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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2AFC3C433FE for ; Mon, 7 Feb 2022 13:52:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1389219AbiBGNvX (ORCPT ); Mon, 7 Feb 2022 08:51:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1387669AbiBGNiC (ORCPT ); Mon, 7 Feb 2022 08:38:02 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C562C0401D4 for ; Mon, 7 Feb 2022 05:37:24 -0800 (PST) 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 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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)) -- 2.23.0