--- /dev/null
+/* Copyright (c) 2014-2016. The SimGrid Team. All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "src/routing/AsClusterTorus.hpp"
+#include "src/surf/network_interface.hpp"
+#include "src/surf/xml/platf.hpp" // FIXME: move that back to the parsing area
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_route_cluster_torus, surf_route_cluster, "Torus Routing part of surf");
+
+inline unsigned int *rankId_to_coords(int rankId, xbt_dynar_t dimensions)
+{
+
+ unsigned int i = 0, cur_dim_size = 1, dim_size_product = 1;
+ unsigned int *coords = (unsigned int *) malloc(xbt_dynar_length(dimensions) * sizeof(unsigned int));
+ for (i = 0; i < xbt_dynar_length(dimensions); i++) {
+ cur_dim_size = xbt_dynar_get_as(dimensions, i, int);
+ coords[i] = (rankId / dim_size_product) % cur_dim_size;
+ dim_size_product *= cur_dim_size;
+ }
+
+ return coords;
+}
+
+
+namespace simgrid {
+ namespace routing {
+ AsClusterTorus::AsClusterTorus(const char*name)
+ : AsCluster(name) {
+ }
+ AsClusterTorus::~AsClusterTorus() {
+ xbt_dynar_free(&dimensions_);
+ }
+
+ void AsClusterTorus::create_links_for_node(sg_platf_cluster_cbarg_t cluster, int id, int rank, int position) {
+ char *link_id;
+ unsigned int j = 0;
+ /*
+ * Create all links that exist in the torus.
+ * Each rank creates @a dimensions-1 links
+ */
+ int neighbour_rank_id = 0; // The other node the link connects
+ int current_dimension = 0, // which dimension are we currently in?
+ // we need to iterate over all dimensions
+ // and create all links there
+ dim_product = 1; // Needed to calculate the next neighbour_id
+ for (j = 0; j < xbt_dynar_length(dimensions_); j++) {
+
+ s_sg_platf_link_cbarg_t link;
+ memset(&link, 0, sizeof(link));
+ current_dimension = xbt_dynar_get_as(dimensions_, j, int);
+ neighbour_rank_id =
+ (((int) rank / dim_product) % current_dimension ==
+ current_dimension - 1) ? rank - (current_dimension - 1) * dim_product : rank + dim_product;
+ //name of neighbor is not right for non contiguous cluster radicals (as id != rank in this case)
+ link_id = bprintf("%s_link_from_%i_to_%i", cluster->id, id, neighbour_rank_id);
+ link.id = link_id;
+ link.bandwidth = cluster->bw;
+ link.latency = cluster->lat;
+ link.policy = cluster->sharing_policy;
+ sg_platf_new_link(&link);
+ s_surf_parsing_link_up_down_t info;
+ if (link.policy == SURF_LINK_FULLDUPLEX) {
+ char *tmp_link = bprintf("%s_UP", link_id);
+ info.linkUp = Link::byName(tmp_link);
+ free(tmp_link);
+ tmp_link = bprintf("%s_DOWN", link_id);
+ info.linkDown = Link::byName(tmp_link);
+ free(tmp_link);
+ } else {
+ info.linkUp = Link::byName(link_id);
+ info.linkDown = info.linkUp;
+ }
+ /*
+ * Add the link to its appropriate position;
+ * note that position rankId*(xbt_dynar_length(dimensions)+has_loopack?+has_limiter?)
+ * holds the link "rankId->rankId"
+ */
+ xbt_dynar_set(privateLinks_, position + j, &info);
+ dim_product *= current_dimension;
+ xbt_free(link_id);
+ }
+ rank++;
+ }
+
+ void AsClusterTorus::parse_specific_arguments(sg_platf_cluster_cbarg_t cluster) {
+
+ unsigned int iter;
+ char *groups;
+ xbt_dynar_t dimensions = xbt_str_split(cluster->topo_parameters, ",");
+
+ if (!xbt_dynar_is_empty(dimensions)) {
+ dimensions_ = xbt_dynar_new(sizeof(int), nullptr);
+ /* We are in a torus cluster
+ * Parse attribute dimensions="dim1,dim2,dim3,...,dimN"
+ * and safe it in a dynarray.
