From patchwork Sun Jan 17 15:10:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 12025507 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 0346CC433E0 for ; Sun, 17 Jan 2021 15:17:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB80E22460 for ; Sun, 17 Jan 2021 15:17:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729636AbhAQPRB (ORCPT ); Sun, 17 Jan 2021 10:17:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729570AbhAQPPs (ORCPT ); Sun, 17 Jan 2021 10:15:48 -0500 Received: from mail-pl1-x630.google.com (mail-pl1-x630.google.com [IPv6:2607:f8b0:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFACCC061799 for ; Sun, 17 Jan 2021 07:14:54 -0800 (PST) Received: by mail-pl1-x630.google.com with SMTP id g3so7239066plp.2 for ; Sun, 17 Jan 2021 07:14:54 -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=dASYKFPFHjiUnTmEMcq8ifWiWDwHax4a4AuznfbkXhg=; b=fWMqIgVimAbohcSo2EpgXsd0ZyJcaZzla1+P95eOMhnyBL67qm5KAucfNimJ/Y8PPb 6lF03rRUJiEGIKgB/d1AF+BsYCsr8ZT/Pkx2QnCiOzg30HL6dN6laFtm47lJUIMes242 fLMU5PBdfikWpoU3XtBfxGbxS21r+dNKUIs0erFDXDnITMS6DorxcHLayrDhExX+u1kd LKu1pnMupUMbBV/W81fmIsxl2VIip0Rjx4irqQjbsT4/3aLaB+AP+zMyGWoJlzg4xCTQ XUmjXCkW9w6/ar5htk+JxAIb65JCm2a9ZELvCKmKVdv+ntoLKXK7+b4P7Ny7qpDyk5jR /pZg== 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=dASYKFPFHjiUnTmEMcq8ifWiWDwHax4a4AuznfbkXhg=; b=V1+x6i7GwgMnuYdlqqFC+UJOBubt+wMDSg4Q5p3/oxQ+lFG1fNGvMoTh/v2D/YfgOO 8cbh/fb9X+I4Q68ddGi37Xgr9JUVoeSrWEK4+BerHA2WKWokx96XFAL46rnOGhCTIlPJ o3fx1q+RHvmoWTLywdDmInE04W5JnsV37GrrWp0qxRZvr9q8R5z8g2h0GSXHnXhnZ+2o wOI0QFMoU1tgGnf6Fay2nIlV9MSvrc2gr+jfn+TW3iRXLjSAfEfJFNumx0wApaor0thx VFSDh7hkteiEuPrNXCfP8OoBOCC/abe0T7Pb959qe/P/Gi5hTo/R1UIHo1knCCkgXKho zNlQ== X-Gm-Message-State: AOAM531PUiVubOxld1dFaFoPdwD7U58udLUS9EXCXQbZxox2YvbRAbCI orB+T0WnLPKbA9oTK6CQsAxkVg== X-Google-Smtp-Source: ABdhPJyLwFkAudGuCIo1upuVxlqgazAYTsuwjbaVLNbfgDm7FzQG69F7R66FSfzEmpPd+yF9XBCLig== X-Received: by 2002:a17:90a:df84:: with SMTP id p4mr21024876pjv.81.1610896494542; Sun, 17 Jan 2021 07:14:54 -0800 (PST) Received: from localhost.bytedance.net ([139.177.225.247]) by smtp.gmail.com with ESMTPSA id i22sm9247915pjv.35.2021.01.17.07.14.41 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 17 Jan 2021 07:14:54 -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 07/12] mm: hugetlb: flush work when dissolving a HugeTLB page Date: Sun, 17 Jan 2021 23:10:48 +0800 Message-Id: <20210117151053.24600-8-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org We should flush work when dissolving a HugeTLB page to make sure that the HugeTLB page is freed to the buddy allocator. Because the caller of dissolve_free_huge_pages() relies on this guarantee. Signed-off-by: Muchun Song Reviewed-by: Oscar Salvador --- mm/hugetlb.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 6caaa7e5dd2a..3222bad8b112 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1337,6 +1337,12 @@ static void update_hpage_vmemmap_workfn(struct work_struct *work) } static DECLARE_WORK(hpage_update_work, update_hpage_vmemmap_workfn); +static inline void flush_hpage_update_work(struct hstate *h) +{ + if (free_vmemmap_pages_per_hpage(h)) + flush_work(&hpage_update_work); +} + static inline void __update_and_free_page(struct hstate *h, struct page *page) { /* No need to allocate vmemmap pages */ @@ -1887,6 +1893,7 @@ static int free_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, int dissolve_free_huge_page(struct page *page) { int rc = -EBUSY; + struct hstate *h = NULL; /* Not to disrupt normal path by vainly holding hugetlb_lock */ if (!PageHuge(page)) @@ -1900,8 +1907,9 @@ int dissolve_free_huge_page(struct page *page) if (!page_count(page)) { struct page *head = compound_head(page); - struct hstate *h = page_hstate(head); int nid = page_to_nid(head); + + h = page_hstate(head); if (h->free_huge_pages - h->resv_huge_pages == 0) goto out; @@ -1915,6 +1923,14 @@ int dissolve_free_huge_page(struct page *page) } out: spin_unlock(&hugetlb_lock); + + /* + * We should flush work before return to make sure that + * the HugeTLB page is freed to the buddy. + */ + if (!rc && h) + flush_hpage_update_work(h); + return rc; }