papi_cost.c

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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "papi.h"
#include "cost_utils.h"

/* Search for a derived event of type "type" */
static int
find_derived( int i , char *type)
{
    PAPI_event_info_t info;

    PAPI_enum_event( &i, PAPI_ENUM_FIRST );

    do {
        if ( PAPI_get_event_info( i, &info ) == PAPI_OK ) {

            if ( strcmp( info.derived, type) == 0 ) {
                return i;
            }
        }
    } while ( PAPI_enum_event( &i, PAPI_PRESET_ENUM_AVAIL ) == PAPI_OK );

    return PAPI_NULL;
}

/* Slight misnomer, find derived event != DERIVED_POSTFIX */
/* Will look for DERIVED_ADD, if not available will also accept DERIVED_SUB */
static int
find_derived_add( int i )
{
    int ret;

    ret = find_derived( i, "DERIVED_ADD");
    if (ret != PAPI_NULL) {
        return ret;
    }

    return find_derived( i, "DERIVED_SUB");
}

static int
find_derived_postfix( int i )
{
  return ( find_derived ( i, "DERIVED_POSTFIX" ) );
}

static void
print_help( void )
{
    printf( "This is the PAPI cost program.\n" );
    printf( "It computes min / max / mean / std. deviation for PAPI start/stop pairs; for PAPI reads, and for PAPI_accums.  Usage:\n\n" );
    printf( "    cost [options] [parameters]\n" );
    printf( "    cost TESTS_QUIET\n\n" );
    printf( "Options:\n\n" );
    printf( "  -b BINS       set the number of bins for the graphical distribution of costs. Default: 100\n" );
    printf( "  -d            show a graphical distribution of costs\n" );
    printf( "  -h            print this help message\n" );
    printf( "  -p            print 25/50/75th percentile results for making boxplots\n");
    printf( "  -s            show number of iterations above the first 10 std deviations\n" );
    printf( "  -t THRESHOLD  set the threshold for the number of iterations. Default: 1,000,000\n" );
    printf( "\n" );
}


static void
print_stats( int i, long long min, long long max, double average, double std )
{
    char *test[] = {
        "loop latency",
        "PAPI_start/stop (2 counters)",
        "PAPI_read (2 counters)",
        "PAPI_read_ts (2 counters)",
        "PAPI_accum (2 counters)",
        "PAPI_reset (2 counters)",
        "PAPI_read (1 derived_postfix counter)",
        "PAPI_read (1 derived_[add|sub] counter)"
    };

    printf( "\nTotal cost for %s over %d iterations\n",
        test[i], num_iters );
    printf( "min cycles   : %lld\nmax cycles   : %lld\n"
        "mean cycles  : %lf\nstd deviation: %lf\n",
        min, max, average, std );
}

static void
print_std_dev( int *s )
{
    int i;

    printf( "\n" );
    printf( "              --------# Standard Deviations Above the Mean--------\n" );
    printf( "0-------1-------2-------3-------4-------5-------6-------7-------8-------9-----10\n" );
    for ( i = 0; i < 10; i++ )
        printf( "  %d\t", s[i] );
    printf( "\n\n" );
}

static void
print_dist( long long min, long long max, int bins, int *d )
{
    int i, j;
    int step = ( int ) ( max - min ) / bins;

    printf( "\nCost distribution profile\n\n" );
    for ( i = 0; i < bins; i++ ) {
        printf( "%8d:", ( int ) min + ( step * i ) );
        if ( d[i] > 100 ) {
            printf( "**************************** %d counts ****************************",
                  d[i] );
        } else {
            for ( j = 0; j < d[i]; j++ )
                printf( "*" );
        }
        printf( "\n" );
    }
}

static void
print_percentile(long long percent25, long long percent50,
        long long percent75,long long percent99)
{
    printf("25%% cycles   : %lld\n50%% cycles   : %lld\n"
        "75%% cycles   : %lld\n99%% cycles   : %lld\n",
        percent25,percent50,percent75,percent99);
}

static void
do_output( int test_type, long long *array, int bins, int show_std_dev,
           int show_dist, int show_percentile )
{
    int s[10];
    long long min, max;
    double average, std;
    long long percent25,percent50,percent75,percent99;

    std = do_stats( array, &min, &max, &average );
    print_stats( test_type, min, max, average, std );

    if (show_percentile) {
        do_percentile(array,&percent25,&percent50,&percent75,&percent99);
        print_percentile(percent25,percent50,percent75,percent99);
    }

    if ( show_std_dev ) {
        do_std_dev( array, s, std, average );
        print_std_dev( s );
    }

    if ( show_dist ) {
        int *d;
        d = calloc( bins , sizeof ( int ) );
        do_dist( array, min, max, bins, d );
        print_dist( min, max, bins, d );
        free( d );
    }
}


int
main( int argc, char **argv )
{
    int i, retval, EventSet = PAPI_NULL;
    int retval_start,retval_stop;
    int bins = 100;
    int show_dist = 0, show_std_dev = 0, show_percent = 0;
    long long totcyc, values[2];
    long long *array;
    int event;
    PAPI_event_info_t info;
    int c;

