From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757962AbZJSVee (ORCPT ); Mon, 19 Oct 2009 17:34:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757945AbZJSVec (ORCPT ); Mon, 19 Oct 2009 17:34:32 -0400 Received: from g1t0026.austin.hp.com ([15.216.28.33]:1780 "EHLO g1t0026.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757838AbZJSVeb (ORCPT ); Mon, 19 Oct 2009 17:34:31 -0400 Subject: [PATCH 5/5] Documentation: ABI: document /sys/devices/system/cpu/ To: akpm@linux-foundation.org From: Alex Chiang Cc: Randy Dunlap , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Greg KH Date: Mon, 19 Oct 2009 15:34:35 -0600 Message-ID: <20091019213435.32729.81751.stgit@bob.kio> In-Reply-To: <20091019212740.32729.7171.stgit@bob.kio> References: <20091019212740.32729.7171.stgit@bob.kio> User-Agent: StGit/0.14.3.386.gb02d MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This interface has been around for a long time, but hasn't been officially documented. Since I wanted to extend the ABI, I figured I would document what already existed. Cc: Greg KH Cc: Randy Dunlap Signed-off-by: Alex Chiang --- Documentation/ABI/testing/sysfs-devices-cpu | 42 +++++++++++++++++++++++++++ 1 files changed, 42 insertions(+), 0 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-devices-cpu diff --git a/Documentation/ABI/testing/sysfs-devices-cpu b/Documentation/ABI/testing/sysfs-devices-cpu new file mode 100644 index 0000000..9070889 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-cpu @@ -0,0 +1,42 @@ +What: /sys/devices/system/cpu/ +Date: October 2009 +Contact: Linux kernel mailing list +Description: + A collection of CPU attributes, including cache information, + topology, and frequency. It also contains a mechanism to + logically hotplug CPUs. + + The actual attributes present are architecture and + configuration dependent. + + +What: /sys/devices/system/cpu/$cpu/online +Date: January 2006 +Contact: Linux kernel mailing list +Description: + When CONFIG_HOTPLUG_CPU is enabled, allows the user to + discover and change the online state of a CPU. To discover + the state: + + cat /sys/devices/system/cpu/$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/node +Date: October 2009 +Contact: Linux memory management mailing list +Description: + When CONFIG_NUMA is enabled, a symbolic link that points + to the corresponding NUMA node directory. + + For example, the following symlink is created for cpu42 + in NUMA node 2: + + /sys/devices/system/cpu/cpu42/node2 -> ../../node/node2