From patchwork Tue Dec 22 14:24:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 11986787 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=-16.7 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 C0285C43381 for ; Tue, 22 Dec 2020 14:32:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D62B2312E for ; Tue, 22 Dec 2020 14:32:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727886AbgLVOcE (ORCPT ); Tue, 22 Dec 2020 09:32:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39988 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727877AbgLVOcD (ORCPT ); Tue, 22 Dec 2020 09:32:03 -0500 Received: from mail-pl1-x629.google.com (mail-pl1-x629.google.com [IPv6:2607:f8b0:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36B97C061248 for ; Tue, 22 Dec 2020 06:31:23 -0800 (PST) Received: by mail-pl1-x629.google.com with SMTP id x12so7505466plr.10 for ; Tue, 22 Dec 2020 06:31:23 -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=1seh5M2ZUWi9UZdev/oNQbO4cU6q+XgrZrg9wVC/rxI=; b=BmDQtNH2NR0AF6lP6dxq23r14xZG2DlZb8P9suzwQaNZvdsoqxz2s0GXzA3nZHToV5 qu84jRwDui1Tml+0SIenBvWz2p62UliZemDh5icDRIW+H/r4nIbccIkSW+FRMrOqLNuJ FVfNAmocE4t1okkwuky0BmTiUG2NnbHzoECZz2iIiiktrUFdJ0Zfr8UD+dl6zvEBxPgq M492QnFsjVHED72zxZZkjgzG2MNLJVkV9u1qeOd932h+JrNwtS6vVRiuwyJel5eKv/9E fUJHpTCDLjF3ZjXfbpCM11KpkxFeaL0G7oGCrtDY1SdR58YOyKfeeJ+e4xD0TZCuFp2C dYUA== 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=1seh5M2ZUWi9UZdev/oNQbO4cU6q+XgrZrg9wVC/rxI=; b=bz3y4bXXHFN4cgx+uPadr5nJXeytve0AW9dlahQjm9WBC/qHR9nVi7cV64FK5xD8Si laWUp7hp6XH93EEMSFMYqvW320NM+A5eIln7xtxar0vBrxUuK5Q1HuW90uCtxNB4GE88 DAsjsoHeaDQWoDmy+YHTgFLcXjXkBaL2NNXw2O/HGFIwGqpYtNqqqtcuvaVd6jpH8GIM dYebPMc9bMsQ7J3W7sF13nhDprmjomDmmf9Uih4jrOpVBdkOR+osnxco+GVBrruwT3MM oPkAlNW/FiQyeX4Ki/M47mA5iwoWrZR9gjR0VkocLpBCET3D/loMQxd/3BpLpAO3g8SV 5L2w== X-Gm-Message-State: AOAM533WBStZNwSRkbWMtlFxUt374dsqBzBCPDcb6kvg5K7Ez8AAFtg6 I2L7oWWClG+vC/BnefSHPYd2NQ== X-Google-Smtp-Source: ABdhPJzhMmKvQnNlH+bczONQXN1FohKsO2+35KUwG81SzatSK6MxjwvChkwr8r/0rr9MCW637ooCVg== X-Received: by 2002:a17:90a:6d62:: with SMTP id z89mr22819034pjj.71.1608647482726; Tue, 22 Dec 2020 06:31:22 -0800 (PST) Received: from localhost.bytedance.net ([139.177.225.247]) by smtp.gmail.com with ESMTPSA id a31sm21182088pgb.93.2020.12.22.06.31.12 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 22 Dec 2020 06:31:22 -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, song.bao.hua@hisilicon.com, david@redhat.com, naoya.horiguchi@nec.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 v11 10/11] mm/hugetlb: Gather discrete indexes of tail page Date: Tue, 22 Dec 2020 22:24:39 +0800 Message-Id: <20201222142440.28930-11-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201222142440.28930-1-songmuchun@bytedance.com> References: <20201222142440.28930-1-songmuchun@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org For HugeTLB page, there are more metadata to save in the struct page. But the head struct page cannot meet our needs, so we have to abuse other tail struct page to store the metadata. In order to avoid conflicts caused by subsequent use of more tail struct pages, we can gather these discrete indexes of tail struct page. In this case, it will