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 4471BC433EF for ; Wed, 13 Apr 2022 04:42:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 75B766B0072; Wed, 13 Apr 2022 00:42:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6E3166B0073; Wed, 13 Apr 2022 00:42:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5836F6B0074; Wed, 13 Apr 2022 00:42:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.27]) by kanga.kvack.org (Postfix) with ESMTP id 41FB16B0072 for ; Wed, 13 Apr 2022 00:42:42 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 0A79B24E5F for ; Wed, 13 Apr 2022 04:42:42 +0000 (UTC) X-FDA: 79350610164.13.DF1733A Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf07.hostedemail.com (Postfix) with ESMTP id 4C99B40009 for ; Wed, 13 Apr 2022 04:42:41 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7628F61B89; Wed, 13 Apr 2022 04:42:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 716F5C385A4; Wed, 13 Apr 2022 04:42:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1649824959; bh=BO4/OgfkvQXwuWlu6YluOvcDnCx28FhpevAMGxUUcZE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=shlE7lCEhNaqsAU6Qrd654pmXjf3ofBQxnj+KuFvMeeGwYBZkxovxz2Zi/98xyPZz q2CUs71OykxdbRQBCBnvYiJY/POcd2e2OAsoIEF2Y03SjsS3Wabedt6oPz6pnDFvIE UYMSM67lIk82yfgw6hlXsf5pFS7ho4M3qyrwgq0g= Date: Tue, 12 Apr 2022 21:42:38 -0700 From: Andrew Morton To: Peng Liu Cc: , , , , , , , Subject: Re: [PATCH v3 1/4] hugetlb: Fix wrong use of nr_online_nodes Message-Id: <20220412214238.84c20437a052458f6967e9fd@linux-foundation.org> In-Reply-To: <20220413032915.251254-2-liupeng256@huawei.com> References: <20220413032915.251254-1-liupeng256@huawei.com> <20220413032915.251254-2-liupeng256@huawei.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 4C99B40009 X-Rspam-User: Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=shlE7lCE; dmarc=none; spf=pass (imf07.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Stat-Signature: dkmoogh16x5niqkeihpd3ikb1ipdbnht X-HE-Tag: 1649824961-747395 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 Wed, 13 Apr 2022 03:29:12 +0000 Peng Liu wrote: > Certain systems are designed to have sparse/discontiguous nodes. In > this case, nr_online_nodes can not be used to walk through numa node. > Also, a valid node may be greater than nr_online_nodes. > > However, in hugetlb, it is assumed that nodes are contiguous. Recheck > all the places that use nr_online_nodes, and repair them one by one. > What are the runtime effects of this shortcoming?