1.\" $NetBSD: cpuctl.8,v 1.6 2008/06/22 14:50:40 wiz Exp $ 2.\" 3.\" Copyright (c) 2007, 2008 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Andrew Doran. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd June 22, 2008 31.Dt CPUCTL 8 32.Os 33.Sh NAME 34.Nm cpuctl 35.Nd program to control CPUs 36.Sh SYNOPSIS 37.Nm cpuctl 38.Ar command 39.Op Ar arguments 40.Sh DESCRIPTION 41The 42.Nm 43command can be used to control and inspect the state of CPUs in the system. 44.Pp 45The first argument, 46.Ar command , 47specifies the action to take. 48Valid commands are: 49.Bl -tag -width XofflineXcpunoX 50.It identify Ar cpu 51Output information on the specified CPU's features and capabilities. 52Not available on all architectures. 53.It list 54For each CPU in the system, display the current state and time of the last 55state change. 56.It offline Ar cpuno 57Set the specified CPU off line. 58.Pp 59Unbound LWPs (lightweight processes) will not be executed on the CPU 60while it is off line. 61Bound LWPs will continue to be executed on the CPU, and device interrupts 62routed to the CPU will continue to be handled. 63A future release of the system may allow device interrupts to be re-routed 64away from individual CPUs. 65.Pp 66At least one CPU in the system must remain on line. 67.It online Ar cpuno 68Set the specified CPU on line, making it available to run unbound LWPs. 69.El 70.Sh FILES 71.Bl -tag -width /dev/cpuctl -compact 72.It Pa /dev/cpuctl 73control device 74.El 75.Sh SEE ALSO 76.Xr psrset 8 , 77.Xr schedctl 8 78.Sh HISTORY 79The 80.Nm 81command first appeared in 82.Nx 5.0 . 83