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openmpi/ompi/mca/osc/rdma/osc_rdma_passive_target.h
Nathan Hjelm d8df9d414d osc/rdma: add true RDMA one-sided component
This commit adds support for performing one-sided operations over
supported hardware (currently Infiniband and Cray Gemini/Aries). This
component is still undergoing active development.

Current features:

 - Use network atomic operations (fadd, cswap) for implementing
   locking and PSCW synchronization.

 - Aggregate small contiguous puts.

 - Reduced memory footprint by storing window data (pointer, keys,
   etc) at the lowest rank on each node. The data is fetched as each
   process needs to communicate with a new peer. This is a trade-off
   between the performance of the first operation on a peer and the
   memory utilization of a window.

TODO:

 - Add support for the accumulate_ops info key. If it is known that
   the same op or same op/no op is used it may be possible to use
   hardware atomics for fetch-and-op and compare-and-swap.

Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
2015-09-16 15:01:33 -06:00

132 строки
3.8 KiB
C

/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil -*- */
/*
* Copyright (c) 2014-2015 Los Alamos National Security, LLC. All rights
* reserved.
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
#if !defined(OSC_RDMA_PASSIVE_TARGET_H)
#define OSC_RDMA_PASSIVE_TARGET_H
#include "osc_rdma.h"
#include "osc_rdma_sync.h"
#include "osc_rdma_lock.h"
/**
* @brief lock the target in the window using network/cpu atomics
*
* @param[in] lock_type mpi lock type (MPI_LOCK_SHARED, MPI_LOCK_EXCLUSIVE)
* @param[in] target target process
* @param[in] assert asserts
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if there is a conflicting RMA epoch
*/
int ompi_osc_rdma_lock_atomic (int lock_type, int target, int assert, ompi_win_t *win);
/**
* @brief unlock the target in the window using network/cpu atomics
*
* @param[in] target target process
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if the target is not locked
*/
int ompi_osc_rdma_unlock_atomic (int target, ompi_win_t *win);
/**
* @brief lock all targets in window using network/cpu atomics
*
* @param[in] assert asserts
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if there is a conflicting RMA epoch
*/
int ompi_osc_rdma_lock_all_atomic (int assert, struct ompi_win_t *win);
/**
* @brief unlock all targets in window using network/cpu atomics
*
* @param[in] assert asserts
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if the window is not in a lock all access epoch
*/
int ompi_osc_rdma_unlock_all_atomic (struct ompi_win_t *win);
/**
* @brief synchronize the public and private copies of the window
*
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
*
* Just acts as a memory barrier since this module only supports a unified memory
* model.
*/
int ompi_osc_rdma_sync (struct ompi_win_t *win);
/**
* @brief flush rdma transactions to a target
*
* @param[in] target target process
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if the target is not locked
*/
int ompi_osc_rdma_flush (int target, struct ompi_win_t *win);
/**
* @brief flush rdma transactions to all target(s)
*
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if no processes are locked
*
* osc/rdma does not make a distinction between local and remote rma
* completion. this could change in a future release as small messages
* may be internally buffered.
*/
int ompi_osc_rdma_flush_all (struct ompi_win_t *win);
/**
* @brief flush rdma transactions to a target (local completion)
*
* @param[in] target target process
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if the target is not locked
*
* osc/rdma does not make a distinction between local and remote rma
* completion. this could change in a future release as small messages
* may be internally buffered.
*/
int ompi_osc_rdma_flush_local (int target, struct ompi_win_t *win);
/**
* @brief flush rdma transactions to all target(s) (local completion)
*
* @param[in] win mpi window
*
* @returns OMPI_SUCCESS on success
* @returns OMPI_ERR_RMA_SYNC if no processes are locked
*
* osc/rdma does not make a distinction between local and remote rma
* completion. this could change in a future release as small messages
* may be internally buffered.
*/
int ompi_osc_rdma_flush_local_all (struct ompi_win_t *win);
#endif