int MPIR_Barrier_intra( MPID_Comm *comm_ptr, MPIR_Errflag_t *errflag )
{
int size, rank, src, dst, mask, mpi_errno=MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
/* Only one collective operation per communicator can be active at any
time */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
size = comm_ptr->local_size;
/* Trivial barriers return immediately */
if (size == 1) goto fn_exit;
if (MPIR_CVAR_ENABLE_SMP_COLLECTIVES && MPIR_CVAR_ENABLE_SMP_BARRIER &&
MPIR_Comm_is_node_aware(comm_ptr)) {
mpi_errno = barrier_smp_intra(comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
goto fn_exit;
}
rank = comm_ptr->rank;
mask = 0x1;
while (mask < size) {
dst = (rank + mask) % size;
src = (rank - mask + size) % size;
mpi_errno = MPIC_Sendrecv(NULL, 0, MPI_BYTE, dst,
MPIR_BARRIER_TAG, NULL, 0, MPI_BYTE,
src, MPIR_BARRIER_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
mask <<= 1;
}
fn_exit:
MPIDU_ERR_CHECK_MULTIPLE_THREADS_EXIT( comm_ptr );
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag != MPIR_ERR_NONE)
MPIR_ERR_SET(mpi_errno, *errflag, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Get_intercomm_contextid(MPIR_Comm * comm_ptr, MPIR_Context_id_t * context_id,
MPIR_Context_id_t * recvcontext_id)
{
MPIR_Context_id_t mycontext_id, remote_context_id;
int mpi_errno = MPI_SUCCESS;
int tag = 31567; /* FIXME - we need an internal tag or
* communication channel. Can we use a different
* context instead?. Or can we use the tag
* provided in the intercomm routine? (not on a dup,
* but in that case it can use the collective context) */
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPIR_GET_INTERCOMM_CONTEXTID);
MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPIR_GET_INTERCOMM_CONTEXTID);
if (!comm_ptr->local_comm) {
/* Manufacture the local communicator */
mpi_errno = MPII_Setup_intercomm_localcomm(comm_ptr);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
}
mpi_errno = MPIR_Get_contextid_sparse(comm_ptr->local_comm, &mycontext_id, FALSE);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
MPIR_Assert(mycontext_id != 0);
/* MPIC routine uses an internal context id. The local leads (process 0)
* exchange data */
remote_context_id = -1;
if (comm_ptr->rank == 0) {
mpi_errno = MPIC_Sendrecv(&mycontext_id, 1, MPIR_CONTEXT_ID_T_DATATYPE, 0, tag,
&remote_context_id, 1, MPIR_CONTEXT_ID_T_DATATYPE, 0, tag,
comm_ptr, MPI_STATUS_IGNORE, &errflag);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
}
/* Make sure that all of the local processes now have this
* id */
mpi_errno = MPID_Bcast(&remote_context_id, 1, MPIR_CONTEXT_ID_T_DATATYPE,
0, comm_ptr->local_comm, &errflag);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
MPIR_ERR_CHKANDJUMP(errflag, mpi_errno, MPI_ERR_OTHER, "**coll_fail");
/* The recvcontext_id must be the one that was allocated out of the local
* group, not the remote group. Otherwise we could end up posting two
* MPI_ANY_SOURCE,MPI_ANY_TAG recvs on the same context IDs even though we
* are attempting to post them for two separate communicators. */
*context_id = remote_context_id;
*recvcontext_id = mycontext_id;
fn_fail:
MPIR_FUNC_TERSE_EXIT(MPID_STATE_MPIR_GET_INTERCOMM_CONTEXTID);
return mpi_errno;
}
int MPIR_Intercomm_merge_impl(MPID_Comm *comm_ptr, int high, MPID_Comm **new_intracomm_ptr)
{
int mpi_errno = MPI_SUCCESS;
int local_high, remote_high, new_size;
MPIU_Context_id_t new_context_id;
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
MPID_MPI_STATE_DECL(MPID_STATE_MPIR_INTERCOMM_MERGE_IMPL);
MPID_MPI_FUNC_ENTER(MPID_STATE_MPIR_INTERCOMM_MERGE_IMPL);
/* Make sure that we have a local intercommunicator */
if (!comm_ptr->local_comm) {
/* Manufacture the local communicator */
mpi_errno = MPIR_Setup_intercomm_localcomm( comm_ptr );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
/* Find the "high" value of the other group of processes. This
will be used to determine which group is ordered first in
the generated communicator. high is logical */
local_high = high;
if (comm_ptr->rank == 0) {
/* This routine allows use to use the collective communication
context rather than the point-to-point context. */
mpi_errno = MPIC_Sendrecv( &local_high, 1, MPI_INT, 0, 0,
&remote_high, 1, MPI_INT, 0, 0, comm_ptr,
MPI_STATUS_IGNORE, &errflag );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* If local_high and remote_high are the same, then order is arbitrary.
we use the gpids of the rank 0 member of the local and remote
groups to choose an order in this case. */
if (local_high == remote_high) {
MPID_Gpid ingpid, outgpid;
mpi_errno = MPID_GPID_Get( comm_ptr, 0, &ingpid );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIC_Sendrecv( &ingpid, sizeof(MPID_Gpid), MPI_BYTE, 0, 1,
&outgpid, sizeof(MPID_Gpid), MPI_BYTE, 0, 1, comm_ptr,
MPI_STATUS_IGNORE, &errflag );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* Note that the gpids cannot be the same because we are
starting from a valid intercomm */
int rc = memcmp(&ingpid,&outgpid,sizeof(MPID_Gpid));
if(rc < 0)
local_high = 1;
else if(rc > 0)
local_high = 0;
else
{
/* req#3930: The merge algorithm will deadlock if the gpids are inadvertently the
same due to implementation bugs in the MPID_GPID_Get() function */
MPIU_Assert(rc != 0);
}
}
}
/*
All processes in the local group now need to get the
value of local_high, which may have changed if both groups
of processes had the same value for high
*/
mpi_errno = MPIR_Bcast_impl( &local_high, 1, MPI_INT, 0, comm_ptr->local_comm, &errflag );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIR_ERR_CHKANDJUMP(errflag, mpi_errno, MPI_ERR_OTHER, "**coll_fail");
mpi_errno = MPIR_Comm_create( new_intracomm_ptr );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
new_size = comm_ptr->local_size + comm_ptr->remote_size;
/* FIXME: For the intracomm, we need a consistent context id.
That means that one of the two groups needs to use
the recvcontext_id and the other must use the context_id */
if (local_high) {
(*new_intracomm_ptr)->context_id = comm_ptr->recvcontext_id + 2; /* See below */
}
else {
(*new_intracomm_ptr)->context_id = comm_ptr->context_id + 2; /* See below */
}
(*new_intracomm_ptr)->recvcontext_id = (*new_intracomm_ptr)->context_id;
(*new_intracomm_ptr)->remote_size = (*new_intracomm_ptr)->local_size = new_size;
(*new_intracomm_ptr)->rank = -1;
(*new_intracomm_ptr)->comm_kind = MPID_INTRACOMM;
/* Now we know which group comes first. Build the new mapping
from the existing comm */
mpi_errno = create_and_map(comm_ptr, local_high, (*new_intracomm_ptr));
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* We've setup a temporary context id, based on the context id
used by the intercomm. This allows us to perform the allreduce
operations within the context id algorithm, since we already
have a valid (almost - see comm_create_hook) communicator.
*/
mpi_errno = MPIR_Comm_commit((*new_intracomm_ptr));
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* printf( "About to get context id \n" ); fflush( stdout ); */
/* In the multi-threaded case, MPIR_Get_contextid_sparse assumes that the
calling routine already holds the single criticial section */
new_context_id = 0;
mpi_errno = MPIR_Get_contextid_sparse( (*new_intracomm_ptr), &new_context_id, FALSE );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIU_Assert(new_context_id != 0);
/* We release this communicator that was involved just to
* get valid context id and create true one
*/
mpi_errno = MPIR_Comm_release(*new_intracomm_ptr);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIR_Comm_create( new_intracomm_ptr );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
(*new_intracomm_ptr)->remote_size = (*new_intracomm_ptr)->local_size = new_size;
(*new_intracomm_ptr)->rank = -1;
(*new_intracomm_ptr)->comm_kind = MPID_INTRACOMM;
(*new_intracomm_ptr)->context_id = new_context_id;
(*new_intracomm_ptr)->recvcontext_id = new_context_id;
mpi_errno = create_and_map(comm_ptr, local_high, (*new_intracomm_ptr));
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIR_Comm_commit((*new_intracomm_ptr));
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
fn_exit:
MPID_MPI_FUNC_EXIT(MPID_STATE_MPIR_INTERCOMM_MERGE_IMPL);
return mpi_errno;
fn_fail:
goto fn_exit;
}
/* comm create impl for intercommunicators, assumes that the standard error
* checking has already taken place in the calling function */
PMPI_LOCAL int MPIR_Comm_create_inter(MPIR_Comm *comm_ptr, MPIR_Group *group_ptr,
MPIR_Comm **newcomm_ptr)
{
int mpi_errno = MPI_SUCCESS;
MPIR_Context_id_t new_context_id;
int *mapping = NULL;
int *remote_mapping = NULL;
MPIR_Comm *mapping_comm = NULL;
int remote_size = -1;
int rinfo[2];
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
MPIR_CHKLMEM_DECL(1);
MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPIR_COMM_CREATE_INTER);
MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPIR_COMM_CREATE_INTER);
MPIR_Assert(comm_ptr->comm_kind == MPIR_COMM_KIND__INTERCOMM);
/* Create a new communicator from the specified group members */
/* If there is a context id cache in oldcomm, use it here. Otherwise,
use the appropriate algorithm to get a new context id.
Creating the context id is collective over the *input* communicator,
so it must be created before we decide if this process is a
member of the group */
/* In the multi-threaded case, MPIR_Get_contextid_sparse assumes that the
calling routine already holds the single criticial section */
if (!comm_ptr->local_comm) {
MPII_Setup_intercomm_localcomm( comm_ptr );
}
mpi_errno = MPIR_Get_contextid_sparse( comm_ptr->local_comm, &new_context_id, FALSE );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIR_Assert(new_context_id != 0);
MPIR_Assert(new_context_id != comm_ptr->recvcontext_id);
mpi_errno = MPII_Comm_create_calculate_mapping(group_ptr, comm_ptr,
&mapping, &mapping_comm);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
*newcomm_ptr = NULL;
if (group_ptr->rank != MPI_UNDEFINED) {
/* Get the new communicator structure and context id */
mpi_errno = MPIR_Comm_create( newcomm_ptr );
if (mpi_errno) goto fn_fail;
(*newcomm_ptr)->recvcontext_id = new_context_id;
(*newcomm_ptr)->rank = group_ptr->rank;
(*newcomm_ptr)->comm_kind = comm_ptr->comm_kind;
/* Since the group has been provided, let the new communicator know
about the group */
(*newcomm_ptr)->local_comm = 0;
(*newcomm_ptr)->local_group = group_ptr;
MPIR_Group_add_ref( group_ptr );
(*newcomm_ptr)->local_size = group_ptr->size;
(*newcomm_ptr)->pof2 = MPL_pof2((*newcomm_ptr)->local_size);
(*newcomm_ptr)->remote_group = 0;
(*newcomm_ptr)->is_low_group = comm_ptr->is_low_group;
}
/* There is an additional step. We must communicate the
information on the local context id and the group members,
given by the ranks so that the remote process can construct the
appropriate network address mapping.
