HPL_all_reduce - All reduce operation.
int HPL_all_reduce( void * BUFFER
, const int
, const HPL_T_TYPE DTYPE
, const HPL_T_OP
, MPI_Comm COMM );
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
- 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.