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 210F3C433F5 for ; Mon, 9 May 2022 07:51:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 937656B0071; Mon, 9 May 2022 03:51:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8E8BE6B0073; Mon, 9 May 2022 03:51:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7D6756B0074; Mon, 9 May 2022 03:51:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 6B6C86B0071 for ; Mon, 9 May 2022 03:51:45 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 42DAE30305 for ; Mon, 9 May 2022 07:51:45 +0000 (UTC) X-FDA: 79445435370.13.85EC53E Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by imf06.hostedemail.com (Postfix) with ESMTP id 0E1A218007E for ; Mon, 9 May 2022 07:51:41 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.56]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4KxYCf71WDzCsP6; Mon, 9 May 2022 15:46:54 +0800 (CST) Received: from [10.174.177.76] (10.174.177.76) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 9 May 2022 15:51:39 +0800 Subject: Re: [PATCH v2 3/4] mm/migration: return errno when isolate_huge_page failed To: Muchun Song CC: Andrew Morton , Mike Kravetz , =?UTF-8?B?SE9SSUdVQ0hJIE5BT1lBKOWggOWPoyDnm7TkuZ8p?= , Huang Ying , Christoph Hellwig , , Christoph Lameter , David Hildenbrand , Linux Memory Management List , LKML References: <20220425132723.34824-1-linmiaohe@huawei.com> <20220425132723.34824-4-linmiaohe@huawei.com> <09ccdbac-c267-15de-0d81-57e211dea6d2@huawei.com> From: Miaohe Lin Message-ID: Date: Mon, 9 May 2022 15:51:39 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.76] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: 0E1A218007E X-Stat-Signature: fozo1anmotn45jh17ruhhj7qdq7phtxn Authentication-Results: imf06.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf06.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.189 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1652082701-734034 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 2022/5/9 12:21, Muchun Song wrote: > On Mon, May 9, 2022 at 11:24 AM Miaohe Lin wrote: >> >> On 2022/4/29 19:36, Muchun Song wrote: >>> On Mon, Apr 25, 2022 at 09:27:22PM +0800, Miaohe Lin wrote: >>>> We might fail to isolate huge page due to e.g. the page is under migration >>>> which cleared HPageMigratable. So we should return -EBUSY in this case >>>> rather than always return 1 which could confuse the user. Also we make >>>> the prototype of isolate_huge_page consistent with isolate_lru_page to >>>> improve the readability. >>>> >>>> Fixes: e8db67eb0ded ("mm: migrate: move_pages() supports thp migration") >>>> Suggested-by: Huang Ying >>>> Signed-off-by: Miaohe Lin >>>> --- >>>> include/linux/hugetlb.h | 6 +++--- >>>> mm/gup.c | 2 +- >>>> mm/hugetlb.c | 11 +++++------ >>>> mm/memory-failure.c | 2 +- >>>> mm/mempolicy.c | 2 +- >>>> mm/migrate.c | 5 +++-- >>>> 6 files changed, 14 insertions(+), 14 deletions(-) >>>> >>>> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h >>>> index 04f0186b089b..306d6ef3fa22 100644 >>>> --- a/include/linux/hugetlb.h >>>> +++ b/include/linux/hugetlb.h >>>> @@ -170,7 +170,7 @@ bool hugetlb_reserve_pages(struct inode *inode, long from, long to, >>>> vm_flags_t vm_flags); >>>> long hugetlb_unreserve_pages(struct inode *inode, long start, long end, >>>> long freed); >>>> -bool isolate_huge_page(struct page *page, struct list_head *list); >>>> +int isolate_huge_page(struct page *page, struct list_head *list); >>>> int get_hwpoison_huge_page(struct page *page, bool *hugetlb); >>>> int get_huge_page_for_hwpoison(unsigned long pfn, int flags); >>>> void putback_active_hugepage(struct page *page); >>>> @@ -376,9 +376,9 @@ static inline pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, >>>> return NULL; >>>> } >>>> >>>> -static inline bool isolate_huge_page(struct page *page, struct list_head *list) >>>> +static inline int isolate_huge_page(struct page *page, struct list_head *list) >>> >>> Since you already touched all the call sites, how about renaming this >>> to hugetlb_isolate()? I've always felt that huge_page is not a >>> straightforward and clear name since we also have another type of >>> huge page (THP). I think hugetlb is more specific. >>> >> >> Sorry for late respond. This suggestion looks good to me. But is isolate_hugetlb more suitable? >> This could make it more consistent with isolate_lru_page? What do you think? >> > > There is also a function named folio_isolate_lru(). My initial consideration was > making it consistent with folio_isolate_lru(). isolate_hugetlb looks good to me > as well. I see. Many thanks for your explanation. :) > > Thanks. > . >