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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 2F3ACC48BCF for ; Sat, 12 Jun 2021 09:46:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1009961249 for ; Sat, 12 Jun 2021 09:46:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231253AbhFLJsh (ORCPT ); Sat, 12 Jun 2021 05:48:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231193AbhFLJsh (ORCPT ); Sat, 12 Jun 2021 05:48:37 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A93EFC061574 for ; Sat, 12 Jun 2021 02:46:24 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id 11so4041128plk.12 for ; Sat, 12 Jun 2021 02:46:24 -0700 (PDT) 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=cStPclh9XG3RxOFyVxsu9zTH21TiQql+7187dLUWbK8=; b=eUO6qTRKBADJwUvuErZZeJR8S4O44jHtqy+r5h1kUNyB7U5lcux3/vJZGSz4EC02lO 7caZ1sMLwKh29iHmshLFiGfBTWgBDKKEjZjL3O5ByeTACbVC8GH2GUgoeg67eDlDasSR N0FiROzzDYmjEZB+5zshhVw9hSa+qmCcD233m++NOqgB+idXbQVGZwjP6bMNUaEkpb2W XRg1Nby+1RCfoKMTpIigJGUcKHGMaWhMd1hYUjUJaFdxBNuznmYHQ3/+Cqav/8LnsyOj DILszkKbXV/29+eg5CZ27W9r79KzqlhDBmcwEgL3FhTrZPAeNxW7QzuxWimHV8kAOXCe cRPA== 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=cStPclh9XG3RxOFyVxsu9zTH21TiQql+7187dLUWbK8=; b=AQ3nOY8cRIXgC25++Nu8UIbUgokuqu5FKJeIqbTeOojw6BEBbPgFP4eCM+SFx5v6q3 PmRpqRLlLCYvEbdFGg9276cnwhjP0s29e3Vhfps17SZecFG9qDlHf15tpbKjPz3GUROy 8DJCr6oclEz40Y71+yADfvh6mL8QC5L838bXVk6mGZxH+bmbLwoKMiR4vgmfm6tYMkqZ sLNM0GgArfrWRS0yhrhMzaGFbXXRqXlApEYSG2fio6vpdFswRefrS6V2qI9AtHiOz7Oo dAaGI53n0dBi7GTWOcWCUJnKUzK4WpzU+qVY6T2k3awlwkB9ko0CgQBC5QkaGvMGFNx2 nx0A== X-Gm-Message-State: AOAM530QF3Xfw1elz62YI28cXc3SXtwCpEKGYH81EYztpTXdxa+d12sN D0+9GUNInfic2AbW4w9cM5l8Fw== X-Google-Smtp-Source: ABdhPJxri4vZdp0HhrlywijdZcCZtQiBBCNKpg4WIBbifMFNu/V4m/2DPd2uuq3Hp+FCgOe5CZEYOw== X-Received: by 2002:a17:903:3112:b029:103:6340:3195 with SMTP id w18-20020a1709033112b029010363403195mr7899387plc.29.1623491184271; Sat, 12 Jun 2021 02:46:24 -0700 (PDT) Received: from localhost.tiktokd.org ([139.177.225.246]) by smtp.gmail.com with ESMTPSA id t39sm6929557pfg.147.2021.06.12.02.46.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sat, 12 Jun 2021 02:46:23 -0700 (PDT) From: Muchun Song To: mike.kravetz@oracle.com, akpm@linux-foundation.org, osalvador@suse.de, mhocko@suse.com, song.bao.hua@hisilicon.com, david@redhat.com, chenhuang5@huawei.com, bodeddub@amazon.com, corbet@lwn.net Cc: duanxiongchun@bytedance.com, fam.zheng@bytedance.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Muchun Song Subject: [PATCH v2 3/3] mm: hugetlb: introduce CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON Date: Sat, 12 Jun 2021 17:45:55 +0800 Message-Id: <20210612094555.71344-4-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20210612094555.71344-1-songmuchun@bytedance.com> References: <20210612094555.71344-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org When using HUGETLB_PAGE_FREE_VMEMMAP, the freeing unused vmemmap pages associated with each HugeTLB page is default off. Now the vmemmap is PMD mapped. So there is no side effect when this feature is enabled with no HugeTLB pages in the system. Someone may want to enable this feature in the compiler time instead of using boot command line. So add a config to make it default on when someone do not want to enable it via command line. Signed-off-by: Muchun Song --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ fs/Kconfig | 10 ++++++++++ mm/hugetlb_vmemmap.c | 6 ++++-- 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a01aadafee38..8eee439d943c 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1604,6 +1604,9 @@ on: enable the feature off: disable the feature + Built with CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON=y, + the default is on. + This is not compatible with memory_hotplug.memmap_on_memory. If both parameters are enabled, hugetlb_free_vmemmap takes precedence over memory_hotplug.memmap_on_memory. diff --git a/fs/Kconfig b/fs/Kconfig index f40b5b98f7ba..e78bc5daf7b0 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -245,6 +245,16 @@ config HUGETLB_PAGE_FREE_VMEMMAP depends on X86_64 depends on SPARSEMEM_VMEMMAP +config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON + bool "Default freeing vmemmap pages of HugeTLB to on" + default n + depends on HUGETLB_PAGE_FREE_VMEMMAP + help + When using HUGETLB_PAGE_FREE_VMEMMAP, the freeing unused vmemmap + pages associated with each HugeTLB page is default off. Say Y here + to enable freeing vmemmap pages of HugeTLB by default. It can then + be disabled on the command line via hugetlb_free_vmemmap=off. + config MEMFD_CREATE def_bool TMPFS || HUGETLBFS diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 06802056f296..c540c21e26f5 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -182,7 +182,7 @@ #define RESERVE_VMEMMAP_NR 2U #define RESERVE_VMEMMAP_SIZE (RESERVE_VMEMMAP_NR << PAGE_SHIFT) -bool hugetlb_free_vmemmap_enabled; +bool hugetlb_free_vmemmap_enabled = IS_ENABLED(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON); static int __init early_hugetlb_free_vmemmap_param(char *buf) { @@ -197,7 +197,9 @@ static int __init early_hugetlb_free_vmemmap_param(char *buf) if (!strcmp(buf, "on")) hugetlb_free_vmemmap_enabled = true; - else if (strcmp(buf, "off")) + else if (!strcmp(buf, "off")) + hugetlb_free_vmemmap_enabled = false; + else return -EINVAL; return 0; -- 2.11.0