mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-11 09:50:12 +00:00
85 lines
2.6 KiB
Groff
85 lines
2.6 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 25, 2007
|
|
.Os
|
|
.Dt PMC_READ 3
|
|
.Sh NAME
|
|
.Nm pmc_read ,
|
|
.Nm pmc_rw ,
|
|
.Nm pmc_write ,
|
|
.Nd read and write hardware performance counters
|
|
.Sh LIBRARY
|
|
.Lb libpmc
|
|
.Sh SYNOPSIS
|
|
.In pmc.h
|
|
.Ft int
|
|
.Fn pmc_read "pmc_id_t pmc" "pmc_value_t *value"
|
|
.Ft int
|
|
.Fn pmc_rw "pmc_id_t pmc" "pmc_value_t newvalue" "pmc_value_t *oldvaluep"
|
|
.Ft int
|
|
.Fn pmc_write "pmc_id_t pmc" "pmc_value_t value"
|
|
.Sh DESCRIPTION
|
|
These functions read and write the current value of a PMC.
|
|
.Pp
|
|
Function
|
|
.Fn pmc_read
|
|
with read the current value of the PMC specified by argument
|
|
.Fa pmc
|
|
and write it to the location specified by argument
|
|
.Fa value .
|
|
.Pp
|
|
Function
|
|
.Fn pmc_write
|
|
will set the current value of the PMC specified by argument
|
|
.Fa pmc
|
|
to the value specified by argument
|
|
.Fa value .
|
|
.Pp
|
|
Function
|
|
.Fn pmc_rw
|
|
combines a read and a write into a single atomic operation.
|
|
.Pp
|
|
For write operations the PMC should be a quiescent state.
|
|
.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
|
|
A write operation specified a currently running PMC.
|
|
.It Bq Er EINVAL
|
|
Argument
|
|
.Fa pmc
|
|
specified a PMC not in a readable state.
|
|
.It Bq Er EINVAL
|
|
The PMC specified by argument
|
|
.Fa pmc
|
|
was not owned by the current process.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr pmc 3 ,
|
|
.Xr hwpmc 4
|