From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752068AbdFTMru (ORCPT ); Tue, 20 Jun 2017 08:47:50 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:8766 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751955AbdFTMrs (ORCPT ); Tue, 20 Jun 2017 08:47:48 -0400 From: Zhen Lei To: linux-kernel , linux-api , Greg Kroah-Hartman , Michal Hocko , linux-mm CC: Zefan Li , Xinwei Hu , "Tianhong Ding" , Hanjun Guo , Zhen Lei Subject: [PATCH 1/1] mm: only dispaly online cpus of the numa node Date: Tue, 20 Jun 2017 20:43:28 +0800 Message-ID: <1497962608-12756-1-git-send-email-thunder.leizhen@huawei.com> X-Mailer: git-send-email 1.9.5.msysgit.0 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.177.23.164] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020206.594918A7.013E,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 9341345198a707542b02dee59055d77c Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When I executed numactl -H(which read /sys/devices/system/node/nodeX/cpumap and display cpumask_of_node for each node), but I got different result on X86 and arm64. For each numa node, the former only displayed online CPUs, and the latter displayed all possible CPUs. Unfortunately, both Linux documentation and numactl manual have not described it clear. I sent a mail to ask for help, and Michal Hocko replied that he preferred to print online cpus because it doesn't really make much sense to bind anything on offline nodes. Signed-off-by: Zhen Lei --- drivers/base/node.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index 5548f96..d5e7ce7 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -28,12 +28,14 @@ static struct bus_type node_subsys = { static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf) { struct node *node_dev = to_node(dev); - const struct cpumask *mask = cpumask_of_node(node_dev->dev.id); + struct cpumask mask; + + cpumask_and(&mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); - return cpumap_print_to_pagebuf(list, buf, mask); + return cpumap_print_to_pagebuf(list, buf, &mask); } static inline ssize_t node_read_cpumask(struct device *dev, -- 2.5.0