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=-9.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 47AD4C433E6 for ; Mon, 20 Jul 2020 08:27:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2ADAB22B4D for ; Mon, 20 Jul 2020 08:27:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727993AbgGTI1N (ORCPT ); Mon, 20 Jul 2020 04:27:13 -0400 Received: from mx2.suse.de ([195.135.220.15]:58642 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725845AbgGTI1M (ORCPT ); Mon, 20 Jul 2020 04:27:12 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id BE7EBADF2; Mon, 20 Jul 2020 08:27:16 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 20 Jul 2020 10:27:10 +0200 From: osalvador@suse.de To: =?UTF-8?Q?HORIGUCHI_NAOYA=28=E5=A0=80=E5=8F=A3=E3=80=80=E7=9B=B4?= =?UTF-8?Q?=E4=B9=9F=29?= Cc: akpm@linux-foundation.org, Michal Hocko , linux-mm@kvack.org, mike.kravetz@oracle.com, david@redhat.com, aneesh.kumar@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, Oscar Salvador Subject: Re: [PATCH v4 12/15] mm,hwpoison: Rework soft offline for in-use pages In-Reply-To: References: <20200716123810.25292-1-osalvador@suse.de> <20200716123810.25292-13-osalvador@suse.de> User-Agent: Roundcube Webmail Message-ID: X-Sender: osalvador@suse.de Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-07-17 08:55, HORIGUCHI NAOYA wrote: > I ran Quan Cai's test program (https://github.com/cailca/linux-mm) on a > small (4GB memory) VM, and weiredly found that (1) the target hugepages > are not always dissolved and (2) dissovled hugetpages are still counted > in "HugePages_Total:". See below: > > $ ./random 1 > - start: migrate_huge_offline > - use NUMA nodes 0,1. > - mmap and free 8388608 bytes hugepages on node 0 > - mmap and free 8388608 bytes hugepages on node 1 > madvise: Cannot allocate memory > > $ cat /proc/meminfo > MemTotal: 4026772 kB > MemFree: 976300 kB > MemAvailable: 892840 kB > Buffers: 20936 kB > Cached: 99768 kB > SwapCached: 5904 kB > Active: 84332 kB > Inactive: 116328 kB > Active(anon): 27944 kB > Inactive(anon): 68524 kB > Active(file): 56388 kB > Inactive(file): 47804 kB > Unevictable: 7532 kB > Mlocked: 0 kB > SwapTotal: 2621436 kB > SwapFree: 2609844 kB > Dirty: 56 kB > Writeback: 0 kB > AnonPages: 81764 kB > Mapped: 54348 kB > Shmem: 8948 kB > KReclaimable: 22744 kB > Slab: 52056 kB > SReclaimable: 22744 kB > SUnreclaim: 29312 kB > KernelStack: 3888 kB > PageTables: 2804 kB > NFS_Unstable: 0 kB > Bounce: 0 kB > WritebackTmp: 0 kB > CommitLimit: 3260612 kB > Committed_AS: 828196 kB > VmallocTotal: 34359738367 kB > VmallocUsed: 19260 kB > VmallocChunk: 0 kB > Percpu: 5120 kB > HardwareCorrupted: 5368 kB > AnonHugePages: 18432 kB > ShmemHugePages: 0 kB > ShmemPmdMapped: 0 kB > FileHugePages: 0 kB > FilePmdMapped: 0 kB > CmaTotal: 0 kB > CmaFree: 0 kB > HugePages_Total: 1342 // still counted as hugetlb pages. > HugePages_Free: 0 // all hugepage are still allocated > (or leaked?) > HugePages_Rsvd: 0 > HugePages_Surp: 762 // some are counted in surplus. > Hugepagesize: 2048 kB > Hugetlb: 2748416 kB > DirectMap4k: 112480 kB > DirectMap2M: 4081664 kB > > > $ page-types -b hwpoison > flags page-count MB symbolic-flags > long-symbolic-flags > 0x0000000000080008 421 1 > ___U_______________X_______________________ uptodate,hwpoison > 0x00000000000a8018 1 0 > ___UD__________H_G_X_______________________ > uptodate,dirty,compound_head,huge,hwpoison > 0x00000000000a801c 920 3 > __RUD__________H_G_X_______________________ > referenced,uptodate,dirty,compound_head,huge,hwpoison > total 1342 5 > > This means that some hugepages are dissolved, but the others not, > maybe which is not desirable. > I'll dig this more later but just let me share at first. > > A few minor comment below ... Uhm, weird. I will be taking a look today. Thanks