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openmpi/opal/util/info_subscriber.h
Mark Allen 482d84b6e5 fixes for Dave's get/set info code
The expected sequence of events for processing info during object creation
is that if there's an incoming info arg, it is opal_info_dup()ed into the obj
at obj->s_info first. Then interested components register callbacks for
keys they want to know about using opal_infosubscribe_infosubscribe().

Inside info_subscribe_subscribe() the specified callback() is called with
whatever matching k/v is in the object's info, or with the default. The
return string from the callback goes into the new k/v stored in info, and
the input k/v is saved as __IN_<key>/<val>. It's saved the same way
whether the input came from info or whether it was a default. A null return
from the callback indicates an ignored key/val, and no k/v is stored for
it, but an __IN_<key>/<val> is still kept so we still have access to the
original.

At MPI_*_set_info() time, opal_infosubscribe_change_info() is used. That
function calls the registered callbacks for each item in the provided info.
If the callback returns non-null, the info is updated with that k/v, or if
the callback returns null, that key is deleted from info. An __IN_<key>/<val>
is saved either way, and overwrites any previously saved value.

When MPI_*_get_info() is called, opal_info_dup_mpistandard() is used, which
allows relatively easy changes in interpretation of the standard, by looking
at both the <key>/<val> and __IN_<key>/<val> in info. Right now it does
  1. includes system extras, eg k/v defaults not expliclty set by the user
  2. omits ignored keys
  3. shows input values, not callback modifications, eg not the internal values

Currently the callbacks are doing things like
    return some_condition ? "true" : "false"
that is, returning static strings that are not to be freed. If the return
strings start becoming more dynamic in the future I don't see how unallocated
strings could support that, so I'd propose a change for the future that
the callback()s registered with info_subscribe_subscribe() do a strdup on
their return, and we change the callers of callback() to free the strings
it returns (there are only two callers).

Rough outline of the smaller changes spread over the less central files:
  comm.c
    initialize comm->super.s_info to NULL
    copy into comm->super.s_info in comm creation calls that provide info
    OBJ_RELEASE comm->super.s_info at free time
  comm_init.c
    initialize comm->super.s_info to NULL
  file.c
    copy into file->super.s_info if file creation provides info
    OBJ_RELEASE file->super.s_info at free time
  win.c
    copy into win->super.s_info if win creation provides info
    OBJ_RELEASE win->super.s_info at free time

  comm_get_info.c
  file_get_info.c
  win_get_info.c
    change_info() if there's no info attached (shouldn't happen if callbacks
      are registered)
    copy the info for the user

The other category of change is generally addressing compiler warnings where
ompi_info_t and opal_info_t were being used a little too interchangably. An
ompi_info_t* contains an opal_info_t*, at &(ompi_info->super)

Also this commit updates the copyrights.

Signed-off-by: Mark Allen <markalle@us.ibm.com>
2017-05-17 01:12:49 -04:00

85 строки
2.8 KiB
C

/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil -*- */
/*
* Copyright (c) 2004-2010 The Trustees of Indiana University and Indiana
* University Research and Technology
* Corporation. All rights reserved.
* Copyright (c) 2004-2007 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) 2007-2012 Cisco Systems, Inc. All rights reserved.
* Copyright (c) 2009 Sun Microsystems, Inc. All rights reserved.
* Copyright (c) 2012-2015 Los Alamos National Security, LLC. All rights
* reserved.
* Copyright (c) 2017 IBM Corporation. All rights reserved.
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
#ifndef OMPI_INFOSUBSCRIBE_H
#define OMPI_INFOSUBSCRIBE_H
#include <string.h>
#include "opal/class/opal_list.h"
#include "opal/class/opal_pointer_array.h"
#include "opal/class/opal_hash_table.h"
#include "opal/threads/mutex.h"
#include "opal/util/info.h"
#include "opal/mca/base/mca_base_var_enum.h"
#define INFO_SUBSCRIBER_SIZE 5
struct opal_infosubscriber_t {
opal_object_t s_base;
opal_hash_table_t s_subscriber_table;
opal_info_t *s_info;
};
typedef struct opal_infosubscriber_t opal_infosubscriber_t;
OPAL_DECLSPEC OBJ_CLASS_DECLARATION(opal_infosubscriber_t);
typedef char*(opal_key_interest_callback_t)(opal_infosubscriber_t*, char*, char*);
/**
* opal_infosubscribe_change_info - Make changes to a Comm/Win/File Info
*
* @param type Comm/Win/File
* @param object corresponding Com/Win/File object
* @param old_info previous info setting
* @param new_info new info setting
*
* @retval OPAL status
*
* Notifies subscribers of info's that have gone away and new info settings
*/
int opal_infosubscribe_change_info(opal_infosubscriber_t*, opal_info_t *);
/**
* opal_infosubscribe_subscribe - Request to be updated about info changes to a Comm/Win/File Info
*
* @param type Comm/Win/File of obj
* @param obj either a comm, win or file
* @param key info key being set
* @param initial_value default value (or NULL if none)
* @param callback callback to be called when key changes
*
* @retval OPAL status
*
* Notifies subscribers of info's that have gone away and new info settings
* Does not try to optimize settings that are the same between old and new
* info's.
*/
int opal_infosubscribe_subscribe(opal_infosubscriber_t*, char *, char *, opal_key_interest_callback_t);
#endif /* OMPI_INFO_H */