NAME

HPL_all_reduce - All reduce operation.

SYNOPSIS

#include "hpl.h"

int HPL_all_reduce( void * BUFFER, const int COUNT, const HPL_T_TYPE DTYPE, const HPL_T_OP OP, MPI_Comm COMM );

HPL_all_reduce performs a global reduce operation across all processes of a group leaving the results on all processes.

BUFFER (local input/global out void *: On entry, BUFFER points to the buffer to be combined. On exit, this array contains the combined data and is identical on all processes in the group.
COUNT (global input) const int: On entry, COUNT indicates the number of entries in BUFFER. COUNT must be at least zero.
DTYPE (global input) const HPL_T_TYPE: On entry, DTYPE specifies the type of the buffers operands.
OP (global input) const HPL_T_OP: On entry, OP is a pointer to the local combine function.
COMM (global/local input) MPI_Comm: The MPI communicator identifying the process collection.