mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-18 10:35:55 +00:00
99 lines
3.0 KiB
Groff
99 lines
3.0 KiB
Groff
.\" Copyright (c) 2007 Joseph Koshy. All rights reserved.
|
|
.\"
|
|
.\" 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.
|
|
.\"
|
|
.\" This software is provided by Joseph Koshy ``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 Joseph Koshy 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 November 20, 2007
|
|
.Os
|
|
.Dt PMC_ENABLE 3
|
|
.Sh NAME
|
|
.Nm pmc_disable ,
|
|
.Nm pmc_enable
|
|
.Nd administrative control of hardware performance counters
|
|
.Sh LIBRARY
|
|
.Lb libpmc
|
|
.Sh SYNOPSIS
|
|
.In pmc.h
|
|
.Ft int
|
|
.Fn pmc_disable "int cpu" "int pmc"
|
|
.Ft int
|
|
.Fn pmc_enable "int cpu" "int pmc"
|
|
.Sh DESCRIPTION
|
|
These functions allow specific hardware performance monitoring
|
|
counters in a system to be disabled and enabled administratively.
|
|
The hardware performance counters available on each CPU are numbered
|
|
using small non-negative integers, in a system dependent manner.
|
|
Disabled counters will not be available to applications for use.
|
|
.Pp
|
|
The invoking process needs to have the
|
|
.Dv PRIV_PMC_MANAGE
|
|
privilege to perform these operations.
|
|
.Pp
|
|
Function
|
|
.Fn pmc_disable
|
|
disables the hardware counter numbered by argument
|
|
.Fa pmc
|
|
on CPU number
|
|
.Fa cpu .
|
|
.Pp
|
|
Function
|
|
.Fn pmc_enable
|
|
enables the hardware counter numbered by argument
|
|
.Fa pmc
|
|
on CPU number
|
|
.Fa cpu .
|
|
.Sh IMPLEMENTATION NOTES
|
|
Hardware PMCs that are currently in use by applications cannot be
|
|
disabled.
|
|
Allocation of a process scope software PMC marks all
|
|
hardware PMCs in the system with the same pmc number as being in-use.
|
|
.Sh RETURN VALUES
|
|
.Rv -std
|
|
.Sh ERRORS
|
|
A call to these functions may fail with the following errors:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EBUSY
|
|
Function
|
|
.Fn pmc_disable
|
|
specified a hardware PMC is currently in use.
|
|
.It Bq Er EINVAL
|
|
Arguments
|
|
.Fa cpu
|
|
or
|
|
.Fa pmc
|
|
were invalid.
|
|
.It Bq Er ENXIO
|
|
Argument
|
|
.Fa cpu
|
|
specified a disabled CPU.
|
|
.It Bq Er EPERM
|
|
The current process lacks sufficient privilege to perform this
|
|
operation.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr pmc 3 ,
|
|
.Xr pmc_cpuinfo 3 ,
|
|
.Xr pmc_pmcinfo 3 ,
|
|
.Xr hwpmc 4 ,
|
|
.Xr pmccontrol 8 ,
|
|
.Xr priv_check 9 |