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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 E232AC12002 for ; Sat, 17 Jul 2021 01:54:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2CF5461183 for ; Sat, 17 Jul 2021 01:54:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2CF5461183 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6E9508D00F4; Fri, 16 Jul 2021 21:54:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 699938D00EC; Fri, 16 Jul 2021 21:54:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5617D8D00F4; Fri, 16 Jul 2021 21:54:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0049.hostedemail.com [216.40.44.49]) by kanga.kvack.org (Postfix) with ESMTP id 3334A8D00EC for ; Fri, 16 Jul 2021 21:54:08 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id F1DD727702 for ; Sat, 17 Jul 2021 01:54:06 +0000 (UTC) X-FDA: 78370409292.01.EEA73A0 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf08.hostedemail.com (Postfix) with ESMTP id 0EDC630000A0 for ; Sat, 17 Jul 2021 01:54:05 +0000 (UTC) Received: from dggeme703-chm.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4GRWJx1QS4z7t7m; Sat, 17 Jul 2021 09:50:25 +0800 (CST) Received: from [10.174.178.125] (10.174.178.125) by dggeme703-chm.china.huawei.com (10.1.199.99) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Sat, 17 Jul 2021 09:54:00 +0800 Subject: Re: [PATCH 2/3] mm/vmstat: simplify the array size calculation To: David Hildenbrand CC: , , Andrew Morton References: <20210715122911.15700-1-linmiaohe@huawei.com> <20210715122911.15700-3-linmiaohe@huawei.com> <79fb76da-f811-7030-abd6-1dd970e7ab53@redhat.com> From: Miaohe Lin Message-ID: Date: Sat, 17 Jul 2021 09:54:00 +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: <79fb76da-f811-7030-abd6-1dd970e7ab53@redhat.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US X-Originating-IP: [10.174.178.125] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggeme703-chm.china.huawei.com (10.1.199.99) X-CFilter-Loop: Reflected Authentication-Results: imf08.hostedemail.com; dkim=none; spf=pass (imf08.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com; dmarc=pass (policy=none) header.from=huawei.com X-Stat-Signature: 4p3atifwzydf9yipeiyi7eyyrf9e4b3a X-Rspamd-Queue-Id: 0EDC630000A0 X-Rspamd-Server: rspam01 X-HE-Tag: 1626486845-185235 Content-Transfer-Encoding: quoted-printable 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 2021/7/16 20:58, David Hildenbrand wrote: > On 15.07.21 14:29, Miaohe Lin wrote: >> We can replace the array_num * sizeof(array[0]) with sizeof(array) to >> simplify the code. >=20 > Could have mentioned taht your fixing indentation of one "return true;" >=20 Yes, but I thought that's too trivial to mention... I would pay attention= to it later. > LGTM >=20 > Reviewed-by: David Hildenbrand Many thanks for your review and reply! >=20 >> >> Signed-off-by: Miaohe Lin >> --- >> =C2=A0 mm/vmstat.c | 8 +++----- >> =C2=A0 1 file changed, 3 insertions(+), 5 deletions(-) >> >> diff --git a/mm/vmstat.c b/mm/vmstat.c >> index 57e8e7fda7aa..76aef9510f6d 100644 >> --- a/mm/vmstat.c >> +++ b/mm/vmstat.c >> @@ -1889,17 +1889,15 @@ static bool need_update(int cpu) >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /* >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 * The fas= t way of checking if there are any vmstat diffs. >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 */ >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (memchr_inv(pzstats->vm= _stat_diff, 0, NR_VM_ZONE_STAT_ITEMS * >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 sizeof(pzstats->vm_stat_diff[0]))= ) >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (memchr_inv(pzstats->vm= _stat_diff, 0, sizeof(pzstats->vm_stat_diff))) >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0 return true; >> =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (last= _pgdat =3D=3D zone->zone_pgdat) >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0 continue; >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 last_pgdat =3D = zone->zone_pgdat; >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 n =3D per_cpu_p= tr(zone->zone_pgdat->per_cpu_nodestats, cpu); >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (memchr_inv(n->vm_node_= stat_diff, 0, NR_VM_NODE_STAT_ITEMS * >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 sizeof(n->vm_node_stat_diff[0]))) >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 re= turn true; >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (memchr_inv(n->vm_node_= stat_diff, 0, sizeof(n->vm_node_stat_diff))) >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 re= turn true; >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 } >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 return false; >> =C2=A0 } >> >=20 >=20