PAPI_read (3) Linux Manual Page
PAPI_read –
Read hardware counters from an event set.
Synopsis
Detailed Description
C Interface:- #include <papi.h>
int PAPI_read(int EventSet, long_long * values )
PAPI_read() copies the counters of the indicated event set into the provided array.
The counters continue counting after the read.
Note the differences between PAPI_read() and PAPI_accum(), specifically that PAPI_accum() resets the values array to zero.
PAPI_read() assumes an initialized PAPI library and a properly added event set.
Parameters:
- EventSet — an integer handle for a PAPI Event Set as created by PAPI_create_eventset()
*values — an array to hold the counter values of the counting events
Return values:
- 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 event set specified does not exist.
Examples
* do_100events();
* if (PAPI_read(EventSet, values) != PAPI_OK)
* handle_error(1);
* // values[0] now equals 100
* do_100events();
* if (PAPI_accum(EventSet, values) != PAPI_OK)
* handle_error(1);
* // values[0] now equals 200
* values[0] = -100;
* do_100events();
* if (PAPI_accum(EventSet, values) != PAPI_OK)
* handle_error(1);
* // values[0] now equals 0
*
See Also:
- PAPI_accum
PAPI_start
PAPI_stop
PAPI_reset