MPI_Win_fence function

Performs an MPI fence synchronization on an MPI window.

Syntax

int MPIAPI MPI_Win_fence(
   int     assert,
   MPI_Win win
);

Parameters

• assert
  Program assertion.

• win
  Window object.

Return value

Returns MPI_SUCCESS on success. Otherwise, the return value is an error code.

In Fortran, the return value is stored in the IERROR parameter.

Fortran

    MPI_WIN_FENCE(ASSERT, WIN, IERROR)
        INTEGER ASSERT, WIN, IERROR

Remarks

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 ORed 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.

Requirements

See also

MPI One-Sided Communications Functions