NAME¶
MPI_Win_fence - Perform an MPI fence synchronization on a MPI window
SYNOPSIS¶
int MPI_Win_fence(int assert, MPI_Win win)
- assert
- - program assertion (integer)
- win
- - window object (handle)
NOTES¶
The
assert argument is used to indicate special conditions for the fence
that an implementation may use to optimize the
MPI_Win_fence operation.
The value zero is always correct. Other assertion values may be or'ed
together. Assertions that are valid for
MPI_Win_fence are:
- MPI_MODE_NOSTORE
- - the local window was not updated by local stores (or local get or
receive calls) since last synchronization.
- MPI_MODE_NOPUT
- - the local window will not be updated by put or accumulate calls after
the fence call, until the ensuing (fence) synchronization.
- MPI_MODE_NOPRECEDE
- - the fence does not complete any sequence of locally issued RMA calls. If
this assertion is given by any process in the window group, then it must
be given by all processes in the group.
- MPI_MODE_NOSUCCEED
- - the fence does not start any sequence of locally issued RMA calls. If
the assertion is given by any process in the window group, then it must be
given by all processes in the group.
THREAD AND INTERRUPT SAFETY¶
This routine is thread-safe. This means that this routine may be safely used by
multiple threads without the need for any user-provided thread locks. However,
the routine is not interrupt safe. Typically, this is due to the use of memory
allocation routines such as
malloc or other non-MPICH runtime routines
that are themselves not interrupt-safe.
NOTES FOR FORTRAN¶
All MPI routines in Fortran (except for
MPI_WTIME and
MPI_WTICK )
have an additional argument
ierr at the end of the argument list.
ierr is an integer and has the same meaning as the return value of the
routine in C. In Fortran, MPI routines are subroutines, and are invoked with
the
call statement.
All MPI objects (e.g.,
MPI_Datatype ,
MPI_Comm ) are of type
INTEGER in Fortran.
ERRORS¶
All MPI routines (except
MPI_Wtime and
MPI_Wtick ) return an error
value; C routines as the value of the function and Fortran routines in the
last argument. Before the value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job. The error handler
may be changed with
MPI_Comm_set_errhandler (for communicators),
MPI_File_set_errhandler (for files), and
MPI_Win_set_errhandler
(for RMA windows). The MPI-1 routine
MPI_Errhandler_set may be used but
its use is deprecated. The predefined error handler
MPI_ERRORS_RETURN
may be used to cause error values to be returned. Note that MPI does
not guarentee that an MPI program can continue past an error; however,
MPI implementations will attempt to continue whenever possible.
- MPI_SUCCESS
- - No error; MPI routine completed successfully.
- MPI_ERR_OTHER
- - Other error; use MPI_Error_string to get more information about
this error code.
- MPI_ERR_WIN
- - Invalid MPI window object
LOCATION¶
/tmp/gyCYfBi4J6/mpich-3.1/src/mpi/rma/win_fence.c