From patchwork Fri Nov 13 10:59:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 11903043 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1DF32138B for ; Fri, 13 Nov 2020 11:07:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD6BA2137B for ; Fri, 13 Nov 2020 11:07:49 +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="hgVW5dqk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726630AbgKMLHl (ORCPT ); Fri, 13 Nov 2020 06:07:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726443AbgKMLFw (ORCPT ); Fri, 13 Nov 2020 06:05:52 -0500 Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F79BC09424B for ; Fri, 13 Nov 2020 03:04:34 -0800 (PST) Received: by mail-pg1-x542.google.com with SMTP id f27so6831221pgl.1 for ; Fri, 13 Nov 2020 03:04:34 -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=q+VtCLDnL2Xa2mKU9/pdAYc0VFam3D1bbZtkQW1vxCY=; b=hgVW5dqkMQlyxy+pm08vW0Vd4PTnyXbalrCOkkce5dt2d7VoBxu3eV1+af7yino6+6 cGORVLq1cSX0r2YA/O/gfxdClSiPYIYUmP+R2rEBhSknBmWIxKIZ3QrN1xE/O3Bl8BAD dne9R+uc5fjS1f+S/hTh2/DMUQaxpq6G1hj5sWcyOTa2aaW4weditA2SU1YHChizvM5O QsA3ug8vIl0Mhx6DwWu2jjJU5ozuPlMxamPpzHj8yVFvS7TflofJtxQbUcoFAyKq0rwr 6FtSlJW7HhROiINTFTjqs1TiqwwHpu91rRIWgVglPqRJ7o3j8fcW9b/0TVj05DGoe76S zuJA== 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=q+VtCLDnL2Xa2mKU9/pdAYc0VFam3D1bbZtkQW1vxCY=; b=C7mszQ1QqX99A71h0q2Ib2uflMoA0lgx2Jqby1ZRFisJZ0OXiu1nKoVyiQQ+Bq7E0G 8ZWSLq341ZZrR1vAJqXAw9xlkm5OkQp6AVslI3jZwLjJOl6OnvBUcTTKJS9u1t3tOTjV QZiuO4QlM7UNT3DaMjGe+P7QYojrmg3ZFiUJLW1q69yv6c4w97AxNpNE4RdMU0q67mn3 uYhK61+riO5zv9PQRy6j2OwkHd+UiSmUS2dTAtNM/wOSwdd60krjoBzK0ckmgFXlBrDk M/IblLjoim9qwjH2TQK6l/zEiB/viPNcBSGJwaJhxImNKbDOvpMWuAFTdV6hdV0cvAV+ pB8g== X-Gm-Message-State: AOAM5319ogIaPPweb2vilSlC/7/ovar9jGJPZS4HsyoadNl+GbitvtsV rN5R4UEA3vJhfxJWHl1CnSsPtg== X-Google-Smtp-Source: ABdhPJwfPxpTm7KDY6rcrwOeaIhwRPV0v2rdEjxMNJn3NT0L5sknMy457PQCHIEbzp6HKN47tm1isA== X-Received: by 2002:a17:90b:1058:: with SMTP id gq24mr2370569pjb.29.1605265473882; Fri, 13 Nov 2020 03:04:33 -0800 (PST) Received: from localhost.localdomain ([61.120.150.78]) by smtp.gmail.com with ESMTPSA id f1sm8909959pfc.56.2020.11.13.03.04.20 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Nov 2020 03:04:33 -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 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 v4 19/21] mm/hugetlb: Gather discrete indexes of tail page Date: Fri, 13 Nov 2020 18:59:50 +0800 Message-Id: <20201113105952.11638-20-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201113105952.11638-1-songmuchun@bytedance.com> References: <20201113105952.11638-1-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. Signed-off-by: Muchun Song --- include/linux/hugetlb.h | 13 +++++++++++++ include/linux/hugetlb_cgroup.h | 15 +++++++++------ mm/hugetlb.c | 12 ++++++------ mm/hugetlb_vmemmap.h | 4 ++-- 4 files changed, 30 insertions(+), 14 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index da18fc9ed152..fa9d38a3ac6f 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 9aad0b63d369..dfa982f4b525 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1429,20 +1429,20 @@ 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]); } /* @@ -1454,17 +1454,17 @@ 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.h b/mm/hugetlb_vmemmap.h index b09fd658ce20..86d80c7f1dc7 100644 --- a/mm/hugetlb_vmemmap.h +++ b/mm/hugetlb_vmemmap.h @@ -26,7 +26,7 @@ static inline void subpage_hwpoison_deliver(struct page *head) struct page *page = head; if (PageHWPoison(head)) - 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, @@ -41,7 +41,7 @@ static inline void subpage_hwpoison_deliver(struct page *head) static inline void set_subpage_hwpoison(struct page *head, struct page *page) { if (PageHWPoison(head)) - set_page_private(head + 4, page - head); + set_page_private(head + SUBPAGE_INDEX_HWPOISON, page - head); } static inline unsigned int free_vmemmap_pages_per_hpage(struct hstate *h)