1 /* Copyright (c) 2014-2017. 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 "src/kernel/routing/TorusZone.hpp"
7 #include "src/kernel/routing/NetPoint.hpp"
8 #include "src/surf/network_interface.hpp"
9 #include <boost/algorithm/string/classification.hpp>
10 #include <boost/algorithm/string/split.hpp>
14 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_route_cluster_torus, surf_route_cluster, "Torus Routing part of surf");
16 inline void rankId_to_coords(int rankId, std::vector<unsigned int> dimensions, unsigned int (*coords)[4])
18 unsigned int dim_size_product = 1;
20 for (auto cur_dim_size: dimensions) {
21 (*coords)[i] = (rankId / dim_size_product) % cur_dim_size;
22 dim_size_product *= cur_dim_size;
30 TorusZone::TorusZone(NetZone* father, const char* name) : ClusterZone(father, name)
34 void TorusZone::create_links_for_node(sg_platf_cluster_cbarg_t cluster, int id, int rank, int position)
36 /* Create all links that exist in the torus. Each rank creates @a dimensions-1 links */
37 int dim_product = 1; // Needed to calculate the next neighbor_id
39 for (unsigned int j = 0; j < dimensions_.size(); j++) {
40 LinkCreationArgs link;
41 int current_dimension = dimensions_.at(j); // which dimension are we currently in?
42 // we need to iterate over all dimensions and create all links there
43 // The other node the link connects
44 int neighbor_rank_id = ((static_cast<int>(rank) / dim_product) % current_dimension == current_dimension - 1)
45 ? rank - (current_dimension - 1) * dim_product
47 // name of neighbor is not right for non contiguous cluster radicals (as id != rank in this case)
49 std::string(cluster->id) + "_link_from_" + std::to_string(id) + "_to_" + std::to_string(neighbor_rank_id);
51 link.bandwidth = cluster->bw;
52 link.latency = cluster->lat;
53 link.policy = cluster->sharing_policy;
54 sg_platf_new_link(&link);
55 surf::LinkImpl* linkUp;
56 surf::LinkImpl* linkDown;
57 if (link.policy == SURF_LINK_FULLDUPLEX) {
58 std::string tmp_link = link_id + "_UP";
59 linkUp = surf::LinkImpl::byName(tmp_link);
60 tmp_link = link_id + "_DOWN";
61 linkDown = surf::LinkImpl::byName(tmp_link);
63 linkUp = surf::LinkImpl::byName(link_id);
67 * Add the link to its appropriate position;
68 * note that position rankId*(xbt_dynar_length(dimensions)+has_loopback?+has_limiter?)
69 * holds the link "rankId->rankId"
71 privateLinks_.insert({position + j, {linkUp, linkDown}});
72 dim_product *= current_dimension;
77 void TorusZone::parse_specific_arguments(sg_platf_cluster_cbarg_t cluster)
79 std::vector<std::string> dimensions;
80 boost::split(dimensions, cluster->topo_parameters, boost::is_any_of(","));
82 if (not dimensions.empty()) {
83 /* We are in a torus cluster
84 * Parse attribute dimensions="dim1,dim2,dim3,...,dimN" and safe it in a vector.
85 * Additionally, we need to know how many ranks we have in total
87 for (auto group : dimensions) {
88 dimensions_.push_back(surf_parse_get_int(group.c_str()));
91 linkCountPerNode_ = dimensions_.size();
95 void TorusZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cbarg_t route, double* lat)
98 XBT_VERB("torus getLocalRoute from '%s'[%u] to '%s'[%u]", src->name().c_str(), src->id(), dst->name().c_str(),
101 if (dst->isRouter() || src->isRouter())
104 if (src->id() == dst->id() && hasLoopback_) {
105 std::pair<surf::LinkImpl*, surf::LinkImpl*> info = privateLinks_.at(src->id() * linkCountPerNode_);
107 route->link_list->push_back(info.first);
109 *lat += info.first->latency();
114 * Dimension based routing routes through each dimension consecutively
115 * TODO Change to dynamic assignment
117 unsigned int current_node = src->id();
118 unsigned int next_node = 0;
120 * Arrays that hold the coordinates of the current node and
121 * the target; comparing the values at the i-th position of
122 * both arrays, we can easily assess whether we need to route
123 * into this dimension or not.
125 unsigned int myCoords[4];
126 rankId_to_coords(src->id(), dimensions_, &myCoords);
127 unsigned int targetCoords[4];
128 rankId_to_coords(dst->id(), dimensions_, &targetCoords);
130 * linkOffset describes the offset where the link
131 * we want to use is stored
132 * (+1 is added because each node has a link from itself to itself,
133 * which can only be the case if src->m_id == dst->m_id -- see above
134 * for this special case)
136 int nodeOffset = (dimensions_.size() + 1) * src->id();
138 int linkOffset = nodeOffset;
139 bool use_lnk_up = false; // Is this link of the form "cur -> next" or "next -> cur"?
140 // false means: next -> cur
141 while (current_node != dst->id()) {
142 unsigned int dim_product = 1; // First, we will route in x-dimension
144 for (auto cur_dim : dimensions_){
145 // current_node/dim_product = position in current dimension
146 if ((current_node / dim_product) % cur_dim != (dst->id() / dim_product) % cur_dim) {
148 if ((targetCoords[j] > myCoords[j] &&
149 targetCoords[j] <= myCoords[j] + cur_dim / 2) // Is the target node on the right, without the wrap-around?
150 || (myCoords[j] > cur_dim / 2 &&
151 (myCoords[j] + cur_dim / 2) % cur_dim >=
152 targetCoords[j])) { // Or do we need to use the wrap around to reach it?
153 if ((current_node / dim_product) % cur_dim == cur_dim - 1)
154 next_node = (current_node + dim_product - dim_product * cur_dim);
156 next_node = (current_node + dim_product);
158 // HERE: We use *CURRENT* node for calculation (as opposed to next_node)
159 nodeOffset = current_node * (linkCountPerNode_);
160 linkOffset = nodeOffset + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0) + j;
162 assert(linkOffset >= 0);
163 } else { // Route to the left
164 if ((current_node / dim_product) % cur_dim == 0)
165 next_node = (current_node - dim_product + dim_product * cur_dim);
167 next_node = (current_node - dim_product);
169 // HERE: We use *next* node for calculation (as opposed to current_node!)
170 nodeOffset = next_node * (linkCountPerNode_);
171 linkOffset = nodeOffset + j + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0);
174 assert(linkOffset >= 0);
176 XBT_DEBUG("torus_get_route_and_latency - current_node: %u, next_node: %u, linkOffset is %i", current_node,
177 next_node, linkOffset);
182 dim_product *= cur_dim;
185 std::pair<surf::LinkImpl*, surf::LinkImpl*> info;
187 if (hasLimiter_) { // limiter for sender
188 info = privateLinks_.at(nodeOffset + hasLoopback_);
189 route->link_list->push_back(info.first);
192 info = privateLinks_.at(linkOffset);
194 if (use_lnk_up == false) {
195 route->link_list->push_back(info.second);
197 *lat += info.second->latency();
199 route->link_list->push_back(info.first);
201 *lat += info.first->latency();
203 current_node = next_node;