MPI_Win_fence

Perform an MPI fence synchronization on a MPI window

Synopsis

#ifdef ENABLE_QMPI
#ifndef MPICH_MPI_FROM_PMPI
int QMPI_Win_fence(QMPI_Context context, int tool_id, int assert, MPI_Win win) MPICH_API_PUBLIC

Input Parameters

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_fenceoperation. 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 mallocor 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. ierris 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 INTEGERin 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 guarantee 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_ARG: Invalid argument. Some argument is invalid and is not identified by a specific error class (e.g., MPI_ERR_RANK).

MPI_ERR_WIN: Invalid MPI window object

MPI_ERR_OTHER: Other error; use MPI_Error_string to get more information about this error code.