First we exchange group sizes and context ids. Then the ranks
in the remote group, from which the remote network address
mapping can be constructed. We need to use the "collective"
context in the original intercommunicator */
if (comm_ptr->rank == 0) {
int info[2];
info[0] = new_context_id;
info[1] = group_ptr->size;
mpi_errno = MPIC_Sendrecv(info, 2, MPI_INT, 0, 0,
rinfo, 2, MPI_INT, 0, 0,
comm_ptr, MPI_STATUS_IGNORE, &errflag );
if (mpi_errno) { MPIR_ERR_POP( mpi_errno ); }
if (*newcomm_ptr != NULL) {
(*newcomm_ptr)->context_id = rinfo[0];
}
remote_size = rinfo[1];
MPIR_CHKLMEM_MALLOC(remote_mapping,int*,
remote_size*sizeof(int),
mpi_errno,"remote_mapping",MPL_MEM_ADDRESS);
/* Populate and exchange the ranks */
mpi_errno = MPIC_Sendrecv( mapping, group_ptr->size, MPI_INT, 0, 0,
remote_mapping, remote_size, MPI_INT, 0, 0,
comm_ptr, MPI_STATUS_IGNORE, &errflag );
if (mpi_errno) { MPIR_ERR_POP( mpi_errno ); }
/* Broadcast to the other members of the local group */
mpi_errno = MPID_Bcast( rinfo, 2, MPI_INT, 0,
comm_ptr->local_comm, &errflag);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPID_Bcast( remote_mapping, remote_size, MPI_INT, 0,
comm_ptr->local_comm, &errflag);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIR_ERR_CHKANDJUMP(errflag, mpi_errno, MPI_ERR_OTHER, "**coll_fail");
}
int MPIR_Exscan (
const void *sendbuf,
void *recvbuf,
int count,
MPI_Datatype datatype,
MPI_Op op,
MPIR_Comm *comm_ptr,
MPIR_Errflag_t *errflag )
{
MPI_Status status;
int rank, comm_size;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
int mask, dst, is_commutative, flag;
MPI_Aint true_extent, true_lb, extent;
void *partial_scan, *tmp_buf;
MPIR_Op *op_ptr;
MPIR_CHKLMEM_DECL(2);
if (count == 0) return MPI_SUCCESS;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
/* set op_errno to 0. stored in perthread structure */
{
MPIR_Per_thread_t *per_thread = NULL;
int err = 0;
MPID_THREADPRIV_KEY_GET_ADDR(MPIR_ThreadInfo.isThreaded, MPIR_Per_thread_key,
MPIR_Per_thread, per_thread, &err);
MPIR_Assert(err == 0);
per_thread->op_errno = 0;
}
if (HANDLE_GET_KIND(op) == HANDLE_KIND_BUILTIN) {
is_commutative = 1;
}
else {
MPIR_Op_get_ptr(op, op_ptr);
if (op_ptr->kind == MPIR_OP_KIND__USER_NONCOMMUTE)
is_commutative = 0;
else
is_commutative = 1;
}
/* need to allocate temporary buffer to store partial scan*/
MPIR_Type_get_true_extent_impl(datatype, &true_lb, &true_extent);
MPID_Datatype_get_extent_macro( datatype, extent );
MPIR_CHKLMEM_MALLOC(partial_scan, void *, (count*(MPL_MAX(true_extent,extent))), mpi_errno, "partial_scan");
/* adjust for potential negative lower bound in datatype */
partial_scan = (void *)((char*)partial_scan - true_lb);
/* need to allocate temporary buffer to store incoming data*/
MPIR_CHKLMEM_MALLOC(tmp_buf, void *, (count*(MPL_MAX(true_extent,extent))), mpi_errno, "tmp_buf");
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - true_lb);
mpi_errno = MPIR_Localcopy((sendbuf == MPI_IN_PLACE ? (const void *)recvbuf : sendbuf), count, datatype,
partial_scan, count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
flag = 0;
mask = 0x1;
while (mask < comm_size) {
dst = rank ^ mask;
if (dst < comm_size) {
/* Send partial_scan to dst. Recv into tmp_buf */
mpi_errno = MPIC_Sendrecv(partial_scan, count, datatype,
dst, MPIR_EXSCAN_TAG, tmp_buf,
count, datatype, dst,
MPIR_EXSCAN_TAG, comm_ptr,
&status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
if (rank > dst) {
mpi_errno = MPIR_Reduce_local_impl( tmp_buf, partial_scan,
count, datatype, op );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* On rank 0, recvbuf is not defined. For sendbuf==MPI_IN_PLACE
recvbuf must not change (per MPI-2.2).
On rank 1, recvbuf is to be set equal to the value
in sendbuf on rank 0.
On others, recvbuf is the scan of values in the
sendbufs on lower ranks. */
if (rank != 0) {
if (flag == 0) {
/* simply copy data recd from rank 0 into recvbuf */
mpi_errno = MPIR_Localcopy(tmp_buf, count, datatype,
recvbuf, count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
flag = 1;
}
else {
mpi_errno = MPIR_Reduce_local_impl( tmp_buf,
recvbuf, count, datatype, op );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
}
}
else {
if (is_commutative) {
mpi_errno = MPIR_Reduce_local_impl( tmp_buf, partial_scan,
count, datatype, op );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
else {
mpi_errno = MPIR_Reduce_local_impl( partial_scan,
tmp_buf, count, datatype, op );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIR_Localcopy(tmp_buf, count, datatype,
partial_scan,
count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
}
}
mask <<= 1;
}
{
MPIR_Per_thread_t *per_thread = NULL;
int err = 0;
MPID_THREADPRIV_KEY_GET_ADDR(MPIR_ThreadInfo.isThreaded, MPIR_Per_thread_key,
MPIR_Per_thread, per_thread, &err);
MPIR_Assert(err == 0);
if (per_thread->op_errno)
mpi_errno = per_thread->op_errno;
}
fn_exit:
MPIR_CHKLMEM_FREEALL();
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag != MPIR_ERR_NONE)
MPIR_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Alltoallw_inter(const void *sendbuf, const int sendcounts[], const int sdispls[],
const MPI_Datatype sendtypes[], void *recvbuf, const int recvcounts[],
const int rdispls[], const MPI_Datatype recvtypes[], MPID_Comm *comm_ptr,
int *errflag)
{
/* Intercommunicator alltoallw. We use a pairwise exchange algorithm
similar to the one used in intracommunicator alltoallw. Since the
local and remote groups can be of different
sizes, we first compute the max of local_group_size,
remote_group_size. At step i, 0 <= i < max_size, each process
receives from src = (rank - i + max_size) % max_size if src <
remote_size, and sends to dst = (rank + i) % max_size if dst <
remote_size.
FIXME: change algorithm to match intracommunicator alltoallv
*/
int local_size, remote_size, max_size, i;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
int src, dst, rank, sendcount, recvcount;
char *sendaddr, *recvaddr;
MPI_Datatype sendtype, recvtype;
MPI_Comm comm;
local_size = comm_ptr->local_size;
remote_size = comm_ptr->remote_size;
comm = comm_ptr->handle;
rank = comm_ptr->rank;
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
/* Use pairwise exchange algorithm. */
max_size = MPIR_MAX(local_size, remote_size);
for (i=0; i<max_size; i++) {
src = (rank - i + max_size) % max_size;
dst = (rank + i) % max_size;
if (src >= remote_size) {
src = MPI_PROC_NULL;
recvaddr = NULL;
recvcount = 0;
recvtype = MPI_DATATYPE_NULL;
}
else {
recvaddr = (char *)recvbuf + rdispls[src];
recvcount = recvcounts[src];
recvtype = recvtypes[src];
}
if (dst >= remote_size) {
dst = MPI_PROC_NULL;
sendaddr = NULL;
sendcount = 0;
sendtype = MPI_DATATYPE_NULL;
}
else {
sendaddr = (char *)sendbuf+sdispls[dst];
sendcount = sendcounts[dst];
sendtype = sendtypes[dst];
}
mpi_errno = MPIC_Sendrecv(sendaddr, sendcount, sendtype,
dst, MPIR_ALLTOALLW_TAG, recvaddr,
recvcount, recvtype, src,
MPIR_ALLTOALLW_TAG, comm, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = TRUE;
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
fn_exit:
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_EXIT( comm_ptr );
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag)
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Alltoallv_inter(const void *sendbuf, const int *sendcounts, const int *sdispls,
MPI_Datatype sendtype, void *recvbuf, const int *recvcounts,
const int *rdispls, MPI_Datatype recvtype, MPID_Comm *comm_ptr,
MPIR_Errflag_t *errflag)
{
/* Intercommunicator alltoallv. We use a pairwise exchange algorithm
similar to the one used in intracommunicator alltoallv. Since the
local and remote groups can be of different
sizes, we first compute the max of local_group_size,
remote_group_size. At step i, 0 <= i < max_size, each process
receives from src = (rank - i + max_size) % max_size if src <
remote_size, and sends to dst = (rank + i) % max_size if dst <
remote_size.
FIXME: change algorithm to match intracommunicator alltoallv
*/
int local_size, remote_size, max_size, i;
MPI_Aint send_extent, recv_extent;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
int src, dst, rank, sendcount, recvcount;
char *sendaddr, *recvaddr;
local_size = comm_ptr->local_size;
remote_size = comm_ptr->remote_size;
rank = comm_ptr->rank;
/* Get extent of send and recv types */
MPID_Datatype_get_extent_macro(sendtype, send_extent);
MPID_Datatype_get_extent_macro(recvtype, recv_extent);
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
/* Use pairwise exchange algorithm. */
max_size = MPIR_MAX(local_size, remote_size);
for (i=0; i<max_size; i++) {
src = (rank - i + max_size) % max_size;
dst = (rank + i) % max_size;
if (src >= remote_size) {
src = MPI_PROC_NULL;
recvaddr = NULL;
recvcount = 0;
}
else {
MPIU_Ensure_Aint_fits_in_pointer(MPIU_VOID_PTR_CAST_TO_MPI_AINT recvbuf +
rdispls[src]*recv_extent);
recvaddr = (char *)recvbuf + rdispls[src]*recv_extent;
recvcount = recvcounts[src];
}
if (dst >= remote_size) {
dst = MPI_PROC_NULL;
sendaddr = NULL;
sendcount = 0;
}
else {
MPIU_Ensure_Aint_fits_in_pointer(MPIU_VOID_PTR_CAST_TO_MPI_AINT sendbuf +
sdispls[dst]*send_extent);
sendaddr = (char *)sendbuf + sdispls[dst]*send_extent;
sendcount = sendcounts[dst];
}
mpi_errno = MPIC_Sendrecv(sendaddr, sendcount, sendtype, dst,
MPIR_ALLTOALLV_TAG, recvaddr, recvcount,
recvtype, src, MPIR_ALLTOALLV_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
fn_exit:
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_EXIT( comm_ptr );
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag != MPIR_ERR_NONE)
MPIR_ERR_SET(mpi_errno, *errflag, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIDI_Comm_connect(const char *port_name, MPID_Info *info, int root,
MPID_Comm *comm_ptr, MPID_Comm **newcomm)
{
int mpi_errno=MPI_SUCCESS;
int j, i, rank, recv_ints[3], send_ints[3], context_id;
int remote_comm_size=0;
MPID_Comm *tmp_comm = NULL;
MPIDI_VC_t *new_vc = NULL;
int sendtag=100, recvtag=100, n_remote_pgs;
int n_local_pgs=1, local_comm_size;
pg_translation *local_translation = NULL, *remote_translation = NULL;
pg_node *pg_list = NULL;
MPIDI_PG_t **remote_pg = NULL;
MPIR_Context_id_t recvcontext_id = MPIR_INVALID_CONTEXT_ID;
int errflag = FALSE;
MPIU_CHKLMEM_DECL(3);
MPIDI_STATE_DECL(MPID_STATE_MPIDI_COMM_CONNECT);
MPIDI_FUNC_ENTER(MPID_STATE_MPIDI_COMM_CONNECT);
/* Get the context ID here because we need to send it to the remote side */
mpi_errno = MPIR_Get_contextid( comm_ptr, &recvcontext_id );
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
rank = comm_ptr->rank;
local_comm_size = comm_ptr->local_size;
if (rank == root)
{
/* Establish a communicator to communicate with the root on the
other side. */
mpi_errno = MPIDI_Create_inter_root_communicator_connect(
port_name, &tmp_comm, &new_vc);
if (mpi_errno != MPI_SUCCESS) {
MPIU_ERR_POP_LABEL(mpi_errno, no_port);
}
/* Make an array to translate local ranks to process group index
and rank */
MPIU_CHKLMEM_MALLOC(local_translation,pg_translation*,
local_comm_size*sizeof(pg_translation),
mpi_errno,"local_translation");
/* Make a list of the local communicator's process groups and encode
them in strings to be sent to the other side.
The encoded string for each process group contains the process
group id, size and all its KVS values */
mpi_errno = ExtractLocalPGInfo( comm_ptr, local_translation,
&pg_list, &n_local_pgs );
MPIU_ERR_CHKINTERNAL(mpi_errno, mpi_errno, "Can't extract local PG info.");
/* Send the remote root: n_local_pgs, local_comm_size,
Recv from the remote root: n_remote_pgs, remote_comm_size,
recvcontext_id for newcomm */
send_ints[0] = n_local_pgs;
send_ints[1] = local_comm_size;
send_ints[2] = recvcontext_id;
MPIU_DBG_MSG_FMT(CH3_CONNECT,VERBOSE,(MPIU_DBG_FDEST,
"sending 3 ints, %d, %d and %d, and receiving 3 ints",
send_ints[0], send_ints[1], send_ints[2]));
mpi_errno = MPIC_Sendrecv(send_ints, 3, MPI_INT, 0,
sendtag++, recv_ints, 3, MPI_INT,
0, recvtag++, tmp_comm->handle,
MPI_STATUS_IGNORE);
if (mpi_errno != MPI_SUCCESS) {
/* this is a no_port error because we may fail to connect
on the send if the port name is invalid */
MPIU_ERR_POP_LABEL(mpi_errno, no_port);
}
}
int MPIR_Alltoall_intra(
const void *sendbuf,
int sendcount,
MPI_Datatype sendtype,
void *recvbuf,
int recvcount,
MPI_Datatype recvtype,
MPIR_Comm *comm_ptr,
MPIR_Errflag_t *errflag )
{
int comm_size, i, j, pof2;
MPI_Aint sendtype_extent, recvtype_extent;
MPI_Aint recvtype_true_extent, recvbuf_extent, recvtype_true_lb;
int mpi_errno=MPI_SUCCESS, src, dst, rank, nbytes;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
int sendtype_size, block, *displs, count;
MPI_Aint pack_size, position;
MPI_Datatype newtype = MPI_DATATYPE_NULL;
void *tmp_buf;
MPIR_Request **reqarray;
MPI_Status *starray;
MPIR_CHKLMEM_DECL(6);
if (recvcount == 0) return MPI_SUCCESS;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
/* Get extent of send and recv types */
MPID_Datatype_get_extent_macro(recvtype, recvtype_extent);
MPID_Datatype_get_extent_macro(sendtype, sendtype_extent);
MPID_Datatype_get_size_macro(sendtype, sendtype_size);
nbytes = sendtype_size * sendcount;
if (sendbuf == MPI_IN_PLACE) {
/* We use pair-wise sendrecv_replace in order to conserve memory usage,
* which is keeping with the spirit of the MPI-2.2 Standard. But
* because of this approach all processes must agree on the global
* schedule of sendrecv_replace operations to avoid deadlock.
