overflow_values.c

Go to the documentation of this file.

/* 
* File:    overflow_values.c
* CVS:     $Id$
* Author:  Harald Servat
*          harald@cepba.upc.edu
* Mods:    <your name here>
*          <your email address>
*/
 
/* This file performs the following test: overflow values check
 
     The Eventset contains:
     + PAPI_TOT_INS (overflow monitor)
     + PAPI_TOT_CYC
     + PAPI_L1_DCM
 
   - Start eventset
   - Read and report event counts mod 1000
   - report overflow event counts
   - visually inspect for consistency
   - Stop eventset
*/
 
#include "papi_test.h"
 
#define OVRFLOW 5000000
#define LOWERFLOW (OVRFLOW - (OVRFLOW/100))
#define UPPERFLOW (OVRFLOW/100)
#define ERRORFLOW (UPPERFLOW/5)
static long long ovrflow = 0;
 
void
handler( int EventSet, void *address, long long overflow_vector, void *context )
{
    int ret;
    int i;
    long long vals[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
 
    printf( "\nOverflow at %p! bit=%#llx \n", address, overflow_vector );
    ret = PAPI_read( EventSet, vals );
    printf( "Overflow read vals :" );
    for ( i = 0; i < 3 /* 8 */ ; i++ )
        printf( "%lld ", vals[i] );
    printf( "\n\n" );
    ovrflow = vals[0];
}
 
int
main( int argc, char *argv[] )
{
    int EventSet = PAPI_NULL;
    int retval, i, dash = 0, evt3 = PAPI_L1_DCM;
    PAPI_option_t options;
    PAPI_option_t options2;
    const PAPI_hw_info_t *hwinfo;
    long long lwrflow = 0, error, max_error = 0;
    long long vals[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
 
    tests_quiet( argc, argv );  /* Set TESTS_QUIET variable */
 
    retval = PAPI_library_init( PAPI_VER_CURRENT );
    if ( retval != PAPI_VER_CURRENT && retval > 0 )
        test_fail( __FILE__, __LINE__, "PAPI_library_init", retval );
 
    retval = PAPI_get_opt( PAPI_HWINFO, &options );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_get_opt", retval );
    printf( "ovf_info = %d (%#x)\n", options.ovf_info.type,
            options.ovf_info.type );
 
    retval = PAPI_get_opt( PAPI_SUBSTRATEINFO, &options2 );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_get_opt", retval );
    printf( "sub_info->hardware_intr = %d\n\n",
            options2.sub_info->hardware_intr );
 
    if ( ( hwinfo = PAPI_get_hardware_info(  ) ) == NULL )
        test_fail( __FILE__, __LINE__, "PAPI_get_hardware_info", PAPI_EMISC );
 
    printf( "Architecture %s, %d\n", hwinfo->model_string, hwinfo->model );
 
/* processing exceptions is a pain */
#if ((defined(linux) && (defined(__i386__) || (defined __x86_64__))) )
    if ( !strncmp( hwinfo->model_string, "Intel Pentium 4", 15 ) ) {
        evt3 = PAPI_L2_TCM;
    } else if ( !strncmp( hwinfo->model_string, "AMD K7", 6 ) ) {
        /* do nothing */
    } else if ( !strncmp( hwinfo->model_string, "AMD K8", 6 ) ) {
        /* do nothing */
    } else if ( !strncmp( hwinfo->model_string, "Intel Core", 10 ) ) {
        evt3 = 0;
    } else
        evt3 = 0;            /* for default PIII */
#endif
 
    retval = PAPI_create_eventset( &EventSet );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_create_eventset", retval );
 
    retval = PAPI_add_event( EventSet, PAPI_TOT_INS );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_add_event:PAPI_TOT_INS", retval );
    retval = PAPI_add_event( EventSet, PAPI_TOT_CYC );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_add_event:PAPI_TOT_CYC", retval );
    if ( evt3 ) {
        retval = PAPI_add_event( EventSet, evt3 );
        if ( retval < 0 )
            test_fail( __FILE__, __LINE__, "PAPI_add_event:evt3", retval );
    }
    retval = PAPI_overflow( EventSet, PAPI_TOT_INS, OVRFLOW, 0, handler );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_overflow", retval );
 
    retval = PAPI_start( EventSet );
    if ( retval < 0 )
        test_fail( __FILE__, __LINE__, "PAPI_start", retval );
 
    for ( i = 0; i < 1000000; i++ ) {
        if ( i % 1000 == 0 ) {
            int i;
 
            PAPI_read( EventSet, vals );
            if ( vals[0] % OVRFLOW > LOWERFLOW ||
                 vals[0] % OVRFLOW < UPPERFLOW ) {
                dash = 0;
                printf( "Main loop read vals :" );
                for ( i = 0; i < 3 /* 8 */ ; i++ )
                    printf( "%lld ", vals[i] );
                printf( "\n" );
                if ( ovrflow ) {
                    error = ovrflow - ( lwrflow + vals[0] ) / 2;
                    printf( "Difference: %lld\n", error );
                    ovrflow = 0;
                    if ( abs( error ) > max_error )
                        max_error = abs( error );
                }
                lwrflow = vals[0];
            } else if ( vals[0] % OVRFLOW > UPPERFLOW && !dash ) {
                dash = 1;
                printf( "---------------------\n" );
            }
        }
    }
 
    retval = PAPI_stop( EventSet, vals );
    if ( retval != PAPI_OK )
        test_fail( __FILE__, __LINE__, "PAPI_stop", retval );
 
    retval = PAPI_cleanup_eventset( EventSet );
    if ( retval != PAPI_OK )
        test_fail( __FILE__, __LINE__, "PAPI_cleanup_eventset", retval );
 
    retval = PAPI_destroy_eventset( &EventSet );
    if ( retval != PAPI_OK )
        test_fail( __FILE__, __LINE__, "PAPI_destroy_eventset", retval );
 
    printf( "Verification:\n" );
    printf
        ( "Maximum absolute difference between overflow value\nand adjacent measured values is: %lld\n",
          max_error );
    if ( max_error >= ERRORFLOW ) {
        printf( "This exceeds the error limit: %d\n", ERRORFLOW );
        test_fail( __FILE__, __LINE__, "Overflows", 1 );
    }
    printf( "This is within the error limit: %d\n", ERRORFLOW );
    test_pass( __FILE__, NULL, 0 );
    exit( 1 );
}