1 /* Copyright (c) 2014-2016. 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"
10 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_route_cluster_torus, surf_route_cluster, "Torus Routing part of surf");
12 inline unsigned int* rankId_to_coords(int rankId, std::vector<unsigned int> dimensions)
15 unsigned int dim_size_product = 1;
16 unsigned int* coords = new unsigned int[dimensions.size()];
18 for (auto cur_dim_size: dimensions) {
19 coords[i] = (rankId / dim_size_product) % cur_dim_size;
20 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)
37 * Create all links that exist in the torus.
38 * Each rank creates @a dimensions-1 links
40 int neighbor_rank_id = 0; // The other node the link connects
41 int current_dimension = 0; // which dimension are we currently in?
42 // we need to iterate over all dimensions
43 // and create all links there
44 int dim_product = 1; // Needed to calculate the next neighbor_id
45 for (unsigned int j = 0; j < dimensions_.size(); j++) {
47 LinkCreationArgs link;
48 current_dimension = dimensions_.at(j);
49 neighbor_rank_id = ((static_cast<int>(rank) / dim_product) % current_dimension == current_dimension - 1)
50 ? rank - (current_dimension - 1) * dim_product
52 // name of neighbor is not right for non contiguous cluster radicals (as id != rank in this case)
53 char* link_id = bprintf("%s_link_from_%i_to_%i", cluster->id, id, neighbor_rank_id);
55 link.bandwidth = cluster->bw;
56 link.latency = cluster->lat;
57 link.policy = cluster->sharing_policy;
58 sg_platf_new_link(&link);
59 surf::LinkImpl* linkUp;
60 surf::LinkImpl* linkDown;
61 if (link.policy == SURF_LINK_FULLDUPLEX) {
62 char* tmp_link = bprintf("%s_UP", link_id);
63 linkUp = surf::LinkImpl::byName(tmp_link);
65 tmp_link = bprintf("%s_DOWN", link_id);
66 linkDown = surf::LinkImpl::byName(tmp_link);
69 linkUp = surf::LinkImpl::byName(link_id);
73 * Add the link to its appropriate position;
74 * note that position rankId*(xbt_dynar_length(dimensions)+has_loopback?+has_limiter?)
75 * holds the link "rankId->rankId"
77 privateLinks_.insert({position + j, {linkUp, linkDown}});
78 dim_product *= current_dimension;
84 void TorusZone::parse_specific_arguments(sg_platf_cluster_cbarg_t cluster)
89 xbt_dynar_t dimensions = xbt_str_split(cluster->topo_parameters, ",");
91 if (!xbt_dynar_is_empty(dimensions)) {
92 /* We are in a torus cluster
93 * Parse attribute dimensions="dim1,dim2,dim3,...,dimN"
94 * and safe it in a dynarray.
95 * Additionally, we need to know how many ranks we have in total
97 xbt_dynar_foreach (dimensions, iter, groups) {
98 int tmp = surf_parse_get_int(xbt_dynar_get_as(dimensions, iter, char*));
99 dimensions_.push_back(tmp);
102 linkCountPerNode_ = dimensions_.size();
104 xbt_dynar_free(&dimensions);
107 void TorusZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cbarg_t route, double* lat)
110 XBT_VERB("torus getLocalRoute from '%s'[%d] to '%s'[%d]", src->name().c_str(), src->id(), dst->name().c_str(),
113 if (dst->isRouter() || src->isRouter())
116 if (src->id() == dst->id() && hasLoopback_) {
117 std::pair<surf::LinkImpl*, surf::LinkImpl*> info = privateLinks_.at(src->id() * linkCountPerNode_);
119 route->link_list->push_back(info.first);
121 *lat += info.first->latency();
126 * Dimension based routing routes through each dimension consecutively
127 * TODO Change to dynamic assignment
129 unsigned int dim_product = 1;
130 unsigned int current_node = src->id();
131 unsigned int next_node = 0;
133 * Arrays that hold the coordinates of the current node and
134 * the target; comparing the values at the i-th position of
135 * both arrays, we can easily assess whether we need to route
136 * into this dimension or not.
138 unsigned int* myCoords = rankId_to_coords(src->id(), dimensions_);
139 unsigned int* targetCoords = rankId_to_coords(dst->id(), dimensions_);
141 * linkOffset describes the offset where the link
142 * we want to use is stored
143 * (+1 is added because each node has a link from itself to itself,
144 * which can only be the case if src->m_id == dst->m_id -- see above
145 * for this special case)
147 int nodeOffset = (dimensions_.size() + 1) * src->id();
149 int linkOffset = nodeOffset;
150 bool use_lnk_up = false; // Is this link of the form "cur -> next" or "next -> cur"?
151 // false means: next -> cur
152 while (current_node != dst->id()) {
153 dim_product = 1; // First, we will route in x-dimension
155 for (auto cur_dim : dimensions_){
156 // current_node/dim_product = position in current dimension
157 if ((current_node / dim_product) % cur_dim != (dst->id() / dim_product) % cur_dim) {
159 if ((targetCoords[j] > myCoords[j] &&
160 targetCoords[j] <= myCoords[j] + cur_dim / 2) // Is the target node on the right, without the wrap-around?
161 || (myCoords[j] > cur_dim / 2 &&
162 (myCoords[j] + cur_dim / 2) % cur_dim >=
163 targetCoords[j])) { // Or do we need to use the wrap around to reach it?
164 if ((current_node / dim_product) % cur_dim == cur_dim - 1)
165 next_node = (current_node + dim_product - dim_product * cur_dim);
167 next_node = (current_node + dim_product);
169 // HERE: We use *CURRENT* node for calculation (as opposed to next_node)
170 nodeOffset = current_node * (linkCountPerNode_);
171 linkOffset = nodeOffset + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0) + j;
173 assert(linkOffset >= 0);
174 } else { // Route to the left
175 if ((current_node / dim_product) % cur_dim == 0)
176 next_node = (current_node - dim_product + dim_product * cur_dim);
178 next_node = (current_node - dim_product);
180 // HERE: We use *next* node for calculation (as opposed to current_node!)
181 nodeOffset = next_node * (linkCountPerNode_);
182 linkOffset = nodeOffset + j + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0);
185 assert(linkOffset >= 0);
187 XBT_DEBUG("torus_get_route_and_latency - current_node: %i, next_node: %u, linkOffset is %i", current_node,
188 next_node, linkOffset);
193 dim_product *= cur_dim;
196 std::pair<surf::LinkImpl*, surf::LinkImpl*> info;
198 if (hasLimiter_) { // limiter for sender
199 info = privateLinks_.at(nodeOffset + hasLoopback_);
200 route->link_list->push_back(info.first);
203 info = privateLinks_.at(linkOffset);
205 if (use_lnk_up == false) {
206 route->link_list->push_back(info.second);
208 *lat += info.second->latency();
210 route->link_list->push_back(info.first);
212 *lat += info.first->latency();
214 current_node = next_node;
218 delete[] targetCoords;