*
* Note that this is not an especially efficient algorithm in terms of
* time and there will be multiple repeated malloc/free's rather than
* maintaining a single buffer across the whole loop. Something like
* MADRE is probably the best solution for the MPI_IN_PLACE scenario. */
for (i = 0; i < comm_size; ++i) {
/* start inner loop at i to avoid re-exchanging data */
for (j = i; j < comm_size; ++j) {
if (rank == i) {
/* also covers the (rank == i && rank == j) case */
mpi_errno = MPIC_Sendrecv_replace(((char *)recvbuf + j*recvcount*recvtype_extent),
recvcount, recvtype,
j, MPIR_ALLTOALL_TAG,
j, MPIR_ALLTOALL_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
else if (rank == j) {
/* same as above with i/j args reversed */
mpi_errno = MPIC_Sendrecv_replace(((char *)recvbuf + i*recvcount*recvtype_extent),
recvcount, recvtype,
i, MPIR_ALLTOALL_TAG,
i, MPIR_ALLTOALL_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
}
}
}
else if ((nbytes <= MPIR_CVAR_ALLTOALL_SHORT_MSG_SIZE) && (comm_size >= 8)) {
/* use the indexing algorithm by Jehoshua Bruck et al,
* IEEE TPDS, Nov. 97 */
/* allocate temporary buffer */
MPIR_Pack_size_impl(recvcount*comm_size, recvtype, &pack_size);
MPIR_CHKLMEM_MALLOC(tmp_buf, void *, pack_size, mpi_errno, "tmp_buf");
/* Do Phase 1 of the algorithim. Shift the data blocks on process i
* upwards by a distance of i blocks. Store the result in recvbuf. */
mpi_errno = MPIR_Localcopy((char *) sendbuf +
rank*sendcount*sendtype_extent,
(comm_size - rank)*sendcount, sendtype, recvbuf,
(comm_size - rank)*recvcount, recvtype);
if (mpi_errno) { MPIR_ERR_POP(mpi_errno); }
mpi_errno = MPIR_Localcopy(sendbuf, rank*sendcount, sendtype,
(char *) recvbuf +
(comm_size-rank)*recvcount*recvtype_extent,
rank*recvcount, recvtype);
if (mpi_errno) { MPIR_ERR_POP(mpi_errno); }
/* Input data is now stored in recvbuf with datatype recvtype */
/* Now do Phase 2, the communication phase. It takes
ceiling(lg p) steps. In each step i, each process sends to rank+2^i
and receives from rank-2^i, and exchanges all data blocks
whose ith bit is 1. */
/* allocate displacements array for indexed datatype used in
communication */
MPIR_CHKLMEM_MALLOC(displs, int *, comm_size * sizeof(int), mpi_errno, "displs");
pof2 = 1;
while (pof2 < comm_size) {
dst = (rank + pof2) % comm_size;
src = (rank - pof2 + comm_size) % comm_size;
/* Exchange all data blocks whose ith bit is 1 */
/* Create an indexed datatype for the purpose */
count = 0;
for (block=1; block<comm_size; block++) {
if (block & pof2) {
displs[count] = block * recvcount;
count++;
}
}
mpi_errno = MPIR_Type_create_indexed_block_impl(count, recvcount,
displs, recvtype, &newtype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIR_Type_commit_impl(&newtype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
position = 0;
mpi_errno = MPIR_Pack_impl(recvbuf, 1, newtype, tmp_buf, pack_size, &position);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIC_Sendrecv(tmp_buf, position, MPI_PACKED, dst,
MPIR_ALLTOALL_TAG, recvbuf, 1, newtype,
src, MPIR_ALLTOALL_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
MPIR_Type_free_impl(&newtype);
pof2 *= 2;
}
/* Rotate blocks in recvbuf upwards by (rank + 1) blocks. Need
* a temporary buffer of the same size as recvbuf. */
/* get true extent of recvtype */
MPIR_Type_get_true_extent_impl(recvtype, &recvtype_true_lb, &recvtype_true_extent);
recvbuf_extent = recvcount * comm_size *
(MPL_MAX(recvtype_true_extent, recvtype_extent));
MPIR_CHKLMEM_MALLOC(tmp_buf, void *, recvbuf_extent, mpi_errno, "tmp_buf");
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - recvtype_true_lb);
mpi_errno = MPIR_Localcopy((char *) recvbuf + (rank+1)*recvcount*recvtype_extent,
(comm_size - rank - 1)*recvcount, recvtype, tmp_buf,
(comm_size - rank - 1)*recvcount, recvtype);
if (mpi_errno) { MPIR_ERR_POP(mpi_errno); }
mpi_errno = MPIR_Localcopy(recvbuf, (rank+1)*recvcount, recvtype,
(char *) tmp_buf + (comm_size-rank-1)*recvcount*recvtype_extent,
(rank+1)*recvcount, recvtype);
if (mpi_errno) { MPIR_ERR_POP(mpi_errno); }
/* Blocks are in the reverse order now (comm_size-1 to 0).
* Reorder them to (0 to comm_size-1) and store them in recvbuf. */
for (i=0; i<comm_size; i++){
mpi_errno = MPIR_Localcopy((char *) tmp_buf + i*recvcount*recvtype_extent,
recvcount, recvtype,
(char *) recvbuf + (comm_size-i-1)*recvcount*recvtype_extent,
recvcount, recvtype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
}
int MPIR_Alltoall_intra(
const void *sendbuf,
int sendcount,
MPI_Datatype sendtype,
void *recvbuf,
int recvcount,
MPI_Datatype recvtype,
MPID_Comm *comm_ptr,
mpir_errflag_t *errflag )
{
int comm_size, i, j, pof2;
MPI_Aint sendtype_extent, recvtype_extent;
MPI_Aint recvtype_true_extent, recvbuf_extent, recvtype_true_lb;
int mpi_errno=MPI_SUCCESS, src, dst, rank, nbytes;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
int sendtype_size, block, *displs, count;
MPI_Aint pack_size, position;
MPI_Datatype newtype = MPI_DATATYPE_NULL;
void *tmp_buf;
MPID_Request **reqarray;
MPI_Status *starray;
MPIU_CHKLMEM_DECL(6);
#ifdef MPIR_OLD_SHORT_ALLTOALL_ALG
MPI_Aint sendtype_true_extent, sendbuf_extent, sendtype_true_lb;
int k, p, curr_cnt, dst_tree_root, my_tree_root;
int last_recv_cnt, mask, tmp_mask, tree_root, nprocs_completed;
#endif
if (recvcount == 0) return MPI_SUCCESS;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
/* Get extent of send and recv types */
MPID_Datatype_get_extent_macro(recvtype, recvtype_extent);
MPID_Datatype_get_extent_macro(sendtype, sendtype_extent);
MPID_Datatype_get_size_macro(sendtype, sendtype_size);
nbytes = sendtype_size * sendcount;
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
if (sendbuf == MPI_IN_PLACE) {
/* We use pair-wise sendrecv_replace in order to conserve memory usage,
* which is keeping with the spirit of the MPI-2.2 Standard. But
* because of this approach all processes must agree on the global
* schedule of sendrecv_replace operations to avoid deadlock.
*
* Note that this is not an especially efficient algorithm in terms of
* time and there will be multiple repeated malloc/free's rather than
* maintaining a single buffer across the whole loop. Something like
* MADRE is probably the best solution for the MPI_IN_PLACE scenario. */
for (i = 0; i < comm_size; ++i) {
/* start inner loop at i to avoid re-exchanging data */
for (j = i; j < comm_size; ++j) {
if (rank == i) {
/* also covers the (rank == i && rank == j) case */
mpi_errno = MPIC_Sendrecv_replace(((char *)recvbuf + j*recvcount*recvtype_extent),
recvcount, recvtype,
j, MPIR_ALLTOALL_TAG,
j, MPIR_ALLTOALL_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
else if (rank == j) {
/* same as above with i/j args reversed */
mpi_errno = MPIC_Sendrecv_replace(((char *)recvbuf + i*recvcount*recvtype_extent),
recvcount, recvtype,
i, MPIR_ALLTOALL_TAG,
i, MPIR_ALLTOALL_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
}
}
}
else if ((nbytes <= MPIR_CVAR_ALLTOALL_SHORT_MSG_SIZE) && (comm_size >= 8)) {
/* use the indexing algorithm by Jehoshua Bruck et al,
* IEEE TPDS, Nov. 97 */
/* allocate temporary buffer */
MPIR_Pack_size_impl(recvcount*comm_size, recvtype, &pack_size);
MPIU_CHKLMEM_MALLOC(tmp_buf, void *, pack_size, mpi_errno, "tmp_buf");
/* Do Phase 1 of the algorithim. Shift the data blocks on process i
* upwards by a distance of i blocks. Store the result in recvbuf. */
mpi_errno = MPIR_Localcopy((char *) sendbuf +
rank*sendcount*sendtype_extent,
(comm_size - rank)*sendcount, sendtype, recvbuf,
(comm_size - rank)*recvcount, recvtype);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno); }
mpi_errno = MPIR_Localcopy(sendbuf, rank*sendcount, sendtype,
(char *) recvbuf +
(comm_size-rank)*recvcount*recvtype_extent,
rank*recvcount, recvtype);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno); }
/* Input data is now stored in recvbuf with datatype recvtype */
/* Now do Phase 2, the communication phase. It takes
ceiling(lg p) steps. In each step i, each process sends to rank+2^i
and receives from rank-2^i, and exchanges all data blocks
whose ith bit is 1. */
/* allocate displacements array for indexed datatype used in
communication */
MPIU_CHKLMEM_MALLOC(displs, int *, comm_size * sizeof(int), mpi_errno, "displs");
pof2 = 1;
while (pof2 < comm_size) {
dst = (rank + pof2) % comm_size;
src = (rank - pof2 + comm_size) % comm_size;
/* Exchange all data blocks whose ith bit is 1 */
/* Create an indexed datatype for the purpose */
count = 0;
for (block=1; block<comm_size; block++) {
if (block & pof2) {
displs[count] = block * recvcount;
count++;
}
}
mpi_errno = MPIR_Type_create_indexed_block_impl(count, recvcount,
displs, recvtype, &newtype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
mpi_errno = MPIR_Type_commit_impl(&newtype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
position = 0;
mpi_errno = MPIR_Pack_impl(recvbuf, 1, newtype, tmp_buf, pack_size, &position);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
mpi_errno = MPIC_Sendrecv(tmp_buf, position, MPI_PACKED, dst,
MPIR_ALLTOALL_TAG, recvbuf, 1, newtype,
src, MPIR_ALLTOALL_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
MPIR_Type_free_impl(&newtype);
pof2 *= 2;
}
/* Rotate blocks in recvbuf upwards by (rank + 1) blocks. Need
* a temporary buffer of the same size as recvbuf. */
/* get true extent of recvtype */
MPIR_Type_get_true_extent_impl(recvtype, &recvtype_true_lb, &recvtype_true_extent);
recvbuf_extent = recvcount * comm_size *
(MPIR_MAX(recvtype_true_extent, recvtype_extent));
MPIU_CHKLMEM_MALLOC(tmp_buf, void *, recvbuf_extent, mpi_errno, "tmp_buf");
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - recvtype_true_lb);
mpi_errno = MPIR_Localcopy((char *) recvbuf + (rank+1)*recvcount*recvtype_extent,
(comm_size - rank - 1)*recvcount, recvtype, tmp_buf,
(comm_size - rank - 1)*recvcount, recvtype);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno); }
mpi_errno = MPIR_Localcopy(recvbuf, (rank+1)*recvcount, recvtype,
(char *) tmp_buf + (comm_size-rank-1)*recvcount*recvtype_extent,
(rank+1)*recvcount, recvtype);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno); }
/* Blocks are in the reverse order now (comm_size-1 to 0).
