pgon.c

Parallel programming／Lou Baker, Bradley J.Smith ．—New York：McGraw-Hill Book Co.

/* PSPH - Parallel SPH program
 * Brad Smith and Lou Baker, Dagonet Software
 */
static char sccs_id[] = "@(#) /home2/bsmith/src/psph/SCCS/s.pgon.c 1.4 94/03/15 (PSPH)";

/* MPI Implementation for Intel Paragon */

#include "all.h"

/* Some compilers require at least one external reference */
extern int NProc;

#ifdef PGON_MSG
static pid_t *pids; /* Task id array */
static int PGON_nproc,PGON_proc;
static long p_type;

#define PGON_PTYPE p_type


/* Initialize n copies of the named process */
int
PGON_Init(int n, int argc, char **argv)
{
 int i;
 int num;

 if((num=numnodes()) > 1)
	PGON_nproc = num; /* Already initialized */
 else
 	PGON_nproc = n;

 if(n<=1 && num == 1)
	{
	PGON_proc = 0;
	return(MPI_SUCCESS);
	}

 if(num <= 1 && n > 1)
	{
#ifdef NOTDEF /* Doesn't work with IP switch */
 	/* Initialize partition */
 	if(nx_initve(NULL, (long)n, NULL, &argc, argv) <= 0)
		return(MPI_FAILURE);

 	/* Fork them */
 	pids = New(sizeof(pid_t) * n);
 	if((i=nx_nfork(NULL, -1, 0, pids)) < 0)
		return(MPI_FAILURE);

 	if(i > 0) /* Controlling process stays out of things */
		{
		nx_waitall();
		Exit(0);
		}
#else
	printf("Specify number of processes with '-sz' option as in: psph -plk -sz 4\n");
	return(MPI_FAILURE);
#endif
	}

 PGON_proc = mynode();
#ifdef OLD
 setptype(PGON_PTYPE);
#endif
 p_type = myptype();

 return(MPI_SUCCESS);
} 

int
PGON_Rank()
{
 return PGON_proc;
}

int
PGON_Nproc()
{
 return(PGON_nproc);
}

void
PGON_Abort(int errcode)
{
 int i;

 /* Kill everyone */
 kill(0, SIGTERM);

 /* Kill ourselves */
 Exit(0);
}

/* Overkill - but the paragon wants longs, not ints */
static long *Ldest;

/* Now capable of doing a multisend */
int
PGON_Send(void *buf, int count, MPI_Datatype data_type, int *dest, int ndest, int tag)
{
 int i;
 
 if(!Ldest)
	Ldest = (long *) New(sizeof(long)*PGON_nproc);

 /* Copy to long array (probably overkill, but we want portability) */
 for(i=0; i<ndest; i++)
	Ldest[i] = (long) dest[i];

 /* Begin multi-send */
 gsendx((long) tag, buf, (long) (count * _MPI_SizeDataType(data_type)), Ldest, (long)ndest);

 return(MPI_SUCCESS);
}

int
PGON_Receive(void *buf, int count, int data_type, int source,
	int tag, MPI_Status *status)
{
 long info[8];

 if(source >= PGON_nproc || source < MPI_ANY_SOURCE)
	{
	UserMessage("PVM_Receive: Attempt to receive on bad source=%d\n", source);
	return(MPI_FAILURE);
	}

 /* Blocking extended receive */
 crecvx((long) tag, buf, (long) (count * _MPI_SizeDataType(data_type)), (long)source, 
	(long) PGON_PTYPE, info);

 /* Grab message stats */
 status->count = (int) (info[1] / _MPI_SizeDataType(data_type));
 status->source = (int) info[2];
 status->tag = (int)info[0];

 return(MPI_SUCCESS);
}

int
PGON_Isend(void *buf, int count, MPI_Datatype data_type, int dest,
	int tag, MPI_Comm_request *request)
{
 
 request->msgid = isend(tag, buf, (count * _MPI_SizeDataType(data_type)), dest, PGON_PTYPE);
 request->is_send = TRUE;
 request->status.tag = tag;
 request->status.source = dest;
 request->status.count = count;
 return(MPI_SUCCESS);
}

int
PGON_Irecv(void *buf, int count, MPI_Datatype data_type, int source,
	int tag, MPI_Comm_request *request)
{
 /* NOT IMPLEMENTED */
 
 return(MPI_FAILURE);
}

int
PGON_Wait(MPI_Comm_request *request, MPI_Status *status)
{
 msgwait(request->msgid);
 return(MPI_SUCCESS);
}

int
PGON_Test(MPI_Comm_request *request, MPI_Status *status)
{
 return(msgdone(request->msgid));
}

int
PGON_Probe(int source, int tag, int *flag, MPI_Status *status)
{
 long info[8];

 if(!iprobex((long) tag,(long)source, (long) -1, info))
	{
	*flag = FALSE;
	return(MPI_SUCCESS);
	}
 /* Count is inaccurate (in bytes) - but that's OK */
 status->count = (int) info[1];
 status->source = (int) info[2];
 status->tag = (int) info[0];
 *flag = TRUE;
 return(MPI_SUCCESS);
}


#endif /* PGON_MSG */