/* comm shrink impl; assumes that standard error checking has already taken
* place in the calling function */
int MPIR_Comm_shrink(MPID_Comm *comm_ptr, MPID_Comm **newcomm_ptr)
{
int mpi_errno = MPI_SUCCESS;
MPID_Group *global_failed, *comm_grp, *new_group_ptr;
int attempts = 0;
int errflag = 0, tmp_errflag = 0;
MPID_MPI_STATE_DECL(MPID_STATE_MPIR_COMM_SHRINK);
MPID_MPI_FUNC_ENTER(MPID_STATE_MPIR_COMM_SHRINK);
/* TODO - Implement this function for intercommunicators */
MPIR_Comm_group_impl(comm_ptr, &comm_grp);
do {
mpi_errno = MPID_Comm_get_all_failed_procs(comm_ptr, &global_failed, MPIR_SHRINK_TAG);
/* Ignore the mpi_errno value here as it will definitely communicate
* with failed procs */
mpi_errno = MPIR_Group_difference_impl(comm_grp, global_failed, &new_group_ptr);
if (mpi_errno) MPIU_ERR_POP(mpi_errno);
if (MPID_Group_empty != global_failed) MPIR_Group_release(global_failed);
mpi_errno = MPIR_Comm_create_group(comm_ptr, new_group_ptr, MPIR_SHRINK_TAG, newcomm_ptr);
errflag = mpi_errno || *newcomm_ptr == NULL;
mpi_errno = MPIR_Allreduce_group(MPI_IN_PLACE, &errflag, 1, MPI_INT, MPI_MAX, comm_ptr,
new_group_ptr, MPIR_SHRINK_TAG, &tmp_errflag);
MPIR_Group_release(new_group_ptr);
if (errflag) MPIU_Object_set_ref(new_group_ptr, 0);
} while (errflag && ++attempts < 5);
if (errflag && attempts >= 5) goto fn_fail;
else mpi_errno = MPI_SUCCESS;
fn_exit:
MPIR_Group_release(comm_grp);
MPID_MPI_FUNC_EXIT(MPID_STATE_MPIR_COMM_SHRINK);
return mpi_errno;
fn_fail:
if (*newcomm_ptr) MPIU_Object_set_ref(*newcomm_ptr, 0);
MPIU_Object_set_ref(global_failed, 0);
MPIU_Object_set_ref(new_group_ptr, 0);
goto fn_exit;
}
int MPIR_Comm_agree(MPIR_Comm *comm_ptr, int *flag)
{
int mpi_errno = MPI_SUCCESS, mpi_errno_tmp = MPI_SUCCESS;
MPIR_Group *comm_grp, *failed_grp, *new_group_ptr, *global_failed;
int result, success = 1;
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
int values[2];
MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPIR_COMM_AGREE);
MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPIR_COMM_AGREE);
MPIR_Comm_group_impl(comm_ptr, &comm_grp);
/* Get the locally known (not acknowledged) group of failed procs */
mpi_errno = MPID_Comm_failure_get_acked(comm_ptr, &failed_grp);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* First decide on the group of failed procs. */
mpi_errno = MPID_Comm_get_all_failed_procs(comm_ptr, &global_failed, MPIR_AGREE_TAG);
if (mpi_errno) errflag = MPIR_ERR_PROC_FAILED;
mpi_errno = MPIR_Group_compare_impl(failed_grp, global_failed, &result);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* Create a subgroup without the failed procs */
mpi_errno = MPIR_Group_difference_impl(comm_grp, global_failed, &new_group_ptr);
if (mpi_errno) MPIR_ERR_POP(mpi_errno);
/* If that group isn't the same as what we think is failed locally, then
* mark it as such. */
if (result == MPI_UNEQUAL || errflag)
success = 0;
/* Do an allreduce to decide whether or not anyone thinks the group
* has changed */
mpi_errno_tmp = MPIR_Allreduce_group(MPI_IN_PLACE, &success, 1, MPI_INT, MPI_MIN, comm_ptr,
new_group_ptr, MPIR_AGREE_TAG, &errflag);
if (!success || errflag || mpi_errno_tmp)
success = 0;
