atomic_compare_swap_neq.c

/*
 * Copyright (c) 2016 U.S. Army Research laboratory. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * This software was developed by Brown Deer Technology, LLC. with Copyright
 * assigned to the US Army Research laboratory as required by contract.
 */

/*
 * Performance test for shmem_int_atomic_compare_swap
 */

#include <host_stdio.h>
#include <shmem.h>
#include "ctimer.h"

#ifndef NLOOP
#define NLOOP 1024
#endif

int main (void)
{
	int i, npe;
	static int dest, ti, tsum;
	static int pWrk[SHMEM_REDUCE_MIN_WRKDATA_SIZE];
	static long pSync[SHMEM_REDUCE_SYNC_SIZE];
	for (i = 0; i < SHMEM_REDUCE_SYNC_SIZE; i++) {
		pSync[i] = SHMEM_SYNC_VALUE;
	}

	shmem_init();
	int me = shmem_my_pe();
	int npes = shmem_n_pes();
	dest = me;

	if (me == 0) {
		host_printf("# SHMEM Atomic Compare-and-Swap (not equal) Performance for variable NPES\n" \
			"# NPES\tLatency (nanoseconds)\n");
	}

	for (npe = 1; npe <= npes; npe++)
	{
		int nxtpe = me + 1;
		if (nxtpe >= npe) nxtpe -= npe;

		int cond = -1;

		shmem_barrier_all();

		if (me < npe) {
			ctimer_start();
			unsigned int t = ctimer();

			for (i = 0; i < NLOOP; i++) {
				shmem_atomic_compare_swap(&dest, cond, nxtpe, nxtpe);
			}

			t -= ctimer();
			ti = (int)t;
			shmem_int_sum_to_all(&tsum, &ti, 1, 0, 0, npe, pWrk, pSync);
		}

		if (me == 0) {
			unsigned int nsec = ctimer_nsec(tsum / (npe * NLOOP));
			host_printf("%5d %7u\n", npe, nsec);
		}
	}

	shmem_finalize();

	return 0;
}