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/kernel/routing/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");
17 AsImpl::AsImpl(As* father, const char* name) : As(father, name)
19 xbt_assert(nullptr == xbt_lib_get_or_null(as_router_lib, name, ROUTING_ASR_LEVEL),
20 "Refusing to create a second AS called \"%s\".", name);
22 netcard_ = new simgrid::kernel::routing::NetCardImpl(name, simgrid::kernel::routing::NetCard::Type::As,
23 static_cast<AsImpl*>(father));
24 xbt_lib_set(as_router_lib, name, ROUTING_ASR_LEVEL, (void*)netcard_);
25 XBT_DEBUG("Having set name '%s' id '%d'", name, netcard_->id());
27 AsImpl::~AsImpl() = default;
29 xbt_dynar_t AsImpl::getOneLinkRoutes()
34 /** @brief Get the common ancestor and its first childs in each line leading to src and dst */
35 static void find_common_ancestors(NetCard *src, NetCard *dst,
36 /* OUT */ AsImpl **common_ancestor, AsImpl **src_ancestor, AsImpl **dst_ancestor)
38 #define ROUTING_HIERARCHY_MAXDEPTH 32 /* increase if it is not enough */
39 AsImpl *path_src[ROUTING_HIERARCHY_MAXDEPTH];
40 AsImpl *path_dst[ROUTING_HIERARCHY_MAXDEPTH];
47 /* (1) find the path to root of src and dst*/
48 AsImpl *src_as = src->containingAS();
49 AsImpl *dst_as = dst->containingAS();
51 xbt_assert(src_as, "Host %s must be in an AS", src->name());
52 xbt_assert(dst_as, "Host %s must be in an AS", dst->name());
54 /* (2) find the path to the root routing component */
55 for (AsImpl *current = src_as; current != nullptr; current = static_cast<AsImpl*>(current->father())) {
56 xbt_assert(index_src < ROUTING_HIERARCHY_MAXDEPTH, "ROUTING_HIERARCHY_MAXDEPTH should be increased for element %s", src->name());
57 path_src[index_src++] = current;
59 for (AsImpl *current = dst_as; current != nullptr; current = static_cast<AsImpl*>(current->father())) {
60 xbt_assert(index_dst < ROUTING_HIERARCHY_MAXDEPTH,"ROUTING_HIERARCHY_MAXDEPTH should be increased for path_dst");
61 path_dst[index_dst++] = current;
64 /* (3) find the common father.
65 * Before that, index_src and index_dst may be different, they both point to nullptr in path_src/path_dst
66 * So we move them down simultaneously as long as they point to the same content.
69 current_src = path_src[--index_src];
70 current_dst = path_dst[--index_dst];
71 } while (index_src > 0 && index_dst > 0 && current_src == current_dst);
73 /* (4) if we did not find a difference (index_src or index_dst went to 0), both elements are in the same AS */
74 if (current_src == current_dst)
76 else // we found a difference
77 father = path_src[index_src + 1];
79 /* (5) result generation */
80 *common_ancestor = father; /* the common father of src and dst */
81 *src_ancestor = current_src; /* the first different father of src */
82 *dst_ancestor = current_dst; /* the first different father of dst */
83 #undef ROUTING_HIERARCHY_MAXDEPTH
87 /* PRECONDITION: this is the common ancestor of src and dst */
88 std::vector<surf::Link*> *AsImpl::getBypassRoute(routing::NetCard *src, routing::NetCard *dst)
90 // If never set a bypass route return nullptr without any further computations
91 XBT_DEBUG("generic_get_bypassroute from %s to %s", src->name(), dst->name());
92 if (bypassRoutes_.empty())
95 std::vector<surf::Link*> *bypassedRoute = nullptr;
97 if(dst->containingAS() == this && src->containingAS() == this ){
98 if (bypassRoutes_.find({src->name(),dst->name()}) != bypassRoutes_.end()) {
99 bypassedRoute = bypassRoutes_.at({src->name(),dst->name()});
100 XBT_DEBUG("Found a bypass route with %zu links",bypassedRoute->size());
102 return bypassedRoute;
105 /* (2) find the path to the root routing component */
106 std::vector<As*> path_src;
107 As *current = src->containingAS();
108 while (current != nullptr) {