values[0] = success;
values[1] = *flag;
/* Determine both the result of this function (mpi_errno) and the result
* of flag that will be returned to the user. */
MPIR_Allreduce_group(MPI_IN_PLACE, values, 2, MPI_INT, MPI_BAND, comm_ptr,
new_group_ptr, MPIR_AGREE_TAG, &errflag);
/* Ignore the result of the operation this time. Everyone will either
* return a failure because of !success earlier or they will return
* something useful for flag because of this operation. If there was a new
* failure in between the first allreduce and the second one, it's ignored
* here. */
if (failed_grp != MPIR_Group_empty)
MPIR_Group_release(failed_grp);
MPIR_Group_release(new_group_ptr);
MPIR_Group_release(comm_grp);
if (global_failed != MPIR_Group_empty)
MPIR_Group_release(global_failed);
success = values[0];
*flag = values[1];
if (!success) {
MPIR_ERR_SET(mpi_errno_tmp, MPIX_ERR_PROC_FAILED, "**mpix_comm_agree");
MPIR_ERR_ADD(mpi_errno, mpi_errno_tmp);
}
fn_exit:
MPIR_FUNC_TERSE_EXIT(MPID_STATE_MPIR_COMM_AGREE);
return mpi_errno;
fn_fail:
goto fn_exit;
}
/* comm shrink impl; assumes that standard error checking has already taken
* place in the calling function */
int MPIR_Comm_shrink(MPIR_Comm * comm_ptr, MPIR_Comm ** newcomm_ptr)
{
int mpi_errno = MPI_SUCCESS;
MPIR_Group *global_failed = NULL, *comm_grp = NULL, *new_group_ptr = NULL;
int attempts = 0;
MPIR_Errflag_t errflag = MPIR_ERR_NONE;
MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPIR_COMM_SHRINK);
MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPIR_COMM_SHRINK);
/* TODO - Implement this function for intercommunicators */
MPIR_Comm_group_impl(comm_ptr, &comm_grp);
do {
errflag = MPIR_ERR_NONE;
MPID_Comm_get_all_failed_procs(comm_ptr, &global_failed, MPIR_SHRINK_TAG);
/* Ignore the mpi_errno value here as it will definitely communicate
* with failed procs */
mpi_errno = MPIR_Group_difference_impl(comm_grp, global_failed, &new_group_ptr);
if (mpi_errno)
MPIR_ERR_POP(mpi_errno);
if (MPIR_Group_empty != global_failed)
MPIR_Group_release(global_failed);
mpi_errno = MPIR_Comm_create_group(comm_ptr, new_group_ptr, MPIR_SHRINK_TAG, newcomm_ptr);
if (*newcomm_ptr == NULL) {
errflag = MPIR_ERR_PROC_FAILED;
} else if (mpi_errno) {
errflag =
MPIX_ERR_PROC_FAILED ==
MPIR_ERR_GET_CLASS(mpi_errno) ? MPIR_ERR_PROC_FAILED : MPIR_ERR_OTHER;
MPIR_Comm_release(*newcomm_ptr);
}
mpi_errno = MPII_Allreduce_group(MPI_IN_PLACE, &errflag, 1, MPI_INT, MPI_MAX, comm_ptr,
new_group_ptr, MPIR_SHRINK_TAG, &errflag);
MPIR_Group_release(new_group_ptr);
if (errflag) {
if (*newcomm_ptr != NULL && MPIR_Object_get_ref(*newcomm_ptr) > 0) {
MPIR_Object_set_ref(*newcomm_ptr, 1);
MPIR_Comm_release(*newcomm_ptr);
}
if (MPIR_Object_get_ref(new_group_ptr) > 0) {
MPIR_Object_set_ref(new_group_ptr, 1);
MPIR_Group_release(new_group_ptr);
}
}
} while (errflag && ++attempts < 5);
if (errflag && attempts >= 5)
goto fn_fail;
else
mpi_errno = MPI_SUCCESS;
fn_exit:
MPIR_Group_release(comm_grp);
MPIR_FUNC_TERSE_EXIT(MPID_STATE_MPIR_COMM_SHRINK);
return mpi_errno;
fn_fail:
if (*newcomm_ptr)
MPIR_Object_set_ref(*newcomm_ptr, 0);
MPIR_Object_set_ref(global_failed, 0);
MPIR_Object_set_ref(new_group_ptr, 0);
goto fn_exit;
}
