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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6533CCCA47B for ; Mon, 13 Jun 2022 06:35:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236002AbiFMGfn (ORCPT ); Mon, 13 Jun 2022 02:35:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235656AbiFMGfk (ORCPT ); Mon, 13 Jun 2022 02:35:40 -0400 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98F06BCAB for ; Sun, 12 Jun 2022 23:35:39 -0700 (PDT) Received: by mail-pg1-x52d.google.com with SMTP id s135so4707370pgs.10 for ; Sun, 12 Jun 2022 23:35:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2+OKPYQ5REAoye/wSsuy111hflzgcPbPLQAUS9w4vzY=; b=UYN43vXERJXZ9csVHQZAu3w+v7BI/PQ0oeR4+TZu85yj6WdN/18M7tPeNA86JQv0e9 SgArwTPIRb2QOuLEAdNysGtz7p4ElisPmsr3carhhenLFpoFRcylbY/nbwXXKm2HtLRF Wol3JvHDVcHMeKhemIgfBhErkg6/Jo7+PB+1RDjJb7PRfjKx2EldoY8ueWHgFrIyaC5f 4irSNHL3qy7UKj3th4VmZDa8vJ4HYoc01II29r3nFIT7jgbCEGQXpmHxkYZbk+1TRwJR cY4zcduFoLB93qL6h4m9LTBxkNG2//NyIft3/u5IYhYM0QwOCiIswLcEdxAe2XGt3SIx f1PQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2+OKPYQ5REAoye/wSsuy111hflzgcPbPLQAUS9w4vzY=; b=ioElSlymWUtap3jhI+0aUMERU96VMKmKgkbsY4V/fhCZXvjxQw40BbOG7u1ch0UgMF U2xGzUTKV334LhXbsnAKThXVMjg5e6LTHGQdaKRobgU0AWBY94xZThp7Y8nZ3o1XGnIF L3mZ4BiCLHiW6pNfNEVzhEtWeXLgs3iuBzY/Ln6/B6A6Lp1JsBCCE/nmRNPcvo4/J67o qsq6BanZhjEZb7uhsHw+HV1UZkZ3UnLksQX3siPa55zweYfwU/je/HvdhRS7jO0qjOep qi8E91/xbhevimFLgjPBbzyg+ARqk+vvlbk3/SBwGmwdneqESwHmItgPQ4cLEyY5GBqn FuJQ== X-Gm-Message-State: AOAM531oXbrlhrVDjze30+hl22BdQMr4bjTYwto7x9EoKq0qcKfblpJb VYSi2uvzX6DDV8Z16Yb1y7SVUX6Vr1hwwSOr98s= X-Google-Smtp-Source: ABdhPJxz7UwWsexBbVriPZbR0Xz+JC+GNqKyElGl7birTSFGxX0z0EQ/fFZlYKwK8LYDlaLorQU6Ug== X-Received: by 2002:a63:cc09:0:b0:3fb:aae7:4964 with SMTP id x9-20020a63cc09000000b003fbaae74964mr49566503pgf.118.1655102139008; Sun, 12 Jun 2022 23:35:39 -0700 (PDT) Received: from FVFYT0MHHV2J.bytedance.net ([139.177.225.255]) by smtp.gmail.com with ESMTPSA id v3-20020aa799c3000000b0051bc538baadsm4366554pfi.184.2022.06.12.23.35.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 12 Jun 2022 23:35:38 -0700 (PDT) From: Muchun Song To: mike.kravetz@oracle.com, david@redhat.com, akpm@linux-foundation.org, corbet@lwn.net Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Muchun Song Subject: [PATCH 3/6] mm: hugetlb_vmemmap: introduce the name HVO Date: Mon, 13 Jun 2022 14:35:09 +0800 Message-Id: <20220613063512.17540-4-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.1 (Apple Git-133) In-Reply-To: <20220613063512.17540-1-songmuchun@bytedance.com> References: <20220613063512.17540-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org It it inconvenient to mention the feature of optimizing vmemmap pages associated with HugeTLB pages when communicating with others since there is no specific or abbreviated name for it when it is first introduced. Let us give it a name HVO (HugeTLB Vmemmap Optimization) from now. This commit also updates the document about "hugetlb_free_vmemmap" by the way discussed in thread [1]. Link: https://lore.kernel.org/all/21aae898-d54d-cc4b-a11f-1bb7fddcfffa@redhat.com/ [1] Signed-off-by: Muchun Song --- Documentation/admin-guide/kernel-parameters.txt | 7 ++++--- Documentation/admin-guide/mm/hugetlbpage.rst | 3 +-- Documentation/admin-guide/sysctl/vm.rst | 3 +-- fs/Kconfig | 13 ++++++------- mm/hugetlb_vmemmap.c | 8 ++++---- mm/hugetlb_vmemmap.h | 4 ++-- 6 files changed, 18 insertions(+), 20 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 391b43fee93e..7539553b3fb0 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1725,12 +1725,13 @@ hugetlb_free_vmemmap= [KNL] Reguires CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP enabled. + Control if HugeTLB Vmemmap Optimization (HVO) is enabled. Allows heavy hugetlb users to free up some more memory (7 * PAGE_SIZE for each 2MB hugetlb page). - Format: { [oO][Nn]/Y/y/1 | [oO][Ff]/N/n/0 (default) } + Format: { on | off (default) } - [oO][Nn]/Y/y/1: enable the feature - [oO][Ff]/N/n/0: disable the feature + on: enable HVO + off: disable HVO Built with CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON=y, the default is on. diff --git a/Documentation/admin-guide/mm/hugetlbpage.rst