1 /* Copyright (c) 2006-2016. 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. */
8 #include "src/surf/AsImpl.hpp"
9 #include "src/surf/network_interface.hpp" // Link FIXME: move to proper header
11 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(AsImpl,surf, "Implementation of S4U autonomous systems");
16 AsImpl::AsImpl(const char *name)
24 xbt_dynar_t AsImpl::getOneLinkRoutes() {
28 /** @brief Get the common ancestor and its first childs in each line leading to src and dst */
29 static void find_common_ancestors(NetCard *src, NetCard *dst,
30 /* OUT */ AsImpl **common_ancestor, AsImpl **src_ancestor, AsImpl **dst_ancestor)
32 #define ROUTING_HIERARCHY_MAXDEPTH 32 /* increase if it is not enough */
33 AsImpl *path_src[ROUTING_HIERARCHY_MAXDEPTH];
34 AsImpl *path_dst[ROUTING_HIERARCHY_MAXDEPTH];
41 /* (1) find the path to root of src and dst*/
42 AsImpl *src_as = src->containingAS();
43 AsImpl *dst_as = dst->containingAS();
45 xbt_assert(src_as, "Host %s must be in an AS", src->name());
46 xbt_assert(dst_as, "Host %s must be in an AS", dst->name());
48 /* (2) find the path to the root routing component */
49 for (AsImpl *current = src_as; current != nullptr; current = static_cast<AsImpl*>(current->father())) {
50 xbt_assert(index_src < ROUTING_HIERARCHY_MAXDEPTH, "ROUTING_HIERARCHY_MAXDEPTH should be increased for element %s", src->name());
51 path_src[index_src++] = current;
53 for (AsImpl *current = dst_as; current != nullptr; current = static_cast<AsImpl*>(current->father())) {
54 xbt_assert(index_dst < ROUTING_HIERARCHY_MAXDEPTH,"ROUTING_HIERARCHY_MAXDEPTH should be increased for path_dst");
55 path_dst[index_dst++] = current;
58 /* (3) find the common father.
59 * Before that, index_src and index_dst may be different, they both point to nullptr in path_src/path_dst
60 * So we move them down simultaneously as long as they point to the same content.
63 current_src = path_src[--index_src];
64 current_dst = path_dst[--index_dst];
65 } while (index_src > 0 && index_dst > 0 && current_src == current_dst);
67 /* (4) if we did not find a difference (index_src or index_dst went to 0), both elements are in the same AS */
68 if (current_src == current_dst)
70 else // we found a difference
71 father = path_src[index_src + 1];
73 /* (5) result generation */
74 *common_ancestor = father; /* the common father of src and dst */
75 *src_ancestor = current_src; /* the first different father of src */
76 *dst_ancestor = current_dst; /* the first different father of dst */
77 #undef ROUTING_HIERARCHY_MAXDEPTH
81 /* PRECONDITION: this is the common ancestor of src and dst */
82 std::vector<surf::Link*> *AsImpl::getBypassRoute(routing::NetCard *src, routing::NetCard *dst)
84 // If never set a bypass route return nullptr without any further computations
85 XBT_DEBUG("generic_get_bypassroute from %s to %s", src->name(), dst->name());
86 if (bypassRoutes_.empty())
89 std::vector<surf::Link*> *bypassedRoute = nullptr;
91 if(dst->containingAS() == this && src->containingAS() == this ){
92 if (bypassRoutes_.find({src->name(),dst->name()}) != bypassRoutes_.end()) {
93 bypassedRoute = bypassRoutes_.at({src->name(),dst->name()});
94 XBT_DEBUG("Found a bypass route with %zu links",bypassedRoute->size());
99 /* (2) find the path to the root routing component */
100 std::vector<As*> path_src;
101 As *current = src->containingAS();
102 while (current != nullptr) {
103 path_src.push_back(current);
104 current = current->father_;
107 std::vector<As*> path_dst;
108 current = dst->containingAS();
109 while (current != nullptr) {
