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 49931C56201 for ; Tue, 24 Nov 2020 09:58:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD9B120637 for ; Tue, 24 Nov 2020 09:58:19 +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="FwWSJi2c" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731715AbgKXJ6I (ORCPT ); Tue, 24 Nov 2020 04:58:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731706AbgKXJ6H (ORCPT ); Tue, 24 Nov 2020 04:58:07 -0500 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39FEFC061A4D for ; Tue, 24 Nov 2020 01:58:07 -0800 (PST) Received: by mail-pf1-x443.google.com with SMTP id b6so7547877pfp.7 for ; Tue, 24 Nov 2020 01:58:07 -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=BbFCNgyPE8nizGGDJDZBGUHg6UO+mJRBaj4BfE6x8So=; b=FwWSJi2cHVLIvbiOkLH6oUoM/YtuKQ9XtRGesAdYMI8WK/9ZQRRLTsMwEun+e1dW4R WJf3KMSYagwqAkOJl39z+uBWiCKjtOVdYqd84WGW33xAGCtWyyZ2MZhj6ghdETJ5mX9W pk+kX0lq3SP2kWM2s9gwaHeBiQtgXFDcMw4o+CygYAAuqpgs1ZY+czuXaEoAnUX7ob8x 0ldPerB5AR0kLOKkKWUacv2367EhY1Wp1ejTVHv9/y31UF1L6b2arv+hIs4WcRP8FpDG WRmEK1V0zzx4XPrAM9G0UE8kTphJnNhaheePBt+e/IPjR7xKioUsJnKUfFwtm9y6vAJT JtTg== 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=BbFCNgyPE8nizGGDJDZBGUHg6UO+mJRBaj4BfE6x8So=; b=e6Fs5i6xygmyAenlMJ0moPpcvyfh31jqzqISTanDp4Cuzi8MrSs6VuhxSzoYLoHv+o hUg0pOnOjHS/SoG/VWKwTHUvof6MpXYsZwaKDeUQRrVC6rNyBgaT7wMQX9Bk3qPJWcDg c3xMrvCXnG66GtZkwY+VULpKkJgRAOUXY+28kC4c96EJfPtMHLCq0Sim44UI3IP6Hdk+ wVR3eQSGYVTmhiNFg2fT1WnjIioTccZeb3If6T+rAWWC8/VFXoff7mpaoFFbggUhvWNa TP9+a1ugRrm2JBBJJIRGpNi6wDIviFAMQYTGm8y7OEFiFlL2+sEYhsSQrM9KaW/vONHY YIEw== X-Gm-Message-State: AOAM530ST3zgrGzXe0GEEqj/OMkiHz3fAJr+IH8wQx8xrx5xTHDLFq+p dkt5l1DgIfcVRRQW/iL9G7vKXw== X-Google-Smtp-Source: ABdhPJwX9HQ0VjDIqeOVrfmO9iIZzoKa4yniFwFtNwTWpg2A7NszkjO8GLva5IH0THXOXslntQZcCQ== X-Received: by 2002:a17:90a:fd0e:: with SMTP id cv14mr3877515pjb.182.1606211886807; Tue, 24 Nov 2020 01:58:06 -0800 (PST) Received: from localhost.localdomain ([103.136.220.120]) by smtp.gmail.com with ESMTPSA id t20sm2424562pjg.25.2020.11.24.01.57.56 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Nov 2020 01:58:06 -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 v6 08/16] mm/hugetlb: Free the vmemmap pages associated with each hugetlb page Date: Tue, 24 Nov 2020 17:52:51 +0800 Message-Id: <20201124095259.58755-9-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201124095259.58755-1-songmuchun@bytedance.com> References: <20201124095259.58755-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When we allocate a hugetlb page from the buddy, we should free the unused vmemmap pages associated with it. We can do that in the prep_new_huge_page(). Signed-off-by: Muchun Song --- arch/x86/include/asm/pgtable_64_types.h | 8 ++ mm/hugetlb.c | 2 + mm/hugetlb_vmemmap.c | 133 +++++++++++++++++++++++++++++++- mm/hugetlb_vmemmap.h | 5 ++ 4 files changed, 147 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 52e5f5f2240d..bedbd2e7d06c 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -139,6 +139,14 @@ extern unsigned int ptrs_per_p4d; # define VMEMMAP_START __VMEMMAP_BASE_L4 #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */ +/* + * VMEMMAP_SIZE - allows the whole linear region to be covered by + * a struct page array. + */ +#define VMEMMAP_SIZE (1UL << (__VIRTUAL_MASK_SHIFT - PAGE_SHIFT - \ + 1 + ilog2(sizeof(struct page)))) +#define VMEMMAP_END (VMEMMAP_START + VMEMMAP_SIZE) + #define VMALLOC_END (VMALLOC_START + (VMALLOC_SIZE_TB << 40) - 1) #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f88032c24667..9662b5535f3a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1499,6 +1499,8 @@ void free_huge_page(struct page *page) static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) { + free_huge_page_vmemmap(h, page); + INIT_LIST_HEAD(&page->lru); set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); set_hugetlb_cgroup(page, NULL); diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index fd60cfdf3d40..1576f69bd1d3 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -92,8 +92,9 @@ * to the 2MB HugeTLB page. We also can use this approach to free the vmemmap * pages. */ -#define pr_fmt(fmt) "HugeTLB Vmemmap: " fmt +#define