* Reorder them to (0 to comm_size-1) and store them in recvbuf. */
for (i=0; i<comm_size; i++){
mpi_errno = MPIR_Localcopy((char *) tmp_buf + i*recvcount*recvtype_extent,
recvcount, recvtype,
(char *) recvbuf + (comm_size-i-1)*recvcount*recvtype_extent,
recvcount, recvtype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
#ifdef MPIR_OLD_SHORT_ALLTOALL_ALG
/* Short message. Use recursive doubling. Each process sends all
its data at each step along with all data it received in
previous steps. */
/* need to allocate temporary buffer of size
sendbuf_extent*comm_size */
/* get true extent of sendtype */
MPIR_Type_get_true_extent_impl(sendtype, &sendtype_true_lb, &sendtype_true_extent);
sendbuf_extent = sendcount * comm_size *
(MPIR_MAX(sendtype_true_extent, sendtype_extent));
MPIU_CHKLMEM_MALLOC(tmp_buf, void *, sendbuf_extent*comm_size, mpi_errno, "tmp_buf");
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - sendtype_true_lb);
/* copy local sendbuf into tmp_buf at location indexed by rank */
curr_cnt = sendcount*comm_size;
mpi_errno = MPIR_Localcopy(sendbuf, curr_cnt, sendtype,
((char *)tmp_buf + rank*sendbuf_extent),
curr_cnt, sendtype);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno);}
mask = 0x1;
i = 0;
while (mask < comm_size) {
dst = rank ^ mask;
dst_tree_root = dst >> i;
dst_tree_root <<= i;
my_tree_root = rank >> i;
my_tree_root <<= i;
if (dst < comm_size) {
mpi_errno = MPIC_Sendrecv(((char *)tmp_buf +
my_tree_root*sendbuf_extent),
curr_cnt, sendtype,
dst, MPIR_ALLTOALL_TAG,
((char *)tmp_buf +
dst_tree_root*sendbuf_extent),
sendbuf_extent*(comm_size-dst_tree_root),
sendtype, dst, MPIR_ALLTOALL_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
last_recv_cnt = 0;
} else
/* in case of non-power-of-two nodes, less data may be
received than specified */
MPIR_Get_count_impl(&status, sendtype, &last_recv_cnt);
curr_cnt += last_recv_cnt;
}
/* if some processes in this process's subtree in this step
did not have any destination process to communicate with
because of non-power-of-two, we need to send them the
result. We use a logarithmic recursive-halfing algorithm
for this. */
if (dst_tree_root + mask > comm_size) {
nprocs_completed = comm_size - my_tree_root - mask;
/* nprocs_completed is the number of processes in this
subtree that have all the data. Send data to others
in a tree fashion. First find root of current tree
that is being divided into two. k is the number of
least-significant bits in this process's rank that
must be zeroed out to find the rank of the root */
j = mask;
k = 0;
while (j) {
j >>= 1;
k++;
}
k--;
tmp_mask = mask >> 1;
while (tmp_mask) {
dst = rank ^ tmp_mask;
tree_root = rank >> k;
tree_root <<= k;
/* send only if this proc has data and destination
doesn't have data. at any step, multiple processes
can send if they have the data */
if ((dst > rank) &&
(rank < tree_root + nprocs_completed)
&& (dst >= tree_root + nprocs_completed)) {
/* send the data received in this step above */
mpi_errno = MPIC_Send(((char *)tmp_buf +
dst_tree_root*sendbuf_extent),
last_recv_cnt, sendtype,
dst, MPIR_ALLTOALL_TAG,
comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
/* recv only if this proc. doesn't have data and sender
has data */
else if ((dst < rank) &&
(dst < tree_root + nprocs_completed) &&
(rank >= tree_root + nprocs_completed)) {
mpi_errno = MPIC_Recv(((char *)tmp_buf +
dst_tree_root*sendbuf_extent),
sendbuf_extent*(comm_size-dst_tree_root),
sendtype,
dst, MPIR_ALLTOALL_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
last_recv_cnt = 0;
} else
MPIR_Get_count_impl(&status, sendtype, &last_recv_cnt);
curr_cnt += last_recv_cnt;
}
tmp_mask >>= 1;
k--;
}
}
mask <<= 1;
i++;
}
int MPIR_Intercomm_create_impl(MPIR_Comm *local_comm_ptr, int local_leader,
MPIR_Comm *peer_comm_ptr, int remote_leader, int tag,
MPIR_Comm **new_intercomm_ptr)
{
int mpi_errno = MPI_SUCCESS;
MPIR_Context_id_t final_context_id, recvcontext_id;
int remote_size = 0, *remote_lpids = NULL;
int comm_info[3];
int is_low_group = 0;
int cts_tag;
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPIR_COMM_KIND__INTERCOMM_CREATE_IMPL);
MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPIR_COMM_KIND__INTERCOMM_CREATE_IMPL);
/* Shift tag into the tagged coll space (tag provided by the user
is ignored as of MPI 3.0) */
cts_tag = MPIR_COMM_KIND__INTERCOMM_CREATE_TAG | MPIR_Process.tagged_coll_mask;
mpi_errno = MPID_Intercomm_exchange_map(local_comm_ptr, local_leader,
peer_comm_ptr, remote_leader,
&remote_size, &remote_lpids,
&is_low_group);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/*
* Create the contexts. Each group will have a context for sending
* to the other group. All processes must be involved. Because
* we know that the local and remote groups are disjoint, this
* step will complete
*/
MPL_DBG_MSG_FMT(MPIR_DBG_COMM,VERBOSE, (MPL_DBG_FDEST,"About to get contextid (local_size=%d) on rank %d",
local_comm_ptr->local_size, local_comm_ptr->rank ));
/* In the multi-threaded case, MPIR_Get_contextid_sparse assumes that the
calling routine already holds the single criticial section */
/* TODO: Make sure this is tag-safe */
mpi_errno = MPIR_Get_contextid_sparse( local_comm_ptr, &recvcontext_id, FALSE );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIR_Assert(recvcontext_id != 0);
MPL_DBG_MSG_FMT(MPIR_DBG_COMM,VERBOSE, (MPL_DBG_FDEST,"Got contextid=%d", recvcontext_id));
/* Leaders can now swap context ids and then broadcast the value
to the local group of processes */
if (local_comm_ptr->rank == local_leader) {
MPIR_Context_id_t remote_context_id;
mpi_errno = MPIC_Sendrecv( &recvcontext_id, 1, MPIR_CONTEXT_ID_T_DATATYPE, remote_leader, cts_tag,
&remote_context_id, 1, MPIR_CONTEXT_ID_T_DATATYPE, remote_leader, cts_tag,
peer_comm_ptr, MPI_STATUS_IGNORE, &errflag );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
final_context_id = remote_context_id;
/* Now, send all of our local processes the remote_lpids,
along with the final context id */
comm_info[0] = final_context_id;
MPL_DBG_MSG(MPIR_DBG_COMM,VERBOSE,"About to bcast on local_comm");
mpi_errno = MPID_Bcast( comm_info, 1, MPI_INT, local_leader, local_comm_ptr, &errflag );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIR_ERR_CHKANDJUMP(errflag, mpi_errno, MPI_ERR_OTHER, "**coll_fail");
MPL_DBG_MSG_D(MPIR_DBG_COMM,VERBOSE,"end of bcast on local_comm of size %d",
local_comm_ptr->local_size );
}
else
{
/* we're the other processes */
MPL_DBG_MSG(MPIR_DBG_COMM,VERBOSE,"About to receive bcast on local_comm");
mpi_errno = MPID_Bcast( comm_info, 1, MPI_INT, local_leader, local_comm_ptr, &errflag );
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
MPIR_ERR_CHKANDJUMP(errflag, mpi_errno, MPI_ERR_OTHER, "**coll_fail");
/* Extract the context and group sign informatin */
final_context_id = comm_info[0];
}
/* At last, we now have the information that we need to build the
intercommunicator */
/* All processes in the local_comm now build the communicator */
mpi_errno = MPIR_Comm_create( new_intercomm_ptr );
if (mpi_errno) goto fn_fail;
(*new_intercomm_ptr)->context_id = final_context_id;
(*new_intercomm_ptr)->recvcontext_id = recvcontext_id;
(*new_intercomm_ptr)->remote_size = remote_size;
(*new_intercomm_ptr)->local_size = local_comm_ptr->local_size;
(*new_intercomm_ptr)->pof2 = local_comm_ptr->pof2;
(*new_intercomm_ptr)->rank = local_comm_ptr->rank;
(*new_intercomm_ptr)->comm_kind = MPIR_COMM_KIND__INTERCOMM;
(*new_intercomm_ptr)->local_comm = 0;
(*new_intercomm_ptr)->is_low_group = is_low_group;
mpi_errno = MPID_Create_intercomm_from_lpids( *new_intercomm_ptr, remote_size, remote_lpids );
if (mpi_errno) goto fn_fail;
MPIR_Comm_map_dup(*new_intercomm_ptr, local_comm_ptr, MPIR_COMM_MAP_DIR__L2L);
/* Inherit the error handler (if any) */
MPID_THREAD_CS_ENTER(POBJ, MPIR_THREAD_POBJ_COMM_MUTEX(local_comm_ptr));
(*new_intercomm_ptr)->errhandler = local_comm_ptr->errhandler;
if (local_comm_ptr->errhandler) {
MPIR_Errhandler_add_ref( local_comm_ptr->errhandler );
}
MPID_THREAD_CS_EXIT(POBJ, MPIR_THREAD_POBJ_COMM_MUTEX(local_comm_ptr));
mpi_errno = MPIR_Comm_commit(*new_intercomm_ptr);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
fn_exit:
if (remote_lpids) {
MPL_free(remote_lpids);
remote_lpids = NULL;
}
MPIR_FUNC_TERSE_EXIT(MPID_STATE_MPIR_COMM_KIND__INTERCOMM_CREATE_IMPL);
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Intercomm_merge_impl(MPIR_Comm * comm_ptr, int high, MPIR_Comm ** new_intracomm_ptr)
{
int mpi_errno = MPI_SUCCESS;
int local_high, remote_high, new_size;
MPIR_Context_id_t new_context_id;
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPIR_COMM_KIND__INTERCOMM_MERGE_IMPL);
MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPIR_COMM_KIND__INTERCOMM_MERGE_IMPL);
/* Make sure that we have a local intercommunicator */
if (!comm_ptr->local_comm) {
/* Manufacture the local communicator */
mpi_errno = MPII_Setup_intercomm_localcomm(comm_ptr);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
}
/* Find the "high" value of the other group of processes. This
* will be used to determine which group is ordered first in
* the generated communicator. high is logical */
local_high = high;
if (comm_ptr->rank == 0) {
/* This routine allows use to use the collective communication
* context rather than the point-to-point context. */
mpi_errno = MPIC_Sendrecv(&local_high, 1, MPI_INT, 0, 0,
&remote_high, 1, MPI_INT, 0, 0, comm_ptr,
MPI_STATUS_IGNORE, &errflag);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
/* If local_high and remote_high are the same, then order is arbitrary.
* we use the is_low_group in the intercomm in this case. */
MPL_DBG_MSG_FMT(MPIR_DBG_COMM, VERBOSE,
(MPL_DBG_FDEST, "local_high=%d remote_high=%d is_low_group=%d",
local_high, remote_high, comm_ptr->is_low_group));
if (local_high == remote_high) {
local_high = !(comm_ptr->is_low_group);
}
}
/*
* All processes in the local group now need to get the
* value of local_high, which may have changed if both groups
* of processes had the same value for high
*/
mpi_errno = MPIR_Bcast(&local_high, 1, MPI_INT, 0, comm_ptr->local_comm, &errflag);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
MPIR_ERR_CHKANDJUMP(errflag, mpi_errno, MPI_ERR_OTHER, "**coll_fail");
/*
* For the intracomm, we need a consistent context id.
* That means that one of the two groups needs to use
* the recvcontext_id and the other must use the context_id
* The recvcontext_id is unique on each process, but another
* communicator may use the context_id. Therefore, we do a small hack.
* We set both flags indicating a sub-communicator (intra-node and
* inter-node) to one. This is normally not possible (a communicator
* is either intra- or inter-node) - which makes this context_id unique.
*
*/
new_size = comm_ptr->local_size + comm_ptr->remote_size;
mpi_errno = MPIR_Comm_create(new_intracomm_ptr);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
if (local_high) {
(*new_intracomm_ptr)->context_id =
MPIR_CONTEXT_SET_FIELD(SUBCOMM, comm_ptr->recvcontext_id, 3);
} else {
(*new_intracomm_ptr)->context_id = MPIR_CONTEXT_SET_FIELD(SUBCOMM, comm_ptr->context_id, 3);
}
(*new_intracomm_ptr)->recvcontext_id = (*new_intracomm_ptr)->context_id;
(*new_intracomm_ptr)->remote_size = (*new_intracomm_ptr)->local_size = new_size;
(*new_intracomm_ptr)->pof2 = MPL_pof2(new_size);
(*new_intracomm_ptr)->rank = -1;
(*new_intracomm_ptr)->comm_kind = MPIR_COMM_KIND__INTRACOMM;
/* Now we know which group comes first. Build the new mapping
* from the existing comm */
mpi_errno = create_and_map(comm_ptr, local_high, (*new_intracomm_ptr));
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
/* We've setup a temporary context id, based on the context id
* used by the intercomm. This allows us to perform the allreduce
* operations within the context id algorithm, since we already
* have a valid (almost - see comm_create_hook) communicator.
*/
mpi_errno = MPIR_Comm_commit((*new_intracomm_ptr));
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
/* printf("About to get context id \n"); fflush(stdout); */
/* In the multi-threaded case, MPIR_Get_contextid_sparse assumes that the
* calling routine already holds the single criticial section */
new_context_id = 0;
mpi_errno = MPIR_Get_contextid_sparse((*new_intracomm_ptr), &new_context_id, FALSE);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
MPIR_Assert(new_context_id != 0);
/* We release this communicator that was involved just to
* get valid context id and create true one
*/
mpi_errno = MPIR_Comm_release(*new_intracomm_ptr);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIR_Comm_create(new_intracomm_ptr);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
(*new_intracomm_ptr)->remote_size = (*new_intracomm_ptr)->local_size = new_size;
(*new_intracomm_ptr)->pof2 = MPL_pof2(new_size);
(*new_intracomm_ptr)->rank = -1;
(*new_intracomm_ptr)->comm_kind = MPIR_COMM_KIND__INTRACOMM;
(*new_intracomm_ptr)->context_id = new_context_id;
(*new_intracomm_ptr)->recvcontext_id = new_context_id;
mpi_errno = create_and_map(comm_ptr, local_high, (*new_intracomm_ptr));
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
mpi_errno = MPIR_Comm_commit((*new_intracomm_ptr));
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
fn_exit:
MPIR_FUNC_TERSE_EXIT(MPID_STATE_MPIR_COMM_KIND__INTERCOMM_MERGE_IMPL);
return mpi_errno;
fn_fail:
goto fn_exit;
}
/* Algorithm: Recursive halving
*
* This is a recursive-halving algorithm in which the first p/2 processes send
* the second n/2 data to their counterparts in the other half and receive the
* first n/2 data from them. This procedure continues recursively, halving the
* data communicated at each step, for a total of lgp steps. If the number of
* processes is not a power-of-two, we convert it to the nearest lower
* power-of-two by having the first few even-numbered processes send their data
* to the neighboring odd-numbered process at (rank+1). Those odd-numbered
* processes compute the result for their left neighbor as well in the
* recursive halving algorithm, and then at the end send the result back to
* the processes that didn't participate. Therefore, if p is a power-of-two:
*
* Cost = lgp.alpha + n.((p-1)/p).beta + n.((p-1)/p).gamma
*
* If p is not a power-of-two:
*
* Cost = (floor(lgp)+2).alpha + n.(1+(p-1+n)/p).beta + n.(1+(p-1)/p).gamma
*
* The above cost in the non power-of-two case is approximate because there is
* some imbalance in the amount of work each process does because some
* processes do the work of their neighbors as well.