b/Documentation/admin-guide/mm/hugetlbpage.rst index a90330d0a837..64e0d5c512e7 100644 --- a/Documentation/admin-guide/mm/hugetlbpage.rst +++ b/Documentation/admin-guide/mm/hugetlbpage.rst @@ -164,8 +164,7 @@ default_hugepagesz will all result in 256 2M huge pages being allocated. Valid default huge page size is architecture dependent. hugetlb_free_vmemmap - When CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is set, this enables optimizing - unused vmemmap pages associated with each HugeTLB page. + When CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is set, this enables HVO. When multiple huge page sizes are supported, ``/proc/sys/vm/nr_hugepages`` indicates the current number of pre-allocated huge pages of the default size. diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index d7374a1e8ac9..c9f35db973f0 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -569,8 +569,7 @@ This knob is not available when the size of 'struct page' (a structure defined in include/linux/mm_types.h) is not power of two (an unusual system config could result in this). -Enable (set to 1) or disable (set to 0) the feature of optimizing vmemmap pages -associated with each HugeTLB page. +Enable (set to 1) or disable (set to 0) HugeTLB Vmemmap Optimization (HVO). Once enabled, the vmemmap pages of subsequent allocation of HugeTLB pages from buddy allocator will be optimized (7 pages per 2MB HugeTLB page and 4095 pages diff --git a/fs/Kconfig b/fs/Kconfig index 5976eb33535f..2f9fd840cb66 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -247,8 +247,7 @@ config HUGETLB_PAGE # # Select this config option from the architecture Kconfig, if it is preferred -# to enable the feature of minimizing overhead of struct page associated with -# each HugeTLB page. +# to enable the feature of HugeTLB Vmemmap Optimization (HVO). # config ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP bool @@ -259,14 +258,14 @@ config HUGETLB_PAGE_OPTIMIZE_VMEMMAP depends on SPARSEMEM_VMEMMAP config HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON - bool "Default optimizing vmemmap pages of HugeTLB to on" + bool "Default HugeTLB Vmemmap Optimization (HVO) to on" default n depends on HUGETLB_PAGE_OPTIMIZE_VMEMMAP help - When using HUGETLB_PAGE_OPTIMIZE_VMEMMAP, the optimizing unused vmemmap - pages associated with each HugeTLB page is default off. Say Y here - to enable optimizing vmemmap pages of HugeTLB by default. It can then - be disabled on the command line via hugetlb_free_vmemmap=off. + When using HUGETLB_PAGE_OPTIMIZE_VMEMMAP, the HugeTLB Vmemmap + Optimization (HVO) is off by default. Say Y here to enable HVO + by default. It can then be disabled on the command line via + hugetlb_free_vmemmap=off or sysctl. config MEMFD_CREATE def_bool TMPFS || HUGETLBFS diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 132dc83f0130..c10540993577 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -1,8 +1,8 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Optimize vmemmap pages associated with HugeTLB + * HugeTLB Vmemmap Optimization (HVO) * - * Copyright (c) 2020, Bytedance. All rights reserved. + * Copyright (c) 2020, ByteDance. All rights reserved. * * Author: Muchun Song * @@ -120,8 +120,8 @@ void __init hugetlb_vmemmap_init(struct hstate *h) /* * There are only (RESERVE_VMEMMAP_SIZE / sizeof(struct page)) struct - * page structs that can be used when CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP, - * so add a BUILD_BUG_ON to catch invalid usage of the tail struct page. + * page structs that can be used when HVO is enabled, add a BUILD_BUG_ON + * to catch invalid usage of the tail page structs. */ BUILD_BUG_ON(__NR_USED_SUBPAGE >= RESERVE_VMEMMAP_SIZE / sizeof(struct page)); diff --git a/mm/hugetlb_vmemmap.h b/mm/hugetlb_vmemmap.h index 109b0a53b6fe..ba66fadad9fc 100644 --- a/mm/hugetlb_vmemmap.h +++ b/mm/hugetlb_vmemmap.h @@ -1,8 +1,8 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Optimize vmemmap pages associated with HugeTLB + * HugeTLB Vmemmap Optimization (HVO) * - * Copyright (c) 2020, Bytedance. All rights reserved. + * Copyright (c) 2020, ByteDance. All rights reserved. * * Author: Muchun Song */ -- 2.11.0