    /* Check command-line arguments */

    while ( (c=getopt(argc, argv, "hb:dpst:") ) != -1) {

        switch(c) {

            case 'h':
                print_help();
                exit(1);
            case 'b':
                bins=atoi(optarg);
                break;
            case 'd':
                show_dist=1;
                break;
            case 'p':
                show_percent=1;
                break;
            case 's':
                show_std_dev=1;
                break;
            case 't':
                num_iters=atoi(optarg);
                break;
            default:
                print_help();
                exit(1);
                break;
        }

    }

    printf( "Cost of execution for PAPI start/stop, read and accum.\n" );
    printf( "This test takes a while. Please be patient...\n" );

    retval = PAPI_library_init( PAPI_VER_CURRENT );
    if (retval != PAPI_VER_CURRENT ) {
        fprintf(stderr,"PAPI_library_init\n");
        exit(retval);
    }
    retval = PAPI_set_debug( PAPI_VERB_ECONT );
    if (retval != PAPI_OK ) {
        fprintf(stderr,"PAPI_set_debug\n");
        exit(retval);
    }
    retval = PAPI_query_event( PAPI_TOT_CYC );
    if (retval != PAPI_OK ) {
        fprintf(stderr,"PAPI_query_event\n");
        exit(retval);
    }
    retval = PAPI_query_event( PAPI_TOT_INS );
    if (retval != PAPI_OK ) {
        fprintf(stderr,"PAPI_query_event\n");
        exit(retval);
    }
    retval = PAPI_create_eventset( &EventSet );
    if (retval != PAPI_OK ) {
        fprintf(stderr,"PAPI_create_eventset\n");
        exit(retval);
    }
    retval = PAPI_add_event( EventSet, PAPI_TOT_CYC );
    if (retval != PAPI_OK ) {
        fprintf(stderr,"PAPI_add_event\n");
        exit(retval);
    }
    retval = PAPI_add_event( EventSet, PAPI_TOT_INS );
    if (retval != PAPI_OK ) {
        retval = PAPI_add_event( EventSet, PAPI_TOT_IIS );
        if (retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_add_event\n");
            exit(retval);
        }
    }

    /* Make sure no errors and warm up */

    totcyc = PAPI_get_real_cyc(  );
    if ( ( retval = PAPI_start( EventSet ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_start");
        exit(retval);
    }
    if ( ( retval = PAPI_stop( EventSet, NULL ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_stop");
        exit(retval);
    }

    array = ( long long * ) malloc( ( size_t ) num_iters * sizeof ( long long ) );
    if ( array == NULL ) {
        fprintf(stderr,"Error allocating memory for results\n");
        exit(retval);
    }

    /* Determine clock latency */

    printf( "\nPerforming loop latency test...\n" );

    for ( i = 0; i < num_iters; i++ ) {
        totcyc = PAPI_get_real_cyc(  );
        totcyc = PAPI_get_real_cyc(  ) - totcyc;
        array[i] = totcyc;
    }

    do_output( 0, array, bins, show_std_dev, show_dist, show_percent );

    /* Start the start/stop eval */

    printf( "\nPerforming start/stop test...\n" );

    for ( i = 0; i < num_iters; i++ ) {
        totcyc = PAPI_get_real_cyc(  );
        retval_start=PAPI_start( EventSet );
        retval_stop=PAPI_stop( EventSet, values );
        totcyc = PAPI_get_real_cyc(  ) - totcyc;
        array[i] = totcyc;
        if (retval_start || retval_stop) {
           fprintf(stderr,"PAPI start/stop\n");
            exit(retval_start );
        }
    }

    do_output( 1, array, bins, show_std_dev, show_dist, show_percent );

    /* Start the read eval */
    printf( "\nPerforming read test...\n" );

    if ( ( retval = PAPI_start( EventSet ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_start");
        exit(retval);
    }
    PAPI_read( EventSet, values );

    for ( i = 0; i < num_iters; i++ ) {
        totcyc = PAPI_get_real_cyc(  );
        PAPI_read( EventSet, values );
        totcyc = PAPI_get_real_cyc(  ) - totcyc;
        array[i] = totcyc;
    }
    if ( ( retval = PAPI_stop( EventSet, values ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_stop");
        exit(retval);
    }

    do_output( 2, array, bins, show_std_dev, show_dist, show_percent );

