1.\" Copyright (c) 2007 Joseph Koshy. All rights reserved. 2.\" 3.\" Redistribution and use in source and binary forms, with or without 4.\" modification, are permitted provided that the following conditions 5.\" are met: 6.\" 1. Redistributions of source code must retain the above copyright 7.\" notice, this list of conditions and the following disclaimer. 8.\" 2. Redistributions in binary form must reproduce the above copyright 9.\" notice, this list of conditions and the following disclaimer in the 10.\" documentation and/or other materials provided with the distribution. 11.\" 12.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 13.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 14.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 15.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 16.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 17.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 18.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 19.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 20.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 21.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 22.\" SUCH DAMAGE. 23.\" 24.Dd November 25, 2007 25.Dt PMC_GET_MSR 3 26.Os 27.Sh NAME 28.Nm pmc_get_msr 29.Nd x86 architecture-specific PMC operations 30.Sh LIBRARY 31.Lb libpmc 32.Sh SYNOPSIS 33.In pmc.h 34.Ft int 35.Fn pmc_get_msr "pmc_id_t pmc" "uint32_t *msr" 36.Sh DESCRIPTION 37The function 38.Fn pmc_get_msr 39returns the processor model specific register number associated with 40a PMC for subsequent use with RDPMC instructions. 41Argument 42.Fa pmc 43specifies a process scope counting PMC. 44The function will write the model specific register number associated 45with the PMC to the location pointed to by argument 46.Fa msr . 47.Pp 48After successful completion of this function, applications 49can directly read the contents of PMC hardware using 50RDPMC instructions. 51.Sh RETURN VALUES 52.Rv -std pmc_get_msr 53.Sh ERRORS 54A call to 55.Fn pmc_get_msr 56may fail with the following errors: 57.Bl -tag -width Er 58.It Bq Er EINVAL 59The PMC handle specified was invalid. 60.It Bq Er EINVAL 61The PMC specified did not have process scope or counting mode. 62.It Bq Er EINVAL 63The PMC specified was allocated with the 64.Dv PMC_F_DESCENDANTS 65flag. 66.It Bq Er EINVAL 67The specified PMC is already attached to target processes other 68than the owner. 69.It Bq Er ENOSYS 70The underlying hardware does not support an RDPMC instruction. 71.El 72.Sh SEE ALSO 73.Xr pmc 3 , 74.Xr hwpmc 4 75