Make MPI_[Comm|File|Win]_get_info MPI 4.0 compliant

So far Open MPI has elected to not hand out values for keys
that were modified through MPI_*_set_info.
MPI 4.0 requires implementations to reflect such changes if the
the new values are supported by the implementation.
Hence, it is sufficient to simply duplicate the info object and
remove the handling of OPAL_INFO_SAVE_PREFIX from OPAL as there
are no other users of this infrastructure.
Signed-off-by: Joseph Schuchart <schuchart@icl.utk.edu>

Author: devreal

ompi/info/info.c

@@ -213,9 +213,6 @@ int ompi_mpiinfo_init(void)
 int ompi_info_dup (ompi_info_t *info, ompi_info_t **newinfo) {
     return opal_info_dup (&(info->super), (opal_info_t **)newinfo);
 }
-int ompi_info_dup_mpistandard (ompi_info_t *info, ompi_info_t **newinfo) {
-    return opal_info_dup_mpistandard (&(info->super), (opal_info_t **)newinfo);
-}
 int ompi_info_set (ompi_info_t *info, const char *key, const char *value) {
     return opal_info_set (&(info->super), key, value);
 }

ompi/mpi/c/comm_get_info.c

@@ -46,9 +46,9 @@ int MPI_Comm_get_info(MPI_Comm comm, MPI_Info *info_used)
     }
 
     if (NULL == comm->super.s_info) {
-/*
- * Setup any defaults if MPI_Win_set_info was never called
- */
+        /*
+        * Setup any defaults if MPI_Win_set_info was never called
+        */
         opal_infosubscribe_change_info(&comm->super, &MPI_INFO_NULL->super);
     }
 
@@ -60,7 +60,7 @@ int MPI_Comm_get_info(MPI_Comm comm, MPI_Info *info_used)
     }
     opal_info_t *opal_info_used = &(*info_used)->super;
 
-    opal_info_dup_mpistandard(comm->super.s_info, &opal_info_used);
+    opal_info_dup(comm->super.s_info, &opal_info_used);
 
     return MPI_SUCCESS;
 }

ompi/mpi/c/file_get_info.c

@@ -70,9 +70,9 @@ int MPI_File_get_info(MPI_File fh, MPI_Info *info_used)
     }
 
     if (NULL == fh->super.s_info) {
-/*
- * Setup any defaults if MPI_Win_set_info was never called
- */
+        /*
+         * Setup any defaults if MPI_Win_set_info was never called
+         */
         opal_infosubscribe_change_info(&fh->super, &MPI_INFO_NULL->super);
     }
 
@@ -83,7 +83,7 @@ int MPI_File_get_info(MPI_File fh, MPI_Info *info_used)
     }
     opal_info_t *opal_info_used = &(*info_used)->super;
 
-    opal_info_dup_mpistandard(fh->super.s_info, &opal_info_used);
+    opal_info_dup(fh->super.s_info, &opal_info_used);
 
     return OMPI_SUCCESS;
 }

ompi/mpi/c/info_set.c

@@ -99,17 +99,6 @@ int MPI_Info_set(MPI_Info info, const char *key, const char *value)
         }
     }
 
-// An extra warning condition is a key that uses our reserved prefix "__IN_".
-// That one is used internally to deal with the dynamic nature the key/val
-// pairs where we have callbacks that modify the val, and the MPI standard
-// wants the get_info call to give back the original setting rather than
-// the callback-modified setting. So if a user directly used a key __IN_foo
-// it would confuse our accounting slightly.
-    if (0 == strncmp(key, OPAL_INFO_SAVE_PREFIX, strlen(OPAL_INFO_SAVE_PREFIX))) {
-        opal_show_help("help-mpi-api.txt", "info-set-with-reserved-prefix", true,
-            key, OPAL_INFO_SAVE_PREFIX);
-    }
-
     /*
      * If all is right with the arguments, then call the back-end
      * allocator.