    /* Start the read with timestamp eval */
    printf( "\nPerforming read with timestamp test...\n" );

    if ( ( retval = PAPI_start( EventSet ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_start");
        exit(retval);
    }
    PAPI_read_ts( EventSet, values, &totcyc );

    for ( i = 0; i < num_iters; i++ ) {
        PAPI_read_ts( EventSet, values, &array[i] );
    }
    if ( ( retval = PAPI_stop( EventSet, values ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_stop");
        exit(retval);
    }

    /* post-process the timing array */
    for ( i = num_iters - 1; i > 0; i-- ) {
        array[i] -= array[i - 1];
    }
    array[0] -= totcyc;

    do_output( 3, array, bins, show_std_dev, show_dist, show_percent );

    /* Start the accum eval */
    printf( "\nPerforming accum test...\n" );

    if ( ( retval = PAPI_start( EventSet ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_start");
        exit(retval);
    }
    PAPI_accum( EventSet, values );

    for ( i = 0; i < num_iters; i++ ) {
        totcyc = PAPI_get_real_cyc(  );
        PAPI_accum( EventSet, values );
        totcyc = PAPI_get_real_cyc(  ) - totcyc;
        array[i] = totcyc;
    }
    if ( ( retval = PAPI_stop( EventSet, values ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_stop");
        exit(retval);
    }

    do_output( 4, array, bins, show_std_dev, show_dist, show_percent );

    /* Start the reset eval */
    printf( "\nPerforming reset test...\n" );

    if ( ( retval = PAPI_start( EventSet ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_start");
        exit(retval);
    }

    for ( i = 0; i < num_iters; i++ ) {
        totcyc = PAPI_get_real_cyc(  );
        PAPI_reset( EventSet );
        totcyc = PAPI_get_real_cyc(  ) - totcyc;
        array[i] = totcyc;
    }
    if ( ( retval = PAPI_stop( EventSet, values ) ) != PAPI_OK ) {
        fprintf(stderr,"PAPI_stop");
        exit(retval);
    }

    do_output( 5, array, bins, show_std_dev, show_dist, show_percent );

    /* Derived POSTFIX event test */
    PAPI_cleanup_eventset( EventSet );

    event = 0 | PAPI_PRESET_MASK;

    event = find_derived_postfix( event );
    if ( event != PAPI_NULL ) {

        PAPI_get_event_info(event, &info);
        printf( "\nPerforming DERIVED_POSTFIX "
            "PAPI_read(%d counters)  test (%s)...",
            info.count, info.symbol );

        retval = PAPI_add_event( EventSet, event);
        if ( retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_add_event");
            exit(retval);
        }

        retval = PAPI_start( EventSet );
        if ( retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_start");
            exit(retval);
        }

        PAPI_read( EventSet, values );

        for ( i = 0; i < num_iters; i++ ) {
            totcyc = PAPI_get_real_cyc(  );
            PAPI_read( EventSet, values );
            totcyc = PAPI_get_real_cyc(  ) - totcyc;
            array[i] = totcyc;
        }

        retval = PAPI_stop( EventSet, values );
        if ( retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_stop");
            exit(retval);
        }

        do_output( 6, array, bins, show_std_dev, show_dist, show_percent );

    } else {
        printf("\tI was unable to find a DERIVED_POSTFIX preset event "
            "to test on this architecture, skipping.\n");
    }

    /* Find a derived ADD event */
    PAPI_cleanup_eventset( EventSet );

    event = 0 | PAPI_PRESET_MASK;

    event = find_derived_add( event );
    if ( event != PAPI_NULL ) {

        PAPI_get_event_info(event, &info);
        printf( "\nPerforming DERIVED_[ADD|SUB] "
            "PAPI_read(%d counters)  test (%s)...",
            info.count, info.symbol );

        retval = PAPI_add_event( EventSet, event);
        if ( retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_add_event\n");
            exit(retval);
        }

        retval = PAPI_start( EventSet );
        if ( retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_start");
            exit(retval);
        }

        PAPI_read( EventSet, values );

        for ( i = 0; i < num_iters; i++ ) {
            totcyc = PAPI_get_real_cyc(  );
            PAPI_read( EventSet, values );
            totcyc = PAPI_get_real_cyc(  ) - totcyc;
            array[i] = totcyc;
        }

        retval = PAPI_stop( EventSet, values );
        if ( retval != PAPI_OK ) {
            fprintf(stderr,"PAPI_stop");
            exit(retval);
        }

        do_output( 7, array, bins, show_std_dev, show_dist, show_percent );
    } else {
        printf("\tI was unable to find a suitable DERIVED_[ADD|SUB] "
            "event to test, skipping.\n");
    }

    free( array );

    return 0;
}