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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB55EC43334 for ; Fri, 24 Jun 2022 09:51:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3F0DA8E020B; Fri, 24 Jun 2022 05:51:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 39FB88E0205; Fri, 24 Jun 2022 05:51:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2683B8E020B; Fri, 24 Jun 2022 05:51:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 1422D8E0205 for ; Fri, 24 Jun 2022 05:51:26 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id DD6EF20C7A for ; Fri, 24 Jun 2022 09:51:25 +0000 (UTC) X-FDA: 79612661730.09.4D6535B Received: from out30-54.freemail.mail.aliyun.com (out30-54.freemail.mail.aliyun.com [115.124.30.54]) by imf08.hostedemail.com (Postfix) with ESMTP id B2BE5160026 for ; Fri, 24 Jun 2022 09:51:23 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046059;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VHGqj-b_1656064279; Received: from 30.97.49.29(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0VHGqj-b_1656064279) by smtp.aliyun-inc.com; Fri, 24 Jun 2022 17:51:19 +0800 Message-ID: Date: Fri, 24 Jun 2022 17:51:25 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [PATCH 5/7] migrate_pages(): fix failure counting for THP on -ENOSYS To: Huang Ying , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Zi Yan , Yang Shi References: <20220624025309.1033400-1-ying.huang@intel.com> <20220624025309.1033400-6-ying.huang@intel.com> From: Baolin Wang In-Reply-To: <20220624025309.1033400-6-ying.huang@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656064284; a=rsa-sha256; cv=none; b=zLOOs4wJfyUQwrWb16XFTzNitwVPjy2cqraK1m/gvdBj+dUQOCSOj3NO38D/qXHcgwgOdO dLkaE1hyanOMVq7dhzrkqVxYnCl8AWW8mywZYuIXXDamTyHO/NGfKj1LFrhfETiMSTAaMJ KzkFALMIBVwDLG0ovjQlQcvduV/52OU= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf08.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 115.124.30.54 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656064284; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=B9hPiLZHbgHP1PDzmw8s3LnN56nTgd9c6A8eG1jjQVE=; b=WU2SZ5BBXmNILkma8zApjZfszSxG2jZM8mhwvgxERl3kYNmVtdod7ca0nTYNPv2BsWgS8q vdIw3W1dTf+CUFUbPDRwocMxtSPdRyPKY12C6CIRwFvJjV+YaF4PRlw4LKam/vUM/BOABN 5Np51gxZtLFktT8eKeGwiPWi46WOjHo= X-Stat-Signature: nigxte4myzqsubxy7ttgdqr89abbunss X-Rspamd-Queue-Id: B2BE5160026 Authentication-Results: imf08.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf08.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 115.124.30.54 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com X-Rspamd-Server: rspam10 X-Rspam-User: X-HE-Tag: 1656064283-643334 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 6/24/2022 10:53 AM, Huang Ying wrote: > If THP or hugetlbfs page migration isn't supported, unmap_and_move() > or unmap_and_move_huge_page() will return -ENOSYS. For THP, splitting > will be tried, but if splitting doesn't succeed, the THP will be left > in "from" list wrongly. If some other pages are retried, the THP > migration failure will counted again. This is fixed via moving the > failure THP from "from" to "ret_pages". > > Another issue of the original code is that the unsupported failure > processing isn't consistent between THP and hugetlbfs page. Make them > consistent in this patch to make the code easier to be understood too. > > Signed-off-by: "Huang, Ying" > Fixes: 5984fabb6e82 ("mm: move_pages: report the number of non-attempted pages") > Cc: Baolin Wang > Cc: Zi Yan > Cc: Yang Shi > --- LGTM. Reviewed-by: Baolin Wang > mm/migrate.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index 61dab3025a1d..9d1883d5927f 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -1191,10 +1191,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, > * tables or check whether the hugepage is pmd-based or not before > * kicking migration. > */ > - if (!hugepage_migration_supported(page_hstate(hpage))) { > - list_move_tail(&hpage->lru, ret); > + if (!hugepage_migration_supported(page_hstate(hpage))) > return -ENOSYS; > - } > > if (page_count(hpage) == 1) { > /* page was freed from under us. So we are done. */ > @@ -1391,6 +1389,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, > * page will be put back > * -EAGAIN: stay on the from list > * -ENOMEM: stay on the from list > + * -ENOSYS: stay on the from list > * Other errno: put on ret_pages list then splice to > * from list > */ > @@ -1420,6 +1419,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, > } > > nr_failed_pages += nr_subpages; > + list_move_tail(&page->lru, &ret_pages); > break; > case -ENOMEM: > /*