* comment on communicator creation in mca_topo_base_dist_graph_create(...)

* use accesors to retrieve topo info

Author: ggouaillardet

ompi/mca/coll/basic/coll_basic_module.c

@@ -76,29 +76,27 @@ mca_coll_basic_comm_query(struct ompi_communicator_t *comm,
     }
     size *= 2;
     if (OMPI_COMM_IS_CART(comm)) {
-        int cart_size;
-        mca_topo_base_comm_cart_2_2_0_t *cart;
+        int cart_size, ndims;
         assert (NULL != comm->c_topo);
-        cart = comm->c_topo->mtc.cart;
-        cart_size = cart->ndims * 4;
+        comm->c_topo->topo.cart.cartdim_get(comm, &ndims);
+        cart_size = ndims * 4;
         if (cart_size > size) {
             size = cart_size;
         }
     } else if (OMPI_COMM_IS_GRAPH(comm)) {
         int rank, degree;
         assert (NULL != comm->c_topo);
         rank = ompi_comm_rank (comm);
-        mca_topo_base_graph_neighbors_count (comm, rank, &degree);
+        comm->c_topo->topo.graph.graph_neighbors_count (comm, rank, &degree);
         degree *= 2;
         if (degree > size) {
             size = degree;
         }
     } else if (OMPI_COMM_IS_DIST_GRAPH(comm)) {
-        int dist_graph_size;
-        mca_topo_base_comm_dist_graph_2_2_0_t *dist_graph;
+        int dist_graph_size, inneighbors, outneighbors, weighted;
         assert (NULL != comm->c_topo);
-        dist_graph = comm->c_topo->mtc.dist_graph;
-        dist_graph_size = dist_graph->indegree + dist_graph->outdegree;
+        comm->c_topo->topo.dist_graph.dist_graph_neighbors_count(comm, &inneighbors, &outneighbors, &weighted);
+        dist_graph_size = inneighbors + outneighbors;
         if (dist_graph_size > size) {
             size = dist_graph_size;
         }

ompi/mca/topo/base/topo_base_dist_graph_create.c

@@ -287,23 +287,16 @@ int mca_topo_base_dist_graph_create(mca_topo_base_module_t* module,
                                     ompi_communicator_t **newcomm)
 {
     int err;
-
     ompi_proc_t **topo_procs = NULL;
     int num_procs, ret, rank, i;
     ompi_communicator_t *new_comm;
     mca_topo_base_comm_dist_graph_2_2_0_t* topo;
-    num_procs = ompi_comm_size(comm_old);
-    rank = ompi_comm_rank(comm_old);
+
     topo_procs = (ompi_proc_t**)malloc(num_procs * sizeof(ompi_proc_t *));
-    if(OMPI_GROUP_IS_DENSE(comm_old->c_local_group)) {
-        memcpy(topo_procs, 
-               comm_old->c_local_group->grp_proc_pointers,
-               num_procs * sizeof(ompi_proc_t *));
-    } else {
-        for(i = 0 ; i < num_procs; i++) {
-            topo_procs[i] = ompi_group_peer_lookup(comm_old->c_local_group,i);
-        }
+    if (NULL == topo_procs) {
+        return OMPI_ERR_OUT_OF_RESOURCE;
     }
+    num_procs = ompi_comm_size(comm_old);
     new_comm = ompi_comm_allocate(num_procs, 0);
     if (NULL == new_comm) {
         free(topo_procs);
@@ -317,10 +310,22 @@ int mca_topo_base_dist_graph_create(mca_topo_base_module_t* module,
                                               &topo);
     if( OMPI_SUCCESS != err ) {
         free(topo_procs);
-        ompi_comm_free(newcomm);
+        ompi_comm_free(&new_comm);
         return err;
     }
 
+    /* we cannot simply call ompi_comm_create because c_topo
+       must be set before invoking ompi_comm_enable */
+    rank = ompi_comm_rank(comm_old);
+    if(OMPI_GROUP_IS_DENSE(comm_old->c_local_group)) {
+        memcpy(topo_procs, 
+               comm_old->c_local_group->grp_proc_pointers,
+               num_procs * sizeof(ompi_proc_t *));
+    } else {
+        for(i = 0 ; i < num_procs; i++) {
+            topo_procs[i] = ompi_group_peer_lookup(comm_old->c_local_group,i);
+        }
+    }
     assert(NULL == new_comm->c_topo);
     new_comm->c_topo             = module;
     new_comm->c_topo->reorder    = reorder;