Algorithmique Numérique Distribuée Public GIT Repository
 author Martin Quinson Tue, 1 Nov 2016 18:27:12 +0000 (19:27 +0100) committer Martin Quinson Tue, 1 Nov 2016 18:27:12 +0000 (19:27 +0100)

index afca765..9685649 100644 (file)
@@ -39,10 +39,69 @@ namespace simgrid {
return nullptr;
}

-  /** @brief Get the common ancestor and its first children in each line leading to src and dst */
+  /** @brief Get the common ancestor and its first children in each line leading to src and dst
+   *
+   * In the recursive case, this sets common_ancestor, src_ancestor and dst_ancestor are set as follows.
+   * @verbatim
+   *         platform root
+   *               |
+   *              ...                <- possibly long path
+   *               |
+   *         common_ancestor
+   *           /        \
+   *          /          \
+   *         /            \          <- direct link
+   *        /              \
+   *       /                \
+   *  src_ancestor     dst_ancestor  <- must be different in the recursive case
+   *      |                   |
+   *     ...                 ...     <-- possibly long (or null) pathes
+   *      |                   |
+   *     src                 dst
+   *  @endverbatim
+   *
+   *  In the base case (when src and dst are in the same AS), things are as follows:
+   *  @verbatim
+   *                  platform root
+   *                        |
+   *                       ...                      <- possibly long path
+   *                        |
+   * common_ancestor==src_ancestor==dst_ancestor    <-- all the same value
+   *                   /        \
+   *                  /          \                  <- direct links
+   *                 /            \
+   *              src              dst
+   *  @endverbatim
+   *
+   * A specific recursive case occurs when src is the ancestor of dst. In this case,
+   * the base case routing should be used so the common_ancestor is specifically set
+   * to src_ancestor==dst_ancestor.
+   * Naturally, things are completely symmetrical if dst is the ancestor of src.
+   * @verbatim
+   *            platform root
+   *                  |
+   *                 ...                <-- possibly long path
+   *                  |
+   *  src == src_ancestor==dst_ancestor==common_ancestor <-- same value
+   *                  |
+   *                 ...                <-- possibly long (or null) path
+   *                  |
+   *                 dst
+   *  @endverbatim
+   */
static void find_common_ancestors(NetCard* src, NetCard* dst,
/* OUT */ AsImpl** common_ancestor, AsImpl** src_ancestor, AsImpl** dst_ancestor)
{
+    /* Deal with the easy base case */
+    if (src->containingAS() == dst->containingAS()) {
+      *common_ancestor = src->containingAS();
+      *src_ancestor    = *common_ancestor;
+      *dst_ancestor    = *common_ancestor;
+      return;
+    }
+
+  /* engage the full recursive search */
+
#define ROUTING_HIERARCHY_MAXDEPTH 32 /* increase if it is not enough */
AsImpl* path_src[ROUTING_HIERARCHY_MAXDEPTH];
AsImpl* path_dst[ROUTING_HIERARCHY_MAXDEPTH];
@@ -50,7 +109,6 @@ namespace simgrid {
int index_dst = 0;
AsImpl* current_src;
AsImpl* current_dst;
-    AsImpl* father;

/* (1) find the path to root of src and dst*/
AsImpl* src_as = src->containingAS();
@@ -73,45 +131,54 @@ namespace simgrid {
/* (3) find the common father.
* Before that, index_src and index_dst may be different, they both point to nullptr in path_src/path_dst
* So we move them down simultaneously as long as they point to the same content.
+     *
+     * This works because all SimGrid platform have a unique root element (that is the last element of both paths).
*/
do {
current_src = path_src[--index_src];
current_dst = path_dst[--index_dst];
} while (index_src > 0 && index_dst > 0 && current_src == current_dst);

-    /* (4) if we did not find a difference (index_src or index_dst went to 0), both elements are in the same AS */
-    if (current_src == current_dst)
-      father = current_src;
-    else // we found a difference
-      father = path_src[index_src + 1];
-
-    /* (5) result generation */
-    *common_ancestor = father;      /* the common father of src and dst */
+    /* (4) we found the difference at least. Finalize the returned values */
*src_ancestor    = current_src; /* the first different father of src */
*dst_ancestor    = current_dst; /* the first different father of dst */
+    if (current_src == current_dst) { // One is the ancestor of the other
+      *common_ancestor = current_src;
+    } else {
+      *common_ancestor = path_src[index_src + 1];
+    }
#undef ROUTING_HIERARCHY_MAXDEPTH
}

-
/* PRECONDITION: this is the common ancestor of src and dst */
-    std::vector<surf::Link*> *AsImpl::getBypassRoute(routing::NetCard *src, routing::NetCard *dst)
+    bool AsImpl::getBypassRoute(routing::NetCard* src, routing::NetCard* dst,
{
// If never set a bypass route return nullptr without any further computations
XBT_DEBUG("generic_get_bypassroute from %s to %s", src->name(), dst->name());
if (bypassRoutes_.empty())
-        return nullptr;
-
+        return false;

+      /* Base case, no recursion is needed */
if(dst->containingAS() == this && src->containingAS() == this ){
if (bypassRoutes_.find({src->name(),dst->name()}) != bypassRoutes_.end()) {
-          bypassedRoute = bypassRoutes_.at({src->name(),dst->name()});
+          std::vector<surf::Link*>* bypassedRoute = bypassRoutes_.at({src->name(), dst->name()});
+            if (latency)
+          }
XBT_DEBUG("Found a bypass route with %zu links",bypassedRoute->size());
+          return true;
}
-        return bypassedRoute;
+        return false;
}

