From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754418AbZKPVRP (ORCPT ); Mon, 16 Nov 2009 16:17:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754178AbZKPVRO (ORCPT ); Mon, 16 Nov 2009 16:17:14 -0500 Received: from g1t0029.austin.hp.com ([15.216.28.36]:10353 "EHLO g1t0029.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754064AbZKPVRO (ORCPT ); Mon, 16 Nov 2009 16:17:14 -0500 Date: Mon, 16 Nov 2009 14:17:19 -0700 From: Alex Chiang To: gregkh@suse.de Cc: linux-kernel Subject: [PATCH] Documentation: ABI: /sys/devices/system/cpu/cpu#/online Message-ID: <20091116211719.GE21242@ldl.fc.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add documentation for CPU hotplug interface. Signed-off-by: Alex Chiang --- I forgot to send this patch in the last round of documentation updates, and wanted to send it before it gets misplaced. ;) --- diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index a703b9e..5aace16 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -62,7 +62,6 @@ Description: CPU topology files that describe kernel limits related to See Documentation/cputopology.txt for more information. - What: /sys/devices/system/cpu/cpu#/node Date: October 2009 Contact: Linux memory management mailing list @@ -77,6 +76,24 @@ Description: Discover NUMA node a CPU belongs to /sys/devices/system/cpu/cpu42/node2 -> ../../node/node2 +What: /sys/devices/system/cpu/cpu#/online +Date: January 2006 +Contact: Linux kernel mailing list +Description: Discover and change the online state of a CPU. + + To discover the state: + + cat /sys/devices/system/cpu/cpu#/online + + A value of 0 indicates the CPU is offline. A value of 1 + indicates it is online. To change the state, echo the + desired new state into the file: + + echo [0|1] > /sys/devices/system/cpu/$cpu/online + + For more information, please read Documentation/cpu-hotplug.txt + + What: /sys/devices/system/cpu/cpu#/topology/core_id /sys/devices/system/cpu/cpu#/topology/core_siblings /sys/devices/system/cpu/cpu#/topology/core_siblings_list