For a fixed number of parameters (of a limited range of types), pretty much exactly as you would calling the C function from another piece of C code. (The required mappings to extract integers, doubles, string pointers etc. are done for you under the covers.)

#! perl -slw
use strict;
use Time::HiRes qw[ time ];
use Inline C => Config => BUILD_NOISY => 1;
use Inline C => <<'END_C',  NAME => '_729090', CLEAN_AFTER_BUILD => 0;

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

SV* thing( int stepI, int limitJ ) {
    int i, j;

    for( i = stepI; ; i += stepI ) {
        for( j = 1; j < limitJ; j++) {
            if( i % j ) break;
        }
        if( j == limitJ ) {
            return newSViv( i );
            break;
        }
    }
}

END_C

my $start = time;
print thing( @ARGV );
print time - $start;

__END__
C:\test>729090-IC 15 15
360360
0.00263190269470215

C:\test>729090-IC 20 20
232792560
1.421875

C:\test>729090-IC 23 23
698377680
30.453125
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If you want to pass a list al la Perl subs, then it gets a bit more complex. Then you have to start manipulating the Perl stack yourself. Likewise if you want to return more than the C normal of one parameter.