-      /* (2) find the path to the root routing component */
+      /* Engage recursive search */
+
+
+      /* (1) find the path to the root routing component */
std::vector<As*> path_src;
As *current = src->containingAS();
while (current != nullptr) {
@@ -126,7 +193,7 @@ namespace simgrid {
current = current->father_;
}

-      /* (3) find the common father */
+      /* (2) find the common father */
while (path_src.size() > 1 && path_dst.size() >1
&& path_src.at(path_src.size() -1) == path_dst.at(path_dst.size() -1)) {
path_src.pop_back();
@@ -142,18 +209,18 @@ namespace simgrid {
for (int i = 0; i < max; i++) {
if (i <= max_index_src && max <= max_index_dst) {
const std::pair<std::string, std::string> key = {path_src.at(i)->name(), path_dst.at(max)->name()};
-            if (bypassRoutes_.find(key) != bypassRoutes_.end())
+            if (bypassRoutes_.find(key) != bypassRoutes_.end()) {
bypassedRoute = bypassRoutes_.at(key);
+              break;
+            }
}
-          if (bypassedRoute)
-            break;
if (max <= max_index_src && i <= max_index_dst) {
const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(i)->name()};
-            if (bypassRoutes_.find(key) != bypassRoutes_.end())
+            if (bypassRoutes_.find(key) != bypassRoutes_.end()) {
bypassedRoute = bypassRoutes_.at(key);
+              break;
+            }
}
-          if (bypassedRoute)
-            break;
}

if (bypassedRoute)
@@ -161,14 +228,22 @@ namespace simgrid {

if (max <= max_index_src && max <= max_index_dst) {
const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(max)->name()};
-          if (bypassRoutes_.find(key) != bypassRoutes_.end())
+          if (bypassRoutes_.find(key) != bypassRoutes_.end()) {
bypassedRoute = bypassRoutes_.at(key);
+            break;
+          }
}
-        if (bypassedRoute)
-          break;
}

-      return bypassedRoute;
+      if (bypassedRoute) {
+          if (latency)
+        }
+        return true;
+      }
+      return false;
}

/**
@@ -194,15 +269,8 @@ namespace simgrid {
common_ancestor->name(), src_ancestor->name(), dst_ancestor->name());

/* Check whether a direct bypass is defined. If so, use it and bail out */
-      std::vector<surf::Link*> *bypassed_route = common_ancestor->getBypassRoute(src, dst);
-      if (nullptr != bypassed_route) {
-          if (latency)
-        }
+      if (common_ancestor->getBypassRoute(src, dst, links, latency))
return;
-      }

/* If src and dst are in the same AS, life is good */
if (src_ancestor == dst_ancestor) {       /* SURF_ROUTING_BASE */
index 7ebe6a3..5abdb28 100644 (file)
@@ -60,7 +60,9 @@ public:
virtual void getRouteAndLatency(NetCard *src, NetCard *dst, sg_platf_route_cbarg_t into, double *latency)=0;
/** @brief retrieves the list of all routes of size 1 (of type src x dst x Link) */
-  std::vector<surf::Link*> *getBypassRoute(routing::NetCard *src, routing::NetCard *dst);
+  /* returns whether we found a bypass path */
+  bool getBypassRoute(routing::NetCard * src, routing::NetCard * dst,

virtual void getGraph(xbt_graph_t graph, xbt_dict_t nodes, xbt_dict_t edges)=0;
static void getRouteRecursive(routing::NetCard *src, routing::NetCard *dst, /* OUT */ std::vector<surf::Link*> * links, double *latency);
index b6c6e65..1728b56 100644 (file)
@@ -144,13 +144,13 @@ static void check_disk_attachment()
xbt_lib_cursor_t cursor;
char *key;
void **data;
-  simgrid::kernel::routing::NetCard *host_elm;
xbt_lib_foreach(storage_lib, cursor, key, data) {
-    if(xbt_lib_get_level(xbt_lib_get_elm_or_null(storage_lib, key), SURF_STORAGE_LEVEL) != nullptr) {
-    simgrid::surf::Storage *storage = static_cast<simgrid::surf::Storage*>(xbt_lib_get_level(xbt_lib_get_elm_or_null(storage_lib, key), SURF_STORAGE_LEVEL));
-    host_elm = sg_netcard_by_name_or_null(storage->attach_);
-    if(!host_elm)
-      surf_parse_error("Unable to attach storage %s: host %s doesn't exist.", storage->getName(), storage->attach_);
+    if (xbt_lib_get_level(xbt_lib_get_elm_or_null(storage_lib, key), SURF_STORAGE_LEVEL) != nullptr) {
+      simgrid::surf::Storage* storage =
+          static_cast<simgrid::surf::Storage*>(xbt_lib_get_or_null(storage_lib, key, SURF_STORAGE_LEVEL));
+      simgrid::kernel::routing::NetCard* host_elm = sg_netcard_by_name_or_null(storage->attach_);
+      if (!host_elm)
+        surf_parse_error("Unable to attach storage %s: host %s doesn't exist.", storage->getName(), storage->attach_);
}
}
}