*/
int MPIR_Reduce_scatter_block_intra_recursive_halving (
const void *sendbuf,
void *recvbuf,
int recvcount,
MPI_Datatype datatype,
MPI_Op op,
MPIR_Comm *comm_ptr,
MPIR_Errflag_t *errflag )
{
int rank, comm_size, i;
MPI_Aint extent, true_extent, true_lb;
int *disps;
void *tmp_recvbuf, *tmp_results;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
int total_count, dst;
int mask;
int *newcnts, *newdisps, rem, newdst, send_idx, recv_idx,
last_idx, send_cnt, recv_cnt;
int pof2, old_i, newrank;
MPIR_CHKLMEM_DECL(5);
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
#ifdef HAVE_ERROR_CHECKING
{
int is_commutative;
is_commutative = MPIR_Op_is_commutative(op);
MPIR_Assert(is_commutative);
}
#endif /* HAVE_ERROR_CHECKING */
/* set op_errno to 0. stored in perthread structure */
{
MPIR_Per_thread_t *per_thread = NULL;
int err = 0;
MPID_THREADPRIV_KEY_GET_ADDR(MPIR_ThreadInfo.isThreaded, MPIR_Per_thread_key,
MPIR_Per_thread, per_thread, &err);
MPIR_Assert(err == 0);
per_thread->op_errno = 0;
}
if (recvcount == 0) {
goto fn_exit;
}
MPIR_Datatype_get_extent_macro(datatype, extent);
MPIR_Type_get_true_extent_impl(datatype, &true_lb, &true_extent);
MPIR_CHKLMEM_MALLOC(disps, int *, comm_size * sizeof(int), mpi_errno, "disps", MPL_MEM_BUFFER);
total_count = comm_size*recvcount;
for (i=0; i<comm_size; i++) {
disps[i] = i*recvcount;
}
/* total_count*extent eventually gets malloced. it isn't added to
* a user-passed in buffer */
MPIR_Ensure_Aint_fits_in_pointer(total_count * MPL_MAX(true_extent, extent));
/* commutative and short. use recursive halving algorithm */
/* allocate temp. buffer to receive incoming data */
MPIR_CHKLMEM_MALLOC(tmp_recvbuf, void *, total_count*(MPL_MAX(true_extent,extent)), mpi_errno, "tmp_recvbuf", MPL_MEM_BUFFER);
/* adjust for potential negative lower bound in datatype */
tmp_recvbuf = (void *)((char*)tmp_recvbuf - true_lb);
/* need to allocate another temporary buffer to accumulate
results because recvbuf may not be big enough */
MPIR_CHKLMEM_MALLOC(tmp_results, void *, total_count*(MPL_MAX(true_extent,extent)), mpi_errno, "tmp_results", MPL_MEM_BUFFER);
/* adjust for potential negative lower bound in datatype */
tmp_results = (void *)((char*)tmp_results - true_lb);
/* copy sendbuf into tmp_results */
if (sendbuf != MPI_IN_PLACE)
mpi_errno = MPIR_Localcopy(sendbuf, total_count, datatype,
tmp_results, total_count, datatype);
else
mpi_errno = MPIR_Localcopy(recvbuf, total_count, datatype,
tmp_results, total_count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
pof2 = comm_ptr->pof2;
rem = comm_size - pof2;
/* In the non-power-of-two case, all even-numbered
processes of rank < 2*rem send their data to
(rank+1). These even-numbered processes no longer
participate in the algorithm until the very end. The
remaining processes form a nice power-of-two. */
if (rank < 2*rem) {
if (rank % 2 == 0) { /* even */
mpi_errno = MPIC_Send(tmp_results, total_count,
datatype, rank+1,
MPIR_REDUCE_SCATTER_BLOCK_TAG, comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* temporarily set the rank to -1 so that this
process does not pariticipate in recursive
doubling */
newrank = -1;
}
else { /* odd */
mpi_errno = MPIC_Recv(tmp_recvbuf, total_count,
datatype, rank-1,
MPIR_REDUCE_SCATTER_BLOCK_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* do the reduction on received data. since the
ordering is right, it doesn't matter whether
the operation is commutative or not. */
mpi_errno = MPIR_Reduce_local( tmp_recvbuf, tmp_results,
total_count, datatype, op);
/* change the rank */
newrank = rank / 2;
}
}
else /* rank >= 2*rem */
newrank = rank - rem;
if (newrank != -1) {
/* recalculate the recvcnts and disps arrays because the
even-numbered processes who no longer participate will
have their result calculated by the process to their
right (rank+1). */
MPIR_CHKLMEM_MALLOC(newcnts, int *, pof2*sizeof(int), mpi_errno, "newcnts", MPL_MEM_BUFFER);
MPIR_CHKLMEM_MALLOC(newdisps, int *, pof2*sizeof(int), mpi_errno, "newdisps", MPL_MEM_BUFFER);
for (i=0; i<pof2; i++) {
/* what does i map to in the old ranking? */
old_i = (i < rem) ? i*2 + 1 : i + rem;
if (old_i < 2*rem) {
/* This process has to also do its left neighbor's
work */
newcnts[i] = 2 * recvcount;
}
else
newcnts[i] = recvcount;
}
newdisps[0] = 0;
for (i=1; i<pof2; i++)
newdisps[i] = newdisps[i-1] + newcnts[i-1];
mask = pof2 >> 1;
send_idx = recv_idx = 0;
last_idx = pof2;
while (mask > 0) {
newdst = newrank ^ mask;
/* find real rank of dest */
dst = (newdst < rem) ? newdst*2 + 1 : newdst + rem;
send_cnt = recv_cnt = 0;
if (newrank < newdst) {
send_idx = recv_idx + mask;
for (i=send_idx; i<last_idx; i++)
send_cnt += newcnts[i];
for (i=recv_idx; i<send_idx; i++)
recv_cnt += newcnts[i];
}
else {
recv_idx = send_idx + mask;
for (i=send_idx; i<recv_idx; i++)
send_cnt += newcnts[i];
for (i=recv_idx; i<last_idx; i++)
recv_cnt += newcnts[i];
}
/* printf("Rank %d, send_idx %d, recv_idx %d, send_cnt %d, recv_cnt %d, last_idx %d\n", newrank, send_idx, recv_idx,
send_cnt, recv_cnt, last_idx);
*/
/* Send data from tmp_results. Recv into tmp_recvbuf */
if ((send_cnt != 0) && (recv_cnt != 0))
mpi_errno = MPIC_Sendrecv((char *) tmp_results +
newdisps[send_idx]*extent,
send_cnt, datatype,
dst, MPIR_REDUCE_SCATTER_BLOCK_TAG,
(char *) tmp_recvbuf +
newdisps[recv_idx]*extent,
recv_cnt, datatype, dst,
MPIR_REDUCE_SCATTER_BLOCK_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
else if ((send_cnt == 0) && (recv_cnt != 0))
mpi_errno = MPIC_Recv((char *) tmp_recvbuf +
newdisps[recv_idx]*extent,
recv_cnt, datatype, dst,
MPIR_REDUCE_SCATTER_BLOCK_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
else if ((recv_cnt == 0) && (send_cnt != 0))
mpi_errno = MPIC_Send((char *) tmp_results +
newdisps[send_idx]*extent,
send_cnt, datatype,
dst, MPIR_REDUCE_SCATTER_BLOCK_TAG,
comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* tmp_recvbuf contains data received in this step.
tmp_results contains data accumulated so far */
if (recv_cnt) {
mpi_errno = MPIR_Reduce_local(
(char *) tmp_recvbuf + newdisps[recv_idx]*extent,
(char *) tmp_results + newdisps[recv_idx]*extent,
recv_cnt, datatype, op);
}
/* update send_idx for next iteration */
send_idx = recv_idx;
last_idx = recv_idx + mask;
mask >>= 1;
}
/* copy this process's result from tmp_results to recvbuf */
mpi_errno = MPIR_Localcopy((char *)tmp_results +
disps[rank]*extent,
recvcount, datatype, recvbuf,
recvcount, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
static int MPIR_Reduce_scatter_block_noncomm (
const void *sendbuf,
void *recvbuf,
int recvcount,
MPI_Datatype datatype,
MPI_Op op,
MPIR_Comm *comm_ptr,
MPIR_Errflag_t *errflag )
{
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
int comm_size = comm_ptr->local_size;
int rank = comm_ptr->rank;
int pof2;
int log2_comm_size;
int i, k;
int recv_offset, send_offset;
int block_size, total_count, size;
MPI_Aint true_extent, true_lb;
int buf0_was_inout;
void *tmp_buf0;
void *tmp_buf1;
void *result_ptr;
MPIR_CHKLMEM_DECL(3);
MPIR_Type_get_true_extent_impl(datatype, &true_lb, &true_extent);
pof2 = 1;
log2_comm_size = 0;
while (pof2 < comm_size) {
pof2 <<= 1;
++log2_comm_size;
}
/* begin error checking */
MPIR_Assert(pof2 == comm_size); /* FIXME this version only works for power of 2 procs */
/* end error checking */
/* size of a block (count of datatype per block, NOT bytes per block) */
block_size = recvcount;
total_count = block_size * comm_size;
MPIR_CHKLMEM_MALLOC(tmp_buf0, void *, true_extent * total_count, mpi_errno, "tmp_buf0");
MPIR_CHKLMEM_MALLOC(tmp_buf1, void *, true_extent * total_count, mpi_errno, "tmp_buf1");
/* adjust for potential negative lower bound in datatype */
tmp_buf0 = (void *)((char*)tmp_buf0 - true_lb);
tmp_buf1 = (void *)((char*)tmp_buf1 - true_lb);
/* Copy our send data to tmp_buf0. We do this one block at a time and
permute the blocks as we go according to the mirror permutation. */
for (i = 0; i < comm_size; ++i) {
mpi_errno = MPIR_Localcopy((char *)(sendbuf == MPI_IN_PLACE ? (const void *)recvbuf : sendbuf) + (i * true_extent * block_size),
block_size, datatype,
(char *)tmp_buf0 + (MPIU_Mirror_permutation(i, log2_comm_size) * true_extent * block_size), block_size, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
buf0_was_inout = 1;
send_offset = 0;
recv_offset = 0;
size = total_count;
for (k = 0; k < log2_comm_size; ++k) {
/* use a double-buffering scheme to avoid local copies */
char *incoming_data = (buf0_was_inout ? tmp_buf1 : tmp_buf0);
char *outgoing_data = (buf0_was_inout ? tmp_buf0 : tmp_buf1);
int peer = rank ^ (0x1 << k);
size /= 2;
if (rank > peer) {
/* we have the higher rank: send top half, recv bottom half */
recv_offset += size;
}
else {
/* we have the lower rank: recv top half, send bottom half */
send_offset += size;
}
mpi_errno = MPIC_Sendrecv(outgoing_data + send_offset*true_extent,
size, datatype, peer, MPIR_REDUCE_SCATTER_BLOCK_TAG,
incoming_data + recv_offset*true_extent,
size, datatype, peer, MPIR_REDUCE_SCATTER_BLOCK_TAG,
comm_ptr, MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* always perform the reduction at recv_offset, the data at send_offset
is now our peer's responsibility */
if (rank > peer) {
/* higher ranked value so need to call op(received_data, my_data) */
mpi_errno = MPIR_Reduce_local_impl(
incoming_data + recv_offset*true_extent,
outgoing_data + recv_offset*true_extent,
size, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
else {
/* lower ranked value so need to call op(my_data, received_data) */
mpi_errno = MPIR_Reduce_local_impl(
outgoing_data + recv_offset*true_extent,
incoming_data + recv_offset*true_extent,
size, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
buf0_was_inout = !buf0_was_inout;
}
/* the next round of send/recv needs to happen within the block (of size
"size") that we just received and reduced */
send_offset = recv_offset;
}
MPIR_Assert(size == recvcount);
/* copy the reduced data to the recvbuf */
result_ptr = (char *)(buf0_was_inout ? tmp_buf0 : tmp_buf1) + recv_offset * true_extent;
mpi_errno = MPIR_Localcopy(result_ptr, size, datatype,
recvbuf, size, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
fn_exit:
MPIR_CHKLMEM_FREEALL();
/* --BEGIN ERROR HANDLING-- */
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag != MPIR_ERR_NONE)
MPIR_ERR_SET(mpi_errno, *errflag, "**coll_fail");
/* --END ERROR HANDLING-- */
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Alltoallw_intra(const void *sendbuf, const int sendcounts[], const int sdispls[],
const MPI_Datatype sendtypes[], void *recvbuf, const int recvcounts[],
const int rdispls[], const MPI_Datatype recvtypes[], MPID_Comm *comm_ptr,
int *errflag)
{
int comm_size, i, j;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
MPI_Status *starray;
MPI_Request *reqarray;
int dst, rank;
MPI_Comm comm;
int outstanding_requests;
int ii, ss, bblock;
int type_size;
MPIU_CHKLMEM_DECL(2);
comm = comm_ptr->handle;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
if (sendbuf == MPI_IN_PLACE) {
/* We use pair-wise sendrecv_replace in order to conserve memory usage,
* which is keeping with the spirit of the MPI-2.2 Standard. But
* because of this approach all processes must agree on the global
* schedule of sendrecv_replace operations to avoid deadlock.
