From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id E11886B0033 for ; Mon, 6 Feb 2017 18:29:34 -0500 (EST) Received: by mail-pf0-f199.google.com with SMTP id d123so124175125pfd.0 for ; Mon, 06 Feb 2017 15:29:34 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id 1si2120548plw.105.2017.02.06.15.29.33 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 06 Feb 2017 15:29:34 -0800 (PST) Date: Mon, 6 Feb 2017 15:29:32 -0800 From: Andrew Morton Subject: Re: [PATCH] mm/page_alloc: return 0 in case this node has no page within the zone Message-Id: <20170206152932.19e7947df487b96b8912e524@linux-foundation.org> In-Reply-To: <20170206154314.15705-1-richard.weiyang@gmail.com> References: <20170206154314.15705-1-richard.weiyang@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Wei Yang Cc: vbabka@suse.cz, mgorman@techsingularity.net, mhocko@suse.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Mon, 6 Feb 2017 23:43:14 +0800 Wei Yang wrote: > The whole memory space is divided into several zones and nodes may have no > page in some zones. In this case, the __absent_pages_in_range() would > return 0, since the range it is searching for is an empty range. > > Also this happens more often to those nodes with higher memory range when > there are more nodes, which is a trend for future architectures. > > This patch checks the zone range after clamp and adjustment, return 0 if > the range is an empty range. What are the user-visible runtime effects of this change? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org