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 E1A29C433B4 for ; Thu, 15 Apr 2021 08:42:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BCD9F613B1 for ; Thu, 15 Apr 2021 08:42:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231902AbhDOInT (ORCPT ); Thu, 15 Apr 2021 04:43:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231917AbhDOInP (ORCPT ); Thu, 15 Apr 2021 04:43:15 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 748D6C061756 for ; Thu, 15 Apr 2021 01:42:53 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id em21-20020a17090b0155b029014e204a81e6so4377402pjb.1 for ; Thu, 15 Apr 2021 01:42:53 -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=6TWaOIOsTerxj3mJL6eq87dt1yIFOG9nTLeeYfIsCVs=; b=2B/7nhsw2xEIQKmLjJ7aBwin8TXHNpJiJkmdaLsd979e20DhPX4OMUfCVwZIFa2TN4 F/JXI4BhmvN30z+IJcoaGsSIdaxHjCXldThwCavxssw+Fi7NzGjeMvlk/GkUcY2iOVtR k8m0TzBYtqg7+F4PQHlAbcU8TNnsdAaTCP2nnPxwkubSdyNZ8SY48XonOImvd/s8q3zW fQHqdD2UM5LDQIYHbLQRHjdlIXNl5dEWthO2vW8KOaJjiQ98IDxD8CAd/NJJFVzNf9j2 tERae+6Y3FjRozk4SF6gNSXWcd7uKEAgAqKD9k0BS4ZREM3HwIA3E4m/FnsN8bhe9IKD AO9w== 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=6TWaOIOsTerxj3mJL6eq87dt1yIFOG9nTLeeYfIsCVs=; b=oLr0znwh5fR+dJNgMHyhma0Iss6NjDQWrI84frLEvxvcjs9SnZ/1MQQHpvwXtRFeRA kdzeLdahqzrioLyY4F/G65rmDaCu/XUlrmrj4ImpZZkUjZ2fFaF5bPvzzacu8xZdxUAD LfI53VcC56txPeV1R6aQBdsh8XWFQPxr33tBN6zysNJnT97AQi741Y2bNn+wwQVYJOa0 MxwDcSS3p4idL1TdRJI3V1IMe1LhZeY3OiBTyFzisdwo1e6W3QiUlUiUDj5bvK8msTWE 4Vqm/8t+lA//N5rl6okmk7O4deu+XFdWMqd39cEd2Wi0imYvHZRkpTM0geD61HlUv3K9 81xg== X-Gm-Message-State: AOAM532IjZ/gqMM1PZoGX8afttHzCZTwNnMHxEDeLz3O0CxJYJGti8DK LZUFJ6rmPUuL/oi4Lq3VeQNEVQ== X-Google-Smtp-Source: ABdhPJwTNMUz7wpKbNzAkS7+rcZjQm5CQ+OdHPmFYkuycOXyiO5NtJld2ZwUwxrLL8A8DqogSGwLjA== X-Received: by 2002:a17:902:8601:b029:e6:7b87:8add with SMTP id f1-20020a1709028601b02900e67b878addmr2736039plo.3.1618476172961; Thu, 15 Apr 2021 01:42:52 -0700 (PDT) Received: from localhost.localdomain ([139.177.225.234]) by smtp.gmail.com with ESMTPSA id e13sm1392365pgt.91.2021.04.15.01.42.41 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 15 Apr 2021 01:42:52 -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, 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, joao.m.martins@oracle.com Cc: duanxiongchun@bytedance.com, fam.zheng@bytedance.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Muchun Song , Miaohe Lin , Chen Huang , Bodeddula Balasubramaniam Subject: [PATCH v20 3/9] mm: hugetlb: gather discrete indexes of tail page Date: Thu, 15 Apr 2021 16:39:59 +0800 Message-Id: <20210415084005.25049-4-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20210415084005.25049-1-songmuchun@bytedance.com> References: <20210415084005.25049-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@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. Signed-off-by: Muchun Song Reviewed-by: Oscar Salvador Reviewed-by: Miaohe Lin Tested-by: Chen Huang Tested-by: Bodeddula Balasubramaniam Acked-by: Michal Hocko --- include/linux/hugetlb.h | 21 +++++++++++++++++++-- include/linux/hugetlb_cgroup.h | 19 +++++++++++-------- 2 files changed, 30 insertions(+), 10 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 09f1fd12a6fa..0abed7e766b8 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -29,6 +29,23 @@ typedef struct { unsigned long pd; } hugepd_t; #include #include +/* + * 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 gather these discrete indexes + * of tail struct page here. + */ +enum { + SUBPAGE_INDEX_SUBPOOL = 1, /* reuse page->private */ +#ifdef CONFIG_CGROUP_HUGETLB + SUBPAGE_INDEX_CGROUP, /* reuse page->private */ + SUBPAGE_INDEX_CGROUP_RSVD, /* reuse page->private */ + __MAX_CGROUP_SUBPAGE_INDEX = SUBPAGE_INDEX_CGROUP_RSVD, +#endif + __NR_USED_SUBPAGE, +}; + struct hugepage_subpool { spinlock_t lock; long count; @@ -626,13 +643,13 @@ extern unsigned int default_hstate_idx; */ static inline struct hugepage_subpool *hugetlb_page_subpool(struct page *hpage) { - return (struct hugepage_subpool *)(hpage+1)->private; + return (void *)page_private(hpage + SUBPAGE_INDEX_SUBPOOL); } static inline void hugetlb_set_page_subpool(struct page *hpage, struct hugepage_subpool *subpool) { - set_page_private(hpage+1, (unsigned long)subpool); + set_page_private(hpage + SUBPAGE_INDEX_SUBPOOL, (unsigned long)subpool); } static inline struct hstate *hstate_file(struct file *f) diff --git a/include/linux/hugetlb_cgroup.h b/include/linux/hugetlb_cgroup.h index 0bff345c4bc6..0b8d1fdda3a1 100644 --- a/include/linux/hugetlb_cgroup.h +++ b/include/linux/hugetlb_cgroup.h @@ -21,15 +21,16 @@ struct hugetlb_cgroup; struct resv_map; struct file_region; +#ifdef CONFIG_CGROUP_HUGETLB /* * 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 +#define HUGETLB_CGROUP_MIN_ORDER order_base_2(__MAX_CGROUP_SUBPAGE_INDEX + 1) -#ifdef CONFIG_CGROUP_HUGETLB enum hugetlb_memory_event { HUGETLB_MAX, HUGETLB_NR_MEMORY_EVENTS, @@ -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; } -- 2.11.0