From patchwork Mon Nov 30 15:18:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 11940825 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=ham 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 46415C83018 for ; Mon, 30 Nov 2020 15:21:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F1F702222A for ; Mon, 30 Nov 2020 15:21:49 +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="KHj6urA7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728065AbgK3PVo (ORCPT ); Mon, 30 Nov 2020 10:21:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728051AbgK3PVn (ORCPT ); Mon, 30 Nov 2020 10:21:43 -0500 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9731DC061A49 for ; Mon, 30 Nov 2020 07:21:03 -0800 (PST) Received: by mail-pl1-x643.google.com with SMTP id l11so6668773plt.1 for ; Mon, 30 Nov 2020 07:21:03 -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=GJFpo+N04VqrewLjKp497y8U/hKK302CXBHn7zde7rI=; b=KHj6urA7j1PhhYBctDr/dZ2Y8+YdAZv4Scnb4CDja0LAt97BQSSAuzY01M8UHt0M6B D7wYUPj87q3dODiwYx/yDEjxrYrzsGH9XNp8UvtXG2EKFEL4MPvtbsX0aBwXGwg9myO/ 1zEvElFKGBPVTxxY07QXI5nNlF71M291SU64zE026lgD155JPixh96/+5m3h8Dt8+Rj+ +RxpzVljged5iaxILF3K1X2K/xKRIkT6mND652JE8GhjQQUhQ+ftSBN9t4E5LKK86sXm Oa8ssYo22OoQkQ/+8qes4F8asp/9svJgjt4bukIttRevzagDAs+uN04DlpjWXLcSp2pb cvnw== 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=GJFpo+N04VqrewLjKp497y8U/hKK302CXBHn7zde7rI=; b=tCMSQXzpvc0cL/8j33iKHdZ3BIyDCRLByjz7MJ5QfRv9hms8CdtmnGiXa2DiX0AMbo t92q6IoprMLpxViJwq1FaRCfmlRGV1yjZRvzc7SO4goFLMoHR3NPoQ9Qx1ViP+juDadM yBwKMasDnhK1gZHULfTYcDTrecsSHDy4kf7MouThp4trAyGYBaua90rBBgdAS6urdkyW GJRzmYrtvdrGmniw2qXvFnqkE9uYU8uKlhnGnpyUD8vCtj3DINlntYX58LJsw4Nwnve4 i37IN6mgxp1j2c2W212aHjOTw9OhKxa43+60mb6wTQb37mRONxCfF3dpgI+xaYPd2S0A NCIw== X-Gm-Message-State: AOAM531A5RjXkk6iuS1qraQeR9NfsPjEmW1Py19heAiWnMz2I4k68YG8 soYU+hpNY97BdyzTFDgdpZt52Q== X-Google-Smtp-Source: ABdhPJyxyjfnLNNhfGWHO3IAw/j3oVwIH6eKTJibyAajhJkdBkpv3vkc/jD3PRaax5IuIkX+VB5dMQ== X-Received: by 2002:a17:90a:8412:: with SMTP id j18mr27244952pjn.124.1606749663162; Mon, 30 Nov 2020 07:21:03 -0800 (PST) Received: from localhost.bytedance.net ([103.136.221.68]) by smtp.gmail.com with ESMTPSA id q12sm16201660pgv.91.2020.11.30.07.20.53 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 30 Nov 2020 07:21:02 -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 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 v7 10/15] mm/hugetlb: Allocate the vmemmap pages associated with each hugetlb page Date: Mon, 30 Nov 2020 23:18:33 +0800 Message-Id: <20201130151838.11208-11-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201130151838.11208-1-songmuchun@bytedance.com> References: <20201130151838.11208-1-songmuchun@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org When we free a hugetlb page to the buddy, we should allocate the vmemmap pages associated with it. We can do that in the __free_hugepage(). Signed-off-by: Muchun Song --- mm/hugetlb.c | 2 ++ mm/hugetlb_vmemmap.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++--- mm/hugetlb_vmemmap.h | 5 +++ 3 files changed, 92 insertions(+), 5 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 5131ae3d2245..ebe35532d432 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1381,6 +1381,8 @@ static void __free_hugepage(struct hstate *h, struct page *page) { int i; + alloc_huge_page_vmemmap(h, page); + for (i = 0; i < pages_per_huge_page(h); i++) { page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 1 << PG_referenced | 1 << PG_dirty | diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index af42fad1f131..a3714db7f400 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -95,6 +95,7 @@ #define pr_fmt(fmt) "HugeTLB vmemmap: " fmt #include +#include #include "hugetlb_vmemmap.h" /* @@ -108,6 +109,8 @@ #define RESERVE_VMEMMAP_NR 2U #define RESERVE_VMEMMAP_SIZE (RESERVE_VMEMMAP_NR << PAGE_SHIFT) #define VMEMMAP_TAIL_PAGE_REUSE -1 +#define GFP_VMEMMAP_PAGE \ + (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_HIGH) #ifndef VMEMMAP_HPAGE_SHIFT #define VMEMMAP_HPAGE_SHIFT HPAGE_SHIFT @@ -124,6 +127,11 @@ (__boundary - 1 < (end) - 1) ? __boundary : (end); \ }) +typedef void (*vmemmap_remap_pte_func_t)(struct page *reuse, pte_t *pte, + unsigned long start, unsigned long end, + void *priv); + + static inline unsigned int vmemmap_pages_per_hpage(struct hstate *h) { return free_vmemmap_pages_per_hpage(h) + RESERVE_VMEMMAP_NR; @@ -163,9 +171,40 @@ static pmd_t *vmemmap_to_pmd(unsigned long addr) return pmd; } +static void vmemmap_restore_pte_range(struct page *reuse, pte_t *pte, + unsigned long start, unsigned long end, + void *priv) +{ + pgprot_t pgprot = PAGE_KERNEL; + void *from = page_to_virt(reuse); + unsigned long addr; + struct list_head *pages = priv; + + for (addr = start; addr < end; addr += PAGE_SIZE) { + void *to; + struct page *page; + + VM_BUG_ON(pte_none(*pte) || pte_page(*pte) != reuse); + + page = list_first_entry(pages, struct page, lru); + list_del(&page->lru); + to = page_to_virt(page); + copy_page(to, from); + + /* + * Make sure that any data that writes to the @to is made + * visible to the physical page. + */ + flush_kernel_vmap_range(to, PAGE_SIZE); + + prepare_vmemmap_page(page); + set_pte_at(&init_mm, addr, pte++, mk_pte(page, pgprot)); + } +} + static void vmemmap_reuse_pte_range(struct page *reuse, pte_t *pte, unsigned long start, unsigned long end, - struct list_head *vmemmap_pages) + void *priv) { /* * Make the tail pages are mapped with read-only to catch @@ -174,6 +213,7 @@ static void vmemmap_reuse_pte_range(struct page *reuse, pte_t *pte, pgprot_t pgprot = PAGE_KERNEL_RO; pte_t entry = mk_pte(reuse, pgprot); unsigned long addr; + struct list_head *pages = priv; for (addr = start; addr < end; addr += PAGE_SIZE, pte++) { struct page *page; @@ -181,14 +221,14 @@ static void vmemmap_reuse_pte_range(struct page *reuse, pte_t *pte, VM_BUG_ON(pte_none(*pte)); page = pte_page(*pte); - list_add(&page->lru, vmemmap_pages); + list_add(&page->lru, pages); set_pte_at(&init_mm, addr, pte, entry); } } static void vmemmap_remap_range(unsigned long start, unsigned long end, - struct list_head *vmemmap_pages) + vmemmap_remap_pte_func_t func, void *priv) { pmd_t *pmd; unsigned long next, addr = start; @@ -208,12 +248,52 @@ static void vmemmap_remap_range(unsigned long start, unsigned long end, reuse = pte_page(pte[VMEMMAP_TAIL_PAGE_REUSE]); next = vmemmap_hpage_addr_end(addr, end); - vmemmap_reuse_pte_range(reuse, pte, addr, next, vmemmap_pages); + func(reuse, pte, addr, next, priv); } while (pmd++, addr = next, addr != end); flush_tlb_kernel_range(start, end); } +static inline void alloc_vmemmap_pages(struct hstate *h, struct list_head *list) +{ + unsigned int nr = free_vmemmap_pages_per_hpage(h); + + while (nr--) { + struct page *page; + +retry: + page = alloc_page(GFP_VMEMMAP_PAGE); + if (unlikely(!page)) { + msleep(100); + /* + * We should retry infinitely, because we cannot + * handle allocation failures. Once we allocate + * vmemmap pages successfully, then we can free + * a HugeTLB page. + */ + goto retry; + } + list_add_tail(&page->lru, list); + } +} + +void alloc_huge_page_vmemmap(struct hstate *h, struct page *head) +{ + unsigned long start, end; + unsigned long vmemmap_addr = (unsigned long)head; + LIST_HEAD(vmemmap_pages); + + if (!free_vmemmap_pages_per_hpage(h)) + return; + + alloc_vmemmap_pages(h, &vmemmap_pages); + + start = vmemmap_addr + RESERVE_VMEMMAP_SIZE; + end = vmemmap_addr + vmemmap_pages_size_per_hpage(h); + vmemmap_remap_range(start, end, vmemmap_restore_pte_range, + &vmemmap_pages); +} + static inline void free_vmemmap_page_list(struct list_head *list) { struct page *page, *next; @@ -235,7 +315,7 @@ void free_huge_page_vmemmap(struct hstate *h, struct page *head) start = vmemmap_addr + RESERVE_VMEMMAP_SIZE; end = vmemmap_addr + vmemmap_pages_size_per_hpage(h); - vmemmap_remap_range(start, end, &vmemmap_pages); + vmemmap_remap_range(start, end, vmemmap_reuse_pte_range, &vmemmap_pages); free_vmemmap_page_list(&vmemmap_pages); } diff --git a/mm/hugetlb_vmemmap.h b/mm/hugetlb_vmemmap.h index 293897b9f1d8..7887095488f4 100644 --- a/mm/hugetlb_vmemmap.h +++ b/mm/hugetlb_vmemmap.h @@ -12,6 +12,7 @@ #ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP void __init hugetlb_vmemmap_init(struct hstate *h); +void alloc_huge_page_vmemmap(struct hstate *h, struct page *head); void free_huge_page_vmemmap(struct hstate *h, struct page *head); static inline unsigned int free_vmemmap_pages_per_hpage(struct hstate *h) @@ -23,6 +24,10 @@ static inline void hugetlb_vmemmap_init(struct hstate *h) { } +static inline void alloc_huge_page_vmemmap(struct hstate *h, struct page *head) +{ +} + static inline void free_huge_page_vmemmap(struct hstate *h, struct page *head) { }