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/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
/* tests whether atomicity semantics are satisfied for overlapping accesses
in atomic mode. The probability of detecting errors is higher if you run
it on 8 or more processes. */
/* The file name is taken as a command-line argument. */
static void handle_error(int errcode, const char *str)
{
char msg[MPI_MAX_ERROR_STRING];
int resultlen;
MPI_Error_string(errcode, msg, &resultlen);
fprintf(stderr, "%s: %s\n", str, msg);
MPI_Abort(MPI_COMM_WORLD, 1);
}
#define MPI_CHECK(fn) { int errcode; errcode = (fn); if (errcode != MPI_SUCCESS) handle_error(errcode, #fn); }
#define BUFSIZE 10000 /* no. of integers */
#define VERBOSE 0
int main(int argc, char **argv)
{
int *writebuf, *readbuf, i, mynod, nprocs, len, err;
char *filename;
int errs = 0, toterrs;
MPI_Datatype newtype;
MPI_File fh;
MPI_Status status;
MPI_Info info;
MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &mynod);
MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
/* process 0 takes the file name as a command-line argument and
broadcasts it to other processes */
if (!mynod) {
i = 1;
while ((i < argc) && strcmp("-fname", *argv)) {
i++;
argv++;
}
if (i >= argc) {
fprintf(stderr, "\n*# Usage: coll_test -fname filename\n\n");
MPI_Abort(MPI_COMM_WORLD, 1);
}
argv++;
len = strlen(*argv);
filename = (char *) malloc(len + 1);
strcpy(filename, *argv);
MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD);
MPI_Bcast(filename, len + 1, MPI_CHAR, 0, MPI_COMM_WORLD);
} else {
MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD);
filename = (char *) malloc(len + 1);
MPI_Bcast(filename, len + 1, MPI_CHAR, 0, MPI_COMM_WORLD);
}
writebuf = (int *) malloc(BUFSIZE * sizeof(int));
readbuf = (int *) malloc(BUFSIZE * sizeof(int));
/* test atomicity of contiguous accesses */
/* initialize file to all zeros */
if (!mynod) {
/* ignore error: file may or may not exist */
MPI_File_delete(filename, MPI_INFO_NULL);
MPI_CHECK(MPI_File_open(MPI_COMM_SELF, filename,
MPI_MODE_CREATE | MPI_MODE_RDWR, MPI_INFO_NULL, &fh));
for (i = 0; i < BUFSIZE; i++)
writebuf[i] = 0;
MPI_CHECK(MPI_File_write(fh, writebuf, BUFSIZE, MPI_INT, &status));
MPI_CHECK(MPI_File_close(&fh));
#if VERBOSE
fprintf(stderr, "\ntesting contiguous accesses\n");
#endif
}
MPI_Barrier(MPI_COMM_WORLD);
for (i = 0; i < BUFSIZE; i++)
writebuf[i] = 10;
for (i = 0; i < BUFSIZE; i++)
readbuf[i] = 20;
MPI_CHECK(MPI_File_open(MPI_COMM_WORLD, filename,
MPI_MODE_CREATE | MPI_MODE_RDWR, MPI_INFO_NULL, &fh));
/* set atomicity to true */
err = MPI_File_set_atomicity(fh, 1);
if (err != MPI_SUCCESS) {
fprintf(stderr, "Atomic mode not supported on this file system.\n");
fflush(stderr);
errs++;
goto fn_exit;
}
MPI_Barrier(MPI_COMM_WORLD);
/* process 0 writes and others concurrently read. In atomic mode,
the data read must be either all old values or all new values; nothing
in between. */
if (!mynod) {
MPI_CHECK(MPI_File_write(fh, writebuf, BUFSIZE, MPI_INT, &status));
} else {
