31 Oct
2011
31 Oct
'11
12:08 a.m.
On Sun, Oct 30, 2011 at 09:55:59AM +0100, Antonio Quartulli wrote:
[...]
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(orig_node, node, head,
+ hash_entry) {
+ if (orig_node->dht_hash > ip_key)
+ tmp_max = USHRT_MAX -
+ orig_node->dht_hash + ip_key;
+ else
+ tmp_max = ip_key - orig_node->dht_hash;
+
+ /* this is closest! */
+ if (tmp_max <= max)
+ continue;
+
+ /* this has already been selected */
+ if (tmp_max > last_max)
+ continue;
+
+ if (!atomic_inc_not_zero(&orig_node->refcount))
+ continue;
+
+ /* In case of hash collision we can select two
+ * nodes with the same hash, but we have ensure
+ * they are different */
+ if (tmp_max == last_max) {
+ for (j = 0; j < select; j++)
+ if (res[j].orig_node ==
+ orig_node)
+ break;
+ if (j < select)
+ continue;
+ }
+
+ if (!atomic_inc_not_zero(&orig_node->refcount))
+ continue;
Why do you increase the refcount two times? If it is really required, please
add a comment.
+
+ max = tmp_max;
+ if (max_orig_node)
+ orig_node_free_ref(max_orig_node);
+ max_orig_node = orig_node;
+ }
+ rcu_read_unlock();
+ }
+ last_max = max;
+ if (max_orig_node) {
+ res[select].type = DHT_CANDIDATE_ORIG;
+ res[select].orig_node = max_orig_node;
+ bat_dbg(DBG_ARP, bat_priv, "DHT_SEL_CAND %d: %pM %u\n",
+ select, max_orig_node->orig, max);
+ }
+ if (res[select].type == DHT_CANDIDATE_ME) {
+ chosen_me = true;
+ bat_dbg(DBG_ARP, bat_priv, "DHT_SEL_CAND %d: ME %u\n",
+ select, bat_priv->dht_hash);
+ }
+
+ max_orig_node = NULL;
+ }
+
+ return res;
+}
+
+/*
+ * Sends the skb payload passed as argument to the candidates selected for
+ * 'ip'. The skb is copied by means of pskb_copy() and is sent as unicast
packet
+ * to each of the selected candidate. */
+static bool dht_send_data(struct bat_priv *bat_priv, struct sk_buff *skb,
+ uint32_t ip)
+{
+ int i;
+ bool ret = false;
+ struct neigh_node *neigh_node = NULL;
+ struct sk_buff *tmp_skb;
+ struct dht_candidate *cand = dht_select_candidates(bat_priv, ip);
+
+ if (!cand)
+ goto out;
+
+ bat_dbg(DBG_ARP, bat_priv, "DHT_SEND for %pI4\n", &ip);
+
+ for (i = 0; i < DHT_CANDIDATES_NUM; i++) {
+ if (cand[i].type == DHT_CANDIDATE_ME ||
+ cand[i].type == DHT_CANDIDATE_NULL) {
+ continue;
+ }
no braces are required here.
+
+ neigh_node = orig_node_get_router(cand[i].orig_node);
+ if (!neigh_node)
+ goto free_orig;
+
+ tmp_skb = pskb_copy(skb, GFP_ATOMIC);
+ tmp_skb = prepare_unicast_packet(tmp_skb, cand[i].orig_node);
+ if (tmp_skb)
+ send_skb_packet(tmp_skb, neigh_node->if_incoming,
+ neigh_node->addr);
+ /* set ret to true only if we send at least one request */
+ ret = true;
+ neigh_node_free_ref(neigh_node);
+free_orig:
+ orig_node_free_ref(cand[i].orig_node);
+ }
+
+out:
+ kfree(cand);
+ return ret;
+}