pr_fmt(fmt) "HugeTLB vmemmap: " fmt +#include #include "hugetlb_vmemmap.h" /* @@ -105,6 +106,136 @@ * these page frames. Therefore, we need to reserve two pages as vmemmap areas. */ #define RESERVE_VMEMMAP_NR 2U +#define RESERVE_VMEMMAP_SIZE (RESERVE_VMEMMAP_NR << PAGE_SHIFT) +#define TAIL_PAGE_REUSE -1 + +#ifndef VMEMMAP_HPAGE_SHIFT +#define VMEMMAP_HPAGE_SHIFT HPAGE_SHIFT +#endif +#define VMEMMAP_HPAGE_ORDER (VMEMMAP_HPAGE_SHIFT - PAGE_SHIFT) +#define VMEMMAP_HPAGE_NR (1 << VMEMMAP_HPAGE_ORDER) +#define VMEMMAP_HPAGE_SIZE ((1UL) << VMEMMAP_HPAGE_SHIFT) +#define VMEMMAP_HPAGE_MASK (~(VMEMMAP_HPAGE_SIZE - 1)) + +#define vmemmap_hpage_addr_end(addr, end) \ +({ \ + unsigned long __boundary; \ + __boundary = ((addr) + VMEMMAP_HPAGE_SIZE) & VMEMMAP_HPAGE_MASK; \ + (__boundary - 1 < (end) - 1) ? __boundary : (end); \ +}) + +static inline unsigned int free_vmemmap_pages_per_hpage(struct hstate *h) +{ + return h->nr_free_vmemmap_pages; +} + +static inline unsigned int vmemmap_pages_per_hpage(struct hstate *h) +{ + return free_vmemmap_pages_per_hpage(h) + RESERVE_VMEMMAP_NR; +} + +static inline unsigned long vmemmap_pages_size_per_hpage(struct hstate *h) +{ + return (unsigned long)vmemmap_pages_per_hpage(h) << PAGE_SHIFT; +} + +/* + * Walk a vmemmap address to the pmd it maps. + */ +static pmd_t *vmemmap_to_pmd(unsigned long page) +{ + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + + if (page < VMEMMAP_START || page >= VMEMMAP_END) + return NULL; + + pgd = pgd_offset_k(page); + if (pgd_none(*pgd)) + return NULL; + p4d = p4d_offset(pgd, page); + if (p4d_none(*p4d)) + return NULL; + pud = pud_offset(p4d, page); + if (pud_none(*pud) || pud_bad(*pud)) + return NULL; + + return pmd_offset(pud, page); +} + +static inline void free_vmemmap_page_list(struct list_head *list) +{ + struct page *page, *next; + + list_for_each_entry_safe(page, next, list, lru) { + list_del(&page->lru); + free_vmemmap_page(page); + } +} + +static void __free_huge_page_pte_vmemmap(struct page *reuse, pte_t *ptep, + unsigned long start, + unsigned long end, + struct list_head *free_pages) +{ + /* Make the tail pages are mapped read-only. */ + pgprot_t pgprot = PAGE_KERNEL_RO; + pte_t entry = mk_pte(reuse, pgprot); + unsigned long addr; + + for (addr = start; addr < end; addr += PAGE_SIZE, ptep++) { + struct page *page; + pte_t old = *ptep; + + VM_WARN_ON(!pte_present(old)); + page = pte_page(old); + list_add(&page->lru, free_pages); + + set_pte_at(&init_mm, addr, ptep, entry); + } +} + +static void __free_huge_page_pmd_vmemmap(pmd_t *pmd, unsigned long start, + unsigned long end, + struct list_head *vmemmap_pages) +{ + unsigned long next, addr = start; + struct page *reuse = NULL; + + do { + pte_t *ptep; + + ptep = pte_offset_kernel(pmd, addr); + if (!reuse) + reuse = pte_page(ptep[TAIL_PAGE_REUSE]); + + next = vmemmap_hpage_addr_end(addr, end); + __free_huge_page_pte_vmemmap(reuse, ptep, addr, next, + vmemmap_pages); + } while (pmd++, addr = next, addr != end); + + flush_tlb_kernel_range(start, end); +} + +void free_huge_page_vmemmap(struct hstate *h, struct page *head) +{ + pmd_t *pmd; + unsigned long start, end; + unsigned long vmemmap_addr = (unsigned long)head; + LIST_HEAD(free_pages); + + if (!free_vmemmap_pages_per_hpage(h)) + return; + + pmd = vmemmap_to_pmd(vmemmap_addr); + BUG_ON(!pmd); + + start = vmemmap_addr + RESERVE_VMEMMAP_SIZE; + end = vmemmap_addr + vmemmap_pages_size_per_hpage(h); + __free_huge_page_pmd_vmemmap(pmd, start, end, &free_pages); + free_vmemmap_page_list(&free_pages); +} void __init hugetlb_vmemmap_init(struct hstate *h) { diff --git a/mm/hugetlb_vmemmap.h b/mm/hugetlb_vmemmap.h index 40c0c7dfb60d..67113b67495f 100644 --- a/mm/hugetlb_vmemmap.h +++ b/mm/hugetlb_vmemmap.h @@ -12,9 +12,14 @@ #ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP void __init hugetlb_vmemmap_init(struct hstate *h); +void free_huge_page_vmemmap(struct hstate *h, struct page *head); #else static inline void hugetlb_vmemmap_init(struct hstate *h) { } + +static inline void free_huge_page_vmemmap(struct hstate *h, struct page *head) +{ +} #endif /* CONFIG_HUGETLB_PAGE_FREE_VMEMMAP */ #endif /* _LINUX_HUGETLB_VMEMMAP_H */ -- 2.11.0