err = MPI_File_read(fh, readbuf, BUFSIZE, MPI_INT, &status);
if (err == MPI_SUCCESS) {
if (readbuf[0] == 0) { /* the rest must also be 0 */
for (i = 1; i < BUFSIZE; i++)
if (readbuf[i] != 0) {
errs++;
fprintf(stderr, "Process %d: readbuf[%d] is %d, should be 0\n", mynod, i,
readbuf[i]);
goto fn_exit;
}
} else if (readbuf[0] == 10) { /* the rest must also be 10 */
for (i = 1; i < BUFSIZE; i++)
if (readbuf[i] != 10) {
errs++;
fprintf(stderr, "Process %d: readbuf[%d] is %d, should be 10\n", mynod, i,
readbuf[i]);
goto fn_exit;
}
} else {
errs++;
fprintf(stderr, "Process %d: readbuf[0] is %d, should be either 0 or 10\n", mynod,
readbuf[0]);
}
}
}
MPI_CHECK(MPI_File_close(&fh));
MPI_Barrier(MPI_COMM_WORLD);
/* repeat the same test with a noncontiguous filetype */
MPI_Type_vector(BUFSIZE, 1, 2, MPI_INT, &newtype);
MPI_Type_commit(&newtype);
MPI_Info_create(&info);
/* I am setting these info values for testing purposes only. It is
* better to use the default values in practice. */
MPI_Info_set(info, "ind_rd_buffer_size", "1209");
MPI_Info_set(info, "ind_wr_buffer_size", "1107");
if (!mynod) {
MPI_CHECK(MPI_File_delete(filename, MPI_INFO_NULL));
MPI_CHECK(MPI_File_open(MPI_COMM_SELF, filename,
MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh));
for (i = 0; i < BUFSIZE; i++)
writebuf[i] = 0;
MPI_CHECK(MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", info));
MPI_CHECK(MPI_File_write(fh, writebuf, BUFSIZE, MPI_INT, &status));
MPI_File_close(&fh);
#if VERBOSE
fprintf(stderr, "\ntesting noncontiguous accesses\n");
#endif
}
MPI_Barrier(MPI_COMM_WORLD);
for (i = 0; i < BUFSIZE; i++)
writebuf[i] = 10;
for (i = 0; i < BUFSIZE; i++)
readbuf[i] = 20;
MPI_CHECK(MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh));
MPI_CHECK(MPI_File_set_atomicity(fh, 1));
MPI_CHECK(MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", info));
MPI_Barrier(MPI_COMM_WORLD);
if (!mynod) {
MPI_CHECK(MPI_File_write(fh, writebuf, BUFSIZE, MPI_INT, &status));
} else {
err = MPI_File_read(fh, readbuf, BUFSIZE, MPI_INT, &status);
if (err == MPI_SUCCESS) {
if (readbuf[0] == 0) {
for (i = 1; i < BUFSIZE; i++)
if (readbuf[i] != 0) {
errs++;
fprintf(stderr, "Process %d: readbuf[%d] is %d, should be 0\n", mynod, i,
readbuf[i]);
goto fn_exit;
}
} else if (readbuf[0] == 10) {
for (i = 1; i < BUFSIZE; i++)
if (readbuf[i] != 10) {
errs++;
fprintf(stderr, "Process %d: readbuf[%d] is %d, should be 10\n", mynod, i,
readbuf[i]);
goto fn_exit;
}
} else {
errs++;
fprintf(stderr, "Process %d: readbuf[0] is %d, should be either 0 or 10\n", mynod,
readbuf[0]);
}
}
}
MPI_Type_free(&newtype);
MPI_Info_free(&info);
fn_exit:
MPI_File_close(&fh);
MPI_Barrier(MPI_COMM_WORLD);
MPI_Allreduce(&errs, &toterrs, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD);
if (mynod == 0) {
if (toterrs > 0) {
fprintf(stderr, "Found %d errors\n", toterrs);
} else {
fprintf(stdout, " No Errors\n");
}
}
free(writebuf);
free(readbuf);
free(filename);
MPI_Finalize();
return 0;
}
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