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 void rankId_to_coords(int rankId, std::vector<unsigned int> dimensions, unsigned int (*coords)[4])
14 unsigned int dim_size_product = 1;
16 for (auto cur_dim_size: dimensions) {
17 (*coords)[i] = (rankId / dim_size_product) % cur_dim_size;
18 dim_size_product *= cur_dim_size;
26 TorusZone::TorusZone(NetZone* father, const char* name) : ClusterZone(father, name)
30 void TorusZone::create_links_for_node(sg_platf_cluster_cbarg_t cluster, int id, int rank, int position)
33 * Create all links that exist in the torus.
34 * Each rank creates @a dimensions-1 links
36 int neighbor_rank_id = 0; // The other node the link connects
37 int current_dimension = 0; // which dimension are we currently in?
38 // we need to iterate over all dimensions
39 // and create all links there
40 int dim_product = 1; // Needed to calculate the next neighbor_id
41 for (unsigned int j = 0; j < dimensions_.size(); j++) {
43 LinkCreationArgs link;
44 current_dimension = dimensions_.at(j);
45 neighbor_rank_id = ((static_cast<int>(rank) / dim_product) % current_dimension == current_dimension - 1)
46 ? rank - (current_dimension - 1) * dim_product
48 // name of neighbor is not right for non contiguous cluster radicals (as id != rank in this case)
49 char* link_id = bprintf("%s_link_from_%i_to_%i", cluster->id, id, 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 char* tmp_link = bprintf("%s_UP", link_id);
59 linkUp = surf::LinkImpl::byName(tmp_link);
61 tmp_link = bprintf("%s_DOWN", link_id);
62 linkDown = surf::LinkImpl::byName(tmp_link);
65 linkUp = surf::LinkImpl::byName(link_id);
69 * Add the link to its appropriate position;
70 * note that position rankId*(xbt_dynar_length(dimensions)+has_loopback?+has_limiter?)
71 * holds the link "rankId->rankId"
73 privateLinks_.insert({position + j, {linkUp, linkDown}});
74 dim_product *= current_dimension;
80 void TorusZone::parse_specific_arguments(sg_platf_cluster_cbarg_t cluster)
85 xbt_dynar_t dimensions = xbt_str_split(cluster->topo_parameters, ",");
87 if (!xbt_dynar_is_empty(dimensions)) {
88 /* We are in a torus cluster
89 * Parse attribute dimensions="dim1,dim2,dim3,...,dimN" and safe it in a vector.
90 * Additionally, we need to know how many ranks we have in total
92 xbt_dynar_foreach (dimensions, iter, groups) {
93 dimensions_.push_back(surf_parse_get_int(groups));
96 linkCountPerNode_ = dimensions_.size();
98 xbt_dynar_free(&dimensions);
101 void TorusZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cbarg_t route, double* lat)
104 XBT_VERB("torus getLocalRoute from '%s'[%d] to '%s'[%d]", src->name().c_str(), src->id(), dst->name().c_str(),
107 if (dst->isRouter() || src->isRouter())
110 if (src->id() == dst->id() && hasLoopback_) {
111 std::pair<surf::LinkImpl*, surf::LinkImpl*> info = privateLinks_.at(src->id() * linkCountPerNode_);
113 route->link_list->push_back(info.first);
115 *lat += info.first->latency();
120 * Dimension based routing routes through each dimension consecutively
121 * TODO Change to dynamic assignment
123 unsigned int dim_product = 1;
124 unsigned int current_node = src->id();
125 unsigned int next_node = 0;
127 * Arrays that hold the coordinates of the current node and
128 * the target; comparing the values at the i-th position of
129 * both arrays, we can easily assess whether we need to route
130 * into this dimension or not.
132 unsigned int myCoords[4];
133 rankId_to_coords(src->id(), dimensions_, &myCoords);
134 unsigned int targetCoords[4];
135 rankId_to_coords(dst->id(), dimensions_, &targetCoords);
137 * linkOffset describes the offset where the link
138 * we want to use is stored
139 * (+1 is added because each node has a link from itself to itself,
140 * which can only be the case if src->m_id == dst->m_id -- see above
141 * for this special case)
143 int nodeOffset = (dimensions_.size() + 1) * src->id();
145 int linkOffset = nodeOffset;
146 bool use_lnk_up = false; // Is this link of the form "cur -> next" or "next -> cur"?
147 // false means: next -> cur
148 while (current_node != dst->id()) {
149 dim_product = 1; // First, we will route in x-dimension
151 for (auto cur_dim : dimensions_){
152 // current_node/dim_product = position in current dimension
153 if ((current_node / dim_product) % cur_dim != (dst->id() / dim_product) % cur_dim) {
155 if ((targetCoords[j] > myCoords[j] &&
156 targetCoords[j] <= myCoords[j] + cur_dim / 2) // Is the target node on the right, without the wrap-around?
157 || (myCoords[j] > cur_dim / 2 &&
158 (myCoords[j] + cur_dim / 2) % cur_dim >=
159 targetCoords[j])) { // Or do we need to use the wrap around to reach it?
160 if ((current_node / dim_product) % cur_dim == cur_dim - 1)
161 next_node = (current_node + dim_product - dim_product * cur_dim);
163 next_node = (current_node + dim_product);
165 // HERE: We use *CURRENT* node for calculation (as opposed to next_node)
166 nodeOffset = current_node * (linkCountPerNode_);
167 linkOffset = nodeOffset + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0) + j;
169 assert(linkOffset >= 0);
170 } else { // Route to the left
171 if ((current_node / dim_product) % cur_dim == 0)
172 next_node = (current_node - dim_product + dim_product * cur_dim);
174 next_node = (current_node - dim_product);
176 // HERE: We use *next* node for calculation (as opposed to current_node!)
177 nodeOffset = next_node * (linkCountPerNode_);
178 linkOffset = nodeOffset + j + (hasLoopback_ ? 1 : 0) + (hasLimiter_ ? 1 : 0);
181 assert(linkOffset >= 0);
183 XBT_DEBUG("torus_get_route_and_latency - current_node: %i, next_node: %u, linkOffset is %i", current_node,
184 next_node, linkOffset);
189 dim_product *= cur_dim;
192 std::pair<surf::LinkImpl*, surf::LinkImpl*> info;
194 if (hasLimiter_) { // limiter for sender
195 info = privateLinks_.at(nodeOffset + hasLoopback_);
196 route->link_list->push_back(info.first);
199 info = privateLinks_.at(linkOffset);
201 if (use_lnk_up == false) {
202 route->link_list->push_back(info.second);
204 *lat += info.second->latency();
206 route->link_list->push_back(info.first);
208 *lat += info.first->latency();
210 current_node = next_node;