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=-12.8 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 94412C4363A for ; Mon, 26 Oct 2020 14:55:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CC0222263 for ; Mon, 26 Oct 2020 14:55:19 +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="wxpBUBnO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1782667AbgJZOzS (ORCPT ); Mon, 26 Oct 2020 10:55:18 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:36965 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1782654AbgJZOzQ (ORCPT ); Mon, 26 Oct 2020 10:55:16 -0400 Received: by mail-pf1-f196.google.com with SMTP id 126so5903185pfu.4 for ; Mon, 26 Oct 2020 07:55:15 -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=3mpciXNwuWcA5SxSfqhs9A4AXvA+acZr3rKf1/b+yZ4=; b=wxpBUBnO46XYx1IyrgXw8jKQbFTfCS8wmkAHMTfSnaTjj3luNYlMLPhMZetrgkwfvx macN5wvljeYhYqBA560CER6ZjGtMQvNn1j9+UjUuaRdetFNulNxaYRbh1j66KudSwQWI eDRXiIwG2Hht2uvTqtKe1iUTUE5PVzZy/hVr9ipDqvXbcxEryyzfHe7RnNsDVEEJ95v+ lENGhvYH7S9+Jx72NaLpfo5QBPozjAIpU8u7V3pgpFLztrajR3ZMBMYE3IH+s5dtvJKN b8n3nFPnhOcCmq4Kf67F8IzSHOhCHkw3I5af0KzOV1gYUDtfBFis0u1qwULZH00Sn4f3 WNFA== 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=3mpciXNwuWcA5SxSfqhs9A4AXvA+acZr3rKf1/b+yZ4=; b=XzFpMvcJvWp6mixB4b3jgyTDGI8qQnmYcxa3tz6qGLEIxiDx+2Qkcibk55hzxhyCLi lRotqNzCsBPT2pNG7vaG0lk4d/0sIPtMoZJ+YB3kJVIOmNgUdLB90owSQRgYFFr4ylyu H9SKxk4UcJzW77+ViifmGtZpybSdnz0EpBBzOLQE9vWgc1HLsaeVmuDgWSTo853ygAtR hEBCqqwe+2oJ/wkML+X9kvDGWSaE592ZpaAso2bMA9EUdCaAg/+78XSSlMDjVGGKPLDB 8R+zff3HGnbzbf50B+/NawNFe1YM8FOz33AUBu9tjRSXLSXgUZe6o0zShmb2gBboCdl1 UScQ== X-Gm-Message-State: AOAM533Y4NgJoXO5rJmeo/OxZyVsbFSKCN1PS3V6NWviYamdjPc5r3Ys u8U8Zx7iA6l4Gklf4j5SevD3yA== X-Google-Smtp-Source: ABdhPJyrrJjqBxDZ4gmy4W3o6g0P8TouDAMt8VykFlzg75jHTBFST4T1YJx4SFz6D7HN8IASwdyp1A== X-Received: by 2002:a65:508a:: with SMTP id r10mr17564254pgp.307.1603724115200; Mon, 26 Oct 2020 07:55:15 -0700 (PDT) Received: from localhost.localdomain ([103.136.220.89]) by smtp.gmail.com with ESMTPSA id x123sm12042726pfb.212.2020.10.26.07.55.05 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Oct 2020 07:55:14 -0700 (PDT) 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 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 v2 13/19] mm/hugetlb: Add a BUILD_BUG_ON to check if struct page size is a power of two Date: Mon, 26 Oct 2020 22:51:08 +0800 Message-Id: <20201026145114.59424-14-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201026145114.59424-1-songmuchun@bytedance.com> References: <20201026145114.59424-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We only can free the unused vmemmap to the buddy system when the size of struct page is a power of two. So add a BUILD_BUG_ON to check the illegal case. Signed-off-by: Muchun Song --- mm/hugetlb.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index d98b55ad1a90..e3209fd2e6b2 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3776,6 +3776,10 @@ static int __init hugetlb_init(void) { int i; +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP + BUILD_BUG_ON_NOT_POWER_OF_2(sizeof(struct page)); +#endif + if (!hugepages_supported()) { if (hugetlb_max_hstate || default_hstate_max_huge_pages) pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n"); -- 2.20.1