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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 6AD80C433DF for ; Fri, 16 Oct 2020 03:05:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3580F2087D for ; Fri, 16 Oct 2020 03:05:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602817540; bh=hZJ7IDPfE2iiF4yamOZcSBr7NJL3j1MrnxSHubN5nxc=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=YhiidnM2tnZblwPsVuXRDkT42BrHSJOJcXTo8C9P1aYJVRtCY2m8TZ6MZckQsIlef SrjKrHn7clDy6KmaoEROGN3gyOwmAFUqaM4INWec+/eQ1CNlnYRDUymzCRrlJNaBaF LWWrSaJAvmoRKIbh3olpwshxDRwH3RRvvrJu5w0E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393940AbgJPDFj (ORCPT ); Thu, 15 Oct 2020 23:05:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:44210 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728261AbgJPDFj (ORCPT ); Thu, 15 Oct 2020 23:05:39 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 14DE820789; Fri, 16 Oct 2020 03:05:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602817537; bh=hZJ7IDPfE2iiF4yamOZcSBr7NJL3j1MrnxSHubN5nxc=; h=Date:From:To:Subject:In-Reply-To:From; b=He3Koc+0/ArysxUk5kcYCXrSxkYV9gVcbywfDZshEJXOl89+IRrcWtsn+VQY66LpG moJ3gxceqCZut8tFxFCU8ML2ublfZlEfWtj5OT3gxgGImtqCt0RO9Xw5//V76YR9qI I7IKkN+i/3wMdhU5xgXWkrn3TiaZubSWkbdCBu48= Date: Thu, 15 Oct 2020 20:05:36 -0700 From: Andrew Morton To: akpm@linux-foundation.org, kirill@shutemov.name, mm-commits@vger.kernel.org, sjpark@amazon.de, torvalds@linux-foundation.org, willy@infradead.org, ying.huang@intel.com Subject: [patch 023/156] mm/huge_memory: fix split assumption of page size Message-ID: <20201016030536.7W9s4Vm6Y%akpm@linux-foundation.org> In-Reply-To: <20201015194043.84cda0c1d6ca2a6847f2384a@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: "Kirill A. Shutemov" Subject: mm/huge_memory: fix split assumption of page size File THPs may now be of arbitrary size, and we can't rely on that size after doing the split so remember the number of pages before we start the split. Link: https://lkml.kernel.org/r/20200908195539.25896-6-willy@infradead.org Signed-off-by: Kirill A. Shutemov Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: SeongJae Park Cc: Huang Ying Signed-off-by: Andrew Morton --- mm/huge_memory.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-fix-split-assumption-of-page-size +++ a/mm/huge_memory.c @@ -2335,13 +2335,13 @@ static void unmap_page(struct page *page VM_BUG_ON_PAGE(!unmap_success, page); } -static void remap_page(struct page *page) +static void remap_page(struct page *page, unsigned int nr) { int i; if (PageTransHuge(page)) { remove_migration_ptes(page, page, true); } else { - for (i = 0; i < HPAGE_PMD_NR; i++) + for (i = 0; i < nr; i++) remove_migration_ptes(page + i, page + i, true); } } @@ -2419,6 +2419,7 @@ static void __split_huge_page(struct pag struct lruvec *lruvec; struct address_space *swap_cache = NULL; unsigned long offset = 0; + unsigned int nr = thp_nr_pages(head); int i; lruvec = mem_cgroup_page_lruvec(head, pgdat); @@ -2434,7 +2435,7 @@ static void __split_huge_page(struct pag xa_lock(&swap_cache->i_pages); } - for (i = HPAGE_PMD_NR - 1; i >= 1; i--) { + for (i = nr - 1; i >= 1; i--) { __split_huge_page_tail(head, i, lruvec, list); /* Some pages can be beyond i_size: drop them from page cache */ if (head[i].index >= end) { @@ -2454,7 +2455,7 @@ static void __split_huge_page(struct pag ClearPageCompound(head); - split_page_owner(head, HPAGE_PMD_NR); + split_page_owner(head, nr); /* See comment in __split_huge_page_tail() */ if (PageAnon(head)) { @@ -2473,9 +2474,9 @@ static void __split_huge_page(struct pag spin_unlock_irqrestore(&pgdat->lru_lock, flags); - remap_page(head); + remap_page(head, nr); - for (i = 0; i < HPAGE_PMD_NR; i++) { + for (i = 0; i < nr; i++) { struct page *subpage = head + i; if (subpage == page) continue; @@ -2729,7 +2730,7 @@ int split_huge_page_to_list(struct page fail: if (mapping) xa_unlock(&mapping->i_pages); spin_unlock_irqrestore(&pgdata->lru_lock, flags); - remap_page(head); + remap_page(head, thp_nr_pages(head)); ret = -EBUSY; } _