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)
22 xbt_dynar_free(&upDownLinks);
26 xbt_dynar_t AsImpl::getOneLinkRoutes() {
30 /** @brief Get the common ancestor and its first childs in each line leading to src and dst */
31 static void find_common_ancestors(NetCard *src, NetCard *dst,
32 /* OUT */ AsImpl **common_ancestor, AsImpl **src_ancestor, AsImpl **dst_ancestor)
34 #define ROUTING_HIERARCHY_MAXDEPTH 32 /* increase if it is not enough */
35 AsImpl *path_src[ROUTING_HIERARCHY_MAXDEPTH];
36 AsImpl *path_dst[ROUTING_HIERARCHY_MAXDEPTH];
43 /* (1) find the path to root of src and dst*/
44 AsImpl *src_as = src->containingAS();
45 AsImpl *dst_as = dst->containingAS();
47 xbt_assert(src_as, "Host %s must be in an AS", src->name());
48 xbt_assert(dst_as, "Host %s must be in an AS", dst->name());
50 /* (2) find the path to the root routing component */
51 for (AsImpl *current = src_as; current != NULL; current = static_cast<AsImpl*>(current->father())) {
52 xbt_assert(index_src < ROUTING_HIERARCHY_MAXDEPTH, "ROUTING_HIERARCHY_MAXDEPTH should be increased for element %s", src->name());
53 path_src[index_src++] = current;
55 for (AsImpl *current = dst_as; current != NULL; current = static_cast<AsImpl*>(current->father())) {
56 xbt_assert(index_dst < ROUTING_HIERARCHY_MAXDEPTH,"ROUTING_HIERARCHY_MAXDEPTH should be increased for path_dst");
57 path_dst[index_dst++] = current;
60 /* (3) find the common father.
61 * Before that, index_src and index_dst may be different, they both point to NULL in path_src/path_dst
62 * So we move them down simultaneously as long as they point to the same content.
65 current_src = path_src[--index_src];
66 current_dst = path_dst[--index_dst];
67 } while (index_src > 0 && index_dst > 0 && current_src == current_dst);
69 /* (4) if we did not find a difference (index_src or index_dst went to 0), both elements are in the same AS */
70 if (current_src == current_dst)
72 else // we found a difference
73 father = path_src[index_src + 1];
75 /* (5) result generation */
76 *common_ancestor = father; /* the common father of src and dst */
77 *src_ancestor = current_src; /* the first different father of src */
78 *dst_ancestor = current_dst; /* the first different father of dst */
79 #undef ROUTING_HIERARCHY_MAXDEPTH
83 /* PRECONDITION: this is the common ancestor of src and dst */
84 std::vector<surf::Link*> *AsImpl::getBypassRoute(surf::NetCard *src, surf::NetCard *dst)
86 // If never set a bypass route return NULL without any further computations
87 XBT_DEBUG("generic_get_bypassroute from %s to %s", src->name(), dst->name());
88 if (bypassRoutes_.empty())
91 std::vector<surf::Link*> *bypassedRoute = nullptr;
93 if(dst->containingAS() == this && src->containingAS() == this ){
94 if (bypassRoutes_.find({src->name(),dst->name()}) != bypassRoutes_.end()) {
95 bypassedRoute = bypassRoutes_.at({src->name(),dst->name()});
96 XBT_DEBUG("Found a bypass route with %zu links",bypassedRoute->size());
101 /* (2) find the path to the root routing component */
102 std::vector<As*> path_src;
103 As *current = src->containingAS();
104 while (current != NULL) {
105 path_src.push_back(current);
106 current = current->father_;
109 std::vector<As*> path_dst;
110 current = dst->containingAS();
111 while (current != NULL) {
112 path_dst.push_back(current);
113 current = current->father_;
116 /* (3) find the common father */
117 while (path_src.size() > 1 && path_dst.size() >1
118 && path_src.at(path_src.size() -1) == path_dst.at(path_dst.size() -1)) {
123 int max_index_src = path_src.size() - 1;
124 int max_index_dst = path_dst.size() - 1;
126 int max_index = std::max(max_index_src, max_index_dst);
128 for (int max = 0; max <= max_index; max++) {
129 for (int i = 0; i < max; i++) {
130 if (i <= max_index_src && max <= max_index_dst) {
131 const std::pair<std::string, std::string> key = {path_src.at(i)->name(), path_dst.at(max)->name()};
132 if (bypassRoutes_.find(key) != bypassRoutes_.end())
133 bypassedRoute = bypassRoutes_.at(key);
137 if (max <= max_index_src && i <= max_index_dst) {
138 const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(i)->name()};
139 if (bypassRoutes_.find(key) != bypassRoutes_.end())
140 bypassedRoute = bypassRoutes_.at(key);
149 if (max <= max_index_src && max <= max_index_dst) {
150 const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(max)->name()};
151 if (bypassRoutes_.find(key) != bypassRoutes_.end())
152 bypassedRoute = bypassRoutes_.at(key);
158 return bypassedRoute;
162 * \brief Recursive function for getRouteAndLatency
164 * \param src the source host
165 * \param dst the destination host
166 * \param links Where to store the links and the gw information
167 * \param latency If not NULL, the latency of all links will be added in it
169 void AsImpl::getRouteRecursive(surf::NetCard *src, surf::NetCard *dst,
170 /* OUT */ std::vector<surf::Link*> * links, double *latency)
172 s_sg_platf_route_cbarg_t route;
173 memset(&route,0,sizeof(route));
175 XBT_DEBUG("Solve route/latency \"%s\" to \"%s\"", src->name(), dst->name());
177 /* Find how src and dst are interconnected */
178 AsImpl *common_ancestor, *src_ancestor, *dst_ancestor;
179 find_common_ancestors(src, dst, &common_ancestor, &src_ancestor, &dst_ancestor);
180 XBT_DEBUG("elements_father: common ancestor '%s' src ancestor '%s' dst ancestor '%s'",
181 common_ancestor->name(), src_ancestor->name(), dst_ancestor->name());
183 /* Check whether a direct bypass is defined. If so, use it and bail out */
184 std::vector<surf::Link*> *bypassed_route = common_ancestor->getBypassRoute(src, dst);
185 if (nullptr != bypassed_route) {
186 for (surf::Link *link : *bypassed_route) {
187 links->push_back(link);
189 *latency += link->getLatency();
194 /* If src and dst are in the same AS, life is good */
195 if (src_ancestor == dst_ancestor) { /* SURF_ROUTING_BASE */
196 route.link_list = links;
197 common_ancestor->getRouteAndLatency(src, dst, &route, latency);
201 /* Not in the same AS, no bypass. We'll have to find our path between the ASes recursively*/
203 route.link_list = new std::vector<surf::Link*>();
205 common_ancestor->getRouteAndLatency(src_ancestor->netcard_, dst_ancestor->netcard_, &route, latency);
206 xbt_assert((route.gw_src != NULL) && (route.gw_dst != NULL),
207 "bad gateways for route from \"%s\" to \"%s\"", src->name(), dst->name());
209 /* If source gateway is not our source, we have to recursively find our way up to this point */
210 if (src != route.gw_src)
211 getRouteRecursive(src, route.gw_src, links, latency);
212 for (auto link: *route.link_list)
213 links->push_back(link);
215 /* If dest gateway is not our destination, we have to recursively find our way from this point */
216 if (route.gw_dst != dst)
217 getRouteRecursive(route.gw_dst, dst, links, latency);