From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753045AbbIJT3p (ORCPT ); Thu, 10 Sep 2015 15:29:45 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:32781 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751597AbbIJT3m (ORCPT ); Thu, 10 Sep 2015 15:29:42 -0400 Date: Thu, 10 Sep 2015 15:29:35 -0400 From: Tejun Heo To: Tang Chen Cc: jiang.liu@linux.intel.com, mika.j.penttila@gmail.com, mingo@redhat.com, akpm@linux-foundation.org, rjw@rjwysocki.net, hpa@zytor.com, yasu.isimatu@gmail.com, isimatu.yasuaki@jp.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, izumi.taku@jp.fujitsu.com, gongzhaogang@inspur.com, qiaonuohan@cn.fujitsu.com, x86@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Gu Zheng Subject: Re: [PATCH v2 3/7] x86, gfp: Cache best near node for memory allocation. Message-ID: <20150910192935.GI8114@mtj.duckdns.org> References: <1441859269-25831-1-git-send-email-tangchen@cn.fujitsu.com> <1441859269-25831-4-git-send-email-tangchen@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1441859269-25831-4-git-send-email-tangchen@cn.fujitsu.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Thu, Sep 10, 2015 at 12:27:45PM +0800, Tang Chen wrote: > diff --git a/include/linux/gfp.h b/include/linux/gfp.h > index ad35f30..1a1324f 100644 > --- a/include/linux/gfp.h > +++ b/include/linux/gfp.h > @@ -307,13 +307,19 @@ static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask, > if (nid < 0) > nid = numa_node_id(); > > + if (!node_online(nid)) > + nid = get_near_online_node(nid); > + > return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask)); > } Why not just update node_data[]->node_zonelist in the first place? Also, what's the synchronization rule here? How are allocators synchronized against node hot [un]plugs? Thanks. -- tejun