+/*
+ * Compute the maximum hop count for this node and it's children. The
+ * maximum hop count is the maximum number of connections between any
+ * two nodes in the subtree rooted at this node. We need this for
+ * setting the gap count. As we build the tree bottom up in
+ * build_tree() below, this is fairly easy to do: for each node we
+ * maintain the max hop count and the max depth, ie the number of hops
+ * to the furthest leaf. Computing the max hop count breaks down into
+ * two cases: either the path goes through this node, in which case
+ * the hop count is the sum of the two biggest child depths plus 2.
+ * Or it could be the case that the max hop path is entirely
+ * containted in a child tree, in which case the max hop count is just
+ * the max hop count of this child.
+ */
+static void update_hop_count(struct fw_node *node)
+{
+ int depths[2] = { -1, -1 };
+ int max_child_hops = 0;
+ int i;
+
+ for (i = 0; i < node->port_count; i++) {
+ if (node->ports[i] == NULL)
+ continue;
+
+ if (node->ports[i]->max_hops > max_child_hops)
+ max_child_hops = node->ports[i]->max_hops;
+
+ if (node->ports[i]->max_depth > depths[0]) {
+ depths[1] = depths[0];
+ depths[0] = node->ports[i]->max_depth;
+ } else if (node->ports[i]->max_depth > depths[1])
+ depths[1] = node->ports[i]->max_depth;
+ }
+
+ node->max_depth = depths[0] + 1;
+ node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
+}
+
+static inline struct fw_node *fw_node(struct list_head *l)
+{
+ return list_entry(l, struct fw_node, link);
+}
+