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openmpi/ompi/mca/coll/basic/coll_basic_allgather.c
Jeff Squyres 5dca18f903 First cut of handling MPI_IN_PLACE:
- added relevant logic for everything except
  mca_coll_basic_reduce_log_intra() -- need some help from George /
  Edgar on this one...
- replaced ompi_ddt_sndrcv() with ompi_ddt_copy_content_same_ddt()
  where relevant
- removed some "if (size > 1)" conditionals, because the self coll
  module will always be chosen for collectives where size==1

Waiting for BA's tests to check the validity of this IN_PLACE stuff.
We'll see how it goes!

This commit was SVN r7351.
2005-09-13 20:06:54 +00:00

244 строки
7.4 KiB
C

/*
* Copyright (c) 2004-2005 The Trustees of Indiana University.
* All rights reserved.
* Copyright (c) 2004-2005 The Trustees of the University of Tennessee.
* All rights reserved.
* Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
* University of Stuttgart. All rights reserved.
* Copyright (c) 2004-2005 The Regents of the University of California.
* All rights reserved.
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
#include "ompi_config.h"
#include "coll_basic.h"
#include "mpi.h"
#include "ompi/include/constants.h"
#include "ompi/datatype/datatype.h"
#include "ompi/mca/coll/coll.h"
#include "ompi/mca/pml/pml.h"
#include "ompi/mca/coll/base/coll_tags.h"
#include "coll_basic.h"
/*
* allgather_intra
*
* Function: - allgather using other MPI collections
* Accepts: - same as MPI_Allgather()
* Returns: - MPI_SUCCESS or error code
*/
int
mca_coll_basic_allgather_intra(void *sbuf, int scount,
struct ompi_datatype_t *sdtype, void *rbuf,
int rcount, struct ompi_datatype_t *rdtype,
struct ompi_communicator_t *comm)
{
int err;
char *inplace_temp = NULL;
long true_lb, true_extent, lb, extent;
/* Handle MPI_IN_PLACE (see explanantion in reduce.c for how to
allocate temp buffer) */
if (MPI_IN_PLACE == sbuf) {
sbuf = rbuf;
sdtype = rdtype;
scount = rcount;
ompi_ddt_get_extent(rdtype, &lb, &extent);
ompi_ddt_get_true_extent(rdtype, &true_lb, &true_extent);
inplace_temp = malloc(true_extent + (rcount - 1) * extent);
if (NULL == inplace_temp) {
return OMPI_ERR_OUT_OF_RESOURCE;
}
rbuf = inplace_temp - lb;
}
/* Gather and broadcast. */
err = comm->c_coll.coll_gather(sbuf, scount, sdtype, rbuf, rcount,
rdtype, 0, comm);
if (MPI_SUCCESS != err) {
return err;
}
err = comm->c_coll.coll_bcast(rbuf, rcount * ompi_comm_size(comm),
rdtype, 0, comm);
if (MPI_SUCCESS != err) {
return err;
}
/* If we're IN_PLACE, copy back out (sendcount and sendtype are
ignored) */
if (NULL != inplace_temp) {
ompi_ddt_copy_content_same_ddt(rdtype, rcount, rbuf, sbuf);
free(inplace_temp);
}
/* All done */
return MPI_SUCCESS;
}
/*
* allgather_inter
*
* Function: - allgather using other MPI collections
* Accepts: - same as MPI_Allgather()
* Returns: - MPI_SUCCESS or error code
*/
int
mca_coll_basic_allgather_inter(void *sbuf, int scount,
struct ompi_datatype_t *sdtype,
void *rbuf, int rcount,
struct ompi_datatype_t *rdtype,
struct ompi_communicator_t *comm)
{
int rank;
int root = 0;
int size, rsize;
