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,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 092BFC433DB for ; Sun, 17 Jan 2021 15:17:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CF5E122460 for ; Sun, 17 Jan 2021 15:17:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729350AbhAQPQm (ORCPT ); Sun, 17 Jan 2021 10:16:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38284 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729584AbhAQPPy (ORCPT ); Sun, 17 Jan 2021 10:15:54 -0500 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3EE1C06179A for ; Sun, 17 Jan 2021 07:15:08 -0800 (PST) Received: by mail-pf1-x434.google.com with SMTP id j12so1521498pfj.12 for ; Sun, 17 Jan 2021 07:15:08 -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=leMCwiJUMOALRI5sultiZwFK5v4LdPgwOBvUXqzpH+M=; b=nU947GUBl5gNEwin/Dh5khj/oNK7YocifknATbfcT2PQvf7wzkSL2i6ac0RWNMcswJ Qx9QJkfu5r/pQ7szUy775TQPy5EYJmymzC4qqeBhixQbfrtgPUktVp0kRD17Ri4XG+4J rFJZmd9tnAuk3hx+ll4HmwdZo6uF07W1TaOuGWE4131eUzOEOT/wPOHoTn9/3BgFsoBD NCvpEwEJMtD/6JLkB8zj6uSHx5rbDo6arnxQMWYoygDiNYrii79NFNrRhjzxLaOJoiZB EmB3Sqvobb4k/AvAem+aG5Crop1DkzAosxPSsCTPLN8ffvz62UC2MmSITreWPt793E89 z9mA== 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=leMCwiJUMOALRI5sultiZwFK5v4LdPgwOBvUXqzpH+M=; b=YdPSTCUT8U+G4p/anHZScBbAn/sTI7ekAgxn1cIcyXSQ8sZWDJXr+69vGxLCoVVdId AJlW+sHhawPnpyMazXXeE/XFER+/BmKEPnWecoQ1kM2No/XErgVuZwRAX4DgtK3EFV5r wbURDAz8yLa3htPdwSjt1/Ayh5luAiiUkIhXEzcQ5SSjjSf+VKFAhmDRw2wZhf/aQGTY wxQlQWNtE0gObAUPPTl6zgzyyPs3JQ44vu4gTQOPXNZGQcI4EBsg/s3IDTHSKjdE3Y9h mxMEDruAJuUX7K3K8AF+/3RHhHmXO34LLcoEUO2y2UkXa2Y0bwdV83hDJdWRPiEAA5Nc D/Ig== X-Gm-Message-State: AOAM530RDtS0/N+ssLSxLWX/mKucZZ6HSzAk1dTAauISmup1IuYTwOXP EppYBEdC5vNj/dgOXWz5cTeeNQ== X-Google-Smtp-Source: ABdhPJwKE9KZZq+vF8UdJn0d8va2uhh4pytapUNaWVa6FNjoKs5iqgjgPpbCtvxqTymHRujF1jknNg== X-Received: by 2002:aa7:83cd:0:b029:1a5:fb23:ad7f with SMTP id j13-20020aa783cd0000b02901a5fb23ad7fmr22184733pfn.46.1610896508537; Sun, 17 Jan 2021 07:15:08 -0800 (PST) Received: from localhost.bytedance.net ([139.177.225.247]) by smtp.gmail.com with ESMTPSA id i22sm9247915pjv.35.2021.01.17.07.14.54 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 17 Jan 2021 07:15:08 -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 v13 08/12] mm: hugetlb: introduce PageHugeInflight Date: Sun, 17 Jan 2021 23:10:49 +0800 Message-Id: <20210117151053.24600-9-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20210117151053.24600-1-songmuchun@bytedance.com> References: <20210117151053.24600-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org When we free a HugeTLB page whose vmemmap pages can be optimized, it is freed to the buddy allocator through a kworker. And the ref count of page is zero, so if we dissolve it before it is freed to the buddy allocator. It can be freed again. In order to avoid this, we introduce PageHugeInflight to indicate that the HugeTLB page is already freed from hugepage pool but not freed to buddy allocator yet. When we hit the inflight page, we just need to flush the work. Signed-off-by: Muchun Song --- mm/hugetlb.c | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3222bad8b112..14549204ddcb 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1343,6 +1343,36 @@ static inline void flush_hpage_update_work(struct hstate *h) flush_work(&hpage_update_work); } +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP +static inline bool PageHugeInflight(struct page *head) +{ + return page_private(head + 5) == -1UL; +} + +static inline void SetPageHugeInflight(struct page *head) +{ + set_page_private(head + 5, -1UL); +} + +static inline void ClearPageHugeInflight(struct page *head) +{ + set_page_private(head + 5, 0); +} +#else +static inline bool PageHugeInflight(struct page *head) +{ + return false; +} + +static inline void SetPageHugeInflight(struct page *head) +{ +} + +static inline void ClearPageHugeInflight(struct page *head) +{ +} +#endif + static inline void __update_and_free_page(struct hstate *h, struct page *page) { /* No need to allocate vmemmap pages */ @@ -1351,6 +1381,8 @@ static inline void __update_and_free_page(struct hstate *h, struct page *page) return; } + SetPageHugeInflight(page); + /* * Defer freeing to avoid using GFP_ATOMIC to allocate vmemmap * pages. @@ -1637,6 +1669,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) { free_huge_page_vmemmap(h, page); + ClearPageHugeInflight(page); INIT_LIST_HEAD(&page->lru); set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); set_hugetlb_cgroup(page, NULL); @@ -1913,13 +1946,16 @@ int dissolve_free_huge_page(struct page *page) if (h->free_huge_pages - h->resv_huge_pages == 0) goto out; + rc = 0; hwpoison_subpage_set(h, head, page); + if (PageHugeInflight(head)) + goto out; + list_del(&head->lru); h->free_huge_pages--; h->free_huge_pages_node[nid]--; h->max_huge_pages--; update_and_free_page(h, head); - rc = 0; } out: spin_unlock(&hugetlb_lock); -- 2.11.0