109 path_src.push_back(current);
110 current = current->father_;
113 std::vector<As*> path_dst;
114 current = dst->containingAS();
115 while (current != nullptr) {
116 path_dst.push_back(current);
117 current = current->father_;
120 /* (3) find the common father */
121 while (path_src.size() > 1 && path_dst.size() >1
122 && path_src.at(path_src.size() -1) == path_dst.at(path_dst.size() -1)) {
127 int max_index_src = path_src.size() - 1;
128 int max_index_dst = path_dst.size() - 1;
130 int max_index = std::max(max_index_src, max_index_dst);
132 for (int max = 0; max <= max_index; max++) {
133 for (int i = 0; i < max; i++) {
134 if (i <= max_index_src && max <= max_index_dst) {
135 const std::pair<std::string, std::string> key = {path_src.at(i)->name(), path_dst.at(max)->name()};
136 if (bypassRoutes_.find(key) != bypassRoutes_.end())
137 bypassedRoute = bypassRoutes_.at(key);
141 if (max <= max_index_src && i <= max_index_dst) {
142 const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(i)->name()};
143 if (bypassRoutes_.find(key) != bypassRoutes_.end())
144 bypassedRoute = bypassRoutes_.at(key);
153 if (max <= max_index_src && max <= max_index_dst) {
154 const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(max)->name()};
155 if (bypassRoutes_.find(key) != bypassRoutes_.end())
156 bypassedRoute = bypassRoutes_.at(key);
162 return bypassedRoute;
166 * \brief Recursive function for getRouteAndLatency
168 * \param src the source host
169 * \param dst the destination host
170 * \param links Where to store the links and the gw information
171 * \param latency If not nullptr, the latency of all links will be added in it
173 void AsImpl::getRouteRecursive(routing::NetCard *src, routing::NetCard *dst,
174 /* OUT */ std::vector<surf::Link*> * links, double *latency)
176 s_sg_platf_route_cbarg_t route;
177 memset(&route,0,sizeof(route));
179 XBT_DEBUG("Solve route/latency \"%s\" to \"%s\"", src->name(), dst->name());
181 /* Find how src and dst are interconnected */
182 AsImpl *common_ancestor, *src_ancestor, *dst_ancestor;
183 find_common_ancestors(src, dst, &common_ancestor, &src_ancestor, &dst_ancestor);
184 XBT_DEBUG("elements_father: common ancestor '%s' src ancestor '%s' dst ancestor '%s'",
185 common_ancestor->name(), src_ancestor->name(), dst_ancestor->name());
187 /* Check whether a direct bypass is defined. If so, use it and bail out */
188 std::vector<surf::Link*> *bypassed_route = common_ancestor->getBypassRoute(src, dst);
189 if (nullptr != bypassed_route) {
190 for (surf::Link *link : *bypassed_route) {
191 links->push_back(link);
193 *latency += link->getLatency();
198 /* If src and dst are in the same AS, life is good */
199 if (src_ancestor == dst_ancestor) { /* SURF_ROUTING_BASE */
200 route.link_list = links;
201 common_ancestor->getRouteAndLatency(src, dst, &route, latency);
205 /* Not in the same AS, no bypass. We'll have to find our path between the ASes recursively*/
207 route.link_list = new std::vector<surf::Link*>();
209 common_ancestor->getRouteAndLatency(src_ancestor->netcard_, dst_ancestor->netcard_, &route, latency);
210 xbt_assert((route.gw_src != nullptr) && (route.gw_dst != nullptr),
211 "bad gateways for route from \"%s\" to \"%s\"", src->name(), dst->name());
213 /* If source gateway is not our source, we have to recursively find our way up to this point */
214 if (src != route.gw_src)
215 getRouteRecursive(src, route.gw_src, links, latency);
216 for (auto link: *route.link_list)
217 links->push_back(link);
218 delete route.link_list;
220 /* If dest gateway is not our destination, we have to recursively find our way from this point */
221 if (route.gw_dst != dst)
222 getRouteRecursive(route.gw_dst, dst, links, latency);