+void ust_app_unregister(int sock)
+{
+ struct ust_app *lta;
+ struct cds_lfht_node *node;
+ struct cds_lfht_iter iter;
+
+ rcu_read_lock();
+ lta = find_app_by_sock(sock);
+ if (lta == NULL) {
+ ERR("Unregister app sock %d not found!", sock);
+ goto error;
+ }
+
+ DBG("PID %d unregistering with sock %d", lta->key.pid, sock);
+
+ /* Get the node reference for a call_rcu */
+ node = hashtable_lookup(ust_app_ht,
+ (void *)((unsigned long) lta->key.pid), sizeof(void *), &iter);
+ if (node == NULL) {
+ ERR("Unable to find app sock %d by pid %d", sock, lta->key.pid);
+ goto error;
+ }
+
+ hashtable_del(ust_app_ht, &iter);
+ call_rcu(&node->head, delete_ust_app_rcu);
+error:
+ rcu_read_unlock();
+ return;
+}
+
+/*
+ * Return traceable_app_count
+ */
+unsigned long ust_app_list_count(void)
+{
+ unsigned long count;
+
+ rcu_read_lock();
+ count = hashtable_get_count(ust_app_ht);
+ rcu_read_unlock();
+
+ return count;
+}
+
+/*
+ * Fill events array with all events name of all registered apps.
+ */
+int ust_app_list_events(struct lttng_event **events)
+{
+ int ret, handle;
+ size_t nbmem, count = 0;
+ struct cds_lfht_iter iter;
+ struct ust_app *app;
+ struct lttng_event *tmp;
+
+ nbmem = UST_APP_EVENT_LIST_SIZE;
+ tmp = zmalloc(nbmem * sizeof(struct lttng_event));
+ if (tmp == NULL) {
+ PERROR("zmalloc ust app events");
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ rcu_read_lock();
+
+ cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
+ handle = ustctl_tracepoint_list(app->key.sock);
+ if (handle < 0) {
+ ERR("UST app list events getting handle failed for app pid %d",
+ app->key.pid);
+ continue;
+ }
+
+ while ((ret = ustctl_tracepoint_list_get(app->key.sock, handle,
+ tmp[count].name)) != -ENOENT) {
+ if (count > nbmem) {
+ DBG2("Reallocating event list from %zu to %zu bytes", nbmem,
+ nbmem + UST_APP_EVENT_LIST_SIZE);
+ nbmem += UST_APP_EVENT_LIST_SIZE;
+ tmp = realloc(tmp, nbmem);
+ if (tmp == NULL) {
+ PERROR("realloc ust app events");
+ ret = -ENOMEM;
+ goto rcu_error;
+ }
+ }
+
+ tmp[count].type = LTTNG_UST_TRACEPOINT;
+ tmp[count].pid = app->key.pid;
+ tmp[count].enabled = -1;
+ count++;
+ }
+ }
+
+ ret = count;
+ *events = tmp;
+
+ DBG2("UST app list events done (%zu events)", count);
+
+rcu_error:
+ rcu_read_unlock();
+error:
+ return ret;
+}
+
+/*
+ * Free and clean all traceable apps of the global list.
+ */
+void ust_app_clean_list(void)
+{
+ int ret;
+ struct cds_lfht_node *node;
+ struct cds_lfht_iter iter;
+ struct ust_app *app;
+
+ DBG2("UST app cleaning registered apps hash table");
+
+ rcu_read_lock();
+
+ cds_lfht_for_each(ust_app_ht, &iter, node) {
+ app = caa_container_of(node, struct ust_app, node);
+
+ ret = hashtable_del(ust_app_ht, &iter);
+ if (!ret) {
+ call_rcu(&node->head, delete_ust_app_rcu);
+ }
+ }
+
+ hashtable_destroy(ust_app_ht);
+ hashtable_destroy(ust_app_sock_key_map);
+
+ rcu_read_unlock();
+}
+
+/*
+ * Init UST app hash table.
+ */
+void ust_app_ht_alloc(void)
+{
+ ust_app_ht = hashtable_new(0);
+ ust_app_sock_key_map = hashtable_new(0);
+}
+
+/*
+ * For a specific UST session, create the channel for all registered apps.
+ */
+int ust_app_create_channel_all(struct ltt_ust_session *usess,