From patchwork Mon Feb 7 13:36:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12737251 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 0944DC433EF for ; Mon, 7 Feb 2022 13:37:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 71E726B0075; Mon, 7 Feb 2022 08:37:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 69DE16B007E; Mon, 7 Feb 2022 08:37:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3696A6B0078; Mon, 7 Feb 2022 08:37:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0224.hostedemail.com [216.40.44.224]) by kanga.kvack.org (Postfix) with ESMTP id 202B86B0075 for ; Mon, 7 Feb 2022 08:37:27 -0500 (EST) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 9F277181ECAD2 for ; Mon, 7 Feb 2022 13:37:26 +0000 (UTC) X-FDA: 79116085692.10.58F2D97 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf19.hostedemail.com (Postfix) with ESMTP id E6A521A000E for ; Mon, 7 Feb 2022 13:37:25 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4JsnCD2jbDzZfPd; Mon, 7 Feb 2022 21:33:12 +0800 (CST) Received: from huawei.com (10.175.124.27) 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 Feb 2022 21:37:22 +0800 From: Miaohe Lin To: CC: , , Subject: [PATCH 2/4] mm/memory_hotplug: avoid calling zone_intersects() for ZONE_NORMAL Date: Mon, 7 Feb 2022 21:36:41 +0800 Message-ID: <20220207133643.23427-3-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220207133643.23427-1-linmiaohe@huawei.com> References: <20220207133643.23427-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: E6A521A000E X-Stat-Signature: psa8i8jia8fgmyntu3yuzbp45aj1tp3n Authentication-Results: imf19.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf19.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-Rspam-User: nil X-HE-Tag: 1644241045-273464 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: If zid reaches ZONE_NORMAL, the caller will always get the NORMAL zone no matter what zone_intersects() returns. So we can save some possible cpu cycles by avoid calling zone_intersects() for ZONE_NORMAL. Signed-off-by: Miaohe Lin Reviewed-by: David Hildenbrand Reviewed-by: Oscar Salvador --- mm/memory_hotplug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index cbc67c27e0dd..140809e60e9a 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -826,7 +826,7 @@ static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn struct pglist_data *pgdat = NODE_DATA(nid); int zid; - for (zid = 0; zid <= ZONE_NORMAL; zid++) { + for (zid = 0; zid < ZONE_NORMAL; zid++) { struct zone *zone = &pgdat->node_zones[zid]; if (zone_intersects(zone, start_pfn, nr_pages))