+++ /dev/null
-/* ictest3.c
- This is like ictest2.c, but it creates communictors that are valid only
- at the "leaders"; other members of the local communicator are NOT
- in the remote communicator. A peer communicator is constructed that
- contains both leaders.
-
-
- */
-#include "mpi.h"
-#include <stdio.h>
-#include "test.h"
-
-/* #define DEBUG */
-
-int verbose = 0;
-
-int main( int argc, char **argv )
-{
- int size, rank, key, lrank, rsize, result;
- MPI_Comm myFirstComm;
- MPI_Comm mySecondComm;
- MPI_Comm newComm, peerComm;
- MPI_Group rgroup, lgroup, igroup;
- int errors = 0, sum_errors;
- int flag;
- MPI_Status status;
-
- /* Initialization */
- MPI_Init ( &argc, &argv );
- MPI_Comm_rank ( MPI_COMM_WORLD, &rank);
- MPI_Comm_size ( MPI_COMM_WORLD, &size);
-
- /* Only works for 2 or more processes */
- /*
- We create an even and odd communicator, then create an
- intercommunicator out of them. For this purpose, we use a
- "peer" communicator valid only at one member of each of the odd and
- even communicators.
- */
- if (size >= 2) {
- MPI_Comm merge1, merge2, merge3, merge4;
-
- /* Generate membership key in the range [0,1] */
- key = rank % 2;
- /* Create the even communicator and odd communicators */
- MPI_Comm_split ( MPI_COMM_WORLD, key, rank, &newComm );
-
- MPI_Comm_test_inter( newComm, &flag );
- if (flag) {
- errors++;
- printf( "[%d] got test_inter gave true for intra comm\n", rank );
- }
-
- /* Create the "peer" communicator */
- key = 0;
- if (rank < 2) key = 1;
- MPI_Comm_split( MPI_COMM_WORLD, key, rank, &peerComm );
- if (key == 0) {
- MPI_Comm_free( &peerComm );
- }
-#ifdef DEBUG
- else {
- MPI_Comm_rank( peerComm, &lrank );
- printf( "[%d] lrank in peerComm is %d (color = %d, key=%d)\n",
- rank, lrank, key, rank );
- }
-#endif
-
- /* Check that the leader is who we think he is */
- MPI_Comm_rank( newComm, &lrank );
- /* printf( "[%d] local rank is %d\n", rank, lrank );
- fflush(stdout); */
- /* Perform the intercomm create and test it */
- /* Local leader is always the one at rank 0. */
- /* If even, the remote leader is rank 1, if odd, the remote leader
- is rank 0 in the peercomm */
- MPI_Intercomm_create (newComm, 0, peerComm, !(rank % 2), 1, &myFirstComm );
-#ifdef DEBUG
- printf( "[%d] through intercom create\n", rank );
- fflush( stdout );
- MPI_Barrier( MPI_COMM_WORLD );
- printf( "[%d] through barrier at end of intercom create\n", rank );
-#endif
- MPI_Comm_test_inter( myFirstComm, &flag );
- if (!flag) {
- errors++;
- printf( "[%d] got test_inter gave false for inter comm\n", rank );
- }
-
- /* Try to dup this communicator */
- MPI_Comm_dup ( myFirstComm, &mySecondComm );
- MPI_Comm_test_inter( mySecondComm, &flag );
- if (!flag) {
- errors++;
- printf( "[%d] got test_inter gave false for dup of inter comm\n",
- rank );
- }
-
-#ifdef DEBUG
- printf( "[%d] through comm dup\n", rank );
- fflush( stdout );
- MPI_Barrier( MPI_COMM_WORLD );
- printf( "[%d] through barrier at end of comm dup\n", rank );
-#endif
-
- /* Each member shares data with his "partner". */
- MPI_Comm_rank( mySecondComm, &lrank );
- MPI_Comm_remote_size( mySecondComm, &rsize );
-
-#ifdef DEBUG
- printf( "[%d] lrank in secondcomm is %d and remote size is %d\n",
- rank, lrank, rsize );
- fflush( stdout );
-#endif
-
- /* Check that the remote group is what we think */
- MPI_Comm_remote_group( mySecondComm, &rgroup );
- MPI_Comm_group( newComm, &lgroup );
- MPI_Group_intersection( rgroup, lgroup, &igroup );
- MPI_Group_compare( igroup, MPI_GROUP_EMPTY, &flag );
- if (flag != MPI_IDENT) {
- errors++;
- printf( "[%d] intersection of remote and local group is not empty\n",
- rank );
- }
- MPI_Group_free( &rgroup );
- MPI_Group_free( &lgroup );
- MPI_Group_free( &igroup );
-
- /* Send key * size + rank in communicator */
- if (lrank < rsize) {
- int myval, hisval;
- key = rank % 2;
- myval = key * size + lrank;
- hisval = -1;
-#ifdef DEBUG
- printf( "[%d] exchanging %d with %d in intercomm\n",
- rank, myval, lrank );
- fflush( stdout );
-#endif
- MPI_Sendrecv (&myval, 1, MPI_INT, lrank, 0,
- &hisval, 1, MPI_INT, lrank, 0, mySecondComm, &status);
- if (hisval != (lrank + (!key)*size)) {
- printf( "[%d] expected %d but got %d\n", rank, lrank + (!key)*size,
- hisval );
- errors++;
- }
- }
-
- if (errors)
- printf("[%d] Failed!\n",rank);
-
- /* Key is 1 for oddComm, 0 for evenComm (note both contain 0 in WORLD) */
-#ifdef DEBUG
- printf( "[%d] starting intercom merge\n", rank );
- fflush( stdout );
-#endif
- MPI_Intercomm_merge ( mySecondComm, key, &merge1 );
- MPI_Intercomm_merge ( mySecondComm, (key+1)%2, &merge2 );
- MPI_Intercomm_merge ( mySecondComm, 0, &merge3 );
- MPI_Intercomm_merge ( mySecondComm, 1, &merge4 );
-
- MPI_Comm_compare( merge1, MPI_COMM_WORLD, &result );
- if (result != MPI_SIMILAR && size > 2) {
- printf( "[%d] comparision with merge1 failed\n", rank );
- errors++;
- }
-
- /* Free communicators */
- if (verbose) printf( "about to free communicators\n" );
- MPI_Comm_free( &newComm );
- if (peerComm != MPI_COMM_NULL) MPI_Comm_free( &peerComm );
- MPI_Comm_free( &myFirstComm );
- MPI_Comm_free( &mySecondComm );
- MPI_Comm_free( &merge1 );
- MPI_Comm_free( &merge2 );
- MPI_Comm_free( &merge3 );
- MPI_Comm_free( &merge4 );
- }
- else
- printf("[%d] Failed - at least 2 nodes must be used\n",rank);
-
- MPI_Barrier( MPI_COMM_WORLD );
- MPI_Allreduce( &errors, &sum_errors, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD );
- if (sum_errors > 0) {
- printf( "%d errors on process %d\n", errors, rank );
- }
- else if (rank == 0) {
- printf( " No Errors\n" );
- }
- /* Finalize and end! */
-
- MPI_Finalize();
- return 0;
-}
