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)
48 char* link_id = bprintf("%s_link_from_%i_to_%i", cluster->id, id, neighbor_rank_id);
50 link.bandwidth = cluster->bw;
51 link.latency = cluster->lat;
52 link.policy = cluster->sharing_policy;
53 sg_platf_new_link(&link);
54 surf::LinkImpl* linkUp;
55 surf::LinkImpl* linkDown;
56 if (link.policy == SURF_LINK_FULLDUPLEX) {
57 char* tmp_link = bprintf("%s_UP", link_id);
58 linkUp = surf::LinkImpl::byName(tmp_link);
60 tmp_link = bprintf("%s_DOWN", link_id);
61 linkDown = surf::LinkImpl::byName(tmp_link);
64 linkUp = surf::LinkImpl::byName(link_id);
68 * Add the link to its appropriate position;
69 * note that position rankId*(xbt_dynar_length(dimensions)+has_loopback?+has_limiter?)
70 * holds the link "rankId->rankId"
72 privateLinks_.insert({position + j, {linkUp, linkDown}});
73 dim_product *= current_dimension;
79 void TorusZone::parse_specific_arguments(sg_platf_cluster_cbarg_t cluster)
81 std::vector<std::string> dimensions;
82 boost::split(dimensions, cluster->topo_parameters, boost::is_any_of(","));
84 if (not dimensions.empty()) {
85 /* We are in a torus cluster
86 * Parse attribute dimensions="dim1,dim2,dim3,...,dimN" and safe it in a vector.
87 * Additionally, we need to know how many ranks we have in total
89 for (auto group : dimensions) {
90 dimensions_.push_back(surf_parse_get_int(group.c_str()));
93 linkCountPerNode_ = dimensions_.size();
97 void TorusZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cbarg_t route, double* lat)
100 XBT_VERB("torus getLocalRoute from '%s'[%u] to '%s'[%u]", src->name().c_str(), src->id(), dst->name().c_str(),
103 if (dst->isRouter() || src->isRouter())
106 if (src->id() == dst->id() && hasLoopback_) {
107 std::pair<surf::LinkImpl*, surf::LinkImpl*> info = privateLinks_.at(src->id() * linkCountPerNode_);
109 route->link_list->push_back(info.first);
111 *lat += info.first->latency();
116 * Dimension based routing routes through each dimension consecutively
117 * TODO Change to dynamic assignment
119 unsigned int current_node = src->id();
120 unsigned int next_node = 0;
122 * Arrays that hold the coordinates of the current node and
123 * the target; comparing the values at the i-th position of
124 * both arrays, we can easily assess whether we need to route
125 * into this dimension or not.
127 unsigned int myCoords[4];
128 rankId_to_coords(src->id(), dimensions_, &myCoords);
129 unsigned int targetCoords[4];
130 rankId_to_coords(dst->id(), dimensions_, &targetCoords);
132 * linkOffset describes the offset where the link
133 * we want to use is stored
134 * (+1 is added because each node has a link from itself to itself,
135 * which can only be the case if src->m_id == dst->m_id -- see above
136 * for this special case)
138 int nodeOffset = (dimensions_.size() + 1) * src->id();
140 int linkOffset = nodeOffset;
141 bool use_lnk_up = false; // Is this link of the form "cur -> next" or "next -> cur"?
142 // false means: next -> cur
143 while (current_node != dst->id()) {
144 unsigned int dim_product = 1; // First, we will route in x-dimension
146 for (auto cur_dim : dimensions_){
147 // current_node/dim_product = position in current dimension
148 if ((current_node / dim_product) % cur_dim != (dst->id() / dim_product) % cur_dim) {
150 if ((targetCoords[j] > myCoords[j] &&
151 targetCoords[j] <= myCoords[j] + cur_dim / 2) // Is the target node on the right, without the wrap-around?
152 || (myCoords[j] > cur_dim / 2 &&
153 (myCoords[j] + cur_dim / 2) % cur_dim >=
154 targetCoords[j])) { // Or do we need to use the wrap around to reach it?
155 if ((current_node / dim_product) % cur_dim == cur_dim - 1)
156 next_node = (current_node + dim_product - dim_product * cur_dim);
158 next_node = (current_node + dim_product);
160 // HERE: We use *CURRENT* node for calculation (as opposed to next_node)
161 nodeOffset = current_node * (linkCountPerNode_);
162 linkOffset = nodeOffset + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0) + j;
164 assert(linkOffset >= 0);
165 } else { // Route to the left
166 if ((current_node / dim_product) % cur_dim == 0)
167 next_node = (current_node - dim_product + dim_product * cur_dim);
169 next_node = (current_node - dim_product);
171 // HERE: We use *next* node for calculation (as opposed to current_node!)
172 nodeOffset = next_node * (linkCountPerNode_);
173 linkOffset = nodeOffset + j + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0);
176 assert(linkOffset >= 0);
178 XBT_DEBUG("torus_get_route_and_latency - current_node: %u, next_node: %u, linkOffset is %i", current_node,
179 next_node, linkOffset);
184 dim_product *= cur_dim;
187 std::pair<surf::LinkImpl*, surf::LinkImpl*> info;
189 if (hasLimiter_) { // limiter for sender
190 info = privateLinks_.at(nodeOffset + hasLoopback_);
191 route->link_list->push_back(info.first);
194 info = privateLinks_.at(linkOffset);
196 if (use_lnk_up == false) {
197 route->link_list->push_back(info.second);
199 *lat += info.second->latency();
201 route->link_list->push_back(info.first);
203 *lat += info.first->latency();
205 current_node = next_node;