One-sided communication in RCCE

rcce_put.c

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include "RCCE.h"
#include "RCCE_lib.h"

#define PRINT(...) { printf(__VA_ARGS__); fflush(stdout); }

int RCCE_APP(int argc, char *argv[])
{
	int ID, nprocs, next, prev;
	int buf[8];
	t_vcharp p;

	dup2(STDOUT_FILENO, STDERR_FILENO);

	RCCE_init(&argc, &argv);

	ID = RCCE_ue();
	nprocs = RCCE_num_ues();
	next = (ID + 1) % nprocs;
	prev = (ID - 1 + nprocs) % nprocs;

	p = RCCE_malloc(RCCE_LINE_SIZE);
	
	// RCCE_put() and RCCE_get() copy data in cache line chunks
	buf[0] = 0;
	RCCE_put(p, (t_vcharp)buf, sizeof(buf), ID);
	
	RCCE_barrier(&RCCE_COMM_WORLD);

	buf[0] = ID;
	RCCE_put(p, (t_vcharp)buf, sizeof(buf), next);
	
	RCCE_barrier(&RCCE_COMM_WORLD);
	
	RCCE_get((t_vcharp)buf, p, sizeof(buf), ID);
	assert(buf[0] == prev);
	PRINT("Core %d reads a value of %d\n", ID, buf[0]);
	
	// Alternatively, with explicit MPBT cache line invalidations 
	//RC_cache_invalidate();
	//assert(*(int *)p == prev);
	//PRINT("Core %d reads a value of %d\n", ID, *(int *)p);

	RCCE_finalize();

	return 0;
}