int err;
int i;
char *tmpbuf = NULL, *ptmp;
long rlb, slb, rextent, sextent;
long incr;
ompi_request_t *req;
ompi_request_t **reqs = comm->c_coll_basic_data->mccb_reqs;
rank = ompi_comm_rank(comm);
size = ompi_comm_size(comm);
rsize = ompi_comm_remote_size(comm);
/* Algorithm:
* - a gather to the root in remote group (simultaniously executed,
* thats why we cannot use coll_gather).
* - exchange the temp-results between two roots
* - inter-bcast (again simultanious).
*/
/* Step one: gather operations: */
if (rank != root) {
/* send your data to root */
err = MCA_PML_CALL(send(sbuf, scount, sdtype, root,
MCA_COLL_BASE_TAG_ALLGATHER,
MCA_PML_BASE_SEND_STANDARD, comm));
if (OMPI_SUCCESS != err) {
return err;
}
} else {
/* receive a msg. from all other procs. */
err = ompi_ddt_get_extent(rdtype, &rlb, &rextent);
if (OMPI_SUCCESS != err) {
return err;
}
err = ompi_ddt_get_extent(sdtype, &slb, &sextent);
if (OMPI_SUCCESS != err) {
return err;
}
/* Do a send-recv between the two root procs. to avoid deadlock */
err = MCA_PML_CALL(isend(sbuf, scount, sdtype, 0,
MCA_COLL_BASE_TAG_ALLGATHER,
MCA_PML_BASE_SEND_STANDARD,
comm, &reqs[rsize]));
if (OMPI_SUCCESS != err) {
return err;
}
err = MCA_PML_CALL(irecv(rbuf, rcount, rdtype, 0,
MCA_COLL_BASE_TAG_ALLGATHER, comm,
&reqs[0]));
if (OMPI_SUCCESS != err) {
return err;
}
incr = rextent * rcount;
ptmp = (char *) rbuf + incr;
for (i = 1; i < rsize; ++i, ptmp += incr) {
err = MCA_PML_CALL(irecv(ptmp, rcount, rdtype, i,
MCA_COLL_BASE_TAG_ALLGATHER,
comm, &reqs[i]));
if (MPI_SUCCESS != err) {
return err;
}
}
err = ompi_request_wait_all(rsize + 1, reqs, MPI_STATUSES_IGNORE);
if (OMPI_SUCCESS != err) {
return err;
}
/* Step 2: exchange the resuts between the root processes */
tmpbuf = (char *) malloc(scount * size * sextent);
if (NULL == tmpbuf) {
return err;
}
err = MCA_PML_CALL(isend(rbuf, rsize * rcount, rdtype, 0,
MCA_COLL_BASE_TAG_ALLGATHER,
MCA_PML_BASE_SEND_STANDARD, comm, &req));
if (OMPI_SUCCESS != err) {
goto exit;
}
err = MCA_PML_CALL(recv(tmpbuf, size * scount, sdtype, 0,
MCA_COLL_BASE_TAG_ALLGATHER, comm,
MPI_STATUS_IGNORE));
if (OMPI_SUCCESS != err) {
goto exit;
}
err = ompi_request_wait_all(1, &req, MPI_STATUS_IGNORE);
if (OMPI_SUCCESS != err) {
goto exit;
}
}
/* Step 3: bcast the data to the remote group. This
* happens in both groups simultaniously, thus we can
* not use coll_bcast (this would deadlock).
*/
if (rank != root) {
/* post the recv */
err = MCA_PML_CALL(recv(rbuf, size * rcount, rdtype, 0,
MCA_COLL_BASE_TAG_ALLGATHER, comm,
MPI_STATUS_IGNORE));
if (OMPI_SUCCESS != err) {
goto exit;
}
} else {
/* Send the data to every other process in the remote group
* except to rank zero. which has it already. */
for (i = 1; i < rsize; i++) {
err = MCA_PML_CALL(isend(tmpbuf, size * scount, sdtype, i,
MCA_COLL_BASE_TAG_ALLGATHER,
MCA_PML_BASE_SEND_STANDARD,
comm, &reqs[i - 1]));
if (OMPI_SUCCESS != err) {
goto exit;
}
}
err = ompi_request_wait_all(rsize - 1, reqs, MPI_STATUSES_IGNORE);
if (OMPI_SUCCESS != err) {
goto exit;
}
}
exit:
if (NULL != tmpbuf) {
free(tmpbuf);
}
return err;
}