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/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include <stdio.h>
#include "mpitest.h"
/*
static char MTEST_Descrip[] = "A simple test of Comm_spawn, followed by intercomm merge";
*/
int main(int argc, char *argv[])
{
int errs = 0, err;
int rank, size, rsize, i;
int np = 2;
int errcodes[2];
MPI_Comm parentcomm, intercomm, intracomm, intracomm2, intracomm3;
int isChild = 0;
MPI_Status status;
int can_spawn;
MTest_Init(&argc, &argv);
errs += MTestSpawnPossible(&can_spawn);
if (can_spawn) {
MPI_Comm_get_parent(&parentcomm);
if (parentcomm == MPI_COMM_NULL) {
/* Create 2 more processes */
MPI_Comm_spawn((char *) "./spawnintra", MPI_ARGV_NULL, np,
MPI_INFO_NULL, 0, MPI_COMM_WORLD, &intercomm, errcodes);
} else
intercomm = parentcomm;
/* We now have a valid intercomm */
MPI_Comm_remote_size(intercomm, &rsize);
MPI_Comm_size(intercomm, &size);
MPI_Comm_rank(intercomm, &rank);
if (parentcomm == MPI_COMM_NULL) {
/* Parent */
if (rsize != np) {
errs++;
printf("Did not create %d processes (got %d)\n", np, rsize);
}
if (rank == 0) {
for (i = 0; i < rsize; i++) {
MPI_Send(&i, 1, MPI_INT, i, 0, intercomm);
}
}
} else {
/* Child */
isChild = 1;
if (size != np) {
errs++;
printf("(Child) Did not create %d processes (got %d)\n", np, size);
}
MPI_Recv(&i, 1, MPI_INT, 0, 0, intercomm, &status);
if (i != rank) {
errs++;
printf("Unexpected rank on child %d (%d)\n", rank, i);
}
}
/* At this point, try to form the intracommunicator */
MPI_Intercomm_merge(intercomm, isChild, &intracomm);
/* Check on the intra comm */
{
int icsize, icrank, wrank;
MPI_Comm_size(intracomm, &icsize);
MPI_Comm_rank(intracomm, &icrank);
MPI_Comm_rank(MPI_COMM_WORLD, &wrank);
if (icsize != rsize + size) {
errs++;
printf("Intracomm rank %d thinks size is %d, not %d\n",
icrank, icsize, rsize + size);
}
/* Make sure that the processes are ordered correctly */
if (isChild) {
int psize;
MPI_Comm_remote_size(parentcomm, &psize);
if (icrank != psize + wrank) {
errs++;
printf("Intracomm rank %d (from child) should have rank %d\n",
icrank, psize + wrank);
}
} else {
if (icrank != wrank) {
errs++;
printf("Intracomm rank %d (from parent) should have rank %d\n", icrank, wrank);
}
}
}
/* At this point, try to form the intracommunicator, with the other
* processes first */
MPI_Intercomm_merge(intercomm, !isChild, &intracomm2);
/* Check on the intra comm */
{
int icsize, icrank, wrank;
MPI_Comm_size(intracomm2, &icsize);
MPI_Comm_rank(intracomm2, &icrank);
MPI_Comm_rank(MPI_COMM_WORLD, &wrank);
if (icsize != rsize + size) {
errs++;
printf("(2)Intracomm rank %d thinks size is %d, not %d\n",
icrank, icsize, rsize + size);
}
/* Make sure that the processes are ordered correctly */
if (isChild) {
if (icrank != wrank) {
errs++;
printf("(2)Intracomm rank %d (from child) should have rank %d\n",
icrank, wrank);
}
} else {
int csize;
MPI_Comm_remote_size(intercomm, &csize);
if (icrank != wrank + csize) {
errs++;
printf("(2)Intracomm rank %d (from parent) should have rank %d\n",
icrank, wrank + csize);
}
}
}
/* At this point, try to form the intracommunicator, with an
* arbitrary choice for the first group of processes */
MPI_Intercomm_merge(intercomm, 0, &intracomm3);
/* Check on the intra comm */
{
int icsize, icrank, wrank;
MPI_Comm_size(intracomm3, &icsize);
MPI_Comm_rank(intracomm3, &icrank);
MPI_Comm_rank(MPI_COMM_WORLD, &wrank);
if (icsize != rsize + size) {
errs++;
printf("(3)Intracomm rank %d thinks size is %d, not %d\n",
icrank, icsize, rsize + size);
}
/* Eventually, we should test that the processes are ordered
* correctly, by groups (must be one of the two cases above) */
}
/* Update error count */
if (isChild) {
/* Send the errs back to the parent process */
MPI_Ssend(&errs, 1, MPI_INT, 0, 1, intercomm);
} else {
if (rank == 0) {
/* We could use intercomm reduce to get the errors from the
* children, but we'll use a simpler loop to make sure that
* we get valid data */
for (i = 0; i < rsize; i++) {
MPI_Recv(&err, 1, MPI_INT, i, 1, intercomm, MPI_STATUS_IGNORE);
errs += err;
}
}
}
/* It isn't necessary to free the intracomms, but it should not hurt */
MPI_Comm_free(&intracomm);
MPI_Comm_free(&intracomm2);
MPI_Comm_free(&intracomm3);
/* It isn't necessary to free the intercomm, but it should not hurt */
MPI_Comm_free(&intercomm);
/* Note that the MTest_Finalize get errs only over COMM_WORLD */
/* Note also that both the parent and child will generate "No Errors"
* if both call MTest_Finalize */
if (parentcomm == MPI_COMM_NULL) {
MTest_Finalize(errs);
} else {
MPI_Finalize();
}
} else {
MTest_Finalize(errs);
}
return MTestReturnValue(errs);
}
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