pmc_stop(3) [freebsd man page]

PMC_START(3)						   BSD Library Functions Manual 					      PMC_START(3)

NAME

     pmc_start, pmc_stop -- start and stop a PMC

LIBRARY

     Performance Counters Library (libpmc, -lpmc)

SYNOPSIS

     #include <pmc.h>

     int
     pmc_start(pmc_id_t pmc);

     int
     pmc_stop(pmc_id_t pmc);

DESCRIPTION

     These functions are used to start and stop a PMC.

     Function pmc_start() starts the PMC specified by argument pmc.  If the specified PMC has process scope and has not been attached to any tar-
     gets, it will be attached to the current process.

     Function pmc_stop() stops the PMC specified by argument pmc.

RETURN VALUES

     Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the
     error.

ERRORS

     A call to these functions may fail with the following errors:

     [EDOOFUS]		Function pmc_start() specified a PMC that requires a log file and no log file was configured.

     [EINVAL]		The specified PMC is in the process of being deleted.

     [EINVAL]		Function pmc_stop() specified a PMC that was never started.

     [ENXIO]		The specified PMC had system scope and its associated CPU was disabled or absent.

SEE ALSO

     pmc(3), hwpmc(4)

BSD
								September 22, 2008							       BSD

PMC_READ(3)						   BSD Library Functions Manual 					       PMC_READ(3)

NAME

     pmc_read, pmc_rw, pmc_write, -- read and write hardware performance counters

LIBRARY

     Performance Counters Library (libpmc, -lpmc)

SYNOPSIS

     #include <pmc.h>

     int
     pmc_read(pmc_id_t pmc, pmc_value_t *value);

     int
     pmc_rw(pmc_id_t pmc, pmc_value_t newvalue, pmc_value_t *oldvaluep);

     int
     pmc_write(pmc_id_t pmc, pmc_value_t value);

DESCRIPTION

     These functions read and write the current value of a PMC.

     Function pmc_read() will read the current value of the PMC specified by argument pmc and write it to the location specified by argument
     value.

     Function pmc_write() will set the current value of the PMC specified by argument pmc to the value specified by argument value.

     Function pmc_rw() combines a read and a write into a single atomic operation.

     For write operations the PMC should be a quiescent state.

RETURN VALUES

     Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the
     error.

ERRORS

     A call to these functions may fail with the following errors:

     [EBUSY]		A write operation specified a currently running PMC.

     [EINVAL]		Argument pmc specified a PMC not in a readable state.

     [EINVAL]		The PMC specified by argument pmc was not owned by the current process.

SEE ALSO

     pmc(3), hwpmc(4)

BSD
								 November 25, 2007							       BSD