/* This file performs the following test: each OMP thread measures flops

for its provided tasks, and compares this to expected flop counts, each

thread having been provided with a random amount of work, such that the

time and order that they complete their measurements varies.

Specifically tested is the case where the value returned for some threads

actually corresponds to that for another thread reading its counter values

at the same time.

   - It is based on zero_omp.c but ignored much of its functionality.

   - It attempts to use the following two counters. It may use less

depending on hardware counter resource limitations. These are counted

in the default counting domain and default granularity, depending on

the platform. Usually this is the user domain (PAPI_DOM_USER) and

thread context (PAPI_GRN_THR).

     + PAPI_FP_INS

     + PAPI_TOT_CYC

Each thread inside the Thread routine:

   - Do prework (MAX_FLOPS - flops)

   - Get cyc.

   - Get us.

   - Start counters

   - Do flops

   - Stop and read counters

   - Get us.

   - Get cyc.

   - Return flops

*/

#include "papi_test.h"

#ifdef _OPENMP

#include <omp.h>

#else

#error "This compiler does not understand OPENMP"

#endif

const int MAX_FLOPS = NUM_FLOPS;

extern int TESTS_QUIET;				   /* Declared in test_utils.c */

const PAPI_hw_info_t *hw_info = NULL;

long long

Thread( int n )

{

	int retval, num_tests = 1;

	int EventSet1 = PAPI_NULL;

	int PAPI_event, mask1;

	int num_events1;

	long long flops;

	long long **values;

	long long elapsed_us, elapsed_cyc;

	char event_name[PAPI_MAX_STR_LEN];

	/* printf("Thread(n=%d) %#x started\n", n, omp_get_thread_num()); */

	num_events1 = 2;

	/* add PAPI_TOT_CYC and one of the events in PAPI_FP_INS, PAPI_FP_OPS or

	   PAPI_TOT_INS, depending on the availability of the event on the

	   platform */

	EventSet1 = add_two_events( &num_events1, &PAPI_event, &mask1 );

	retval = PAPI_event_code_to_name( PAPI_event, event_name );

	if ( retval != PAPI_OK )

		test_fail( __FILE__, __LINE__, "PAPI_event_code_to_name", retval );

	values = allocate_test_space( num_tests, num_events1 );

	do_flops( MAX_FLOPS - n );	/* prework for balance */

	elapsed_us = PAPI_get_real_usec(  );

	elapsed_cyc = PAPI_get_real_cyc(  );

	retval = PAPI_start( EventSet1 );

	if ( retval != PAPI_OK )

		test_fail( __FILE__, __LINE__, "PAPI_start", retval );

	do_flops( n );

	retval = PAPI_stop( EventSet1, values[0] );

	if ( retval != PAPI_OK )

		test_fail( __FILE__, __LINE__, "PAPI_stop", retval );

	flops = ( values[0] )[0];

	elapsed_us = PAPI_get_real_usec(  ) - elapsed_us;

	elapsed_cyc = PAPI_get_real_cyc(  ) - elapsed_cyc;

	remove_test_events( &EventSet1, mask1 );

	if ( !TESTS_QUIET ) {

		/*printf("Thread %#x %-12s : \t%lld\t%d\n", omp_get_thread_num(), event_name,

		   (values[0])[0], n); */

#if 0

		printf( "Thread %#x PAPI_TOT_CYC: \t%lld\n", omp_get_thread_num(  ),

				values[0][0] );

		printf( "Thread %#x Real usec   : \t%lld\n", omp_get_thread_num(  ),

				elapsed_us );

		printf( "Thread %#x Real cycles : \t%lld\n", omp_get_thread_num(  ),

				elapsed_cyc );

#endif

	}

	/* It is illegal for the threads to exit in OpenMP */

	/* test_pass(__FILE__,0,0); */

	free_test_space( values, num_tests );

	PAPI_unregister_thread(  );

	/* printf("Thread %#x finished\n", omp_get_thread_num()); */

	return flops;

}

int

main( int argc, char **argv )

{

	int tid, retval;

	int maxthr = omp_get_max_threads(  );

	int flopper = 0;

	long long *flops = calloc( maxthr, sizeof ( long long ) );

	long long *flopi = calloc( maxthr, sizeof ( long long ) );

	tests_quiet( argc, argv );	/* Set TESTS_QUIET variable */

	if ( maxthr < 2 )

		test_skip( __FILE__, __LINE__, "omp_get_num_threads < 2", PAPI_EINVAL );

	if ( ( flops == NULL ) || ( flopi == NULL ) )

		test_fail( __FILE__, __LINE__, "calloc", PAPI_ENOMEM );

	retval = PAPI_library_init( PAPI_VER_CURRENT );

	if ( retval != PAPI_VER_CURRENT )

		test_fail( __FILE__, __LINE__, "PAPI_library_init", retval );

	hw_info = PAPI_get_hardware_info(  );

	if ( hw_info == NULL )

		test_fail( __FILE__, __LINE__, "PAPI_get_hardware_info", 2 );

	retval =

		PAPI_thread_init( ( unsigned

							long ( * )( void ) ) ( omp_get_thread_num ) );

	if ( retval != PAPI_OK )

		if ( retval == PAPI_ECMP )

			test_skip( __FILE__, __LINE__, "PAPI_thread_init", retval );

		else

			test_fail( __FILE__, __LINE__, "PAPI_thread_init", retval );

	flopper = Thread( 65536 ) / 65536;

	printf( "flopper=%d\n", flopper );

	for ( int i = 0; i < 100000; i++ )

#pragma omp parallel private(tid)

	{

		tid = omp_get_thread_num(  );

		flopi[tid] = rand(  ) * 3;

		flops[tid] = Thread( ( flopi[tid] / flopper ) % MAX_FLOPS );

#pragma omp barrier

#pragma omp master

		if ( flops[tid] < flopi[tid] ) {

			printf( "test iteration=%d\n", i );

			for ( int j = 0; j < omp_get_num_threads(  ); j++ ) {

				printf( "Thread %#x Value %6lld %c %6lld", j, flops[j],

						( flops[j] < flopi[j] ) ? '<' : '=', flopi[j] );

				for ( int k = 0; k < omp_get_num_threads(  ); k++ )

					if ( ( k != j ) && ( flops[k] == flops[j] ) )

						printf( " == Thread %#x!", k );

				printf( "\n" );

			}

			test_fail( __FILE__, __LINE__, "value returned for thread",

					   PAPI_EBUG );

		}

	}

	test_pass( __FILE__, NULL, 0 );

	exit( 0 );

}