+/*
+ * Stop tracing for a specific UST session and app.
+ */
+int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
+{
+ int ret = 0;
+ struct ust_app_session *ua_sess;
+
+ DBG("Stopping tracing for ust app pid %d", app->key.pid);
+
+ rcu_read_lock();
+
+ ua_sess = lookup_session_by_app(usess, app);
+ if (ua_sess == NULL) {
+ /* Only malloc can failed so something is really wrong */
+ goto error_rcu_unlock;
+ }
+
+#if 0 /* only useful when periodical flush will be supported */
+ /* need to keep a handle on shm in session for this. */
+ /* Flush all buffers before stopping */
+ ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
+ if (ret < 0) {
+ ERR("UST metadata flush failed");
+ }
+
+ cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
+ ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
+ if (ret < 0) {
+ ERR("UST flush buffer error");
+ }
+ }
+#endif
+
+ /* This inhibits UST tracing */
+ ret = ustctl_stop_session(app->key.sock, ua_sess->handle);
+ if (ret < 0) {
+ ERR("Error stopping tracing for app pid: %d", app->key.pid);
+ goto error_rcu_unlock;
+ }
+
+ rcu_read_unlock();
+
+ /* Quiescent wait after stopping trace */
+ ustctl_wait_quiescent(app->key.sock);
+
+ return 0;
+
+error_rcu_unlock:
+ rcu_read_unlock();
+ return -1;
+}
+