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 A242FC433EF for ; Mon, 7 Mar 2022 11:51:11 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 11D6A8D0002; Mon, 7 Mar 2022 06:51:11 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 0CD938D0001; Mon, 7 Mar 2022 06:51:11 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EFDE28D0002; Mon, 7 Mar 2022 06:51:10 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.26]) by kanga.kvack.org (Postfix) with ESMTP id E33318D0001 for ; Mon, 7 Mar 2022 06:51:10 -0500 (EST) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay12.hostedemail.com (Postfix) with ESMTP id BBA16120CFF for ; Mon, 7 Mar 2022 11:51:10 +0000 (UTC) X-FDA: 79217424300.10.75F1118 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf04.hostedemail.com (Postfix) with ESMTP id C282B40005 for ; Mon, 7 Mar 2022 11:51:09 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4KBxZw6C8gzdfwr; Mon, 7 Mar 2022 19:49:44 +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 15.1.2308.21; Mon, 7 Mar 2022 19:51:05 +0800 Subject: Re: [PATCH 07/16] mm/migration: use helper macro min_t in do_pages_stat To: Andrew Morton CC: , , , , , , , , , , , , , , , , , References: <20220304093409.25829-1-linmiaohe@huawei.com> <20220304093409.25829-8-linmiaohe@huawei.com> <20220306171400.a5cbab665b6338391447e541@linux-foundation.org> From: Miaohe Lin Message-ID: Date: Mon, 7 Mar 2022 19:51:04 +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: <20220306171400.a5cbab665b6338391447e541@linux-foundation.org> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.76] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: C282B40005 X-Stat-Signature: ukrt6i9pn79537nip66uhk5bih1ixfyt X-Rspam-User: Authentication-Results: imf04.hostedemail.com; dkim=none; spf=pass (imf04.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-Rspamd-Server: rspam07 X-HE-Tag: 1646653869-191467 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 2022/3/7 9:14, Andrew Morton wrote: > On Fri, 4 Mar 2022 17:34:00 +0800 Miaohe Lin wrote: > >> We could use helper macro min_t to help set the chunk_nr to simplify >> the code. >> >> ... >> >> --- a/mm/migrate.c >> +++ b/mm/migrate.c >> @@ -1858,9 +1858,7 @@ static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages, >> while (nr_pages) { >> unsigned long chunk_nr; >> >> - chunk_nr = nr_pages; >> - if (chunk_nr > DO_PAGES_STAT_CHUNK_NR) >> - chunk_nr = DO_PAGES_STAT_CHUNK_NR; >> + chunk_nr = min_t(unsigned long, nr_pages, DO_PAGES_STAT_CHUNK_NR); >> >> if (in_compat_syscall()) { >> if (get_compat_pages_array(chunk_pages, pages, > > Getting the types correct is better than using min_t(). > Looks good. Many thanks for your suggestion. Will do it in v2. Thanks. > --- a/mm/migrate.c~mm-migration-use-helper-macro-min_t-in-do_pages_stat-fix > +++ a/mm/migrate.c > @@ -1844,14 +1844,12 @@ static int do_pages_stat(struct mm_struc > const void __user * __user *pages, > int __user *status) > { > -#define DO_PAGES_STAT_CHUNK_NR 16 > +#define DO_PAGES_STAT_CHUNK_NR 16UL > const void __user *chunk_pages[DO_PAGES_STAT_CHUNK_NR]; > int chunk_status[DO_PAGES_STAT_CHUNK_NR]; > > while (nr_pages) { > - unsigned long chunk_nr; > - > - chunk_nr = min_t(unsigned long, nr_pages, DO_PAGES_STAT_CHUNK_NR); > + unsigned long chunk_nr = min(nr_pages, DO_PAGES_STAT_CHUNK_NR); > > if (in_compat_syscall()) { > if (get_compat_pages_array(chunk_pages, pages, > _ > > . >