*
* Note that this is not an especially efficient algorithm in terms of
* time and there will be multiple repeated malloc/free's rather than
* maintaining a single buffer across the whole loop. Something like
* MADRE is probably the best solution for the MPI_IN_PLACE scenario. */
for (i = 0; i < comm_size; ++i) {
/* start inner loop at i to avoid re-exchanging data */
for (j = i; j < comm_size; ++j) {
if (rank == i) {
/* also covers the (rank == i && rank == j) case */
mpi_errno = MPIC_Sendrecv_replace(((char *)recvbuf + rdispls[j]),
recvcounts[j], recvtypes[j],
j, MPIR_ALLTOALLW_TAG,
j, MPIR_ALLTOALLW_TAG,
comm, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = TRUE;
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
else if (rank == j) {
/* same as above with i/j args reversed */
mpi_errno = MPIC_Sendrecv_replace(((char *)recvbuf + rdispls[i]),
recvcounts[i], recvtypes[i],
i, MPIR_ALLTOALLW_TAG,
i, MPIR_ALLTOALLW_TAG,
comm, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = TRUE;
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
}
}
}
else {
bblock = MPIR_CVAR_ALLTOALL_THROTTLE;
if (bblock == 0) bblock = comm_size;
MPIU_CHKLMEM_MALLOC(starray, MPI_Status*, 2*bblock*sizeof(MPI_Status), mpi_errno, "starray");
MPIU_CHKLMEM_MALLOC(reqarray, MPI_Request*, 2*bblock*sizeof(MPI_Request), mpi_errno, "reqarray");
/* post only bblock isends/irecvs at a time as suggested by Tony Ladd */
for (ii=0; ii<comm_size; ii+=bblock) {
outstanding_requests = 0;
ss = comm_size-ii < bblock ? comm_size-ii : bblock;
/* do the communication -- post ss sends and receives: */
for ( i=0; i<ss; i++ ) {
dst = (rank+i+ii) % comm_size;
if (recvcounts[dst]) {
MPID_Datatype_get_size_macro(recvtypes[dst], type_size);
if (type_size) {
mpi_errno = MPIC_Irecv((char *)recvbuf+rdispls[dst],
recvcounts[dst], recvtypes[dst], dst,
MPIR_ALLTOALLW_TAG, comm,
&reqarray[outstanding_requests]);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno); }
outstanding_requests++;
}
}
}
for ( i=0; i<ss; i++ ) {
dst = (rank-i-ii+comm_size) % comm_size;
if (sendcounts[dst]) {
MPID_Datatype_get_size_macro(sendtypes[dst], type_size);
if (type_size) {
mpi_errno = MPIC_Isend((char *)sendbuf+sdispls[dst],
sendcounts[dst], sendtypes[dst], dst,
MPIR_ALLTOALLW_TAG, comm,
&reqarray[outstanding_requests], errflag);
if (mpi_errno) { MPIU_ERR_POP(mpi_errno); }
outstanding_requests++;
}
}
}
mpi_errno = MPIC_Waitall(outstanding_requests, reqarray, starray, errflag);
if (mpi_errno && mpi_errno != MPI_ERR_IN_STATUS) MPIU_ERR_POP(mpi_errno);
/* --BEGIN ERROR HANDLING-- */
if (mpi_errno == MPI_ERR_IN_STATUS) {
for (i=0; i<outstanding_requests; i++) {
if (starray[i].MPI_ERROR != MPI_SUCCESS) {
mpi_errno = starray[i].MPI_ERROR;
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = TRUE;
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
}
}
/* --END ERROR HANDLING-- */
}
#ifdef FOO
/* Use pairwise exchange algorithm. */
/* Make local copy first */
mpi_errno = MPIR_Localcopy(((char *)sendbuf+sdispls[rank]),
sendcounts[rank], sendtypes[rank],
((char *)recvbuf+rdispls[rank]),
recvcounts[rank], recvtypes[rank]);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
/* Do the pairwise exchange. */
for (i=1; i<comm_size; i++) {
src = (rank - i + comm_size) % comm_size;
dst = (rank + i) % comm_size;
mpi_errno = MPIC_Sendrecv(((char *)sendbuf+sdispls[dst]),
sendcounts[dst], sendtypes[dst], dst,
MPIR_ALLTOALLW_TAG,
((char *)recvbuf+rdispls[src]),
recvcounts[src], recvtypes[dst], src,
MPIR_ALLTOALLW_TAG, comm, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = TRUE;
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
#endif
}
/* check if multiple threads are calling this collective function */
fn_exit:
MPIDU_ERR_CHECK_MULTIPLE_THREADS_EXIT( comm_ptr );
MPIU_CHKLMEM_FREEALL();
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag)
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
static int MPIR_Scan_generic (
const void *sendbuf,
void *recvbuf,
int count,
MPI_Datatype datatype,
MPI_Op op,
MPID_Comm *comm_ptr,
int *errflag )
{
MPI_Status status;
int rank, comm_size;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
int mask, dst, is_commutative;
MPI_Aint true_extent, true_lb, extent;
void *partial_scan, *tmp_buf;
MPID_Op *op_ptr;
MPI_Comm comm;
MPIU_THREADPRIV_DECL;
MPIU_CHKLMEM_DECL(2);
if (count == 0) return MPI_SUCCESS;
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
comm = comm_ptr->handle;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
MPIU_THREADPRIV_GET;
/* set op_errno to 0. stored in perthread structure */
MPIU_THREADPRIV_FIELD(op_errno) = 0;
if (HANDLE_GET_KIND(op) == HANDLE_KIND_BUILTIN) {
is_commutative = 1;
}
else {
MPID_Op_get_ptr(op, op_ptr);
if (op_ptr->kind == MPID_OP_USER_NONCOMMUTE)
is_commutative = 0;
else
is_commutative = 1;
}
/* need to allocate temporary buffer to store partial scan*/
MPIR_Type_get_true_extent_impl(datatype, &true_lb, &true_extent);
MPID_Datatype_get_extent_macro(datatype, extent);
MPIU_CHKLMEM_MALLOC(partial_scan, void *, count*(MPIR_MAX(extent,true_extent)), mpi_errno, "partial_scan");
/* This eventually gets malloc()ed as a temp buffer, not added to
* any user buffers */
MPID_Ensure_Aint_fits_in_pointer(count * MPIR_MAX(extent, true_extent));
/* adjust for potential negative lower bound in datatype */
partial_scan = (void *)((char*)partial_scan - true_lb);
/* need to allocate temporary buffer to store incoming data*/
MPIU_CHKLMEM_MALLOC(tmp_buf, void *, count*(MPIR_MAX(extent,true_extent)), mpi_errno, "tmp_buf");
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - true_lb);
/* Since this is an inclusive scan, copy local contribution into
recvbuf. */
if (sendbuf != MPI_IN_PLACE) {
mpi_errno = MPIR_Localcopy(sendbuf, count, datatype,
recvbuf, count, datatype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
if (sendbuf != MPI_IN_PLACE)
mpi_errno = MPIR_Localcopy(sendbuf, count, datatype,
partial_scan, count, datatype);
else
mpi_errno = MPIR_Localcopy(recvbuf, count, datatype,
partial_scan, count, datatype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
mask = 0x1;
while (mask < comm_size) {
dst = rank ^ mask;
if (dst < comm_size) {
/* Send partial_scan to dst. Recv into tmp_buf */
mpi_errno = MPIC_Sendrecv(partial_scan, count, datatype,
dst, MPIR_SCAN_TAG, tmp_buf,
count, datatype, dst,
MPIR_SCAN_TAG, comm,
&status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = TRUE;
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
if (rank > dst) {
mpi_errno = MPIR_Reduce_local_impl(
tmp_buf, partial_scan, count, datatype, op);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
mpi_errno = MPIR_Reduce_local_impl(
tmp_buf, recvbuf, count, datatype, op);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
else {
if (is_commutative) {
mpi_errno = MPIR_Reduce_local_impl(
tmp_buf, partial_scan, count, datatype, op);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
else {
mpi_errno = MPIR_Reduce_local_impl(
partial_scan, tmp_buf, count, datatype, op);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
mpi_errno = MPIR_Localcopy(tmp_buf, count, datatype,
partial_scan,
count, datatype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
}
}
mask <<= 1;
}
if (MPIU_THREADPRIV_FIELD(op_errno)) {
mpi_errno = MPIU_THREADPRIV_FIELD(op_errno);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
fn_exit:
MPIU_CHKLMEM_FREEALL();
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_EXIT( comm_ptr );
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag)
MPIU_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Allgatherv_intra (
const void *sendbuf,
int sendcount,
MPI_Datatype sendtype,
void *recvbuf,
const int *recvcounts,
const int *displs,
MPI_Datatype recvtype,
MPID_Comm *comm_ptr,
mpir_errflag_t *errflag )
{
int comm_size, rank, j, i, left, right;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
MPI_Aint recvbuf_extent, recvtype_extent, recvtype_true_extent,
recvtype_true_lb;
int curr_cnt, send_cnt, dst, total_count, recvtype_size, pof2, src, rem;
int recv_cnt;
void *tmp_buf;
int mask, dst_tree_root, my_tree_root, is_homogeneous, position,
send_offset, recv_offset, last_recv_cnt, nprocs_completed, k,
offset, tmp_mask, tree_root;
#ifdef MPID_HAS_HETERO
int tmp_buf_size, nbytes;
#endif
MPIU_CHKLMEM_DECL(1);
/* check if multiple threads are calling this collective function */
MPIDU_ERR_CHECK_MULTIPLE_THREADS_ENTER( comm_ptr );
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
total_count = 0;
for (i=0; i<comm_size; i++)
total_count += recvcounts[i];
if (total_count == 0) goto fn_exit;
MPID_Datatype_get_extent_macro( recvtype, recvtype_extent );
MPID_Datatype_get_size_macro(recvtype, recvtype_size);
if ((total_count*recvtype_size < MPIR_CVAR_ALLGATHER_LONG_MSG_SIZE) &&
!(comm_size & (comm_size - 1))) {
/* Short or medium size message and power-of-two no. of processes. Use
* recursive doubling algorithm */
is_homogeneous = 1;
#ifdef MPID_HAS_HETERO
if (comm_ptr->is_hetero)
is_homogeneous = 0;
#endif
if (is_homogeneous) {
/* need to receive contiguously into tmp_buf because
displs could make the recvbuf noncontiguous */
MPIR_Type_get_true_extent_impl(recvtype, &recvtype_true_lb, &recvtype_true_extent);
MPID_Ensure_Aint_fits_in_pointer(total_count *
(MPIR_MAX(recvtype_true_extent, recvtype_extent)));
MPIU_CHKLMEM_MALLOC(tmp_buf, void *, total_count*(MPIR_MAX(recvtype_true_extent,recvtype_extent)), mpi_errno, "tmp_buf");
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - recvtype_true_lb);
/* copy local data into right location in tmp_buf */
position = 0;
for (i=0; i<rank; i++) position += recvcounts[i];
if (sendbuf != MPI_IN_PLACE)
{
mpi_errno = MPIR_Localcopy(sendbuf, sendcount, sendtype,
((char *)tmp_buf + position*
recvtype_extent),
recvcounts[rank], recvtype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
else
{
/* if in_place specified, local data is found in recvbuf */
mpi_errno = MPIR_Localcopy(((char *)recvbuf +
displs[rank]*recvtype_extent),
recvcounts[rank], recvtype,
((char *)tmp_buf + position*
recvtype_extent),
recvcounts[rank], recvtype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
curr_cnt = recvcounts[rank];
mask = 0x1;
i = 0;
while (mask < comm_size) {
dst = rank ^ mask;
/* find offset into send and recv buffers. zero out
the least significant "i" bits of rank and dst to
find root of src and dst subtrees. Use ranks of
roots as index to send from and recv into buffer */
dst_tree_root = dst >> i;
dst_tree_root <<= i;
my_tree_root = rank >> i;
my_tree_root <<= i;
if (dst < comm_size) {
send_offset = 0;
for (j=0; j<my_tree_root; j++)
send_offset += recvcounts[j];
recv_offset = 0;
for (j=0; j<dst_tree_root; j++)
recv_offset += recvcounts[j];
mpi_errno = MPIC_Sendrecv(((char *)tmp_buf + send_offset * recvtype_extent),
curr_cnt, recvtype, dst,
MPIR_ALLGATHERV_TAG,
((char *)tmp_buf + recv_offset * recvtype_extent),
total_count - recv_offset, recvtype, dst,
MPIR_ALLGATHERV_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
last_recv_cnt = 0;
} else
/* for convenience, recv is posted for a bigger amount
than will be sent */
MPIR_Get_count_impl(&status, recvtype, &last_recv_cnt);
curr_cnt += last_recv_cnt;
}
/* if some processes in this process's subtree in this step
did not have any destination process to communicate with
because of non-power-of-two, we need to send them the