be easier to add a new tail page index later. There are only (RESERVE_VMEMMAP_SIZE / sizeof(struct page)) struct page structs that can be used when CONFIG_HUGETLB_PAGE_FREE_VMEMMAP, so add a BUILD_BUG_ON to catch invalid usage of the tail struct page. Signed-off-by: Muchun Song Reviewed-by: Oscar Salvador --- include/linux/hugetlb.h | 13 +++++++++++++ include/linux/hugetlb_cgroup.h | 15 +++++++++------ mm/hugetlb.c | 35 +++++++++++++++++++++++++++-------- mm/hugetlb_vmemmap.c | 8 ++++++++ 4 files changed, 57 insertions(+), 14 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 66d82ae7b712..7295f6b3d55e 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -28,6 +28,19 @@ typedef struct { unsigned long pd; } hugepd_t; #include #include +enum { + SUBPAGE_INDEX_ACTIVE = 1, /* reuse page flags of PG_private */ + SUBPAGE_INDEX_TEMPORARY, /* reuse page->mapping */ +#ifdef CONFIG_CGROUP_HUGETLB + SUBPAGE_INDEX_CGROUP = SUBPAGE_INDEX_TEMPORARY,/* reuse page->private */ + SUBPAGE_INDEX_CGROUP_RSVD, /* reuse page->private */ +#endif +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP + SUBPAGE_INDEX_HWPOISON, /* reuse page->private */ +#endif + NR_USED_SUBPAGE, +}; + struct hugepage_subpool { spinlock_t lock; long count; diff --git a/include/linux/hugetlb_cgroup.h b/include/linux/hugetlb_cgroup.h index 2ad6e92f124a..3d3c1c49efe4 100644 --- a/include/linux/hugetlb_cgroup.h +++ b/include/linux/hugetlb_cgroup.h @@ -24,8 +24,9 @@ struct file_region; /* * Minimum page order trackable by hugetlb cgroup. * At least 4 pages are necessary for all the tracking information. - * The second tail page (hpage[2]) is the fault usage cgroup. - * The third tail page (hpage[3]) is the reservation usage cgroup. + * The second tail page (hpage[SUBPAGE_INDEX_CGROUP]) is the fault + * usage cgroup. The third tail page (hpage[SUBPAGE_INDEX_CGROUP_RSVD]) + * is the reservation usage cgroup. */ #define HUGETLB_CGROUP_MIN_ORDER 2 @@ -66,9 +67,9 @@ __hugetlb_cgroup_from_page(struct page *page, bool rsvd) if (compound_order(page) < HUGETLB_CGROUP_MIN_ORDER) return NULL; if (rsvd) - return (struct hugetlb_cgroup *)page[3].private; + return (void *)page_private(page + SUBPAGE_INDEX_CGROUP_RSVD); else - return (struct hugetlb_cgroup *)page[2].private; + return (void *)page_private(page + SUBPAGE_INDEX_CGROUP); } static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page) @@ -90,9 +91,11 @@ static inline int __set_hugetlb_cgroup(struct page *page, if (compound_order(page) < HUGETLB_CGROUP_MIN_ORDER) return -1; if (rsvd) - page[3].private = (unsigned long)h_cg; + set_page_private(page + SUBPAGE_INDEX_CGROUP_RSVD, + (unsigned long)h_cg); else - page[2].private = (unsigned long)h_cg; + set_page_private(page + SUBPAGE_INDEX_CGROUP, + (unsigned long)h_cg); return 0; } diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f19e841236d7..2764af5fa0b3 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1356,6 +1356,7 @@ static inline void __update_and_free_page(struct hstate *h, struct page *page) schedule_work(&hpage_update_work); } +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP static inline void hwpoison_subpage_deliver(struct hstate *h, struct page *head) { struct page *page; @@ -1363,7 +1364,7 @@ static inline void hwpoison_subpage_deliver(struct hstate *h, struct page *head) if (!PageHWPoison(head) || !free_vmemmap_pages_per_hpage(h)) return; - page = head + page_private(head + 4); + page = head + page_private(head + SUBPAGE_INDEX_HWPOISON); /* * Move PageHWPoison flag from head page to the raw error page, @@ -1382,7 +1383,7 @@ static inline void hwpoison_subpage_set(struct hstate *h, struct page *head, return; if (free_vmemmap_pages_per_hpage(h)) { - set_page_private(head + 4, page - head); + set_page_private(head + SUBPAGE_INDEX_HWPOISON, page - head); } else if (page != head) { /* * Move PageHWPoison flag from head page to the raw error page, @@ -1392,6 +1393,24 @@ static inline void hwpoison_subpage_set(struct hstate *h, struct page *head, ClearPageHWPoison(head); } } +#else +static inline void hwpoison_subpage_deliver(struct hstate *h, struct page *head) +{ +} + +static inline void hwpoison_subpage_set(struct hstate *h, struct page *head, + struct page *page) +{ + if (PageHWPoison(head) && page != head) { + /* + * Move PageHWPoison flag from head page to the raw error page, + * which makes any subpages rather than the error page reusable. + */ + SetPageHWPoison(page); + ClearPageHWPoison(head); + } +} +#endif static void update_and_free_page(struct hstate *h, struct page *page) { @@ -1459,20 +1478,20 @@ struct hstate *size_to_hstate(unsigned long size) bool page_huge_active(struct page *page) { VM_BUG_ON_PAGE(!PageHuge(page), page); - return PageHead(page) && PagePrivate(&page[1]); + return PageHead(page) && PagePrivate(&page[SUBPAGE_INDEX_ACTIVE]); } /* never called for tail page */ static void set_page_huge_active(struct page *page) { VM_BUG_ON_PAGE(!PageHeadHuge(page), page); - SetPagePrivate(&page[1]); + SetPagePrivate(&page[SUBPAGE_INDEX_ACTIVE]); } static void clear_page_huge_active(struct page *page) { VM_BUG_ON_PAGE(!PageHeadHuge(page), page); - ClearPagePrivate(&page[1]); + ClearPagePrivate(&page[SUBPAGE_INDEX_ACTIVE]); } /* @@ -1484,17 +1503,17 @@ static inline bool PageHugeTemporary(struct page *page) if (!PageHuge(page)) return false; - return (unsigned long)page[2].mapping == -1U; + return (unsigned long)page[SUBPAGE_INDEX_TEMPORARY].mapping == -1U; } static inline void SetPageHugeTemporary(struct page *page) { - page[2].mapping = (void *)-1U; + page[SUBPAGE_INDEX_TEMPORARY].mapping = (void *)-1U; } static inline void ClearPageHugeTemporary(struct page *page) { - page[2].mapping = NULL; + page[SUBPAGE_INDEX_TEMPORARY].mapping = NULL; } static void __free_huge_page(struct page *page) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 7dcb4aa1e512..6b8f7bb2273e 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -242,6 +242,14 @@ void __init hugetlb_vmemmap_init(struct hstate *h) unsigned int nr_pages = pages_per_huge_page(h); unsigned int vmemmap_pages; + /* + * There are only (RESERVE_VMEMMAP_SIZE / sizeof(struct page)) struct + * page structs that can be used when CONFIG_HUGETLB_PAGE_FREE_VMEMMAP, + * so add a BUILD_BUG_ON to catch invalid usage of the tail struct page. + */ + BUILD_BUG_ON(NR_USED_SUBPAGE >= + RESERVE_VMEMMAP_SIZE / sizeof(struct page)); + if (!hugetlb_free_vmemmap_enabled) return;