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openmpi/ompi/runtime/ompi_module_exchange.h
Ralph Castain d70e2e8c2b Merge the ORTE devel branch into the main trunk. Details of what this means will be circulated separately.
Remains to be tested to ensure everything came over cleanly, so please continue to withhold commits a little longer

This commit was SVN r17632.
2008-02-28 01:57:57 +00:00

209 строки
8.7 KiB
C

/*
* Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
* University Research and Technology
* Corporation. All rights reserved.
* Copyright (c) 2004-2005 The University of Tennessee and The University
* of Tennessee Research Foundation. All rights
* reserved.
* Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
* University of Stuttgart. All rights reserved.
* Copyright (c) 2004-2005 The Regents of the University of California.
* All rights reserved.
* Copyright (c) 2006-2007 Los Alamos National Security, LLC. All rights
* reserved.
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
/** @file
* Open MPI module-related data transfer mechanism
*
* A system for publishing module-related data for global
* initialization. Known simply as the "modex", this interface
* provides a system for sharing data, particularly data related to
* modules and their availability on the system.
*
* The modex system is tightly integrated into the general run-time
* initialization system and takes advantage of global update periods
* to minimize the amount of network traffic. All updates are also
* stored in the general purpose registry, and can be read at any time
* during the life of the process. Care should be taken to not call
* the blocking receive during the first stage of global
* initialization, as data will not be available the process will
* likely hang.
*
* @note For the purpose of this interface, two components are
* "corresponding" if:
* - they share the same major and minor MCA version number
* - they have the same type name string
* - they share the same major and minor type version number
* - they have the same component name string
* - they share the same major and minor component version number
*/
#ifndef MCA_OMPI_MODULE_EXCHANGE_H
#define MCA_OMPI_MODULE_EXCHANGE_H
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#include "orte/types.h"
struct mca_base_component_t;
struct ompi_proc_t;
BEGIN_C_DECLS
/**
* Send a module-specific buffer to all other corresponding MCA
* modules in peer processes
*
* This function takes a contiguous buffer of network-ordered data
* and makes it available to all other MCA processes during the
* selection process. Modules sent by one source_component can only
* be received by a corresponding module with the same
* component name.
*
* This function is indended to be used during MCA module
* initialization \em before \em selection (the selection process is
* defined differently for each component type). Each module will
* provide a buffer containing meta information and/or parameters
* that it wants to share with its corresponding modules in peer
* processes. This information typically contains location /
* contact information for establishing communication between
* processes (in a manner that is specific to that module). For
* example, a TCP-based module could provide its IP address and TCP
* port where it is waiting on listen(). The peer process receiving
* this buffer can therefore open a socket to the indicated IP
* address and TCP port.
*
* During the selection process, the MCA framework will effectively
* perform an "allgather" operation of all modex buffers; every
* buffer will be available to every peer process (see
* ompi_modex_recv()).
*
* The buffer is copied during the send call and may be modified or
* free()'ed immediately after the return from this function call.
*
* @note Buffer contents is transparent to the MCA framework -- it \em
* must already either be in network order or be in some format that
* peer processes will be able to read it, regardless of pointer sizes
* or endian bias.
*
* @param[in] source_component A pointer to this module's component
* structure
* @param[in] buffer A pointer to the beginning of the buffer to send
* @param[in] size Number of bytes in the buffer
*
* @retval OMPI_SUCCESS On success
* @retval OMPI_ERROR An unspecified error occurred
*/
OMPI_DECLSPEC int ompi_modex_send(struct mca_base_component_t *source_component,
const void *buffer, size_t size);
/**
* Send a buffer to all other corresponding peer process
*
* Similar to ompi_modex_send(), but uses a char* key instead of a
* component name for indexing. All other semantics apply.
*
* @note Buffer contents is transparent to the modex -- it \em must
* already either be in network order or be in some format that peer
* processes will be able to read it, regardless of pointer sizes or
* endian bias.
*
* @param[in] key A unique key for data storage / lookup
* @param[in] buffer A pointer to the beginning of the buffer to send
* @param[in] size Number of bytes in the buffer
*
* @retval OMPI_SUCCESS On success
* @retval OMPI_ERROR An unspecified error occurred
*/
OMPI_DECLSPEC int ompi_modex_send_string(const char* key,
const void *buffer, size_t size);
/**
* Receive a module-specific buffer from a corresponding MCA module
* in a specific peer process
*
* This is the corresponding "get" call to ompi_modex_send().
* After selection, modules can call this function to receive the
* buffer sent by their corresponding module on the process
* source_proc.
*
* If a buffer from a corresponding module is found, buffer will be
* filled with a pointer to a copy of the buffer that was sent by
* the peer process. It is the caller's responsibility to free this
* buffer. The size will be filled in with the total size of the
* buffer.
*
* @note If the modex system has received information from a given
* process, but has not yet received information for the given
* component, ompi_modex_recv() will return no data. This
* can not happen to a process that has gone through the normal
* startup proceedure, but if you believe this can happen with your
* component, you should use ompi_modex_recv_nb() to receive updates
* when the information becomes available.
*
* @param[in] dest_component A pointer to this module's component struct
* @param[in] source_proc Peer process to receive from
* @param[out] buffer A pointer to a (void*) that will be filled
* with a pointer to the received buffer
* @param[out] size Pointer to a size_t that will be filled with
* the number of bytes in the buffer
*
* @retval OMPI_SUCCESS If a corresponding module buffer is found and
* successfully returned to the caller.
* @retval OMPI_ERR_NOT_IMPLEMENTED Modex support is not available in
* this build of Open MPI (systems like the Cray XT)
* @retval OMPI_ERR_OUT_OF_RESOURCE No memory could be allocated for the
* buffer.
*/
OMPI_DECLSPEC int ompi_modex_recv(struct mca_base_component_t *dest_component,
struct ompi_proc_t *source_proc,
void **buffer, size_t *size);
/**
* Receive a buffer from a given peer
*
* Similar to ompi_modex_recv(), but uses a char* key instead of a
* component name for indexing. All other semantics apply.
*
* @note If the modex system has received information from a given
* process, but has not yet received information for the given
* component, ompi_modex_recv_string() will return no data. This can
* not happen to a process that has gone through the normal startup
* proceedure, but if you believe this can happen with your component,
* you should use ompi_modex_recv_string_nb() to receive updates when
* the information becomes available.
*
* @param[in] key A unique key for data storage / lookup
* @param[in] source_proc Peer process to receive from
* @param[out] buffer A pointer to a (void*) that will be filled
* with a pointer to the received buffer
* @param[out] size Pointer to a size_t that will be filled with
* the number of bytes in the buffer
*
* @retval OMPI_SUCCESS If a corresponding module buffer is found and
* successfully returned to the caller.
* @retval OMPI_ERR_NOT_IMPLEMENTED Modex support is not available in
* this build of Open MPI (systems like the Cray XT)
* @retval OMPI_ERR_OUT_OF_RESOURCE No memory could be allocated for the
* buffer.
*/
OMPI_DECLSPEC int ompi_modex_recv_string(const char* key,
struct ompi_proc_t *source_proc,
void **buffer, size_t *size);
END_C_DECLS
#endif /* MCA_OMPI_MODULE_EXCHANGE_H */