| Current Path : /compat/linux/proc/68247/cwd/usr/src/lib/libpmc/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //compat/linux/proc/68247/cwd/usr/src/lib/libpmc/pmc_read.3 |
.\" 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 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: release/9.1.0/lib/libpmc/pmc_read.3 232151 2012-02-25 10:10:43Z brueffer $ .\" .Dd November 25, 2007 .Dt PMC_READ 3 .Os .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 will 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