data that they would normally have received from those
processes. That is, the haves in this subtree must send to
the havenots. We use a logarithmic
recursive-halfing algorithm for this. */
/* This part of the code will not currently be
executed because we are not using recursive
doubling for non power of two. Mark it as experimental
so that it doesn't show up as red in the coverage
tests. */
/* --BEGIN EXPERIMENTAL-- */
if (dst_tree_root + mask > comm_size) {
nprocs_completed = comm_size - my_tree_root - mask;
/* nprocs_completed is the number of processes in this
subtree that have all the data. Send data to others
in a tree fashion. First find root of current tree
that is being divided into two. k is the number of
least-significant bits in this process's rank that
must be zeroed out to find the rank of the root */
j = mask;
k = 0;
while (j) {
j >>= 1;
k++;
}
k--;
tmp_mask = mask >> 1;
while (tmp_mask) {
dst = rank ^ tmp_mask;
tree_root = rank >> k;
tree_root <<= k;
/* send only if this proc has data and destination
doesn't have data. at any step, multiple processes
can send if they have the data */
if ((dst > rank) &&
(rank < tree_root + nprocs_completed)
&& (dst >= tree_root + nprocs_completed)) {
offset = 0;
for (j=0; j<(my_tree_root+mask); j++)
offset += recvcounts[j];
offset *= recvtype_extent;
mpi_errno = MPIC_Send(((char *)tmp_buf + offset),
last_recv_cnt,
recvtype, dst,
MPIR_ALLGATHERV_TAG, comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* last_recv_cnt was set in the previous
receive. that's the amount of data to be
sent now. */
}
/* recv only if this proc. doesn't have data and sender
has data */
else if ((dst < rank) &&
(dst < tree_root + nprocs_completed) &&
(rank >= tree_root + nprocs_completed)) {
offset = 0;
for (j=0; j<(my_tree_root+mask); j++)
offset += recvcounts[j];
mpi_errno = MPIC_Recv(((char *)tmp_buf + offset * recvtype_extent),
total_count - offset, recvtype,
dst, MPIR_ALLGATHERV_TAG,
comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIU_ERR_SET(mpi_errno, *errflag, "**fail");
MPIU_ERR_ADD(mpi_errno_ret, mpi_errno);
last_recv_cnt = 0;
} else
/* for convenience, recv is posted for a
bigger amount than will be sent */
MPIR_Get_count_impl(&status, recvtype, &last_recv_cnt);
curr_cnt += last_recv_cnt;
}
tmp_mask >>= 1;
k--;
}
}
/* --END EXPERIMENTAL-- */
mask <<= 1;
i++;
}
/* copy data from tmp_buf to recvbuf */
position = 0;
for (j=0; j<comm_size; j++) {
if ((sendbuf != MPI_IN_PLACE) || (j != rank)) {
/* not necessary to copy if in_place and
j==rank. otherwise copy. */
mpi_errno = MPIR_Localcopy(((char *)tmp_buf + position*recvtype_extent),
recvcounts[j], recvtype,
((char *)recvbuf + displs[j]*recvtype_extent),
recvcounts[j], recvtype);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
}
position += recvcounts[j];
}
}
int MPIR_Allreduce_intra_recursive_doubling(
const void *sendbuf,
void *recvbuf,
int count,
MPI_Datatype datatype,
MPI_Op op,
MPIR_Comm * comm_ptr,
MPIR_Errflag_t * errflag)
{
MPIR_CHKLMEM_DECL(1);
#ifdef MPID_HAS_HETERO
int is_homogeneous;
int rc;
#endif
int comm_size, rank;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
int mask, dst, is_commutative, pof2, newrank, rem, newdst;
MPI_Aint true_extent, true_lb, extent;
void *tmp_buf;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
is_commutative = MPIR_Op_is_commutative(op);
/* need to allocate temporary buffer to store incoming data*/
MPIR_Type_get_true_extent_impl(datatype, &true_lb, &true_extent);
MPIR_Datatype_get_extent_macro(datatype, extent);
MPIR_Ensure_Aint_fits_in_pointer(count * MPL_MAX(extent, true_extent));
MPIR_CHKLMEM_MALLOC(tmp_buf, void *, count*(MPL_MAX(extent,true_extent)), mpi_errno, "temporary buffer", MPL_MEM_BUFFER);
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - true_lb);
/* copy local data into recvbuf */
if (sendbuf != MPI_IN_PLACE) {
mpi_errno = MPIR_Localcopy(sendbuf, count, datatype, recvbuf,
count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
/* get nearest power-of-two less than or equal to comm_size */
pof2 = comm_ptr->pof2;
rem = comm_size - pof2;
/* In the non-power-of-two case, all even-numbered
processes of rank < 2*rem send their data to
(rank+1). These even-numbered processes no longer
participate in the algorithm until the very end. The
remaining processes form a nice power-of-two. */
if (rank < 2*rem) {
if (rank % 2 == 0) { /* even */
mpi_errno = MPIC_Send(recvbuf, count,
datatype, rank+1,
MPIR_ALLREDUCE_TAG, comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* temporarily set the rank to -1 so that this
process does not pariticipate in recursive
doubling */
newrank = -1;
}
else { /* odd */
mpi_errno = MPIC_Recv(tmp_buf, count,
datatype, rank-1,
MPIR_ALLREDUCE_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* do the reduction on received data. since the
ordering is right, it doesn't matter whether
the operation is commutative or not. */
mpi_errno = MPIR_Reduce_local(tmp_buf, recvbuf, count, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* change the rank */
newrank = rank / 2;
}
}
else /* rank >= 2*rem */
newrank = rank - rem;
/* If op is user-defined or count is less than pof2, use
recursive doubling algorithm. Otherwise do a reduce-scatter
followed by allgather. (If op is user-defined,
derived datatypes are allowed and the user could pass basic
datatypes on one process and derived on another as long as
the type maps are the same. Breaking up derived
datatypes to do the reduce-scatter is tricky, therefore
using recursive doubling in that case.) */
if (newrank != -1) {
mask = 0x1;
while (mask < pof2) {
newdst = newrank ^ mask;
/* find real rank of dest */
dst = (newdst < rem) ? newdst*2 + 1 : newdst + rem;
/* Send the most current data, which is in recvbuf. Recv
into tmp_buf */
mpi_errno = MPIC_Sendrecv(recvbuf, count, datatype,
dst, MPIR_ALLREDUCE_TAG, tmp_buf,
count, datatype, dst,
MPIR_ALLREDUCE_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* tmp_buf contains data received in this step.
recvbuf contains data accumulated so far */
if (is_commutative || (dst < rank)) {
/* op is commutative OR the order is already right */
mpi_errno = MPIR_Reduce_local(tmp_buf, recvbuf, count, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
else {
/* op is noncommutative and the order is not right */
mpi_errno = MPIR_Reduce_local(recvbuf, tmp_buf, count, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* copy result back into recvbuf */
mpi_errno = MPIR_Localcopy(tmp_buf, count, datatype,
recvbuf, count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
mask <<= 1;
}
}
/* In the non-power-of-two case, all odd-numbered
processes of rank < 2*rem send the result to
(rank-1), the ranks who didn't participate above. */
if (rank < 2*rem) {
if (rank % 2) /* odd */
mpi_errno = MPIC_Send(recvbuf, count,
datatype, rank-1,
MPIR_ALLREDUCE_TAG, comm_ptr, errflag);
else /* even */
mpi_errno = MPIC_Recv(recvbuf, count,
datatype, rank+1,
MPIR_ALLREDUCE_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
fn_exit:
MPIR_CHKLMEM_FREEALL();
return mpi_errno;
fn_fail:
goto fn_exit;
}
int MPIR_Allgather_intra_brucks (
const void *sendbuf,
int sendcount,
MPI_Datatype sendtype,
void *recvbuf,
int recvcount,
MPI_Datatype recvtype,
MPIR_Comm *comm_ptr,
MPIR_Errflag_t *errflag )
{
int comm_size, rank;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Aint recvtype_extent;
MPI_Aint recvtype_true_extent, recvbuf_extent, recvtype_true_lb;
int pof2, src, rem;
void *tmp_buf = NULL;
int curr_cnt, dst;
MPIR_CHKLMEM_DECL(1);
if (((sendcount == 0) && (sendbuf != MPI_IN_PLACE)) || (recvcount == 0))
return MPI_SUCCESS;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
MPIR_Datatype_get_extent_macro( recvtype, recvtype_extent );
/* This is the largest offset we add to recvbuf */
MPIR_Ensure_Aint_fits_in_pointer(MPIR_VOID_PTR_CAST_TO_MPI_AINT recvbuf +
(comm_size * recvcount * recvtype_extent));
/* allocate a temporary buffer of the same size as recvbuf. */
/* get true extent of recvtype */
MPIR_Type_get_true_extent_impl(recvtype, &recvtype_true_lb, &recvtype_true_extent);
recvbuf_extent = recvcount * comm_size * (MPL_MAX(recvtype_true_extent, recvtype_extent));
MPIR_CHKLMEM_MALLOC(tmp_buf, void*, recvbuf_extent, mpi_errno, "tmp_buf", MPL_MEM_BUFFER);
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - recvtype_true_lb);
/* copy local data to the top of tmp_buf */
if (sendbuf != MPI_IN_PLACE) {
mpi_errno = MPIR_Localcopy (sendbuf, sendcount, sendtype,
tmp_buf, recvcount, recvtype);
if (mpi_errno) {
MPIR_ERR_POP(mpi_errno);
}
}
else {
mpi_errno = MPIR_Localcopy (((char *)recvbuf +
rank * recvcount * recvtype_extent),
recvcount, recvtype, tmp_buf,
recvcount, recvtype);
if (mpi_errno) {
MPIR_ERR_POP(mpi_errno);
}
}
/* do the first \floor(\lg p) steps */
curr_cnt = recvcount;
pof2 = 1;
while (pof2 <= comm_size/2) {
src = (rank + pof2) % comm_size;
dst = (rank - pof2 + comm_size) % comm_size;
mpi_errno = MPIC_Sendrecv(tmp_buf, curr_cnt, recvtype, dst,
MPIR_ALLGATHER_TAG,
((char *)tmp_buf + curr_cnt*recvtype_extent),
curr_cnt, recvtype,
src, MPIR_ALLGATHER_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
curr_cnt *= 2;
pof2 *= 2;
}
/* if comm_size is not a power of two, one more step is needed */
rem = comm_size - pof2;
if (rem) {
src = (rank + pof2) % comm_size;
dst = (rank - pof2 + comm_size) % comm_size;
mpi_errno = MPIC_Sendrecv(tmp_buf, rem * recvcount, recvtype,
dst, MPIR_ALLGATHER_TAG,
((char *)tmp_buf + curr_cnt*recvtype_extent),
rem * recvcount, recvtype,
src, MPIR_ALLGATHER_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
/* Rotate blocks in tmp_buf down by (rank) blocks and store
* result in recvbuf. */
mpi_errno = MPIR_Localcopy(tmp_buf, (comm_size-rank)*recvcount,
recvtype, (char *) recvbuf + rank*recvcount*recvtype_extent,
(comm_size-rank)*recvcount, recvtype);
if (mpi_errno) {
MPIR_ERR_POP(mpi_errno);
}
if (rank) {
mpi_errno = MPIR_Localcopy((char *) tmp_buf +
(comm_size-rank)*recvcount*recvtype_extent,
rank*recvcount, recvtype, recvbuf,
rank*recvcount, recvtype);
if (mpi_errno) {
MPIR_ERR_POP(mpi_errno);
}
}
fn_exit:
MPIR_CHKLMEM_FREEALL();
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag != MPIR_ERR_NONE)
MPIR_ERR_SET(mpi_errno, *errflag, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
/*
* Recursive Doubling Algorithm:
*
* Restrictions: power-of-two no. of processes
*
* Cost = lgp.alpha + n.((p-1)/p).beta
*
* TODO: On TCP, we may want to use recursive doubling instead of the
* Bruck's algorithm in all cases because of the pairwise-exchange
* property of recursive doubling (see Benson et al paper in Euro
* PVM/MPI 2003).
*/
int MPIR_Allgather_intra_recursive_doubling(const void *sendbuf,
int sendcount,
MPI_Datatype sendtype,
void *recvbuf,
int recvcount,
MPI_Datatype recvtype,
MPIR_Comm * comm_ptr, MPIR_Errflag_t * errflag)
{
int comm_size, rank;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Aint recvtype_extent;
int j, i;
MPI_Aint curr_cnt, last_recv_cnt = 0;
int dst;
MPI_Status status;
int mask, dst_tree_root, my_tree_root,
send_offset, recv_offset, nprocs_completed, k, offset, tmp_mask, tree_root;
if (((sendcount == 0) && (sendbuf != MPI_IN_PLACE)) || (recvcount == 0))
return MPI_SUCCESS;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
#ifdef HAVE_ERROR_CHECKING
/* Currently this algorithm can only handle power-of-2 comm_size.