+ * Additionally, we need to know how many ranks we have in total
+ */
+ xbt_dynar_foreach(dimensions, iter, groups) {
+ int tmp = surf_parse_get_int(xbt_dynar_get_as(dimensions, iter, char *));
+ xbt_dynar_set_as(dimensions_, iter, int, tmp);
+ }
+
+ linkCountPerNode_ = xbt_dynar_length(dimensions_);
+
+ }
+ xbt_dynar_free(&dimensions);
+ }
+
+ void AsClusterTorus::getRouteAndLatency(NetCard * src, NetCard * dst, sg_platf_route_cbarg_t route, double *lat) {
+
+ XBT_VERB("torus_get_route_and_latency from '%s'[%d] to '%s'[%d]",
+ src->name(), src->id(), dst->name(), dst->id());
+
+ if (dst->isRouter() || src->isRouter())
+ return;
+
+ if ((src->id() == dst->id()) && hasLoopback_) {
+ s_surf_parsing_link_up_down_t info = xbt_dynar_get_as(privateLinks_, src->id() * linkCountPerNode_, s_surf_parsing_link_up_down_t);
+
+ route->link_list->push_back(info.linkUp);
+ if (lat)
+ *lat += info.linkUp->getLatency();
+ return;
+ }
+
+
+ /*
+ * Dimension based routing routes through each dimension consecutively
+ * TODO Change to dynamic assignment
+ */
+ unsigned int j, cur_dim, dim_product = 1;
+ int current_node = src->id();
+ int unsigned next_node = 0;
+ /*
+ * Arrays that hold the coordinates of the current node and
+ * the target; comparing the values at the i-th position of
+ * both arrays, we can easily assess whether we need to route
+ * into this dimension or not.
+ */
+ unsigned int *myCoords, *targetCoords;
+ myCoords = rankId_to_coords(src->id(), dimensions_);
+ targetCoords = rankId_to_coords(dst->id(), dimensions_);
+ /*
+ * linkOffset describes the offset where the link
+ * we want to use is stored
+ * (+1 is added because each node has a link from itself to itself,
+ * which can only be the case if src->m_id == dst->m_id -- see above
+ * for this special case)
+ */
+ int nodeOffset = (xbt_dynar_length(dimensions_) + 1) * src->id();
+
+ int linkOffset = nodeOffset;
+ bool use_lnk_up = false; // Is this link of the form "cur -> next" or "next -> cur"?
+ // false means: next -> cur
+ while (current_node != dst->id()) {
+ dim_product = 1; // First, we will route in x-dimension
+ for (j = 0; j < xbt_dynar_length(dimensions_); j++) {
+ cur_dim = xbt_dynar_get_as(dimensions_, j, int);
+
+ // current_node/dim_product = position in current dimension
+ if ((current_node / dim_product) % cur_dim != (dst->id() / dim_product) % cur_dim) {
+
+ if ((targetCoords[j] > myCoords[j] && targetCoords[j] <= myCoords[j] + cur_dim / 2) // Is the target node on the right, without the wrap-around?
+ || (myCoords[j] > cur_dim / 2 && (myCoords[j] + cur_dim / 2) % cur_dim >= targetCoords[j])) { // Or do we need to use the wrap around to reach it?
+ if ((current_node / dim_product) % cur_dim == cur_dim - 1)
+ next_node = (current_node + dim_product - dim_product * cur_dim);
+ else
+ next_node = (current_node + dim_product);
+
+ // HERE: We use *CURRENT* node for calculation (as opposed to next_node)
+ nodeOffset = current_node * (linkCountPerNode_);
+ linkOffset = nodeOffset + (hasLoopback_?1:0) + (hasLimiter_?1:0) + j;
+ use_lnk_up = true;
+ assert(linkOffset >= 0);
+ } else { // Route to the left
+ if ((current_node / dim_product) % cur_dim == 0)
+ next_node = (current_node - dim_product + dim_product * cur_dim);
+ else
+ next_node = (current_node - dim_product);
+
+ // HERE: We use *next* node for calculation (as opposed to current_node!)
+ nodeOffset = next_node * (linkCountPerNode_);
+ linkOffset = nodeOffset + j + (hasLoopback_?1:0) + (hasLimiter_?1:0) ;
+ use_lnk_up = false;
+
+ assert(linkOffset >= 0);
+ }
+ XBT_DEBUG("torus_get_route_and_latency - current_node: %i, next_node: %u, linkOffset is %i",
+ current_node, next_node, linkOffset);
+
+ break;
+ }
+
+ dim_product *= cur_dim;
+ }
+
+ s_surf_parsing_link_up_down_t info;
+
+ if (hasLimiter_) { // limiter for sender
+ info = xbt_dynar_get_as(privateLinks_, nodeOffset + hasLoopback_, s_surf_parsing_link_up_down_t);
+ route->link_list->push_back(info.linkUp);
+ }
+
+ info = xbt_dynar_get_as(privateLinks_, linkOffset, s_surf_parsing_link_up_down_t);
+
+ if (use_lnk_up == false) {
+ route->link_list->push_back(info.linkDown);
+ if (lat)
+ *lat += info.linkDown->getLatency();
+ } else {
+ route->link_list->push_back(info.linkUp);
+ if (lat)
+ *lat += info.linkUp->getLatency();
+ }
+ current_node = next_node;
+ next_node = 0;
+ }
+ free(myCoords);
+ free(targetCoords);
+
+ return;
+ }
+
+ }
+}
