1 /* Copyright (c) 2014-2021. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include "simgrid/kernel/routing/TorusZone.hpp"
7 #include "simgrid/kernel/routing/NetPoint.hpp"
8 #include "src/surf/network_interface.hpp"
9 #include "src/surf/xml/platf_private.hpp"
11 #include <boost/algorithm/string/classification.hpp>
12 #include <boost/algorithm/string/split.hpp>
16 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_route_cluster_torus, surf_route_cluster, "Torus Routing part of surf");
22 void TorusZone::create_links_for_node(ClusterCreationArgs* cluster, int id, int rank, unsigned int position)
24 /* Create all links that exist in the torus. Each rank creates @a dimensions-1 links */
25 int dim_product = 1; // Needed to calculate the next neighbor_id
27 for (unsigned int j = 0; j < dimensions_.size(); j++) {
28 LinkCreationArgs link;
29 int current_dimension = dimensions_[j]; // which dimension are we currently in?
30 // we need to iterate over all dimensions and create all links there
31 // The other node the link connects
32 int neighbor_rank_id = ((rank / dim_product) % current_dimension == current_dimension - 1)
33 ? rank - (current_dimension - 1) * dim_product
35 // name of neighbor is not right for non contiguous cluster radicals (as id != rank in this case)
37 std::string(cluster->id) + "_link_from_" + std::to_string(id) + "_to_" + std::to_string(neighbor_rank_id);
39 link.bandwidths.push_back(cluster->bw);
40 link.latency = cluster->lat;
41 link.policy = cluster->sharing_policy;
42 sg_platf_new_link(&link);
43 resource::LinkImpl* linkUp;
44 resource::LinkImpl* linkDown;
45 if (link.policy == s4u::Link::SharingPolicy::SPLITDUPLEX) {
46 linkUp = s4u::Link::by_name(link_id + "_UP")->get_impl();
47 linkDown = s4u::Link::by_name(link_id + "_DOWN")->get_impl();
49 linkUp = s4u::Link::by_name(link_id)->get_impl();
53 * Add the link to its appropriate position.
54 * Note that position rankId*(xbt_dynar_length(dimensions)+has_loopback?+has_limiter?)
55 * holds the link "rankId->rankId"
57 add_private_link_at(position + j, {linkUp, linkDown});
58 dim_product *= current_dimension;
62 void TorusZone::parse_specific_arguments(ClusterCreationArgs* cluster)
64 std::vector<std::string> dimensions;
65 boost::split(dimensions, cluster->topo_parameters, boost::is_any_of(","));
67 if (not dimensions.empty()) {
68 /* We are in a torus cluster
69 * Parse attribute dimensions="dim1,dim2,dim3,...,dimN" and save them into a vector.
70 * Additionally, we need to know how many ranks we have in total
72 for (auto const& group : dimensions)
73 dimensions_.push_back(surf_parse_get_int(group));
75 set_num_links_per_node(dimensions_.size());
79 void TorusZone::get_local_route(NetPoint* src, NetPoint* dst, RouteCreationArgs* route, double* lat)
81 XBT_VERB("torus getLocalRoute from '%s'[%u] to '%s'[%u]", src->get_cname(), src->id(), dst->get_cname(), dst->id());
83 if (dst->is_router() || src->is_router())
86 if (src->id() == dst->id() && has_loopback()) {
87 resource::LinkImpl* uplink = get_uplink_from(node_pos(src->id()));
89 route->link_list.push_back(uplink);
91 *lat += uplink->get_latency();
96 * Dimension based routing routes through each dimension consecutively
97 * TODO Change to dynamic assignment
101 * Arrays that hold the coordinates of the current node and the target; comparing the values at the i-th position of
102 * both arrays, we can easily assess whether we need to route into this dimension or not.
104 const unsigned int dsize = dimensions_.size();
105 std::vector<unsigned int> myCoords(dsize);
106 std::vector<unsigned int> targetCoords(dsize);
107 unsigned int dim_size_product = 1;
108 for (unsigned i = 0; i < dsize; i++) {
109 unsigned cur_dim_size = dimensions_[i];
110 myCoords[i] = (src->id() / dim_size_product) % cur_dim_size;
111 targetCoords[i] = (dst->id() / dim_size_product) % cur_dim_size;
112 dim_size_product *= cur_dim_size;
116 * linkOffset describes the offset where the link we want to use is stored(+1 is added because each node has a link
117 * from itself to itself, which can only be the case if src->m_id == dst->m_id -- see above for this special case)
119 int nodeOffset = (dsize + 1) * src->id();
121 int linkOffset = nodeOffset;
122 bool use_lnk_up = false; // Is this link of the form "cur -> next" or "next -> cur"? false means: next -> cur
123 unsigned int current_node = src->id();
124 while (current_node != dst->id()) {
125 unsigned int next_node = 0;
126 unsigned int dim_product = 1; // First, we will route in x-dimension
127 for (unsigned j = 0; j < dsize; j++) {
128 const unsigned cur_dim = dimensions_[j];
129 // current_node/dim_product = position in current dimension
130 if ((current_node / dim_product) % cur_dim != (dst->id() / dim_product) % cur_dim) {
131 if ((targetCoords[j] > myCoords[j] &&
132 targetCoords[j] <= myCoords[j] + cur_dim / 2) // Is the target node on the right, without the wrap-around?
134 (myCoords[j] > cur_dim / 2 && (myCoords[j] + cur_dim / 2) % cur_dim >=
135 targetCoords[j])) { // Or do we need to use the wrap around to reach it?
136 if ((current_node / dim_product) % cur_dim == cur_dim - 1)
137 next_node = (current_node + dim_product - dim_product * cur_dim);
139 next_node = (current_node + dim_product);
141 // HERE: We use *CURRENT* node for calculation (as opposed to next_node)
142 nodeOffset = node_pos(current_node);
143 linkOffset = node_pos_with_loopback_limiter(current_node) + j;
145 assert(linkOffset >= 0);
146 } else { // Route to the left
147 if ((current_node / dim_product) % cur_dim == 0)
148 next_node = (current_node - dim_product + dim_product * cur_dim);
150 next_node = (current_node - dim_product);
152 // HERE: We use *next* node for calculation (as opposed to current_node!)
153 nodeOffset = node_pos(next_node);
154 linkOffset = node_pos_with_loopback_limiter(next_node) + j;
157 assert(linkOffset >= 0);
159 XBT_DEBUG("torus_get_route_and_latency - current_node: %u, next_node: %u, linkOffset is %i", current_node,
160 next_node, linkOffset);
164 dim_product *= cur_dim;
167 if (has_limiter()) { // limiter for sender
168 route->link_list.push_back(get_uplink_from(node_pos_with_loopback(nodeOffset)));
171 resource::LinkImpl* lnk;
173 lnk = get_uplink_from(linkOffset);
175 lnk = get_downlink_to(linkOffset);
177 route->link_list.push_back(lnk);
179 *lat += lnk->get_latency();
181 current_node = next_node;
184 } // namespace routing
185 } // namespace kernel
186 } // namespace simgrid