110 path_dst.push_back(current);
111 current = current->father_;
114 /* (3) find the common father */
115 while (path_src.size() > 1 && path_dst.size() >1
116 && path_src.at(path_src.size() -1) == path_dst.at(path_dst.size() -1)) {
121 int max_index_src = path_src.size() - 1;
122 int max_index_dst = path_dst.size() - 1;
124 int max_index = std::max(max_index_src, max_index_dst);
126 for (int max = 0; max <= max_index; max++) {
127 for (int i = 0; i < max; i++) {
128 if (i <= max_index_src && max <= max_index_dst) {
129 const std::pair<std::string, std::string> key = {path_src.at(i)->name(), path_dst.at(max)->name()};
130 if (bypassRoutes_.find(key) != bypassRoutes_.end())
131 bypassedRoute = bypassRoutes_.at(key);
135 if (max <= max_index_src && i <= max_index_dst) {
136 const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(i)->name()};
137 if (bypassRoutes_.find(key) != bypassRoutes_.end())
138 bypassedRoute = bypassRoutes_.at(key);
147 if (max <= max_index_src && max <= max_index_dst) {
148 const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(max)->name()};
149 if (bypassRoutes_.find(key) != bypassRoutes_.end())
150 bypassedRoute = bypassRoutes_.at(key);
156 return bypassedRoute;
160 * \brief Recursive function for getRouteAndLatency
162 * \param src the source host
163 * \param dst the destination host
164 * \param links Where to store the links and the gw information
165 * \param latency If not nullptr, the latency of all links will be added in it
167 void AsImpl::getRouteRecursive(routing::NetCard *src, routing::NetCard *dst,
168 /* OUT */ std::vector<surf::Link*> * links, double *latency)
170 s_sg_platf_route_cbarg_t route;
171 memset(&route,0,sizeof(route));
173 XBT_DEBUG("Solve route/latency \"%s\" to \"%s\"", src->name(), dst->name());
175 /* Find how src and dst are interconnected */
176 AsImpl *common_ancestor, *src_ancestor, *dst_ancestor;
177 find_common_ancestors(src, dst, &common_ancestor, &src_ancestor, &dst_ancestor);
178 XBT_DEBUG("elements_father: common ancestor '%s' src ancestor '%s' dst ancestor '%s'",
179 common_ancestor->name(), src_ancestor->name(), dst_ancestor->name());
181 /* Check whether a direct bypass is defined. If so, use it and bail out */
182 std::vector<surf::Link*> *bypassed_route = common_ancestor->getBypassRoute(src, dst);
183 if (nullptr != bypassed_route) {
184 for (surf::Link *link : *bypassed_route) {
185 links->push_back(link);
187 *latency += link->getLatency();
192 /* If src and dst are in the same AS, life is good */
193 if (src_ancestor == dst_ancestor) { /* SURF_ROUTING_BASE */
194 route.link_list = links;
195 common_ancestor->getRouteAndLatency(src, dst, &route, latency);
199 /* Not in the same AS, no bypass. We'll have to find our path between the ASes recursively*/
201 route.link_list = new std::vector<surf::Link*>();
203 common_ancestor->getRouteAndLatency(src_ancestor->netcard_, dst_ancestor->netcard_, &route, latency);
204 xbt_assert((route.gw_src != nullptr) && (route.gw_dst != nullptr),
205 "bad gateways for route from \"%s\" to \"%s\"", src->name(), dst->name());
207 /* If source gateway is not our source, we have to recursively find our way up to this point */
208 if (src != route.gw_src)
209 getRouteRecursive(src, route.gw_src, links, latency);
210 for (auto link: *route.link_list)
211 links->push_back(link);
212 delete route.link_list;
214 /* If dest gateway is not our destination, we have to recursively find our way from this point */
215 if (route.gw_dst != dst)
216 getRouteRecursive(route.gw_dst, dst, links, latency);