PAPI_start - Online Linux Manual Page

Section : 3
Updated : September, 2004
Source : PAPI Programmer's Reference
Note : PAPI

NAME

PAPI_start − start counting hardware events in an event set

PAPI_stop − stop counting hardware events in an event set

SYNOPSIS

C Interface

#include <papi.h>

int PAPI_start(int

EventSet

);

int PAPI_stop(int

EventSet

, long_long *

values

);

Fortran Interface

#include "fpapi.h"

PAPIF_start(C_INT

EventSet,

C_INT

check

)

PAPIF_stop(C_INT

EventSet,

C_LONG_LONG(*)

values,

C_INT

check

)

DESCRIPTION

PAPI_start starts counting all of the hardware events contained in the previously defined EventSet. All counters are implicitly set to zero before counting.

PAPI_stop halts the counting of a previously defined event set and the counter values contained in that EventSet are copied into the values array

These calls assume an initialized PAPI library and a properly added event set.

ARGUMENTS

EventSet" -- an integer handle for a PAPI event set as created by

PAPI_create_eventset(3)

*values -- an array to hold the counter values of the counting events

RETURN VALUES

On success, this function returns PAPI_OK."
On error, a non-zero error code is returned.

ERRORS

PAPI_EINVAL"

One or more of the arguments is invalid.

PAPI_ESYS"

A system or C library call failed inside PAPI, see the errno" variable.

PAPI_ENOEVST"

The EventSet specified does not exist.

PAPI_EISRUN"

The EventSet is currently counting events.

(

PAPI_start()

only)

PAPI_ENOTRUN"

The EventSet is currently not running.

(

PAPI_stop()

only)

PAPI_ECNFLCT"

The underlying counter hardware can not count this event and other events in the EventSet simultaneously.

(

PAPI_start()

only)

PAPI_ENOEVNT"

The PAPI preset is not available on the underlying hardware.

EXAMPLES

  if (PAPI_create_eventset(&EventSet) != PAPI_OK)
    handle_error(1);

  /* Add Total Instructions Executed to our EventSet */
  if (PAPI_add_event(EventSet, PAPI_TOT_INS) != PAPI_OK)
    handle_error(1);

  /* Start counting */
  if (PAPI_start(EventSet) != PAPI_OK)
    handle_error(1);

  poorly_tuned_function();

  if (PAPI_stop(EventSet, values) != PAPI_OK)
    handle_error(1);

  printf("%lld\n",values[0]);

BUGS

These functions have no known bugs.