From 67b02c52de29cfb44eea11a7c46f7bf5de57bf36 Mon Sep 17 00:00:00 2001 From: jhb Date: Tue, 19 Aug 2008 21:30:36 +0000 Subject: Add a new routine kvm_getcptime(3) for fetching the equivalent of 'kern.cp_time'. For a live kernel it uses the sysctl. For a crashdump, it first checks to see if the kernel has a 'cp_time' global symbol. If it does, it uses that. If that doesn't work, when it uses the recently added kvm_getmaxcpu(3) and kvm_getpcpu(3) routines to walk all the CPUs and sum up their counters. MFC after: 1 week --- lib/libkvm/kvm_getcptime.3 | 77 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 lib/libkvm/kvm_getcptime.3 (limited to 'lib/libkvm/kvm_getcptime.3') diff --git a/lib/libkvm/kvm_getcptime.3 b/lib/libkvm/kvm_getcptime.3 new file mode 100644 index 0000000..2ddc272 --- /dev/null +++ b/lib/libkvm/kvm_getcptime.3 @@ -0,0 +1,77 @@ +.\" Copyright (c) 2008 Yahoo!, Inc. +.\" All rights reserved. +.\" Written by: John Baldwin +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the author nor the names of any co-contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd August 19, 2008 +.Dt KVM_GETCPTIME 3 +.Os +.Sh NAME +.Nm kvm_getcptime +.Nd fetch global CPU time statistics +.Sh LIBRARY +.Lb libkvm +.Sh SYNOPSIS +.In sys/param.h +.In sys/resource.h +.In sys/sysctl.h +.In kvm.h +.Ft int +.Fn kvm_getcptime "kvm_t *kd" "long *cp_time" +.Sh DESCRIPTION +The +.Fn kvm_getcptime +function stores the global CPU time statistics from the kernel +.Fa kd +in the array of counters pointed to by +.Fa cp_time . +Note that +.Fa cp_time +should point to an array of +.Dv CPUSTATES +long integers. +The format of the counters is identical to that output by the +.Va kern.cp_time +sysctl. +.Sh CACHING +This function caches the nlist values for various kernel variables which it +reuses in successive calls. +You may call the function with +.Fa kd +set to +.Dv NULL +to clear this cache. +.Sh RETURN VALUES +The +.Nm kvm_getcptime +function returns 0 on success and -1 on failure. +If an error occurs, +then an error message may be retrieved via +.Xr kvm_geterr 3 . +.Sh SEE ALSO +.Xr kvm 3 -- cgit v1.1