ompi/mpi/c/win_get_info.c

@@ -48,19 +48,19 @@ int MPI_Win_get_info(MPI_Win win, MPI_Info *info_used)
     }
 
     if (NULL == win->super.s_info) {
-/*
- * Setup any defaults if MPI_Win_set_info was never called
- */
-	opal_infosubscribe_change_info(&win->super, &MPI_INFO_NULL->super); 	
+        /*
+         * Setup any defaults if MPI_Win_set_info was never called
+         */
+        opal_infosubscribe_change_info(&win->super, &MPI_INFO_NULL->super);
     }
 
     (*info_used) = OBJ_NEW(ompi_info_t);
     if (NULL == (*info_used)) {
-       return OMPI_ERRHANDLER_INVOKE(win, MPI_ERR_NO_MEM, FUNC_NAME);
+        return OMPI_ERRHANDLER_INVOKE(win, MPI_ERR_NO_MEM, FUNC_NAME);
     }
     opal_info_t *opal_info_used = &(*info_used)->super;
 
-    ret = opal_info_dup_mpistandard(win->super.s_info, &opal_info_used);
+    ret = opal_info_dup(win->super.s_info, &opal_info_used);
 
     OMPI_ERRHANDLER_RETURN(ret, win, ret, FUNC_NAME);
 }

opal/util/info.c

@@ -3,7 +3,7 @@
  * Copyright (c) 2004-2005 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
+ * Copyright (c) 2004-2021 The University of Tennessee and The University
  *                         of Tennessee Research Foundation.  All rights
  *                         reserved.
  * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
@@ -171,124 +171,6 @@ static int opal_info_set_nolock(opal_info_t *info, const char *key, const char *
     return OPAL_SUCCESS;
 }
 
-/*
- * An object's info can be set, but those settings can be modified by
- * system callbacks. When those callbacks happen, we save a "__IN_<key>"/"val"
- * copy of changed or erased values.
- *
- * extra options for how to dup:
- *   include_system_extras (default 1)
- *   omit_ignored          (default 1)
- *   show_modifications    (default 0)
- */
-static int opal_info_dup_mode(opal_info_t *info, opal_info_t **newinfo,
-                              int include_system_extras, // (k/v with no corresponding __IN_k)
-                              int omit_ignored,          // (__IN_k with no k/v)
-                              int show_modifications)    // (pick v from k/v or __IN_k/v)
-{
-    int err, flag;
-    opal_info_entry_t *iterator;
-
-    const char *pkey;
-    int is_IN_key;
-    int exists_IN_key, exists_reg_key;
-
-    OPAL_THREAD_LOCK(info->i_lock);
-    OPAL_LIST_FOREACH (iterator, &info->super, opal_info_entry_t) {
-        // If we see an __IN_<key> key but no <key>, decide what to do based on mode.
-        // If we see an __IN_<key> and a <key>, skip since it'll be handled when
-        // we process <key>.
-        is_IN_key = 0;
-        exists_IN_key = 0;
-        exists_reg_key = 0;
-        pkey = iterator->ie_key->string;
-        opal_cstring_t *savedval = NULL;
-        opal_cstring_t *valstr = NULL;
-        if (0
-            == strncmp(iterator->ie_key->string, OPAL_INFO_SAVE_PREFIX,
-                       strlen(OPAL_INFO_SAVE_PREFIX))) {
-            pkey += strlen(OPAL_INFO_SAVE_PREFIX);
-
-            is_IN_key = 1;
-            exists_IN_key = 1;
-            opal_info_get_nolock(info, pkey, NULL, &flag);
-            if (flag) {
-                exists_reg_key = 1;
-            }
-        } else {
-            is_IN_key = 0;
-            exists_reg_key = 1;
-
-            // see if there is an __IN_<key> for the current <key>
-            if (strlen(OPAL_INFO_SAVE_PREFIX) + strlen(pkey) < OPAL_MAX_INFO_KEY) {
-                char savedkey[OPAL_MAX_INFO_KEY + 1]; // iterator->ie_key has this as its size
-                snprintf(savedkey, OPAL_MAX_INFO_KEY + 1, OPAL_INFO_SAVE_PREFIX "%s", pkey);
-                // (the prefix macro is a string, so the unreadable part above is a string
-                // concatenation)
-                opal_info_get_nolock(info, savedkey, &savedval, &flag);
-                // release savedval, it remains valid as long we're holding the lock
-                OBJ_RELEASE(savedval);
-                exists_IN_key = 1;
-            } else {
-                flag = 0;
-            }
-        }
-
-        if (is_IN_key) {
-            if (exists_reg_key) {
-                // we're processing __IN_<key> and there exists a <key> so we'll handle it then
-                continue;
-            } else {
-                // we're processing __IN_<key> and no <key> exists
-                // this would mean <key> was set by the user but ignored by the system
-                // so base our behavior on the omit_ignored
-                if (!omit_ignored) {
-                    err = opal_info_set_cstring_nolock(*newinfo, pkey, iterator->ie_value);
-                    if (OPAL_SUCCESS != err) {
-                        OPAL_THREAD_UNLOCK(info->i_lock);
-                        return err;
-                    }
-                }
-            }
-        } else {
-            if (!exists_IN_key) {
-                // we're processing <key> and no __IN_<key> <key> exists
-                // this would mean it's a system setting, not something that came from the user
-                if (include_system_extras) {
-                    valstr = iterator->ie_value;
-                }
-            } else {
-                // we're processing <key> and __IN_<key> also exists
-                // pick which value to use
-                if (!show_modifications) {
-                    valstr = savedval;
-                } else {
-                    valstr = iterator->ie_value;
-                }
-            }
-            if (NULL != valstr) {
-                err = opal_info_set_cstring_nolock(*newinfo, pkey, valstr);
-                /* NOTE: we have not retained valstr so don't release here after using it */
-                if (OPAL_SUCCESS != err) {
-                    OPAL_THREAD_UNLOCK(info->i_lock);
-                    return err;
-                }
-            }
-        }
-    }
-    OPAL_THREAD_UNLOCK(info->i_lock);
-    return OPAL_SUCCESS;
-}
-
-/*
- * Implement opal_info_dup_mpistandard by using whatever mode
- * settings represent our interpretation of the standard
- */
-int opal_info_dup_mpistandard(opal_info_t *info, opal_info_t **newinfo)
-{
-    return opal_info_dup_mode(info, newinfo, 1, 1, 0);
-}
-
 /*
  * Set a value on the info
  */

