com.20150623.gappssmtp.com header.b="0FY1bBXs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726495AbgKMLDE (ORCPT ); Fri, 13 Nov 2020 06:03:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726437AbgKMLCR (ORCPT ); Fri, 13 Nov 2020 06:02:17 -0500 Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0EC7FC061A4C for ; Fri, 13 Nov 2020 03:01:28 -0800 (PST) Received: by mail-pl1-x644.google.com with SMTP id s2so4379078plr.9 for ; Fri, 13 Nov 2020 03:01:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=tOaBoYHHig9NCQlC9kF5etq1J+Bfm3eBMm2Sx+lDC9A=; b=0FY1bBXsIYcDLc/vtlAVQoYH27ooDuEQbD+06g/beLVBOPdjhnMLVU9A/kqlh3T4zl ceOcdEHMd7WPwYNlvCwKyXK3/lGyDAta5zW2W9/T1YPP7AmWjGIqKoMJHqDzYFG5NYgx 48rJfq+iaKiXGwo0UEtYiIJDOrmYnVAAhZbgcFQnC1EiNO+H6MT1suV+4KLEp3Ukst3O F/u2klHTmOG0GE4nDr9v3APIKvxlg14w4EHblZBmghIuyLjktJwVIOEy9x1PTca2okZi 1iINOZ6Pxf/fKwPfuQTLBv7tVGOp83hbbljCAlC9d4qm42/gxUdPPQlFIQM6141JpSG/ e4Aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=tOaBoYHHig9NCQlC9kF5etq1J+Bfm3eBMm2Sx+lDC9A=; b=B05+meUcK1o0nu2BR+rT7Q7cpNEp4zOv0U5S5FJ0VqW4yU9nmKGvsI/9ENeToN5iTk cvr0MWPLZOa0xLP8u8DkAvBCNWa28EOJKu9SpCG62yekncAewkXoU3tihZP9+8z1fGM2 DxcrinEO01LQn0pTLI40RBeYyDDNBs8kaf/e7ymis/PJ67l1o74pQAqxd2WcOYPPlgPk VwNYl066MrI2+nwYkM61u44yb8iWk2Aw2dzt49J44Am7QQ/N9eMM2tHflkZGGdaSOVKv BuMvKzLoY1QZVfrQvWPRJ11O/VKpkMDesSEa3aWyOXAL2umWAn6cVM0o6cXyHjEKUzg0 Kx+w== X-Gm-Message-State: AOAM531/2HfyeBv15o6okUmHognBcgktqXnzz1anqPt6G1v6JAUVeWwg hQqNJsg5WMFlPuu7xjHcxkGaBg== X-Google-Smtp-Source: ABdhPJwxjMYztWRHjZezcYZqZHmla6x+5SMEjoB0WH1+Uuko6Mf4T0NnhsjY85Bi51WHYWPsZ8jUNA== X-Received: by 2002:a17:902:7b90:b029:d6:ad06:d4c0 with SMTP id w16-20020a1709027b90b02900d6ad06d4c0mr1545505pll.35.1605265287351; Fri, 13 Nov 2020 03:01:27 -0800 (PST) Received: from localhost.localdomain ([61.120.150.78]) by smtp.gmail.com with ESMTPSA id f1sm8909959pfc.56.2020.11.13.03.01.13 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Nov 2020 03:01:26 -0800 (PST) From: Muchun Song To: corbet@lwn.net, mike.kravetz@oracle.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, paulmck@kernel.org, mchehab+huawei@kernel.org, pawan.kumar.gupta@linux.intel.com, rdunlap@infradead.org, oneukum@suse.com, anshuman.khandual@arm.com, jroedel@suse.de, almasrymina@google.com, rientjes@google.com, willy@infradead.org, osalvador@suse.de, mhocko@suse.com Cc: duanxiongchun@bytedance.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Muchun Song Subject: [PATCH v4 03/21] mm/hugetlb: Introduce a new config HUGETLB_PAGE_FREE_VMEMMAP Date: Fri, 13 Nov 2020 18:59:34 +0800 Message-Id: <20201113105952.11638-4-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201113105952.11638-1-songmuchun@bytedance.com> References: <20201113105952.11638-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org The purpose of introducing HUGETLB_PAGE_FREE_VMEMMAP is to configure whether to enable the feature of freeing unused vmemmap associated with HugeTLB pages. Now only support x86. Signed-off-by: Muchun Song --- arch/x86/mm/init_64.c | 2 +- fs/Kconfig | 14 ++++++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 0a45f062826e..0435bee2e172 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1225,7 +1225,7 @@ static struct kcore_list kcore_vsyscall; static void __init register_page_bootmem_info(void) { -#ifdef CONFIG_NUMA +#if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP) int i; for_each_online_node(i) diff --git a/fs/Kconfig b/fs/Kconfig index 976e8b9033c4..67e1bc99574f 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -245,6 +245,20 @@ config HUGETLBFS config HUGETLB_PAGE def_bool HUGETLBFS +config HUGETLB_PAGE_FREE_VMEMMAP + def_bool HUGETLB_PAGE + depends on X86 + depends on SPARSEMEM_VMEMMAP + depends on HAVE_BOOTMEM_INFO_NODE + help + When using SPARSEMEM_VMEMMAP, the system can save up some memory + from pre-allocated HugeTLB pages when they are not used. 6 pages + per 2MB HugeTLB page and 4094 per 1GB HugeTLB page. + + When the pages are going to be used or freed up, the vmemmap array + representing that range needs to be remapped again and the pages + we discarded earlier need to be rellocated again. + config MEMFD_CREATE def_bool TMPFS || HUGETLBFS -- 2.11.0