* Non power-of-2 comm_size is still experimental */
MPIR_Assert(!(comm_size & (comm_size - 1)));
#endif /* HAVE_ERROR_CHECKING */
MPIR_Datatype_get_extent_macro(recvtype, recvtype_extent);
if (sendbuf != MPI_IN_PLACE) {
mpi_errno = MPIR_Localcopy(sendbuf, sendcount, sendtype,
((char *) recvbuf +
rank * recvcount * recvtype_extent), recvcount, recvtype);
if (mpi_errno) {
MPIR_ERR_POP(mpi_errno);
}
}
curr_cnt = recvcount;
mask = 0x1;
i = 0;
while (mask < comm_size) {
dst = rank ^ mask;
/* find offset into send and recv buffers. zero out
* the least significant "i" bits of rank and dst to
* find root of src and dst subtrees. Use ranks of
* roots as index to send from and recv into buffer */
dst_tree_root = dst >> i;
dst_tree_root <<= i;
my_tree_root = rank >> i;
my_tree_root <<= i;
/* FIXME: saving an MPI_Aint into an int */
send_offset = my_tree_root * recvcount * recvtype_extent;
recv_offset = dst_tree_root * recvcount * recvtype_extent;
if (dst < comm_size) {
mpi_errno = MPIC_Sendrecv(((char *) recvbuf + send_offset),
curr_cnt, recvtype, dst,
MPIR_ALLGATHER_TAG,
((char *) recvbuf + recv_offset),
(comm_size - dst_tree_root) * recvcount,
recvtype, dst,
MPIR_ALLGATHER_TAG, comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag =
MPIX_ERR_PROC_FAILED ==
MPIR_ERR_GET_CLASS(mpi_errno) ? MPIR_ERR_PROC_FAILED : MPIR_ERR_OTHER;
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
last_recv_cnt = 0;
} else {
MPIR_Get_count_impl(&status, recvtype, &last_recv_cnt);
}
curr_cnt += last_recv_cnt;
}
/* if some processes in this process's subtree in this step
* did not have any destination process to communicate with
* because of non-power-of-two, we need to send them the
* data that they would normally have received from those
* processes. That is, the haves in this subtree must send to
* the havenots. We use a logarithmic recursive-halfing algorithm
* for this. */
/* This part of the code will not currently be
* executed because we are not using recursive
* doubling for non power of two. Mark it as experimental
* so that it doesn't show up as red in the coverage
* tests. */
/* --BEGIN EXPERIMENTAL-- */
if (dst_tree_root + mask > comm_size) {
nprocs_completed = comm_size - my_tree_root - mask;
/* nprocs_completed is the number of processes in this
* subtree that have all the data. Send data to others
* in a tree fashion. First find root of current tree
* that is being divided into two. k is the number of
* least-significant bits in this process's rank that
* must be zeroed out to find the rank of the root */
j = mask;
k = 0;
while (j) {
j >>= 1;
k++;
}
k--;
/* FIXME: saving an MPI_Aint into an int */
offset = recvcount * (my_tree_root + mask) * recvtype_extent;
tmp_mask = mask >> 1;
while (tmp_mask) {
dst = rank ^ tmp_mask;
tree_root = rank >> k;
tree_root <<= k;
/* send only if this proc has data and destination
* doesn't have data. at any step, multiple processes
* can send if they have the data */
if ((dst > rank) && (rank < tree_root + nprocs_completed)
&& (dst >= tree_root + nprocs_completed)) {
mpi_errno = MPIC_Send(((char *) recvbuf + offset),
last_recv_cnt,
recvtype, dst, MPIR_ALLGATHER_TAG, comm_ptr, errflag);
/* last_recv_cnt was set in the previous
* receive. that's the amount of data to be
* sent now. */
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag =
MPIX_ERR_PROC_FAILED ==
MPIR_ERR_GET_CLASS(mpi_errno) ? MPIR_ERR_PROC_FAILED : MPIR_ERR_OTHER;
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
/* recv only if this proc. doesn't have data and sender
* has data */
else if ((dst < rank) &&
(dst < tree_root + nprocs_completed) &&
(rank >= tree_root + nprocs_completed)) {
mpi_errno = MPIC_Recv(((char *) recvbuf + offset),
(comm_size - (my_tree_root + mask)) * recvcount,
recvtype, dst,
MPIR_ALLGATHER_TAG, comm_ptr, &status, errflag);
/* nprocs_completed is also equal to the
* no. of processes whose data we don't have */
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag =
MPIX_ERR_PROC_FAILED ==
MPIR_ERR_GET_CLASS(mpi_errno) ? MPIR_ERR_PROC_FAILED : MPIR_ERR_OTHER;
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
last_recv_cnt = 0;
} else {
MPIR_Get_count_impl(&status, recvtype, &last_recv_cnt);
}
curr_cnt += last_recv_cnt;
}
tmp_mask >>= 1;
k--;
}
}
/* --END EXPERIMENTAL-- */
mask <<= 1;
i++;
}
int MPIR_Allreduce_intra_reduce_scatter_allgather(
const void *sendbuf,
void *recvbuf,
int count,
MPI_Datatype datatype,
MPI_Op op,
MPIR_Comm * comm_ptr,
MPIR_Errflag_t * errflag)
{
MPIR_CHKLMEM_DECL(3);
#ifdef MPID_HAS_HETERO
int is_homogeneous;
int rc;
#endif
int comm_size, rank;
int mpi_errno = MPI_SUCCESS;
int mpi_errno_ret = MPI_SUCCESS;
int mask, dst, pof2, newrank, rem, newdst, i,
send_idx, recv_idx, last_idx, send_cnt, recv_cnt, *cnts, *disps;
MPI_Aint true_extent, true_lb, extent;
void *tmp_buf;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
/* need to allocate temporary buffer to store incoming data*/
MPIR_Type_get_true_extent_impl(datatype, &true_lb, &true_extent);
MPIR_Datatype_get_extent_macro(datatype, extent);
MPIR_Ensure_Aint_fits_in_pointer(count * MPL_MAX(extent, true_extent));
MPIR_CHKLMEM_MALLOC(tmp_buf, void *, count*(MPL_MAX(extent,true_extent)), mpi_errno, "temporary buffer", MPL_MEM_BUFFER);
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *)((char*)tmp_buf - true_lb);
/* copy local data into recvbuf */
if (sendbuf != MPI_IN_PLACE) {
mpi_errno = MPIR_Localcopy(sendbuf, count, datatype, recvbuf,
count, datatype);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
}
/* get nearest power-of-two less than or equal to comm_size */
pof2 = comm_ptr->pof2;
rem = comm_size - pof2;
/* In the non-power-of-two case, all even-numbered
processes of rank < 2*rem send their data to
(rank+1). These even-numbered processes no longer
participate in the algorithm until the very end. The
remaining processes form a nice power-of-two. */
if (rank < 2*rem) {
if (rank % 2 == 0) { /* even */
mpi_errno = MPIC_Send(recvbuf, count,
datatype, rank+1,
MPIR_ALLREDUCE_TAG, comm_ptr, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* temporarily set the rank to -1 so that this
process does not pariticipate in recursive
doubling */
newrank = -1;
}
else { /* odd */
mpi_errno = MPIC_Recv(tmp_buf, count,
datatype, rank-1,
MPIR_ALLREDUCE_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* do the reduction on received data. since the
ordering is right, it doesn't matter whether
the operation is commutative or not. */
mpi_errno = MPIR_Reduce_local(tmp_buf, recvbuf, count, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* change the rank */
newrank = rank / 2;
}
}
else /* rank >= 2*rem */
newrank = rank - rem;
/* If op is user-defined or count is less than pof2, use
recursive doubling algorithm. Otherwise do a reduce-scatter
followed by allgather. (If op is user-defined,
derived datatypes are allowed and the user could pass basic
datatypes on one process and derived on another as long as
the type maps are the same. Breaking up derived
datatypes to do the reduce-scatter is tricky, therefore
using recursive doubling in that case.) */
#ifdef HAVE_ERROR_CHECKING
MPIR_Assert(HANDLE_GET_KIND(op)==HANDLE_KIND_BUILTIN);
MPIR_Assert(count >= pof2);
#endif /* HAVE_ERROR_CHECKING */
if (newrank != -1) {
MPIR_CHKLMEM_MALLOC(cnts, int *, pof2*sizeof(int), mpi_errno, "counts", MPL_MEM_BUFFER);
MPIR_CHKLMEM_MALLOC(disps, int *, pof2*sizeof(int), mpi_errno, "displacements", MPL_MEM_BUFFER);
for (i=0; i<pof2; i++)
cnts[i] = count/pof2;
if ((count % pof2) > 0) {
for (i=0; i<(count % pof2); i++)
cnts[i] += 1;
}
disps[0] = 0;
for (i=1; i<pof2; i++)
disps[i] = disps[i-1] + cnts[i-1];
mask = 0x1;
send_idx = recv_idx = 0;
last_idx = pof2;
while (mask < pof2) {
newdst = newrank ^ mask;
/* find real rank of dest */
dst = (newdst < rem) ? newdst*2 + 1 : newdst + rem;
send_cnt = recv_cnt = 0;
if (newrank < newdst) {
send_idx = recv_idx + pof2/(mask*2);
for (i=send_idx; i<last_idx; i++)
send_cnt += cnts[i];
for (i=recv_idx; i<send_idx; i++)
recv_cnt += cnts[i];
}
else {
recv_idx = send_idx + pof2/(mask*2);
for (i=send_idx; i<recv_idx; i++)
send_cnt += cnts[i];
for (i=recv_idx; i<last_idx; i++)
recv_cnt += cnts[i];
}
/* Send data from recvbuf. Recv into tmp_buf */
mpi_errno = MPIC_Sendrecv((char *) recvbuf +
disps[send_idx]*extent,
send_cnt, datatype,
dst, MPIR_ALLREDUCE_TAG,
(char *) tmp_buf +
disps[recv_idx]*extent,
recv_cnt, datatype, dst,
MPIR_ALLREDUCE_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
/* tmp_buf contains data received in this step.
recvbuf contains data accumulated so far */
/* This algorithm is used only for predefined ops
and predefined ops are always commutative. */
mpi_errno = MPIR_Reduce_local(((char *) tmp_buf + disps[recv_idx]*extent),
((char *) recvbuf + disps[recv_idx]*extent),
recv_cnt, datatype, op);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* update send_idx for next iteration */
send_idx = recv_idx;
mask <<= 1;
/* update last_idx, but not in last iteration
because the value is needed in the allgather
step below. */
if (mask < pof2)
last_idx = recv_idx + pof2/mask;
}
/* now do the allgather */
mask >>= 1;
while (mask > 0) {
newdst = newrank ^ mask;
/* find real rank of dest */
dst = (newdst < rem) ? newdst*2 + 1 : newdst + rem;
send_cnt = recv_cnt = 0;
if (newrank < newdst) {
/* update last_idx except on first iteration */
if (mask != pof2/2)
last_idx = last_idx + pof2/(mask*2);
recv_idx = send_idx + pof2/(mask*2);
for (i=send_idx; i<recv_idx; i++)
send_cnt += cnts[i];
for (i=recv_idx; i<last_idx; i++)
recv_cnt += cnts[i];
}
else {
recv_idx = send_idx - pof2/(mask*2);
for (i=send_idx; i<last_idx; i++)
send_cnt += cnts[i];
for (i=recv_idx; i<send_idx; i++)
recv_cnt += cnts[i];
}
mpi_errno = MPIC_Sendrecv((char *) recvbuf +
disps[send_idx]*extent,
send_cnt, datatype,
dst, MPIR_ALLREDUCE_TAG,
(char *) recvbuf +
disps[recv_idx]*extent,
recv_cnt, datatype, dst,
MPIR_ALLREDUCE_TAG, comm_ptr,
MPI_STATUS_IGNORE, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag = MPIR_ERR_GET_CLASS(mpi_errno);
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
if (newrank > newdst) send_idx = recv_idx;
mask >>= 1;
}
}
int MPIR_Alltoall_intra_pairwise(const void *sendbuf,
int sendcount,
MPI_Datatype sendtype,
void *recvbuf,
int recvcount,
MPI_Datatype recvtype,
MPIR_Comm * comm_ptr, MPIR_Errflag_t * errflag)
{
int comm_size, i, pof2;
MPI_Aint sendtype_extent, recvtype_extent;
int mpi_errno = MPI_SUCCESS, src, dst, rank;
int mpi_errno_ret = MPI_SUCCESS;
MPI_Status status;
if (recvcount == 0)
return MPI_SUCCESS;
comm_size = comm_ptr->local_size;
rank = comm_ptr->rank;
#ifdef HAVE_ERROR_CHECKING
MPIR_Assert(sendbuf != MPI_IN_PLACE);
#endif /* HAVE_ERROR_CHECKING */
/* Get extent of send and recv types */
MPIR_Datatype_get_extent_macro(recvtype, recvtype_extent);
MPIR_Datatype_get_extent_macro(sendtype, sendtype_extent);
/* Make local copy first */
mpi_errno = MPIR_Localcopy(((char *) sendbuf +
rank * sendcount * sendtype_extent),
sendcount, sendtype,
((char *) recvbuf +
rank * recvcount * recvtype_extent), recvcount, recvtype);
if (mpi_errno) {
MPIR_ERR_POP(mpi_errno);
}
/* Is comm_size a power-of-two? */
i = 1;
while (i < comm_size)
i *= 2;
if (i == comm_size)
pof2 = 1;
else
pof2 = 0;
/* Do the pairwise exchanges */
for (i = 1; i < comm_size; i++) {
if (pof2 == 1) {
/* use exclusive-or algorithm */
src = dst = rank ^ i;
} else {
src = (rank - i + comm_size) % comm_size;
dst = (rank + i) % comm_size;
}
mpi_errno = MPIC_Sendrecv(((char *) sendbuf +
dst * sendcount * sendtype_extent),
sendcount, sendtype, dst,
MPIR_ALLTOALL_TAG,
((char *) recvbuf +
src * recvcount * recvtype_extent),
recvcount, recvtype, src,
MPIR_ALLTOALL_TAG, comm_ptr, &status, errflag);
if (mpi_errno) {
/* for communication errors, just record the error but continue */
*errflag =
MPIX_ERR_PROC_FAILED ==
MPIR_ERR_GET_CLASS(mpi_errno) ? MPIR_ERR_PROC_FAILED : MPIR_ERR_OTHER;
MPIR_ERR_SET(mpi_errno, *errflag, "**fail");
MPIR_ERR_ADD(mpi_errno_ret, mpi_errno);
}
}
fn_exit:
if (mpi_errno_ret)
mpi_errno = mpi_errno_ret;
else if (*errflag != MPIR_ERR_NONE)
MPIR_ERR_SET(mpi_errno, *errflag, "**coll_fail");
return mpi_errno;
fn_fail:
goto fn_exit;
}