opal/util/info.h

@@ -105,38 +105,6 @@ int opal_mpiinfo_init(void *);
  */
 int opal_info_dup(opal_info_t *info, opal_info_t **newinfo);
 
-// Comments might still say __IN_<key>, but the code should be using the
-// below macro instead.
-#define OPAL_INFO_SAVE_PREFIX "_OMPI_IN_"
-
-/**
- *   opal_info_dup_mpistandard - Duplicate an 'MPI_Info' object
- *
- *   @param info source info object (handle)
- *   @param newinfo pointer to the new info object (handle)
- *
- *   @retval OPAL_SUCCESS upon success
- *   @retval OPAL_ERR_OUT_OF_RESOURCE if out of memory
- *
- *   The user sets an info object with key/value pairs and once processed,
- *   we keep key/val pairs that might have been modified vs what the user
- *   provided, and some user inputs might have been ignored too.  The original
- *   user inpust are kept as __IN_<key>/<val>.
- *
- *   This routine then outputs key/value pairs as:
- *
- *   if <key> and __IN_<key> both exist:
- *       This means the user set a k/v pair and it was used.
- *       output: <key> / value(__IN_<key>), the original user input
- *   if <key> exists but __IN_<key> doesn't:
- *       This is a system-provided setting.
- *       output: <key>/value(<key>)
- *   if __IN_<key> exists but <key> doesn't:
- *       The user provided a setting that was rejected (ignored) by the system
- *       output: nothing for this key
- */
-int opal_info_dup_mpistandard(opal_info_t *info, opal_info_t **newinfo);
-
 /**
  * Set a new key,value pair on info.
  *